Sample records for increasing human population

  1. Increasing cell culture population doublings for long-term growth of finite life span human cell cultures

    DOEpatents

    Stampfer, Martha R.; Garbe, James C.

    2016-06-28

    Cell culture media formulations for culturing human epithelial cells are herein described. Also described are methods of increasing population doublings in a cell culture of finite life span human epithelial cells and prolonging the life span of human cell cultures. Using the cell culture media disclosed alone and in combination with addition to the cell culture of a compound associated with anti-stress activity achieves extended growth of pre-stasis cells and increased population doublings and life span in human epithelial cell cultures.

  2. Increasing cell culture population doublings for long-term growth of finite life span human cell cultures

    DOEpatents

    Stampfer, Martha R; Garbe, James C

    2015-02-24

    Cell culture media formulations for culturing human epithelial cells are herein described. Also described are methods of increasing population doublings in a cell culture of finite life span human epithelial cells and prolonging the life span of human cell cultures. Using the cell culture media disclosed alone and in combination with addition to the cell culture of a compound associated with anti-stress activity achieves extended growth of pre-stasis cells and increased population doublings and life span in human epithelial cell cultures.

  3. The Effect of an Extreme and Prolonged Population Bottleneck on Patterns of Deleterious Variation: Insights from the Greenlandic Inuit.

    PubMed

    Pedersen, Casper-Emil T; Lohmueller, Kirk E; Grarup, Niels; Bjerregaard, Peter; Hansen, Torben; Siegismund, Hans R; Moltke, Ida; Albrechtsen, Anders

    2017-02-01

    The genetic consequences of population bottlenecks on patterns of deleterious genetic variation in human populations are of tremendous interest. Based on exome sequencing of 18 Greenlandic Inuit we show that the Inuit have undergone a severe ∼20,000-year-long bottleneck. This has led to a markedly more extreme distribution of allele frequencies than seen for any other human population tested to date, making the Inuit the perfect population for investigating the effect of a bottleneck on patterns of deleterious variation. When comparing proxies for genetic load that assume an additive effect of deleterious alleles, the Inuit show, at most, a slight increase in load compared to European, East Asian, and African populations. Specifically, we observe <4% increase in the number of derived deleterious alleles in the Inuit. In contrast, proxies for genetic load under a recessive model suggest that the Inuit have a significantly higher load (20% increase or more) compared to other less bottlenecked human populations. Forward simulations under realistic models of demography support our empirical findings, showing up to a 6% increase in the genetic load for the Inuit population across all models of dominance. Further, the Inuit population carries fewer deleterious variants than other human populations, but those that are present tend to be at higher frequency than in other populations. Overall, our results show how recent demographic history has affected patterns of deleterious variants in human populations. Copyright © 2017 by the Genetics Society of America.

  4. Faster Increases in Human Life Expectancy Could Lead to Slower Population Aging

    PubMed Central

    2015-01-01

    Counterintuitively, faster increases in human life expectancy could lead to slower population aging. The conventional view that faster increases in human life expectancy would lead to faster population aging is based on the assumption that people become old at a fixed chronological age. A preferable alternative is to base measures of aging on people’s time left to death, because this is more closely related to the characteristics that are associated with old age. Using this alternative interpretation, we show that faster increases in life expectancy would lead to slower population aging. Among other things, this finding affects the assessment of the speed at which countries will age. PMID:25876033

  5. Conservation threats due to human-caused increases in fire frequency in Mediterranean-climate ecosystems.

    PubMed

    Syphard, Alexandra D; Radeloff, Volker C; Hawbaker, Todd J; Stewart, Susan I

    2009-06-01

    Periodic wildfire is an important natural process in Mediterranean-climate ecosystems, but increasing fire recurrence threatens the fragile ecology of these regions. Because most fires are human-caused, we investigated how human population patterns affect fire frequency. Prior research in California suggests the relationship between population density and fire frequency is not linear. There are few human ignitions in areas with low population density, so fire frequency is low. As population density increases, human ignitions and fire frequency also increase, but beyond a density threshold, the relationship becomes negative as fuels become sparser and fire suppression resources are concentrated. We tested whether this hypothesis also applies to the other Mediterranean-climate ecosystems of the world. We used global satellite databases of population, fire activity, and land cover to evaluate the spatial relationship between humans and fire in the world's five Mediterranean-climate ecosystems. Both the mean and median population densities were consistently and substantially higher in areas with than without fire, but fire again peaked at intermediate population densities, which suggests that the spatial relationship is complex and nonlinear. Some land-cover types burned more frequently than expected, but no systematic differences were observed across the five regions. The consistent association between higher population densities and fire suggests that regardless of differences between land-cover types, natural fire regimes, or overall population, the presence of people in Mediterranean-climate regions strongly affects the frequency of fires; thus, population growth in areas now sparsely settled presents a conservation concern. Considering the sensitivity of plant species to repeated burning and the global conservation significance of Mediterranean-climate ecosystems, conservation planning needs to consider the human influence on fire frequency. Fine-scale spatial analysis of relationships between people and fire may help identify areas where increases in fire frequency will threaten ecologically valuable areas. ©2009 Society for Conservation Biology.

  6. A multi-scale study of Orthoptera species richness and human population size controlling for sampling effort

    NASA Astrophysics Data System (ADS)

    Cantarello, Elena; Steck, Claude E.; Fontana, Paolo; Fontaneto, Diego; Marini, Lorenzo; Pautasso, Marco

    2010-03-01

    Recent large-scale studies have shown that biodiversity-rich regions also tend to be densely populated areas. The most obvious explanation is that biodiversity and human beings tend to match the distribution of energy availability, environmental stability and/or habitat heterogeneity. However, the species-people correlation can also be an artefact, as more populated regions could show more species because of a more thorough sampling. Few studies have tested this sampling bias hypothesis. Using a newly collated dataset, we studied whether Orthoptera species richness is related to human population size in Italy’s regions (average area 15,000 km2) and provinces (2,900 km2). As expected, the observed number of species increases significantly with increasing human population size for both grain sizes, although the proportion of variance explained is minimal at the provincial level. However, variations in observed Orthoptera species richness are primarily associated with the available number of records, which is in turn well correlated with human population size (at least at the regional level). Estimated Orthoptera species richness (Chao2 and Jackknife) also increases with human population size both for regions and provinces. Both for regions and provinces, this increase is not significant when controlling for variation in area and number of records. Our study confirms the hypothesis that broad-scale human population-biodiversity correlations can in some cases be artefactual. More systematic sampling of less studied taxa such as invertebrates is necessary to ascertain whether biogeographical patterns persist when sampling effort is kept constant or included in models.

  7. Relationships between human population density and burned area at continental and global scales.

    PubMed

    Bistinas, Ioannis; Oom, Duarte; Sá, Ana C L; Harrison, Sandy P; Prentice, I Colin; Pereira, José M C

    2013-01-01

    We explore the large spatial variation in the relationship between population density and burned area, using continental-scale Geographically Weighted Regression (GWR) based on 13 years of satellite-derived burned area maps from the global fire emissions database (GFED) and the human population density from the gridded population of the world (GPW 2005). Significant relationships are observed over 51.5% of the global land area, and the area affected varies from continent to continent: population density has a significant impact on fire over most of Asia and Africa but is important in explaining fire over < 22% of Europe and Australia. Increasing population density is associated with both increased and decreased in fire. The nature of the relationship depends on land-use: increasing population density is associated with increased burned are in rangelands but with decreased burned area in croplands. Overall, the relationship between population density and burned area is non-monotonic: burned area initially increases with population density and then decreases when population density exceeds a threshold. These thresholds vary regionally. Our study contributes to improved understanding of how human activities relate to burned area, and should contribute to a better estimate of atmospheric emissions from biomass burning.

  8. Relationships between Human Population Density and Burned Area at Continental and Global Scales

    PubMed Central

    Bistinas, Ioannis; Oom, Duarte; Sá, Ana C. L.; Harrison, Sandy P.; Prentice, I. Colin; Pereira, José M. C.

    2013-01-01

    We explore the large spatial variation in the relationship between population density and burned area, using continental-scale Geographically Weighted Regression (GWR) based on 13 years of satellite-derived burned area maps from the global fire emissions database (GFED) and the human population density from the gridded population of the world (GPW 2005). Significant relationships are observed over 51.5% of the global land area, and the area affected varies from continent to continent: population density has a significant impact on fire over most of Asia and Africa but is important in explaining fire over < 22% of Europe and Australia. Increasing population density is associated with both increased and decreased in fire. The nature of the relationship depends on land-use: increasing population density is associated with increased burned are in rangelands but with decreased burned area in croplands. Overall, the relationship between population density and burned area is non-monotonic: burned area initially increases with population density and then decreases when population density exceeds a threshold. These thresholds vary regionally. Our study contributes to improved understanding of how human activities relate to burned area, and should contribute to a better estimate of atmospheric emissions from biomass burning. PMID:24358108

  9. A Review of the Current Status of Relevant Zoonotic Pathogens in Wild Swine (Sus scrofa) Populations: Changes Modulating the Risk of Transmission to Humans.

    PubMed

    Ruiz-Fons, F

    2017-02-01

    Many wild swine populations in different parts of the World have experienced an unprecedented demographic explosion that may result in increased exposure of humans to wild swine zoonotic pathogens. Interactions between humans and wild swine leading to pathogen transmission could come from different ways, being hunters and game professionals the most exposed to acquiring infections from wild swine. However, increasing human settlements in semi-natural areas, outdoor activities, socio-economic changes and food habits may increase the rate of exposure to wild swine zoonotic pathogens and to potentially emerging pathogens from wild swine. Frequent and increasing contact rate between humans and wild swine points to an increasing chance of zoonotic pathogens arising from wild swine to be transmitted to humans. Whether this frequent contact could lead to new zoonotic pathogens emerging from wild swine to cause human epidemics or emerging disease outbreaks is difficult to predict, and assessment should be based on thorough epidemiologic surveillance. Additionally, several gaps in knowledge on wild swine global population dynamics trends and wild swine-zoonotic pathogen interactions should be addressed to correctly assess the potential role of wild swine in the emergence of diseases in humans. In this work, viruses such as hepatitis E virus, Japanese encephalitis virus, Influenza virus and Nipah virus, and bacteria such as Salmonella spp., Shiga toxin-producing Escherichia coli, Campylobacter spp. and Leptospira spp. have been identified as the most prone to be transmitted from wild swine to humans on the basis of geographic spread in wild swine populations worldwide, pathogen circulation rates in wild swine populations, wild swine population trends in endemic areas, susceptibility of humans to infection, transmissibility from wild swine to humans and existing evidence of wild swine-human transmission events. © 2015 Blackwell Verlag GmbH.

  10. The evolution of human mobility based on the public goods game

    NASA Astrophysics Data System (ADS)

    Yan, Shiqing

    2017-07-01

    We explore the evolution of human mobility behavior based on public goods game. By using mean field method, the population distribution in different regions is theoretical calculated. Numerical simulation results show that the correlation between the region's degree and its final population is not significant under a larger human migration rate. Human mobility could effectively promote cooperative behavior and the population balance of different regions. Therefore, encouraging individuals to migrate may increase the total benefits of the whole society. Moreover, increasing the cooperation cost could reduce the number of cooperators, and that would happen to the correlation between the region's degree and its final population. The results indicate the total population could not dramatically rise with the region's degree under an unfair society.

  11. Human Disturbance Influences Reproductive Success and Growth Rate in California Sea Lions (Zalophus californianus)

    PubMed Central

    French, Susannah S.; González-Suárez, Manuela; Young, Julie K.; Durham, Susan; Gerber, Leah R.

    2011-01-01

    The environment is currently undergoing changes at both global (e.g., climate change) and local (e.g., tourism, pollution, habitat modification) scales that have the capacity to affect the viability of animal and plant populations. Many of these changes, such as human disturbance, have an anthropogenic origin and therefore may be mitigated by management action. To do so requires an understanding of the impact of human activities and changing environmental conditions on population dynamics. We investigated the influence of human activity on important life history parameters (reproductive rate, and body condition, and growth rate of neonate pups) for California sea lions (Zalophus californianus) in the Gulf of California, Mexico. Increased human presence was associated with lower reproductive rates, which translated into reduced long-term population growth rates and suggested that human activities are a disturbance that could lead to population declines. We also observed higher body growth rates in pups with increased exposure to humans. Increased growth rates in pups may reflect a density dependent response to declining reproductive rates (e.g., decreased competition for resources). Our results highlight the potentially complex changes in life history parameters that may result from human disturbance, and their implication for population dynamics. We recommend careful monitoring of human activities in the Gulf of California and emphasize the importance of management strategies that explicitly consider the potential impact of human activities such as ecotourism on vertebrate populations. PMID:21436887

  12. Human population, grasshopper and plant species richness in European countries

    NASA Astrophysics Data System (ADS)

    Steck, Claude E.; Pautasso, Marco

    2008-11-01

    Surprisingly, several studies over large scales have reported a positive spatial correlation of people and biodiversity. This pattern has important implications for conservation and has been documented for well studied taxa such as plants, amphibians, reptiles, birds and mammals. However, it is unknown whether the pattern applies also to invertebrates other than butterflies and more work is needed to establish whether the species-people relationship is explained by both variables correlating with other environmental factors. We studied whether grasshopper species richness (Orthoptera, suborder Caelifera) is related to human population size in European countries. As expected, the number of Caelifera species increases significantly with increasing human population size. But this is not the case when controlling for country area, latitude and number of plant species. Variations in Caelifera species richness are primarily associated with variations in plant species richness. Caelifera species richness also increases with decreasing mean annual precipitation, Gross Domestic Product per capita (used as an indicator for economic development) and net fertility rate of the human population. Our analysis confirms the hypothesis that the broad-scale human population-biodiversity correlations can be explained by concurrent variations in factors other than human population size such as plant species richness, environmental productivity, or habitat heterogeneity. Nonetheless, more populated countries in Europe still have more Caelifera species than less populated countries and this poses a particular challenge for conservation.

  13. Declining human population but increasing residential development around protected areas in Puerto Rico

    Treesearch

    J. Castro-Prieto; S. Martinuzzi; V.C. Radeloff; D.P. Helmers; M. Quiñones; W.A. Gould

    2017-01-01

    Increasing residential development around protected areas is a major threat for protected areas worldwide, and human population growth is often the most important cause. However, population is decreasing in many regions as a result of socio-economic changes, and it is unclear how residential development around protected areas is affected in these situations. We...

  14. Comparative Demography of an At-Risk African Elephant Population

    PubMed Central

    Wittemyer, George; Daballen, David; Douglas-Hamilton, Iain

    2013-01-01

    Knowledge of population processes across various ecological and management settings offers important insights for species conservation and life history. In regard to its ecological role, charisma and threats from human impacts, African elephants are of high conservation concern and, as a result, are the focus of numerous studies across various contexts. Here, demographic data from an individually based study of 934 African elephants in Samburu, Kenya were summarized, providing detailed inspection of the population processes experienced by the population over a fourteen year period (including the repercussions of recent increases in illegal killing). These data were compared with those from populations inhabiting a spectrum of xeric to mesic ecosystems with variable human impacts. In relation to variability in climate and human impacts (causing up to 50% of recorded deaths among adults), annual mortality in Samburu fluctuated between 1 and 14% and, unrelatedly, natality between 2 and 14% driving annual population increases and decreases. Survivorship in Samburu was significantly lower than other populations with age-specific data even during periods of low illegal killing by humans, resulting in relatively low life expectancy of males (18.9 years) and females (21.8 years). Fecundity (primiparous age and inter-calf interval) were similar to those reported in other human impacted or recovering populations, and significantly greater than that of comparable stable populations. This suggests reproductive effort of African savanna elephants increases in relation to increased mortality (and resulting ecological ramifications) as predicted by life history theory. Further comparison across populations indicated that elongated inter-calf intervals and older ages of reproductive onset were related to age structure and density, and likely influenced by ecological conditions. This study provides detailed empirical data on elephant population dynamics strongly influenced by human impacts (laying the foundation for modeling approaches), supporting predictions of evolutionary theory regarding demographic responses to ecological processes. PMID:23341984

  15. Comparative demography of an at-risk African elephant population.

    PubMed

    Wittemyer, George; Daballen, David; Douglas-Hamilton, Iain

    2013-01-01

    Knowledge of population processes across various ecological and management settings offers important insights for species conservation and life history. In regard to its ecological role, charisma and threats from human impacts, African elephants are of high conservation concern and, as a result, are the focus of numerous studies across various contexts. Here, demographic data from an individually based study of 934 African elephants in Samburu, Kenya were summarized, providing detailed inspection of the population processes experienced by the population over a fourteen year period (including the repercussions of recent increases in illegal killing). These data were compared with those from populations inhabiting a spectrum of xeric to mesic ecosystems with variable human impacts. In relation to variability in climate and human impacts (causing up to 50% of recorded deaths among adults), annual mortality in Samburu fluctuated between 1 and 14% and, unrelatedly, natality between 2 and 14% driving annual population increases and decreases. Survivorship in Samburu was significantly lower than other populations with age-specific data even during periods of low illegal killing by humans, resulting in relatively low life expectancy of males (18.9 years) and females (21.8 years). Fecundity (primiparous age and inter-calf interval) were similar to those reported in other human impacted or recovering populations, and significantly greater than that of comparable stable populations. This suggests reproductive effort of African savanna elephants increases in relation to increased mortality (and resulting ecological ramifications) as predicted by life history theory. Further comparison across populations indicated that elongated inter-calf intervals and older ages of reproductive onset were related to age structure and density, and likely influenced by ecological conditions. This study provides detailed empirical data on elephant population dynamics strongly influenced by human impacts (laying the foundation for modeling approaches), supporting predictions of evolutionary theory regarding demographic responses to ecological processes.

  16. Wetland habitats for wildlife of the Chesapeake Bay

    USGS Publications Warehouse

    Perry, M.C.; Majumdar, S.K.; Miller, E.W.; Brenner, Fred J.

    1998-01-01

    The wetlands of Chesapeake Bay have provided the vital habitats that have sustained the impressive wildlife populations that have brought international fame to the Bay. As these wetland habitats decrease in quantity and quality we will continue to see the decline in the wildlife populations that started when European settlers first came to this continent. These declines have accelerated significantly in this century. As the human population continues to increase in the Bay watershed, one can expect that wetland habitats will continue to decline, resulting in declines in species diversity and population numbers. Although federal, state, and local governments are striving for 'no net loss' of wetlands, the results to date are not encouraging. It is unrealistic to believe that human populations and associated development can continue to increase and not adversely affect the wetland resources of the Bay. Restrictions on human population growth in the Chesapeake area is clearly the best way to protect wetland habitats and the wildlife that are dependent on these habitats. In addition, there should be more aggressive approaches to protect wetland habitats from continued perturbations from humans. More sanctuary areas should be created and there should be greater use of enhancement and management techniques that will benefit the full complement of species that potentially exist in these wetlands. The present trend in wetland loss can be expected to continue as human populations increase with resultant increases in roads, shopping malls, and housing developments. Creation of habitat for mitigation of these losses will not result in 'no net loss'. More innovative approaches should be employed to reverse the long-term trend in wetland loss by humans.

  17. The Importance of Human Ecology at the Threshold of the Next Millennium: How Can Population Growth Be Stopped?

    NASA Astrophysics Data System (ADS)

    Nentwig, W.

    Ecology is defined as the set of complex interactions between the biotic and abiotic environments. Human ecology concerns principally the population ecology "only" of Homo sapiens, but it also includes all aspects of global ecology because humans are the most important species. Human demography is characterized by a recent decline in mortality and fertility rates. These demographic transitions have largely been completed in industrialized countries, but not in the 140 developing countries. Approximately 100 countries are following the same demographic pattern as industrialized countries, however with a time delay of several generations. China has effectively reduced its population increase by means that would be unacceptable in Western democracies. Some 44 developing countries still show increasing population growth and no detectable demographic transition in birth rate. Thus one part of the world shows limited (and, in the long run, shrinking) population growth, and another continues with a strong increase. All populations are limited in their development by their sustainability by their environment, for example, food and energy resources, and the extent of pollution which the use of these resources produces. It is argued that in the case of human population the limits of sustainability have already been reached with the 6 billion humans alive today, since at least 20% of these suffer from hunger, natural resources are overexploited, and biodiversity is threatened. In the coming 200years it is more likely that the total population will substantially oscillate rather than approach the predicted 12 billion. The most important goal of human ecology should therefore be to slow population growth as far as possible.

  18. Some macroeconomic aspects of global population aging.

    PubMed

    Lee, Ronald; Mason, Andrew

    2010-01-01

    Across the demographic transition, declining mortality followed by declining fertility produces decades of rising support ratios as child dependency falls. These improving support ratios raise per capita consumption, other things equal, but eventually deteriorate as the population ages. Population aging and the forces leading to it can produce not only frightening declines in support ratios but also very substantial increases in productivity and per capita income by raising investment in physical and human capital. Longer life, lower fertility, and population aging all raise the demand for wealth needed to provide for old-age consumption. This leads to increased capital per worker even as aggregate saving rates fall. However, capital per worker may not rise if the increased demand for wealth is satisfied by increased familial or public pension transfers to the elderly. Thus, institutions and policies matter for the consequences of population aging. The accumulation of human capital also varies across the transition. Lower fertility and mortality are associated with higher human capital investment per child, also raising labor productivity. Together, the positive changes due to human and physical capital accumulation will likely outweigh the problems of declining support ratios. We draw on estimates and analyses from the National Transfer Accounts project to illustrate and quantify these points.

  19. A stochastic step model of replicative senescence explains ROS production rate in ageing cell populations.

    PubMed

    Lawless, Conor; Jurk, Diana; Gillespie, Colin S; Shanley, Daryl; Saretzki, Gabriele; von Zglinicki, Thomas; Passos, João F

    2012-01-01

    Increases in cellular Reactive Oxygen Species (ROS) concentration with age have been observed repeatedly in mammalian tissues. Concomitant increases in the proportion of replicatively senescent cells in ageing mammalian tissues have also been observed. Populations of mitotic human fibroblasts cultured in vitro, undergoing transition from proliferation competence to replicative senescence are useful models of ageing human tissues. Similar exponential increases in ROS with age have been observed in this model system. Tracking individual cells in dividing populations is difficult, and so the vast majority of observations have been cross-sectional, at the population level, rather than longitudinal observations of individual cells.One possible explanation for these observations is an exponential increase in ROS in individual fibroblasts with time (e.g. resulting from a vicious cycle between cellular ROS and damage). However, we demonstrate an alternative, simple hypothesis, equally consistent with these observations which does not depend on any gradual increase in ROS concentration: the Stochastic Step Model of Replicative Senescence (SSMRS). We also demonstrate that, consistent with the SSMRS, neither proliferation-competent human fibroblasts of any age, nor populations of hTERT overexpressing human fibroblasts passaged beyond the Hayflick limit, display high ROS concentrations. We conclude that longitudinal studies of single cells and their lineages are now required for testing hypotheses about roles and mechanisms of ROS increase during replicative senescence.

  20. A Stochastic Step Model of Replicative Senescence Explains ROS Production Rate in Ageing Cell Populations

    PubMed Central

    Lawless, Conor; Jurk, Diana; Gillespie, Colin S.; Shanley, Daryl; Saretzki, Gabriele; von Zglinicki, Thomas; Passos, João F.

    2012-01-01

    Increases in cellular Reactive Oxygen Species (ROS) concentration with age have been observed repeatedly in mammalian tissues. Concomitant increases in the proportion of replicatively senescent cells in ageing mammalian tissues have also been observed. Populations of mitotic human fibroblasts cultured in vitro, undergoing transition from proliferation competence to replicative senescence are useful models of ageing human tissues. Similar exponential increases in ROS with age have been observed in this model system. Tracking individual cells in dividing populations is difficult, and so the vast majority of observations have been cross-sectional, at the population level, rather than longitudinal observations of individual cells. One possible explanation for these observations is an exponential increase in ROS in individual fibroblasts with time (e.g. resulting from a vicious cycle between cellular ROS and damage). However, we demonstrate an alternative, simple hypothesis, equally consistent with these observations which does not depend on any gradual increase in ROS concentration: the Stochastic Step Model of Replicative Senescence (SSMRS). We also demonstrate that, consistent with the SSMRS, neither proliferation-competent human fibroblasts of any age, nor populations of hTERT overexpressing human fibroblasts passaged beyond the Hayflick limit, display high ROS concentrations. We conclude that longitudinal studies of single cells and their lineages are now required for testing hypotheses about roles and mechanisms of ROS increase during replicative senescence. PMID:22359661

  1. Hunting as a management tool? Cougar-human conflict is positively related to trophy hunting.

    PubMed

    Teichman, Kristine J; Cristescu, Bogdan; Darimont, Chris T

    2016-10-11

    Overexploitation and persecution of large carnivores resulting from conflict with humans comprise major causes of declines worldwide. Although little is known about the interplay between these mortality types, hunting of predators remains a common management strategy aimed at reducing predator-human conflict. Emerging theory and data, however, caution that such policy can alter the age structure of populations, triggering increased conflict in which conflict-prone juveniles are involved. Using a 30-year dataset on human-caused cougar (Puma concolor) kills in British Columbia (BC), Canada, we examined relationships between hunter-caused and conflict-associated mortality. Individuals that were killed via conflict with humans were younger than hunted cougars. Accounting for human density and habitat productivity, human hunting pressure during or before the year of conflict comprised the most important variables. Both were associated with increased male cougar-human conflict. Moreover, in each of five regions assessed, conflict was higher with increased human hunting pressure for at least one cougar sex. Although only providing correlative evidence, such patterns over large geographic and temporal scales suggest that alternative approaches to conflict mitigation might yield more effective outcomes for humans as well as cougar populations and the individuals within populations.

  2. Projecting population change in the interior Columbia River Basin.

    Treesearch

    Stephen F. McCool; Richard W. Haynes

    1996-01-01

    Management of ecosystems requires projecting the human population for a biologically significant timeframe, because the impacts of potential alternative ecosystem management strategies will differ depending on the size, location, and expectations of the human population. Increases since 1990 in the net migration rates are changing the expectations for projections of...

  3. Out of Africa: modern human origins special feature: explaining worldwide patterns of human genetic variation using a coalescent-based serial founder model of migration outward from Africa.

    PubMed

    DeGiorgio, Michael; Jakobsson, Mattias; Rosenberg, Noah A

    2009-09-22

    Studies of worldwide human variation have discovered three trends in summary statistics as a function of increasing geographic distance from East Africa: a decrease in heterozygosity, an increase in linkage disequilibrium (LD), and a decrease in the slope of the ancestral allele frequency spectrum. Forward simulations of unlinked loci have shown that the decline in heterozygosity can be described by a serial founder model, in which populations migrate outward from Africa through a process where each of a series of populations is formed from a subset of the previous population in the outward expansion. Here, we extend this approach by developing a retrospective coalescent-based serial founder model that incorporates linked loci. Our model both recovers the observed decline in heterozygosity with increasing distance from Africa and produces the patterns observed in LD and the ancestral allele frequency spectrum. Surprisingly, although migration between neighboring populations and limited admixture between modern and archaic humans can be accommodated in the model while continuing to explain the three trends, a competing model in which a wave of outward modern human migration expands into a series of preexisting archaic populations produces nearly opposite patterns to those observed in the data. We conclude by developing a simpler model to illustrate that the feature that permits the serial founder model but not the archaic persistence model to explain the three trends observed with increasing distance from Africa is its incorporation of a cumulative effect of genetic drift as humans colonized the world.

  4. Socio-Economic Instability and the Scaling of Energy Use with Population Size

    PubMed Central

    DeLong, John P.; Burger, Oskar

    2015-01-01

    The size of the human population is relevant to the development of a sustainable world, yet the forces setting growth or declines in the human population are poorly understood. Generally, population growth rates depend on whether new individuals compete for the same energy (leading to Malthusian or density-dependent growth) or help to generate new energy (leading to exponential and super-exponential growth). It has been hypothesized that exponential and super-exponential growth in humans has resulted from carrying capacity, which is in part determined by energy availability, keeping pace with or exceeding the rate of population growth. We evaluated the relationship between energy use and population size for countries with long records of both and the world as a whole to assess whether energy yields are consistent with the idea of an increasing carrying capacity. We find that on average energy use has indeed kept pace with population size over long time periods. We also show, however, that the energy-population scaling exponent plummets during, and its temporal variability increases preceding, periods of social, political, technological, and environmental change. We suggest that efforts to increase the reliability of future energy yields may be essential for stabilizing both population growth and the global socio-economic system. PMID:26091499

  5. Socio-Economic Instability and the Scaling of Energy Use with Population Size.

    PubMed

    DeLong, John P; Burger, Oskar

    2015-01-01

    The size of the human population is relevant to the development of a sustainable world, yet the forces setting growth or declines in the human population are poorly understood. Generally, population growth rates depend on whether new individuals compete for the same energy (leading to Malthusian or density-dependent growth) or help to generate new energy (leading to exponential and super-exponential growth). It has been hypothesized that exponential and super-exponential growth in humans has resulted from carrying capacity, which is in part determined by energy availability, keeping pace with or exceeding the rate of population growth. We evaluated the relationship between energy use and population size for countries with long records of both and the world as a whole to assess whether energy yields are consistent with the idea of an increasing carrying capacity. We find that on average energy use has indeed kept pace with population size over long time periods. We also show, however, that the energy-population scaling exponent plummets during, and its temporal variability increases preceding, periods of social, political, technological, and environmental change. We suggest that efforts to increase the reliability of future energy yields may be essential for stabilizing both population growth and the global socio-economic system.

  6. Insights into Modern Human Prehistory Using Ancient Genomes.

    PubMed

    Yang, Melinda A; Fu, Qiaomei

    2018-03-01

    The genetic relationship of past modern humans to today's populations and each other was largely unknown until recently, when advances in ancient DNA sequencing allowed for unprecedented analysis of the genomes of these early people. These ancient genomes reveal new insights into human prehistory not always observed studying present-day populations, including greater details on the genetic diversity, population structure, and gene flow that characterized past human populations, particularly in early Eurasia, as well as increased insight on the relationship between archaic and modern humans. Here, we review genetic studies on ∼45000- to 7500-year-old individuals associated with mainly preagricultural cultures found in Eurasia, the Americas, and Africa. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Population and prehistory I: Food-dependent population growth in constant environments.

    PubMed

    Lee, Charlotte T; Tuljapurkar, Shripad

    2008-06-01

    We present a demographic model that describes the feedbacks between food supply, human mortality and fertility rates, and labor availability in expanding populations, where arable land area is not limiting. This model provides a quantitative framework to describe how environment, technology, and culture interact to influence the fates of preindustrial agricultural populations. We present equilibrium conditions and derive approximations for the equilibrium population growth rate, food availability, and other food-dependent measures of population well-being. We examine how the approximations respond to environmental changes and to human choices, and find that the impact of environmental quality depends upon whether it manifests through agricultural yield or maximum (food-independent) survival rates. Human choices can complement or offset environmental effects: greater labor investments increase both population growth and well-being, and therefore can counteract lower agricultural yield, while fertility control decreases the growth rate but can increase or decrease well-being. Finally we establish equilibrium stability criteria, and argue that the potential for loss of local stability at low population growth rates could have important consequences for populations that suffer significant environmental or demographic shocks.

  8. Bear mauling: a descriptive review.

    PubMed

    Dieter, R A; Dieter, D L; Dieter, R A; Forbes, B

    2001-11-01

    Provide a descriptive review of bear and human interactions in the United States. Descriptive review. The bear population in the United States includes the grizzly bear, the polar bear, and the black bear, including the glacier phase or blue bear. As the human population grew and remote or wilderness access improved, the bear population suffered both in total numbers and safe habitat. Conservation efforts, such as hunting restrictions and habitat enhancement, have helped to increase the total numbers of bears on the North American continent. The chance of a human encountering a bear increases as the remote bear territory diminishes. Bear incidents are widely publicized, though few serious incidents occur. The authors have direct knowledge of these bear-human encounters in Alaska. Serious human injuries from black bears, or maulings, including fatalities are uncommon. Grizzly bears when trapped or stimulated may be very dangerous. The polar bear sees everything that moves or has color, as potential food, and therefore, will attack seemingly unprovoked. The chance of a human encountering a bear increases as the remote bear territory diminishes. Bear incidents are widely publicized, though few serious incidents occur.

  9. Global effects of local human population density and distance to markets on the condition of coral reef fisheries.

    PubMed

    Cinner, Joshua E; Graham, Nicholas A J; Huchery, Cindy; Macneil, M Aaron

    2013-06-01

    Coral reef fisheries support the livelihoods of millions of people but have been severely and negatively affected by anthropogenic activities. We conducted a systematic review of published data on the biomass of coral reef fishes to explore how the condition of reef fisheries is related to the density of local human populations, proximity of the reef to markets, and key environmental variables (including broad geomorphologic reef type, reef area, and net productivity). When only population density and environmental covariates were considered, high variability in fisheries conditions at low human population densities resulted in relatively weak explanatory models. The presence or absence of human settlements, habitat type, and distance to fish markets provided a much stronger explanatory model for the condition of reef fisheries. Fish biomass remained relatively low within 14 km of markets, then biomass increased exponentially as distance from reefs to markets increased. Our results suggest the need for an increased science and policy focus on markets as both a key driver of the condition of reef fisheries and a potential source of solutions. © 2012 Society for Conservation Biology.

  10. Human Population: Fundamentals of Growth and Change.

    ERIC Educational Resources Information Center

    Stauffer, Cheryl Lynn, Ed.

    This booklet focuses on eight elements of population dynamics: "Population Growth and Distribution"; "Natural Increase and Future Growth"; "Effect of Migration on Population Growth"; "Three Patterns of Population Change"; "Patterns of World Urbanization"; "The Status of Women";…

  11. Is urbanisation scrambling the genetic structure of human populations? A case study

    PubMed Central

    Ashrafian-Bonab, Maziar; Handley, Lori Lawson; Balloux, François

    2007-01-01

    Recent population expansion and increased migration linked to urbanisation are assumed to be eroding the genetic structure of human populations. We investigated change in population structure over three generations by analysing both demographic and mitochondrial DNA (mtDNA) data from a random sample of 2351 men from twenty-two Iranian populations. Potential changes in genetic diversity (θ) and genetic distance (FST) over the last three generations were analysed by assigning mtDNA sequences to populations based on the individual's place of birth or that of their mother or grandmother. Despite the fact that several areas included cities of over one million inhabitants, we detected no change in genetic diversity, and only a small decrease in population structure, except in the capital city (Tehran), which was characterised by massive immigration, increased θ and a large decrease in FST over time. Our results suggest that recent erosion of human population structure might not be as important as previously thought, except in some large conurbations, and this clearly has important implications for future sampling strategies. PMID:17106453

  12. Potential future scenarios for Australia's native biodiversity given on-going increases in human population.

    PubMed

    Pepper, D A; Lada, Hania; Thomson, James R; Bakar, K Shuvo; Lake, P S; Mac Nally, Ralph

    2017-01-15

    Most natural assets, including native biodiversity (our focus), are under increasing threat from direct (loss of habitat, hunting) and indirect (climate change) human actions. Most human impacts arise from increasing human populations coupled with rises in per capita resource use. The rates of change of human actions generally outpace those to which the biota can respond or adapt. If we are to maintain native biodiversity, then we must develop ways to envisage how the biota may be affected over the next several decades to guide management and policy responses. We consider the future for Australia's native biodiversity in the context of two assumptions. First, the human population in Australia will be 40million by 2050, which has been mooted by federal government agencies. Second, greenhouse gas emissions will track the highest rates considered by the Intergovernmental Panel on Climate Change. The scenarios are based on major drivers of change, which were constructed from seven key drivers of change pertinent to native biodiversity. Five scenarios deal with differing distributions of the human population driven by uncertainties in climate change and in the human responses to climate change. Other scenarios are governed largely by global change and explore different rates of resource use, unprecedented rates of technological change, capabilities and societal values. A narrative for each scenario is provided. The set of scenarios spans a wide range of possible future paths for Australia, with different implications for the future of native biodiversity. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Correlates of bushmeat in markets and depletion of wildlife.

    PubMed

    Fa, John E; Olivero, Jesus; Farfán, Miguel Á; Márquez, Ana L; Duarte, Jesús; Nackoney, Janet; Hall, Amy; Dupain, Jef; Seymour, Sarah; Johnson, Paul J; Macdonald, David W; Real, Raimundo; Vargas, Juan M

    2015-06-01

    We used data on number of carcasses of wildlife species sold in 79 bushmeat markets in a region of Nigeria and Cameroon to assess whether species composition of a market could be explained by anthropogenic pressures and environmental variables around each market. More than 45 mammal species from 9 orders were traded across all markets; mostly ungulates and rodents. For each market, we determined median body mass, species diversity (game diversity), and taxa that were principal contributors to the total number of carcasses for sale (game dominance). Human population density in surrounding areas was significantly and negatively related to the percentage ungulates and primates sold in markets and significantly and positively related to the proportion of rodents. The proportion of carnivores sold was higher in markets with high human population densities. Proportion of small-bodied mammals (<1 kg) sold in markets increased as human population density increased, but proportion of large-bodied mammals (>10 kg) decreased as human population density increased. We calculated an index of game depletion (GDI) for each market from the sum of the total number of carcasses traded per annum and species, weighted by the intrinsic rate of natural increase (rmax ) of each species, divided by individuals traded in a market. The GDI of a market increased as the proportion of fast-reproducing species (highest rmax ) increased and as the representation of species with lowest rmax (slow-reproducing) decreased. The best explanatory factor for a market's GDI was anthropogenic pressure-road density, human settlements with >3000 inhabitants, and nonforest vegetation. High and low GDI were significantly differentiated by human density and human settlements with >3000 inhabitants. Our results provided empirical evidence that human activity is correlated with more depleted bushmeat faunas and can be used as a proxy to determine areas in need of conservation action. © 2015 Society for Conservation Biology.

  14. Genomic Approach to Understand the Association of DNA Repair with Longevity and Healthy Aging Using Genomic Databases of Oldest-Old Population

    PubMed Central

    Kim, Hyun Soo

    2018-01-01

    Aged population is increasing worldwide due to the aging process that is inevitable. Accordingly, longevity and healthy aging have been spotlighted to promote social contribution of aged population. Many studies in the past few decades have reported the process of aging and longevity, emphasizing the importance of maintaining genomic stability in exceptionally long-lived population. Underlying reason of longevity remains unclear due to its complexity involving multiple factors. With advances in sequencing technology and human genome-associated approaches, studies based on population-based genomic studies are increasing. In this review, we summarize recent longevity and healthy aging studies of human population focusing on DNA repair as a major factor in maintaining genome integrity. To keep pace with recent growth in genomic research, aging- and longevity-associated genomic databases are also briefly introduced. To suggest novel approaches to investigate longevity-associated genetic variants related to DNA repair using genomic databases, gene set analysis was conducted, focusing on DNA repair- and longevity-associated genes. Their biological networks were additionally analyzed to grasp major factors containing genetic variants of human longevity and healthy aging in DNA repair mechanisms. In summary, this review emphasizes DNA repair activity in human longevity and suggests approach to conduct DNA repair-associated genomic study on human healthy aging.

  15. Meta-Analysis of Relationships between Human Offtake, Total Mortality and Population Dynamics of Gray Wolves (Canis lupus)

    PubMed Central

    Creel, Scott; Rotella, Jay J.

    2010-01-01

    Following the growth and geographic expansion of wolf (Canis lupus) populations reintroduced to Yellowstone National Park and central Idaho in 1995–1996, Rocky Mountain wolves were removed from the endangered species list in May 2009. Idaho and Montana immediately established hunting seasons with quotas equaling 20% of the regional wolf population. Combining hunting with predator control, 37.1% of Montana and Idaho wolves were killed in the year of delisting. Hunting and predator control are well-established methods to broaden societal acceptance of large carnivores, but it is unprecedented for a species to move so rapidly from protection under the Endangered Species Act to heavy direct harvest, and it is important to use all available data to assess the likely consequences of these changes in policy. For wolves, it is widely argued that human offtake has little effect on total mortality rates, so that a harvest of 28–50% per year can be sustained. Using previously published data from 21 North American wolf populations, we related total annual mortality and population growth to annual human offtake. Contrary to current conventional wisdom, there was a strong association between human offtake and total mortality rates across North American wolf populations. Human offtake was associated with a strongly additive or super-additive increase in total mortality. Population growth declined as human offtake increased, even at low rates of offtake. Finally, wolf populations declined with harvests substantially lower than the thresholds identified in current state and federal policies. These results should help to inform management of Rocky Mountain wolves. PMID:20927363

  16. Meta-analysis of relationships between human offtake, total mortality and population dynamics of gray wolves (Canis lupus).

    PubMed

    Creel, Scott; Rotella, Jay J

    2010-09-29

    Following the growth and geographic expansion of wolf (Canis lupus) populations reintroduced to Yellowstone National Park and central Idaho in 1995-1996, Rocky Mountain wolves were removed from the endangered species list in May 2009. Idaho and Montana immediately established hunting seasons with quotas equaling 20% of the regional wolf population. Combining hunting with predator control, 37.1% of Montana and Idaho wolves were killed in the year of delisting. Hunting and predator control are well-established methods to broaden societal acceptance of large carnivores, but it is unprecedented for a species to move so rapidly from protection under the Endangered Species Act to heavy direct harvest, and it is important to use all available data to assess the likely consequences of these changes in policy. For wolves, it is widely argued that human offtake has little effect on total mortality rates, so that a harvest of 28-50% per year can be sustained. Using previously published data from 21 North American wolf populations, we related total annual mortality and population growth to annual human offtake. Contrary to current conventional wisdom, there was a strong association between human offtake and total mortality rates across North American wolf populations. Human offtake was associated with a strongly additive or super-additive increase in total mortality. Population growth declined as human offtake increased, even at low rates of offtake. Finally, wolf populations declined with harvests substantially lower than the thresholds identified in current state and federal policies. These results should help to inform management of Rocky Mountain wolves.

  17. Monitoring population and environmental parameters of invasive mosquito species in Europe

    PubMed Central

    2014-01-01

    To enable a better understanding of the overwhelming alterations in the invasive mosquito species (IMS), methodical insight into the population and environmental factors that govern the IMS and pathogen adaptations are essential. There are numerous ways of estimating mosquito populations, and usually these describe developmental and life-history parameters. The key population parameters that should be considered during the surveillance of invasive mosquito species are: (1) population size and dynamics during the season, (2) longevity, (3) biting behaviour, and (4) dispersal capacity. Knowledge of these parameters coupled with vector competence may help to determine the vectorial capacity of IMS and basic disease reproduction number (R0) to support mosquito borne disease (MBD) risk assessment. Similarly, environmental factors include availability and type of larval breeding containers, climate change, environmental change, human population density, increased human travel and goods transport, changes in living, agricultural and farming habits (e.g. land use), and reduction of resources in the life cycle of mosquitoes by interventions (e.g. source reduction of aquatic habitats). Human population distributions, urbanisation, and human population movement are the key behavioural factors in most IMS-transmitted diseases. Anthropogenic issues are related to the global spread of MBD such as the introduction, reintroduction, circulation of IMS and increased exposure to humans from infected mosquito bites. This review addresses the population and environmental factors underlying the growing changes in IMS populations in Europe and confers the parameters selected by criteria of their applicability. In addition, overview of the commonly used and newly developed tools for their monitoring is provided. PMID:24739334

  18. ASSESSING RISKS TO WILDLIFE POPULATIONS FROM MULTIPLE STRESSORS: OVERVIEW OF PROBLEM AND RESEARCH NEEDS

    EPA Science Inventory

    Wildlife populations are experiencing increasing pressure from human-induced changes in the landscape. Stressors including agricultural and urban land use, introduced invasive and exotic species, nutrient enrichment, direct human disturbance, and toxic chemicals directly or indi...

  19. Commonalities in Development of Pure Breeds and Population Isolates Revealed in the Genome of the Sardinian Fonni's Dog.

    PubMed

    Dreger, Dayna L; Davis, Brian W; Cocco, Raffaella; Sechi, Sara; Di Cerbo, Alessandro; Parker, Heidi G; Polli, Michele; Marelli, Stefano P; Crepaldi, Paola; Ostrander, Elaine A

    2016-10-01

    The island inhabitants of Sardinia have long been a focus for studies of complex human traits due to their unique ancestral background and population isolation reflecting geographic and cultural restriction. Population isolates share decreased genomic diversity, increased linkage disequilibrium, and increased inbreeding coefficients. In many regions, dogs and humans have been exposed to the same natural and artificial forces of environment, growth, and migration. Distinct dog breeds have arisen through human-driven selection of characteristics to meet an ideal standard of appearance and function. The Fonni's Dog, an endemic dog population on Sardinia, has not been subjected to an intensive system of artificial selection, but rather has developed alongside the human population of Sardinia, influenced by geographic isolation and unregulated selection based on its environmental adaptation and aptitude for owner-desired behaviors. Through analysis of 28 dog breeds, represented with whole-genome sequences from 13 dogs and ∼170,000 genome-wide single nucleotide variants from 155 dogs, we have produced a genomic illustration of the Fonni's Dog. Genomic patterns confirm within-breed similarity, while population and demographic analyses provide spatial identity of Fonni's Dog to other Mediterranean breeds. Investigation of admixture and fixation indices reveals insights into the involvement of Fonni's Dogs in breed development throughout the Mediterranean. We describe how characteristics of population isolates are reflected in dog breeds that have undergone artificial selection, and are mirrored in the Fonni's Dog through traditional isolating factors that affect human populations. Lastly, we show that the genetic history of Fonni's Dog parallels demographic events in local human populations. Copyright © 2016 by the Genetics Society of America.

  20. Commonalities in Development of Pure Breeds and Population Isolates Revealed in the Genome of the Sardinian Fonni's Dog

    PubMed Central

    Dreger, Dayna L.; Davis, Brian W.; Cocco, Raffaella; Sechi, Sara; Di Cerbo, Alessandro; Parker, Heidi G.; Polli, Michele; Marelli, Stefano P.; Crepaldi, Paola; Ostrander, Elaine A.

    2016-01-01

    The island inhabitants of Sardinia have long been a focus for studies of complex human traits due to their unique ancestral background and population isolation reflecting geographic and cultural restriction. Population isolates share decreased genomic diversity, increased linkage disequilibrium, and increased inbreeding coefficients. In many regions, dogs and humans have been exposed to the same natural and artificial forces of environment, growth, and migration. Distinct dog breeds have arisen through human-driven selection of characteristics to meet an ideal standard of appearance and function. The Fonni’s Dog, an endemic dog population on Sardinia, has not been subjected to an intensive system of artificial selection, but rather has developed alongside the human population of Sardinia, influenced by geographic isolation and unregulated selection based on its environmental adaptation and aptitude for owner-desired behaviors. Through analysis of 28 dog breeds, represented with whole-genome sequences from 13 dogs and ∼170,000 genome-wide single nucleotide variants from 155 dogs, we have produced a genomic illustration of the Fonni’s Dog. Genomic patterns confirm within-breed similarity, while population and demographic analyses provide spatial identity of Fonni’s Dog to other Mediterranean breeds. Investigation of admixture and fixation indices reveals insights into the involvement of Fonni’s Dogs in breed development throughout the Mediterranean. We describe how characteristics of population isolates are reflected in dog breeds that have undergone artificial selection, and are mirrored in the Fonni’s Dog through traditional isolating factors that affect human populations. Lastly, we show that the genetic history of Fonni’s Dog parallels demographic events in local human populations. PMID:27519604

  1. Role of Light in Breast Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stevens, Richard G.; Anderson, Larry E.; Michael F. Holick

    1999-06-14

    There is a prima facie reason for studying possible biological effects of light-at-night (LAN) in the laboratory and human health effects in the population at large: LAN from the use of electricity represent exposures in the human environment not previously encountered in human evolution. These LAN exposures are pervasive in industrialized societies, and any adverse health effects from them could result in considerable consequences for the population. In particular, exposures of pregnant women to LAN that might result in increased estrogen exposure in utero to their child may lead to increased tissue mass and increased lifetime risk of breast cancermore » of the child.« less

  2. Impacts of land-use change to ecosystem services

    USGS Publications Warehouse

    Stohlgren, Tom; Holcombe, Tracy R.

    2013-01-01

    Increasing human populations on the landscape and globe coincide with increasing demands for food, energy, and other natural resources, with generally negative impacts to wildlife habitat, air and water quality, and natural scenery. Here we define and describe the impacts of land-use change on ecosystem services – the services that ecosystems provide humans such as filtering air and water, providing food, resources, recreation, and esthetics. We show how the human footprint is rapidly expanding due to population growth, demand for resources, and globalization. Increased trade and transportation has brought all the continents back together, creating new challenges for conserving native species and ecosystems.

  3. A demographic perspective on the Middle to Later Stone Age transition from Nasera rockshelter, Tanzania

    PubMed Central

    Tryon, Christian A.; Faith, J. Tyler

    2016-01-01

    Increased population density is among the proposed drivers of the behavioural changes culminating in the Middle to Later Stone Age (MSA–LSA) transition and human dispersals from East Africa, but reliable archaeological measures of demographic change are lacking. We use Late Pleistocene–Holocene lithic and faunal data from Nasera rockshelter (Tanzania) to show progressive declines in residential mobility—a variable linked to population density—and technological shifts, the latter associated with environmental changes. These data suggest that the MSA–LSA transition is part of a long-term pattern of changes in residential mobility and technology that reflect human responses to increased population density, with dispersals potentially marking a complementary response to larger populations. This article is part of the themed issue ‘Major transitions in human evolution’. PMID:27298469

  4. Nitrogen Leaching Index

    USDA-ARS?s Scientific Manuscript database

    World agricultural production will have to increase significantly during the next few decades to keep up with the increasing demands for food brought about by a growing human population. Increases in agricultural production will be required not only to supply grain for a larger world population, but...

  5. The importance of resident environmental awareness in conservation of urban wildlife populations

    EPA Science Inventory

    The proximity of humans and wildlife to each other along the wildland-urban interface results in constant potential conflict between human activity and wildlife populations. Since 2002, California biologists have observed a drastic increase in carnivore mortalities that are asso...

  6. Population and prehistory II: Space-limited human populations in constant environments

    PubMed Central

    Puleston, Cedric O.; Tuljapurkar, Shripad

    2010-01-01

    We present a population model to examine the forces that determined the quality and quantity of human life in early agricultural societies where cultivable area is limited. The model is driven by the non-linear and interdependent relationships between the age distribution of a population, its behavior and technology, and the nature of its environment. The common currency in the model is the production of food, on which age-specific rates of birth and death depend. There is a single nontrivial equilibrium population at which productivity balances caloric needs. One of the most powerful controls on equilibrium hunger level is fertility control. Gains against hunger are accompanied by decreases in population size. Increasing worker productivity does increase equilibrium population size but does not improve welfare at equilibrium. As a case study we apply the model to the population of a Polynesian valley before European contact. PMID:18598711

  7. Population and prehistory II: space-limited human populations in constant environments.

    PubMed

    Puleston, Cedric O; Tuljapurkar, Shripad

    2008-09-01

    We present a population model to examine the forces that determined the quality and quantity of human life in early agricultural societies where cultivable area is limited. The model is driven by the non-linear and interdependent relationships between the age distribution of a population, its behavior and technology, and the nature of its environment. The common currency in the model is the production of food, on which age-specific rates of birth and death depend. There is a single non-trivial equilibrium population at which productivity balances caloric needs. One of the most powerful controls on equilibrium hunger level is fertility control. Gains against hunger are accompanied by decreases in population size. Increasing worker productivity does increase equilibrium population size but does not improve welfare at equilibrium. As a case study we apply the model to the population of a Polynesian valley before European contact.

  8. Uncanny valley: A preliminary study on the acceptance of Malaysian urban and rural population toward different types of robotic faces

    NASA Astrophysics Data System (ADS)

    Tay, T. T.; Low, Raymond; Loke, H. J.; Chua, Y. L.; Goh, Y. H.

    2018-04-01

    The proliferation of robotic technologies in recent years brings robots closer to humanities. There are many researches on going at various stages of development to bring robots into our homes, schools, nurseries, elderly care centres, offices, hospitals and factories. With recently developed robots having tendency to have appearance which increasingly displaying similarities to household animals and humans, there is a need to study the existence of uncanny valley phenomenon. Generally, the acceptance of people toward robots increases as the robots acquire increasing similarities to human features until a stage where people feel very uncomfortable, eerie, fear and disgust when the robot appearance become almost human like but not yet human. This phenomenon called uncanny valley was first reported by Masahiro Mori. There are numerous researches conducted to measure the existence of uncanny valley in Japan and European countries. However, there is limited research reported on uncanny valley phenomenon in Malaysia so far. In view of the different cultural background and exposure of Malaysian population to robotics technology compared to European or East Asian populations, it is worth to study this phenomenon in Malaysian context. The main aim of this work is to conduct a preliminary study to determine the existence of uncanny valley phenomenon in Malaysian urban and rural populations. It is interesting to find if there are any differences in the acceptance of the two set of populations despite of their differences. Among others the urban and rural populations differ in term of the rate of urbanization and exposure to latest technologies. A set of four interactive robotic faces and an ideal human model representing the fifth robot are used in this study. The robots have features resembling a cute animal, cartoon character, typical robot and human-like. Questionnaire surveys are conducted on respondents from urban and rural populations. Survey data collected are analysed to determine the preferred features in a humanoid robot, the acceptance of respondents toward the robotic faces and the existence of uncanny valley phenomenon. Based on the limited study, it is found that the uncanny valley phenomenon existed in both the Malaysian urban and rural population.

  9. 75 FR 51273 - Expanded Human Immunodeficiency Virus (HIV) Testing for Disproportionately Affected Populations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-19

    ...: Notice. Notice of Intent to increase funding available to make awards under the Centers for Disease Control and Prevention Funding Opportunity Announcement CDC-RFA-PS10-10138, ``Expanded Human Immunodeficiency Virus (HIV) Testing for Disproportionately Affected Populations''. Additional funding from the...

  10. Responses to alternative rainfall regimes and antipoaching in a migratory system.

    PubMed

    Holdo, Ricardo M; Galvin, Kathleen A; Knapp, Eli; Polasky, Stephen; Hilborn, Ray; Holt, Robert D

    2010-03-01

    Migratory ungulates may be particularly vulnerable to the challenges imposed by growing human populations and climate change. These species depend on vast areas to sustain their migratory behavior, and in many cases come into frequent contact with human populations outside protected areas. They may also act as spatial coupling agents allowing feedbacks between ecological systems and local economies, particularly in the agropastoral subsistence economies found in the African savanna biome. We used HUMENTS, a spatially realistic socioecological model of the Greater Serengeti Ecosystem in East Africa, to explore the potential impacts of changing climate and poaching on the migratory wildebeest (Connochaetes taurinus) population, the fire regime, and habitat structure in the ecosystem, as well as changes in the size and economic activities of the human population outside the protected area. Unlike earlier models, the HUMENTS model predicted only moderate declines in the wildebeest population associated with an increasing human population over the next century, with a gradual expansion of agriculture, more poaching, and increases in fire frequency and reduced tree density. Changes in rainfall were predicted to have strong asymmetric effects on the size and economic activity of the human population and on livestock, and more moderate effects on wildlife and other ecological indicators. Conversely, antipoaching had a stronger effect on the ecological portion of the system because of its effect on wildebeest (and therefore on fire and habitat structure), and a weaker effect on the socioeconomic component, except in areas directly adjacent to the protected-area boundary, which were affected by crop-raiding and the availability of wildlife as a source of income. The results highlight the strong direct and indirect effects of rainfall on the various components of socioecological systems in semiarid environments, and the key role of mobile wildlife populations as agents of spatial coupling between the human-dominated and natural portions of ecosystems. They also underscore the fundamental importance of considering the spatial configuration of hunting refuges across the landscape in relation to human populations.

  11. Potential population growth and harmful effects on humans from bed bug populations exposed to different feeding regimes.

    PubMed

    Pereira, R M; Taylor, A S; Lehnert, M P; Koehler, P G

    2013-06-01

    Effects of host availability and feeding period on bed bugs, Cimex lectularius (L.) (Hemiptera: Cimicidae), were measured. Population growth and the potential harmful effect of bed bug populations on human hosts were modelled. Bloodmeal sizes were affected by both feeding length and frequency, with >2-fold difference between insects fed daily or weekly. Blood consumption increased >2-fold between bed bugs fed occasionally and often, and 1.5-fold between occasional and daily feeding. Bed bugs fed more often than once a week, potentially every 2-4 days. Egg production was associated with nutrition, being strongly correlated with blood consumption in the previous week. Bed bug populations can grow under different feeding regimes and are hard to control with <80% mortality. Bed bugs can survive and grow even in locations with a limited blood supply, where bed bug persistence may be important for the continual spread of populations. Persistence in non-traditional locations and a potential association with human pathogens increase the health risks of bed bugs. Potential blood loss as a result of a bed bug can have serious consequences because uncontrolled populations can reach harmful levels in 3-8 months. The reproduction potential of bed bug populations suggests serious consequences to human health and the need for efficacious control measures. © 2012 The Royal Entomological Society.

  12. A review of the relationships between human population density and biodiversity.

    PubMed

    Luck, Gary W

    2007-11-01

    To explore the impacts of increasing human numbers on nature, many studies have examined relationships between human population density (HPD) and biodiversity change. The implicit assumption in many of these studies is that as population density increases so does the threat to biodiversity. The implications of this assumption are compounded by recent research showing that species richness for many taxonomic groups is often highest in areas with high HPD. If increasing HPD is a threat to conservation, this threat may be magnified owing to the spatial congruence between people and species richness. Here, I review the relationships between HPD and measures of biodiversity status focussing in particular on evidence for the spatial congruence between people and species richness and the threat that increasing HPD may pose to biodiversity conservation. The review is split into two major sections: (i) a quantitative assessment of 85 studies covering 401 analyses, including meta-analyses on discrete relationships; and (ii) a discussion of the implications of the quantitative analyses and major issues raised in the literature. Our understanding of the relationships between HPD and biodiversity is skewed by geographic and taxonomic biases in the literature. Most research has been conducted in the Northern Hemisphere and focussed primarily on birds and mammals, largely ignoring relationships with other taxonomic groups. A total of 127 analyses compared HPD with the species richness of particular taxonomic groups. A meta-analysis of these results found a significant positive population correlation indicating that, on average, species-rich regions and human settlements co-occur. However, there was substantial unexplained heterogeneity in these data. Some of this heterogeneity was explained by the size of the sampling unit used by researchers - as this increased so did the strength of the correlation between HPD and species richness. The most convincing result for a taxonomic group was a significant positive population correlation between HPD and bird species richness. Significant positive population correlations were also found for HPD versus the richness of threatened and geographically restricted species. Hence, there is reasonably good evidence for spatial congruence between people and species-rich regions. The reasons for this congruence are only just beginning to be explored, but key mutual drivers appear to include available energy and elevation. The evidence for increasing HPD as a threat to conservation was weak, owing primarily to the extreme heterogeneity in the approaches used to address this issue. There was some suggestion of a positive relationship between HPD and species extinction, but this result should be interpreted with caution owing to the wide diversity of approaches used to measure extinction. Identifying strong links between human development and species extinction is hampered in part by the difficulty of recording extinction events. The most convincing indication of the negative impact of increasing HPD was a significant negative population correlation between density and the size of protected areas. The magnitude and implications of spatial congruence between people and biodiversity are now being explored using the principles of complementarity and irreplaceability. Human development as a threat to conservation is usually assessed within a complex, interdisciplinary modelling framework, although population size is still considered a key factor. Future population growth and expansion of human settlements will present increasing challenges for conserving species-rich regions and maximising the benefits humans gain from nature.

  13. Wolf management in the 21st century: From public input to sterilization

    USGS Publications Warehouse

    Mech, L.D.; Fritts, S.H.; Nelson, M.E.

    1996-01-01

    Human-population increase and land development portend increasing conflict with large predators. Concurrently, changes and diversification of human attitudes are bringing increased disagreement about wildlife management. Animal-rights advocacy resulting from urbanization of human populations conflicts with traditional wildlife management. These forces focus more on wolves than on other wildlife because of strong public and media interest in wolves. Thus wolf management in the future will come under even greater public scrutiny, involve more public input, and may have greater restrictions imposed on it. This will lead to increased complexity in wolf management including more zoning, more experimentation with lethal and non-lethal capture techniques and alternate methods of alleviating damage to pets, livestock, and large ungulate herds, and greater public and private subsidy of wolf damage. One form of non-lethal control of wolf populations that may hold some promise is direct sterilization of males to reduce the biotic potential of the wolf population. Experimental vasectomy of five wild male wolves from four packs in Minnesota indicates that sterile males will continue to hold mates and territories, which would be necessary if sterilization is to be a viable technique for assisting with population control. If sterile males held territories but failed to produce pups, such territories might contain only about a third the number of wolves as fertile pack territories. Because wolves are long-lived in unexploited populations and their territories are large, direct sterilization of relatively few animals each year might significantly reduce populations.

  14. Do we have to choose between feeding the human population and conserving nature? Modelling the global dependence of people on ecosystem services.

    PubMed

    Cazalis, Victor; Loreau, Michel; Henderson, Kirsten

    2018-09-01

    The ability of the human population to continue growing depends strongly on the ecosystem services provided by nature. Nature, however, is becoming more and more degraded as the number of individuals increases, which could potentially threaten the future well-being of the human population. We use a dynamic model to conceptualise links between the global proportion of natural habitats and human demography, through four categories of ecosystem services (provisioning, regulating, cultural recreational and informational) to investigate the common future of nature and humanity in terms of size and well-being. Our model shows that there is generally a trade-off between the quality of life and human population size and identifies four short-term scenarios, corresponding to three long-term steady states of the model. First, human population could experience declines if nature becomes too degraded and regulating services diminish; second the majority of the population could be in a famine state, where the population continues to grow with minimal food provision. Between these scenarios, a desirable future scenario emerges from the model. It occurs if humans convert enough land to feed all the population, while maintaining biodiversity and ecosystem services. Finally, we find a fourth scenario, which combines famine and a decline in the population because of an overexploitation of land leading to a decrease in food production. Human demography is embedded in natural dynamics; the two factors should be considered together if we are to identify a desirable future for both nature and humans. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Challenge theme 1: Understanding and preserving ecological resources: Chapter 3 in United States-Mexican Borderlands: Facing tomorrow's challenges through USGS science

    USGS Publications Warehouse

    Moring, J. Bruce; Papoulias, Diana M.; van Riper, Charles

    2013-01-01

    Texas Plains; and Western Gulf Coastal Plain. The unique geology and many of the distinctive geographic features and climatic conditions that have given rise to the diverse populations of plants and animals found in the Borderlands also attract human populations. The number of people living in the Borderlands has increased dramatically over recent years, from about 7 million in 1980 to almost 12 million in 2003; the population is estimated to be more than 18 million by 2020 (Peach and Williams, 2003). The human population increase and associated change in land use have contributed to habitat fragmentation and habitat loss for native species, thus threatening their survival. Some ways in which humans negatively affect plants and animals in the Borderlands include dewatering of aquatic ecosystems, water pollution, introduction and spread of invasive species, outdoor lighting, military and border enforcement activity, and energy development and transmission.

  16. Effects of Remedial Sport Hunting on Cougar Complaints and Livestock Depredations

    PubMed Central

    Peebles, Kaylie A.; Wielgus, Robert B.; Maletzke, Benjamin T.; Swanson, Mark E.

    2013-01-01

    Remedial sport hunting of predators is often used to reduce predator populations and associated complaints and livestock depredations. We assessed the effects of remedial sport hunting on reducing cougar complaints and livestock depredations in Washington from 2005 to 2010 (6 years). The number of complaints, livestock depredations, cougars harvested, estimated cougar populations, human population and livestock populations were calculated for all 39 counties and 136 GMUs (game management units) in Washington. The data was then analyzed using a negative binomial generalized linear model to test for the expected negative relationship between the number of complaints and depredations in the current year with the number of cougars harvested the previous year. As expected, we found that complaints and depredations were positively associated with human population, livestock population, and cougar population. However, contrary to expectations we found that complaints and depredations were most strongly associated with cougars harvested the previous year. The odds of increased complaints and livestock depredations increased dramatically (36 to 240%) with increased cougar harvest. We suggest that increased young male immigration, social disruption of cougar populations, and associated changes in space use by cougars - caused by increased hunting resulted in the increased complaints and livestock depredations. Widespread indiscriminate hunting does not appear to be an effective preventative and remedial method for reducing predator complaints and livestock depredations. PMID:24260291

  17. Predicting Metapopulation Responses to Conservation in Human-Dominated Landscapes

    Treesearch

    Zachary S. Ladin; Vincent D' Amico; Jan M. Baetens; Roland R. Roth; W. Gregory Shriver

    2016-01-01

    Loss of habitat to urbanization is a primary cause of population declines as human-dominated landscapes expand at increasing rates. Understanding how the relative effects of different conservation strategies is important to slow population declines for species in urban landscapes. We studied the wood thrush Hylocichla mustelina, a declining forest-...

  18. Natural selection and infectious disease in human populations

    PubMed Central

    Karlsson, Elinor K.; Kwiatkowski, Dominic P.; Sabeti, Pardis C.

    2015-01-01

    The ancient biological 'arms race' between microbial pathogens and humans has shaped genetic variation in modern populations, and this has important implications for the growing field of medical genomics. As humans migrated throughout the world, populations encountered distinct pathogens, and natural selection increased the prevalence of alleles that are advantageous in the new ecosystems in both host and pathogens. This ancient history now influences human infectious disease susceptibility and microbiome homeostasis, and contributes to common diseases that show geographical disparities, such as autoimmune and metabolic disorders. Using new high-throughput technologies, analytical methods and expanding public data resources, the investigation of natural selection is leading to new insights into the function and dysfunction of human biology. PMID:24776769

  19. Poaching and human encroachment reverse recovery of African savannah elephants in south-east Angola despite 14 years of peace.

    PubMed

    Schlossberg, Scott; Chase, Michael J; Griffin, Curtice R

    2018-01-01

    With populations of African savannah elephants (Loxodonta africana) declining across the continent, assessing the status of individual elephant populations is important for conservation. Angola's elephant population represents a key linkage between the larger populations of Namibia and Botswana. Elephants in Angola were decimated during the 1975-2002 Angolan civil war, but a 2005 survey showed that populations were recolonizing former habitats. Between 2005 and 2015, no research was permitted on elephants in Angola, but elsewhere in Africa many elephant populations experienced a poaching crisis. In 2015, we were able to resume elephant research in Angola. We used aerial surveys and satellite monitoring of collared elephants to determine the current status of elephant populations in Angola and to learn how human populations may be affecting elephant habitat usage. The aerial survey revealed a population of 3,395 ± SE of 797 elephants, but populations had declined 21% from the 2005 estimate. The high number of carcasses observed on the survey suggests that populations may have increased after the 2005 survey but were declining rapidly as of 2015. Satellite-collared elephants avoided areas <6 km from human indicators but preferred areas nearer humans at scales of 6-40 km, suggesting that humans may be displacing elephants from preferred habitats near rivers. Taken together, these results suggest that Angola's elephant population is experiencing intense poaching and may be losing habitat to human settlements. Without action to conserve their populations, Angola's elephants face an uncertain future.

  20. Quantifying the severity of hurricanes on extinction probabilities of a primate population: Insights into "Island" extirpations.

    PubMed

    Ameca y Juárez, Eric I; Ellis, Edward A; Rodríguez-Luna, Ernesto

    2015-07-01

    Long-term studies quantifying impacts of hurricane activity on growth and trajectory of primate populations are rare. Using a 14-year monitored population of Alouatta palliata mexicana as a study system, we developed a modeling framework to assess the relative contribution of hurricane disturbance and two types of human impacts, habitat loss, and hunting, on quasi-extinction risk. We found that the scenario with the highest level of disturbance generated a 21% increase in quasi-extinction risk by 40 years compared to scenarios of intermediate disturbance, and around 67% increase relative to that found in low disturbance scenarios. We also found that the probability of reaching quasi-extinction due to human disturbance alone was below 1% by 40 years, although such scenarios reduced population size by 70%, whereas the risk of quasi-extinction ranged between 3% and 65% for different scenarios of hurricane severity alone, in absence of human impacts. Our analysis moreover found that the quasi-extinction risk driven by hunting and hurricane disturbance was significantly lower than the quasi-extinction risk posed by human-driven habitat loss and hurricane disturbance. These models suggest that hurricane disturbance has the potential to exceed the risk posed by human impacts, and, in particular, to substantially increase the speed of the extinction vortex driven by habitat loss relative to that driven by hunting. Early mitigation of habitat loss constituted the best method for reducing quasi-extinction risk: the earlier habitat loss is halted, the less vulnerable the population becomes to hurricane disturbance. By using a well-studied population of A. p. mexicana, we help understand the demographic impacts that extreme environmental disturbance can trigger on isolated populations of taxa already endangered in other systems where long-term demographic data are not available. For those experiencing heavy anthropogenic pressure and lacking sufficiently evolved coping strategies against unpredictable environmental disturbance, the risk of population extinction can be exacerbated. © 2015 Wiley Periodicals, Inc.

  1. [A profile of the population of Indonesia: developing human resources].

    PubMed

    Mantra, I B

    1991-01-01

    Population characteristics and their implications for human resource development in Indonesia are analyzed using data from official sources, including the 1990 census. The author concludes that concurrent with some socioeconomic development have been improvements in conditions and characteristics of the population, as seen in the declines in the proportion of the dependent child population and in fertility and mortality rates. An increase in spontaneous internal migration in response to changes in local conditions is also noted. (SUMMARY IN ENG)

  2. Human and cattle population changes in deltaic West Bengal, India between 1977-1987

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Odend'hal, S.

    1988-03-01

    In 1967-1970, 3.81 km/sup 2/ of a densely populated deltaic area of Hooghly district in West Bengal, India was intensively studied. This same area was resurveyed in 1977 and 1987. From 1977-1987, the human population has increased 10.1%, while the number of households has increased 25%. The total number of children below 10 years of age has diminished. The cattle have increased 26.5%. The number of working-age male cattle has dropped significantly with reliance, primarily on hand tractor power for field cultivation. The number of female cattle has increased substantially. Artificial insemination and the use of temperate breeds of bullsmore » have had an obvious impact. Improvements in the general environment were observed.« less

  3. Frog decline, frog malformations, and a comparison of frog and human health.

    PubMed

    Cohen, M M

    2001-11-22

    The decline in frog populations and the increase in the frequency of frog malformations are discussed. Topics considered for analysis include chytridiomycosis, retinoids, UV-B radiation, chemical contaminants, environmental threats, introduced invasive species and predation, unsustainable use, and enigmatic decline. Care must be taken to distinguish between hypotheses, laboratory experiments, and the findings in feral frog populations. Clearly, the causes of population decline and malformations are heterogeneous. The subject of frogs and humans is addressed under three subheadings: the importance of frogs to human societies, medical implications of frog studies, and a comparison of frog and human disease factors. Copyright 2001 Wiley-Liss, Inc.

  4. Innovation and the growth of human population.

    PubMed

    Weinberger, V P; Quiñinao, C; Marquet, P A

    2017-12-05

    Biodiversity is sustained by and is essential to the services that ecosystems provide. Different species would use these services in different ways, or adaptive strategies, which are sustained in time by continuous innovations. Using this framework, we postulate a model for a biological species ( Homo sapiens ) in a finite world where innovations, aimed at increasing the flux of ecosystem services (a measure of habitat quality), increase with population size, and have positive effects on the generation of new innovations (positive feedback) as well as costs in terms of negatively affecting the provision of ecosystem services. We applied this model to human populations, where technological innovations are driven by cumulative cultural evolution. Our model shows that depending on the net impact of a technology on the provision of ecosystem services ( θ ), and the strength of technological feedback ( ξ ), different regimes can result. Among them, the human population can fill the entire planet while maximizing their well-being, but not exhaust ecosystem services. However, this outcome requires positive or green technologies that increase the provision of ecosystem services with few negative externalities or environmental costs, and that have a strong positive feedback in generating new technologies of the same kind. If the feedback is small, then the technological stock can collapse together with the human population. Scenarios where technological innovations generate net negative impacts may be associated with a limited technological stock as well as a limited human population at equilibrium and the potential for collapse. The only way to fill the planet with humans under this scenario of negative technologies is by reducing the technological stock to a minimum. Otherwise, the only feasible equilibrium is associated with population collapse. Our model points out that technological innovations per se may not help humans to grow and dominate the planet. Instead, different possibilities unfold for our future depending on their impact on the environment and on further innovation.This article is part of the themed issue 'Process and pattern in innovations from cells to societies'. © 2017 The Author(s).

  5. GM biofortified crops: potential effects on targeting the micronutrient intake gap in human populations.

    PubMed

    De Steur, Hans; Mehta, Saurabh; Gellynck, Xavier; Finkelstein, Julia L

    2017-04-01

    Genetic engineering has been successfully applied to increase micronutrient content in staple crops. Nutrition evidence is key to ensure scale-up and successful implementation. Unlike conventional plant breeding efforts, research on the efficacy or effectiveness of GM biofortified crops on nutritional status in human populations is lacking. This review reports on the potential role of GM biofortified crops in closing the micronutrient gap - increasing the dietary intake of micronutrients in human populations. To date, one clinical trial in the United States reported a high bio-conversion rate of β-carotene in Golden Rice, and potential effects of GM biofortified crop consumption on dietary intake and nutritional outcomes are promising. However, further research needs to confirm the ex ante assessments in target regions. Copyright © 2017. Published by Elsevier Ltd.

  6. Human-caused mortality influences spatial population dynamics: pumas in landscapes with varying mortality risks

    USGS Publications Warehouse

    Newby, Jesse R.; Mills, L. Scott; Ruth, Toni K.; Pletscher, Daniel H.; Mitchell, Michael S.; Quigley, Howard B.; Murphy, Kerry M.; DeSimone, Rich

    2013-01-01

    An understanding of how stressors affect dispersal attributes and the contribution of local populations to multi-population dynamics are of immediate value to basic and applied ecology. Puma (Puma concolor) populations are expected to be influenced by inter-population movements and susceptible to human-induced source–sink dynamics. Using long-term datasets we quantified the contribution of two puma populations to operationally define them as sources or sinks. The puma population in the Northern Greater Yellowstone Ecosystem (NGYE) was largely insulated from human-induced mortality by Yellowstone National Park. Pumas in the western Montana Garnet Mountain system were exposed to greater human-induced mortality, which changed over the study due to the closure of a 915 km2 area to hunting. The NGYE’s population growth depended on inter-population movements, as did its ability to act as a source to the larger region. The heavily hunted Garnet area was a sink with a declining population until the hunting closure, after which it became a source with positive intrinsic growth and a 16× increase in emigration. We also examined the spatial and temporal characteristics of individual dispersal attributes (emigration, dispersal distance, establishment success) of subadult pumas (N = 126). Human-caused mortality was found to negatively impact all three dispersal components. Our results demonstrate the influence of human-induced mortality on not only within population vital rates, but also inter-population vital rates, affecting the magnitude and mechanisms of local population’s contribution to the larger metapopulation.

  7. Density-Dependent Prevalence of Francisella tularensis in Fluctuating Vole Populations, Northwestern Spain

    PubMed Central

    Rodríguez-Pastor, Ruth; Escudero, Raquel; Vidal, Dolors; Mougeot, François; Arroyo, Beatriz; Lambin, Xavier; Vila-Coro, Ave Maria; Rodríguez-Moreno, Isabel; Anda, Pedro

    2017-01-01

    Tularemia in humans in northwestern Spain is associated with increases in vole populations. Prevalence of infection with Francisella tularensis in common voles increased to 33% during a vole population fluctuation. This finding confirms that voles are spillover agents for zoonotic outbreaks. Ecologic interactions associated with tularemia prevention should be considered. PMID:28726608

  8. The natural history of violence.

    PubMed Central

    Russell, C; Russell, W M

    1979-01-01

    In the past, human violence was associated with food shortage, but recently it has increased even in relatively well-fed societies. The reason appears from studies of monkeys under relaxed, spacious conditions and under crowding stress. Uncrowded monkeys have unaggressive leaders, rarely quarrel, and protect females and young. Crowded monkeys (even well-fed) have brutal bosses, often quarrel, and wound and kill each other, including females and young. Crowding has similar behaviour effects on other mammals, with physiological disturbances including greater susceptibility to infections. All this appears to be a regular response to overpopulation, reducing the population before it has depleted its natural resources. Human beings, like monkeys and other mammals, need ample space, and become more violent when crowded. Human history is marked by population cycles: population outgrows resources, the resulting violence, stress and disease mortality cuts down the population, leading to a relief period of social and cultural progress, till renewed population growth produces the next crisis. The modern population crisis is world-wide, and explains the increase of violence even in well-fed societies. The solution to the problem of violence is to substitute voluntary birth control for involuntary death control, and bring about relaxed conditions for a reduced world population. PMID:114662

  9. Learning about human population history from ancient and modern genomes.

    PubMed

    Stoneking, Mark; Krause, Johannes

    2011-08-18

    Genome-wide data, both from SNP arrays and from complete genome sequencing, are becoming increasingly abundant and are now even available from extinct hominins. These data are providing new insights into population history; in particular, when combined with model-based analytical approaches, genome-wide data allow direct testing of hypotheses about population history. For example, genome-wide data from both contemporary populations and extinct hominins strongly support a single dispersal of modern humans from Africa, followed by two archaic admixture events: one with Neanderthals somewhere outside Africa and a second with Denisovans that (so far) has only been detected in New Guinea. These new developments promise to reveal new stories about human population history, without having to resort to storytelling.

  10. Can an increase in leaf iron reductase activity enhance seed iron accumulation in soybean?

    USDA-ARS?s Scientific Manuscript database

    Iron is an important micronutrient for human nutrition, with plant foods providing a significant amount of dietary iron in certain population groups, and in some cases, providing the sole source of dietary iron. Because iron deficiency is unfortunately common in many human populations, we have been...

  11. Wolf population dynamics in the U.S. Northern Rocky Mountains are affected by recruitment and human-caused mortality

    USGS Publications Warehouse

    Gude, J.A.; Mitchell, M.S.; Russell, R.E.; Sime, C.A.; Bangs, E.E.; Mech, L.D.; Ream, R.R.

    2012-01-01

    Reliable analyses can help wildlife managers make good decisions, which are particularly critical for controversial decisions such as wolf (Canis lupus) harvest. Creel and Rotella (2010) recently predicted substantial population declines in Montana wolf populations due to harvest, in contrast to predictions made by Montana Fish, Wildlife and Parks (MFWP). We replicated their analyses considering only those years in which field monitoring was consistent, and we considered the effect of annual variation in recruitment on wolf population growth. Rather than assuming constant rates, we used model selection methods to evaluate and incorporate models of factors driving recruitment and human-caused mortality rates in wolf populations in the Northern Rocky Mountains. Using data from 27 area-years of intensive wolf monitoring, we show that variation in both recruitment and human-caused mortality affect annual wolf population growth rates and that human-caused mortality rates have increased with the sizes of wolf populations. We document that recruitment rates have decreased over time, and we speculate that rates have decreased with increasing population sizes and/or that the ability of current field resources to document recruitment rates has recently become less successful as the number of wolves in the region has increased. Estimates of positive wolf population growth in Montana from our top models are consistent with field observations and estimates previously made by MFWP for 2008-2010, whereas the predictions for declining wolf populations of Creel and Rotella (2010) are not. Familiarity with limitations of raw data, obtained first-hand or through consultation with scientists who collected the data, helps generate more reliable inferences and conclusions in analyses of publicly available datasets. Additionally, development of efficient monitoring methods for wolves is a pressing need, so that analyses such as ours will be possible in future years when fewer resources will be available for monitoring. ?? 2011 The Wildlife Society. Copyright ?? The Wildlife Society, 2011.

  12. Emerging landscape degradation trends in the East African Horn

    NASA Astrophysics Data System (ADS)

    Pricope, N. G.; Michaelsen, J.; Husak, G. J.; Funk, C. C.; Lopez-Carr, D.

    2012-12-01

    Increasing climate variability along with declining trends in rainfall represent major risk factors affecting food security in many regions of the world. We identify Africa-wide regions where significant rainfall decreases from 1979-2011 are coupled with significant human population density increases. The rangelands of the East African Horn remain one of the world's most food insecure regions with significantly increasing human populations predominantly dependent on pastoralist and agro-pastoralist livelihoods. Widespread vegetation degradation is occurring, adversely impacting fragile ecosystems and human livelihoods. Using MODIS land cover and normalized difference vegetation index (NDVI) data collected since 2000, we observe significant changes in vegetation patterns and productivity over the last decade across the East African Horn and demonstrate that these two products can be used concurrently at large spatial scales to monitor vegetation dynamics at decadal time scales. Results demonstrate that a near doubling of the population in pastoral regions is linked with hotspots of degradation in vegetation condition. The most significant land cover change and browning trends are observed in areas experiencing drying precipitation trends in addition to increasing population pressures. These findings have serious implications for current and future regional food security monitoring and forecasting and for mitigation and adaptation strategies in a region where population is expected to continue increasing against a backdrop of drying climate trends.Fig.1(a)Change in standardized precipitation index in Africa between 1979-2010 (b)Change in population density at continental scale using the GRUMPv1 1990 and 2000 and AfriPop 2010 population density datasets Fig.2 Land cover change trajectories based on 2001-2009 MOD12Q1 Land Cover product for the East African Horn overlaid over aggregated FEWS Net Livelihoods Zones.

  13. Indirect effects of human-induced environmental change on offspring production mediated by behavioural responses.

    PubMed

    Candolin, Ulrika; Nieminen, Anne; Nyman, Johanna

    2014-01-01

    Human-induced rapid environmental changes often cause behavioural alterations in animals. The consequences that these alterations in turn have for the viability of populations are, however, poorly known. We used a population of threespine sticklebacks Gasterosteus aculeatus in the Baltic Sea to investigate the consequences of behavioural responses to human-induced eutrophication for offspring production. The investigated population has been growing during the last decades, and one cause could be increased offspring production. We combined field-based surveys with laboratory-based experiments, and found that an enhanced growth of macroalgae relaxed agonistic interactions among males. This allowed more males to nest, improved hatching success, and increased the number of reproductive cycles that males completed. Thus, the behavioural responses were adaptive at the individual level and increased offspring production. However, a larger proportion of small males of low competitive ability reproduced in dense vegetation. As male size and dominance are heritable, this could influence the genetic composition of the offspring. Together with a higher number of offspring produced, this could influence natural selection and the rate of adaptation to the changing environment. Thus, behavioural responses to a rapid human-induced environmental change can influence offspring production, with potential consequences for population dynamics and evolutionary processes.

  14. Poaching and human encroachment reverse recovery of African savannah elephants in south-east Angola despite 14 years of peace

    PubMed Central

    Chase, Michael J.; Griffin, Curtice R.

    2018-01-01

    With populations of African savannah elephants (Loxodonta africana) declining across the continent, assessing the status of individual elephant populations is important for conservation. Angola’s elephant population represents a key linkage between the larger populations of Namibia and Botswana. Elephants in Angola were decimated during the 1975–2002 Angolan civil war, but a 2005 survey showed that populations were recolonizing former habitats. Between 2005 and 2015, no research was permitted on elephants in Angola, but elsewhere in Africa many elephant populations experienced a poaching crisis. In 2015, we were able to resume elephant research in Angola. We used aerial surveys and satellite monitoring of collared elephants to determine the current status of elephant populations in Angola and to learn how human populations may be affecting elephant habitat usage. The aerial survey revealed a population of 3,395 ± SE of 797 elephants, but populations had declined 21% from the 2005 estimate. The high number of carcasses observed on the survey suggests that populations may have increased after the 2005 survey but were declining rapidly as of 2015. Satellite-collared elephants avoided areas <6 km from human indicators but preferred areas nearer humans at scales of 6–40 km, suggesting that humans may be displacing elephants from preferred habitats near rivers. Taken together, these results suggest that Angola’s elephant population is experiencing intense poaching and may be losing habitat to human settlements. Without action to conserve their populations, Angola’s elephants face an uncertain future. PMID:29538387

  15. Coalescent genealogy samplers: windows into population history

    PubMed Central

    Kuhner, Mary K.

    2016-01-01

    Coalescent genealogy samplers attempt to estimate past qualities of a population, such as its size, growth rate, patterns of gene flow or time of divergence from another population, based on samples of molecular data. Genealogy samplers are increasingly popular because of their potential to disentangle complex population histories. In the last decade they have been widely applied to systems ranging from humans to viruses. Findings include detection of unexpected reproductive inequality in fish, new estimates of historical whale abundance, exoneration of humans for the prehistoric decline of bison and inference of a selective sweep on the human Y chromosome. This review summarizes available genealogy-sampler software, including data requirements and limitations on the use of each program. PMID:19101058

  16. Coalescent genealogy samplers: windows into population history.

    PubMed

    Kuhner, Mary K

    2009-02-01

    Coalescent genealogy samplers attempt to estimate past qualities of a population, such as its size, growth rate, patterns of gene flow or time of divergence from another population, based on samples of molecular data. Genealogy samplers are increasingly popular because of their potential to disentangle complex population histories. In the last decade they have been widely applied to systems ranging from humans to viruses. Findings include detection of unexpected reproductive inequality in fish, new estimates of historical whale abundance, exoneration of humans for the prehistoric decline of bison and inference of a selective sweep on the human Y chromosome. This review summarizes available genealogy-sampler software, including data requirements and limitations on the use of each program.

  17. Human impacts on large benthic foraminifers near a densely populated area of Majuro Atoll, Marshall Islands.

    PubMed

    Osawa, Yoko; Fujita, Kazuhiko; Umezawa, Yu; Kayanne, Hajime; Ide, Yoichi; Nagaoka, Tatsutoshi; Miyajima, Toshihiro; Yamano, Hiroya

    2010-08-01

    Human impacts on sand-producing, large benthic foraminifers were investigated on ocean reef flats at the northeast Majuro Atoll, Marshall Islands, along a human population gradient. The densities of dominant foraminifers Calcarina and Amphistegina declined with distance from densely populated islands. Macrophyte composition on ocean reef flats differed between locations near sparsely or densely populated islands. Nutrient concentrations in reef-flat seawater and groundwater were high near or on densely populated islands. delta(15)N values in macroalgal tissues indicated that macroalgae in nearshore lagoons assimilate wastewater-derived nitrogen, whereas those on nearshore ocean reef flats assimilate nitrogen from other sources. These results suggest that increases in the human population result in high nutrient loading in groundwater and possibly into nearshore waters. High nutrient inputs into ambient seawater may have both direct and indirect negative effects on sand-producing foraminifers through habitat changes and/or the collapse of algal symbiosis. Copyright 2010 Elsevier Ltd. All rights reserved.

  18. Post-invasion demography of prehistoric humans in South America.

    PubMed

    Goldberg, Amy; Mychajliw, Alexis M; Hadly, Elizabeth A

    2016-04-14

    As the last habitable continent colonized by humans, the site of multiple domestication hotspots, and the location of the largest Pleistocene megafaunal extinction, South America is central to human prehistory. Yet remarkably little is known about human population dynamics during colonization, subsequent expansions, and domestication. Here we reconstruct the spatiotemporal patterns of human population growth in South America using a newly aggregated database of 1,147 archaeological sites and 5,464 calibrated radiocarbon dates spanning fourteen thousand to two thousand years ago (ka). We demonstrate that, rather than a steady exponential expansion, the demographic history of South Americans is characterized by two distinct phases. First, humans spread rapidly throughout the continent, but remained at low population sizes for 8,000 years, including a 4,000-year period of 'boom-and-bust' oscillations with no net growth. Supplementation of hunting with domesticated crops and animals had a minimal impact on population carrying capacity. Only with widespread sedentism, beginning ~5 ka, did a second demographic phase begin, with evidence for exponential population growth in cultural hotspots, characteristic of the Neolithic transition worldwide. The unique extent of humanity's ability to modify its environment to markedly increase carrying capacity in South America is therefore an unexpectedly recent phenomenon.

  19. Population density-dependent hair cortisol concentrations in rhesus monkeys (Macaca mulatta)

    PubMed Central

    Dettmer, A.M.; Novak, M.A.; Meyer, J.S.; Suomi, S.J.

    2014-01-01

    Summary Population density is known to influence acute measures of hypothalamic-pituitary-adrenal (HPA) axis activity in a variety of species, including fish, deer, birds, and humans. However, the effects of population density on levels of chronic stress are unknown. Given the fact that exposure to chronically elevated levels of circulating glucocorticoids results in a host of health disparities in animals and humans alike, it is important to understand how population density may impact chronic stress. We assessed hair cortisol concentrations (HCCs), which are reliable indicators of chronic HPA axis activity, in rhesus monkeys (Macaca mulatta) to determine the influence of population density on these values. In Experiment 1, we compared HCCs of monkeys living in high-density (HD; 1 monkey/0.87m2) and low-density (LD; 1 monkey/63.37m2) environments (N=236 hair samples) and found that HD monkeys exhibited higher hair cortisol across all age categories (infant, juvenile, young adult, adult, and aged) except infancy and aged (F(5)=4.240, p=0.001), for which differences were nearly significant. HD monkeys also received more severe fight wounds than LD monkeys (χ2=26.053, p<0.001), though no effects of dominance status emerged. In Experiment 2, we examined how HCCs change with fluctuating population levels across five years in the adult LD monkeys (N=155 hair samples) and found that increased population density was significantly positively correlated with HCCs in this semi-naturalistic population (r(s)=0.975, p=0.005). These are the first findings to demonstrate that increased population density is associated with increased chronic, endogenous glucocorticoid exposure in a nonhuman primate species. We discuss the implications of these findings with respect to laboratory research, population ecology, and human epidemiology. PMID:24636502

  20. Population density-dependent hair cortisol concentrations in rhesus monkeys (Macaca mulatta).

    PubMed

    Dettmer, A M; Novak, M A; Meyer, J S; Suomi, S J

    2014-04-01

    Population density is known to influence acute measures of hypothalamic-pituitary-adrenal (HPA) axis activity in a variety of species, including fish, deer, birds, and humans. However, the effects of population density on levels of chronic stress are unknown. Given the fact that exposure to chronically elevated levels of circulating glucocorticoids results in a host of health disparities in animals and humans alike, it is important to understand how population density may impact chronic stress. We assessed hair cortisol concentrations (HCCs), which are reliable indicators of chronic HPA axis activity, in rhesus monkeys (Macaca mulatta) to determine the influence of population density on these values. In Experiment 1, we compared HCCs of monkeys living in high-density (HD; 1 monkey/0.87m(2)) and low-density (LD; 1 monkey/63.37m(2)) environments (N=236 hair samples) and found that HD monkeys exhibited higher hair cortisol across all age categories (infant, juvenile, young adult, adult, and aged) except infancy and aged (F(5)=4.240, p=0.001), for which differences were nearly significant. HD monkeys also received more severe fight wounds than LD monkeys (χ(2)=26.053, p<0.001), though no effects of dominance status emerged. In Experiment 2, we examined how HCCs change with fluctuating population levels across 5 years in the adult LD monkeys (N=155 hair samples) and found that increased population density was significantly positively correlated with HCCs in this semi-naturalistic population (r(s)=0.975, p=0.005). These are the first findings to demonstrate that increased population density is associated with increased chronic, endogenous glucocorticoid exposure in a nonhuman primate species. We discuss the implications of these findings with respect to laboratory research, population ecology, and human epidemiology. Published by Elsevier Ltd.

  1. Genome-wide association studies in Africans and African Americans: Expanding the Framework of the Genomics of Human Traits and Disease

    PubMed Central

    Peprah, Emmanuel; Xu, Huichun; Tekola-Ayele, Fasil; Royal, Charmaine D.

    2014-01-01

    Genomic research is one of the tools for elucidating the pathogenesis of diseases of global health relevance, and paving the research dimension to clinical and public health translation. Recent advances in genomic research and technologies have increased our understanding of human diseases, genes associated with these disorders, and the relevant mechanisms. Genome-wide association studies (GWAS) have proliferated since the first studies were published several years ago, and have become an important tool in helping researchers comprehend human variation and the role genetic variants play in disease. However, the need to expand the diversity of populations in GWAS has become increasingly apparent as new knowledge is gained about genetic variation. Inclusion of diverse populations in genomic studies is critical to a more complete understanding of human variation and elucidation of the underpinnings of complex diseases. In this review, we summarize the available data on GWAS in recent-African ancestry populations within the western hemisphere (i.e. African Americans and peoples of the Caribbean) and continental African populations. Furthermore, we highlight ways in which genomic studies in populations of recent African ancestry have led to advances in the areas of malaria, HIV, prostate cancer, and other diseases. Finally, we discuss the advantages of conducting GWAS in recent African ancestry populations in the context of addressing existing and emerging global health conditions. PMID:25427668

  2. The abundance of antibiotic resistance genes in human guts has correlation to the consumption of antibiotics in animal

    PubMed Central

    Hu, Yongfei; Yang, Xi; Lu, Na; Zhu, Baoli

    2014-01-01

    Increasing evidence has accumulated to support that the human gut is a reservoir for antibiotic resistance genes. We previously identified more than 1000 genes displaying high similarity with known antibiotic resistance genes in the human gut gene set generated from the Chinese, Danish, and Spanish populations. Here, first, we add our new understanding of antibiotic resistance genes in the US and the Japanese populations; next, we describe the structure of a vancomycin-resistant operon in a Danish sample; and finally, we provide discussions on the correlation of the abundance of resistance genes in human gut with the antibiotic consumption in human medicine and in animal husbandry. These results, combined with those we published previously, provide comprehensive insights into the antibiotic resistance genes in the human gut microbiota at a population level. PMID:24637798

  3. The abundance of antibiotic resistance genes in human guts has correlation to the consumption of antibiotics in animal.

    PubMed

    Hu, Yongfei; Yang, Xi; Lu, Na; Zhu, Baoli

    2014-01-01

    Increasing evidence has accumulated to support that the human gut is a reservoir for antibiotic resistance genes. We previously identified more than 1000 genes displaying high similarity with known antibiotic resistance genes in the human gut gene set generated from the Chinese, Danish, and Spanish populations. Here, first, we add our new understanding of antibiotic resistance genes in the US and the Japanese populations; next, we describe the structure of a vancomycin-resistant operon in a Danish sample; and finally, we provide discussions on the correlation of the abundance of resistance genes in human gut with the antibiotic consumption in human medicine and in animal husbandry. These results, combined with those we published previously, provide comprehensive insights into the antibiotic resistance genes in the human gut microbiota at a population level.

  4. Human suffering.

    PubMed

    1992-12-01

    10 measures of quality of life are used to rank 141 countries in the International Human Suffering Index (HSI). The Index differentiates between extreme, high, moderate, and minimal levels of human suffering. Social welfare is the sum of 10 measures: life expectancy, daily caloric intake, clean drinking water, infant immunization, secondary school enrollment, gross national product per capita, the rate of inflation, communication technology (i.e., telephones), political freedom, and civil rights. Each measure is ranked between 0 and 10. The highest score indicates the greatest country stress, with the worst possible score being 100. About 1 billion people live in desperate poverty. Living conditions are the worst in Mozambique (93), followed by Somalia, Afghanistan, Haiti, and Sudan. Most of these countries also have high population growth. The most comfortable countries are Denmark (1), the Netherlands, Belgium, Switzerland, and Canada, which have low population growth. Total scores of 75 or greater (extreme human suffering) occur in 27 countries (20 in Africa, 16 in Asia, and Haiti) with 8% of the world's population (432 million people). High human suffering scores range between 50 and 74 and include 56 countries (24 in Africa, 16 in Asia, 15 in the Western Hemisphere, and 1 in Oceania) with 3.5 billion people. The number of countries in this grouping increased from 44 countries with 58% of world population in 1987. Moderate suffering scores range from 25-49. Countries with moderate suffering number 34 countries (9 in Europe, 13 in Asia, 8 in the Western Hemisphere, and 2 in Oceania and 2 in Africa) with 11.8% of world population (636 million). Over the preceding 5-year period the number of countries increased from 29 countries with 10% of world population. Minimal human suffering occurs in 24 countries (17 in Europe, Israel and Japan in Asia; Canada, the US, and Barbados in the Western Hemisphere; and Australia and New Zealand in Oceania) with 14.8% of world population (797 million). Five years ago 27 countries with 21% of world population were in the minimal suffering group.

  5. World Population Crisis.

    ERIC Educational Resources Information Center

    Ehrlich, Paul R.; Ehrlich, Anne H.

    1986-01-01

    Rapid population growth, rising competition for resources, and increasing environmental deterioration are intertwined factors in the human predicament that feed political tensions and conflicts of the late twentieth century. Outlines dimensions of this predicament (including data on population, growth, military spending, quality of life, and…

  6. Proactive responses to human impacts that balance development and Atlantic salmon (Salmo salar) conservation: An integrative model

    USGS Publications Warehouse

    Wilzbach, M.A.; Mather, M. E.; Folt, C.L.; Moore, A.; Naiman, R.J.; Youngson, A.F.; McMenemy, J.

    1998-01-01

    Incorporating human impacts into conservation plans is critical to protect natural resources. Using a model that examines how anthropogenic changes might be proactively influenced to promote conservation, we argue that a denser human population does not spell inevitable doom for Atlantic salmon (Salmo salar). Humans affect the Atlantic salmon ecosystem deleteriously through landscape alteration, exploitation, external inputs, and resource competition. An intact ecosystem provides positive feedback to society by providing food, ecosystem services, and improving the quality of life. As Atlantic salmon and associated ecosystem benefits are increasingly valued by society, policies, laws, and regulations that protect salmon populations and habitats are codified into a 'control system' or institutional infrastructure. Via research that helps maintain wild salmon populations and in informing the public about the benefits of a healthy Atlantic salmon ecosystem, scientists can influence public attitudes and facilitate the implementation of environmental policies that moderate harmful anthropogenic changes. Because exchange among scientists is of paramount importance in increasing our understanding of important interrelationships between humans and fish, we recommend the establishment of an international salmon organizational for research.

  7. Effects of reduced-impact logging and forest physiognomy on bat populations of lowland Amazonian forest.

    Treesearch

    Steven J. Presley; Michael R. Willig; Wunderle Jr. Joseph M.; Luis Nélio Saldanha

    2008-01-01

    1.As human population size increases, demand for natural resources will increase. Logging pressure related to increasing demands continues to threaten remote areas of Amazonian forest. A harvest protocol is required to provide renewable timber resources that meet consumer needs while minimizing negative effects on biodiversity and ecosystem services. Reduced-impact...

  8. Human drivers of ecological and evolutionary dynamics in emerging and disappearing infectious disease systems.

    PubMed

    Rogalski, Mary A; Gowler, Camden D; Shaw, Clara L; Hufbauer, Ruth A; Duffy, Meghan A

    2017-01-19

    Humans have contributed to the increased frequency and severity of emerging infectious diseases, which pose a significant threat to wild and domestic species, as well as human health. This review examines major pathways by which humans influence parasitism by altering (co)evolutionary interactions between hosts and parasites on ecological timescales. There is still much to learn about these interactions, but a few well-studied cases show that humans influence disease emergence every step of the way. Human actions significantly increase dispersal of host, parasite and vector species, enabling greater frequency of infection in naive host populations and host switches. Very dense host populations resulting from urbanization and agriculture can drive the evolution of more virulent parasites and, in some cases, more resistant host populations. Human activities that reduce host genetic diversity or impose abiotic stress can impair the ability of hosts to adapt to disease threats. Further, evolutionary responses of hosts and parasites can thwart disease management and biocontrol efforts. Finally, in rare cases, humans influence evolution by eradicating an infectious disease. If we hope to fully understand the factors driving disease emergence and potentially control these epidemics we must consider the widespread influence of humans on host and parasite evolutionary trajectories.This article is part of the themed issue 'Human influences on evolution, and the ecological and societal consequences'. © 2016 The Author(s).

  9. Economic growth and marine biodiversity: influence of human social structure on decline of marine trophic levels.

    PubMed

    Clausen, Rebecca; York, Richard

    2008-04-01

    We assessed the effects of economic growth, urbanization, and human population size on marine biodiversity. We used the mean trophic level (MTL) of marine catch as an indicator of marine biodiversity and conducted cross-national time-series analyses (1960-2003) of 102 nations to investigate human social influences on fish catch and trends in MTL. We constructed path models to examine direct and indirect effects relating to marine catch and MTL. Nations' MTLs declined with increased economic growth, increased urbanization, and increased population size, in part because of associated increased catch. These findings contradict the environmental Kuznets curve hypothesis, which claims that economic modernization will reduce human impact on the environment. To make informed decisions on issues of marine resource management, policy makers, nonprofit entities, and professional societies must recognize the need to include social analyses in overall conservation-research strategies. The challenge is to utilize the socioeconomic and ecological research in the service of a comprehensive marine-conservation movement.

  10. Effects of economics and demographics on global fisheries sustainability.

    PubMed

    Ding, Qi; Wang, Yali; Chen, Xinjun; Chen, Yong

    2017-08-01

    A good understanding of social factors that lead to marine ecological change is important to developing sustainable global fisheries. We used balanced panel models and conducted cross-national time-series analyses (1970-2010) of 122 nations to examine how economic prosperity and population growth affected the sustainability of marine ecosystems. We used catches in economic exclusive zone (EEZ); mean trophic level of fishery landings (MTL); primary production required to sustain catches (expressed as percentage of local primary production [%PPR]); and an index of ecosystem overfishing (i.e., the loss in secondary production index [L index]) as indicators of ecological change in marine ecosystems. The EEZ catch, %PPR, and L index declined gradually after gross domestic product (GDP) per capita reached $15,000, $14,000, and $19,000, respectively, and MTL increased steadily once GDP per capita exceeded $20,000. These relationships suggest that economic growth and biodiversity conservation are compatible goals. However, increasing human populations would degrade marine ecosystems. Specifically, a doubling of human population caused an increase in the %PPR of 17.1% and in the L index of 0.0254 and a decline in the MTL of 0.176. A 1% increase in human population resulted in a 0.744% increase in EEZ catch. These results highlight the importance of considering social and economic factors in developing sustainable fisheries management policy. © 2016 Society for Conservation Biology.

  11. Alpha power indexes task-related networks on large and small scales: A multimodal ECoG study in humans and a non-human primate.

    PubMed

    de Pesters, A; Coon, W G; Brunner, P; Gunduz, A; Ritaccio, A L; Brunet, N M; de Weerd, P; Roberts, M J; Oostenveld, R; Fries, P; Schalk, G

    2016-07-01

    Performing different tasks, such as generating motor movements or processing sensory input, requires the recruitment of specific networks of neuronal populations. Previous studies suggested that power variations in the alpha band (8-12Hz) may implement such recruitment of task-specific populations by increasing cortical excitability in task-related areas while inhibiting population-level cortical activity in task-unrelated areas (Klimesch et al., 2007; Jensen and Mazaheri, 2010). However, the precise temporal and spatial relationships between the modulatory function implemented by alpha oscillations and population-level cortical activity remained undefined. Furthermore, while several studies suggested that alpha power indexes task-related populations across large and spatially separated cortical areas, it was largely unclear whether alpha power also differentially indexes smaller networks of task-related neuronal populations. Here we addressed these questions by investigating the temporal and spatial relationships of electrocorticographic (ECoG) power modulations in the alpha band and in the broadband gamma range (70-170Hz, indexing population-level activity) during auditory and motor tasks in five human subjects and one macaque monkey. In line with previous research, our results confirm that broadband gamma power accurately tracks task-related behavior and that alpha power decreases in task-related areas. More importantly, they demonstrate that alpha power suppression lags population-level activity in auditory areas during the auditory task, but precedes it in motor areas during the motor task. This suppression of alpha power in task-related areas was accompanied by an increase in areas not related to the task. In addition, we show for the first time that these differential modulations of alpha power could be observed not only across widely distributed systems (e.g., motor vs. auditory system), but also within the auditory system. Specifically, alpha power was suppressed in the locations within the auditory system that most robustly responded to particular sound stimuli. Altogether, our results provide experimental evidence for a mechanism that preferentially recruits task-related neuronal populations by increasing cortical excitability in task-related cortical areas and decreasing cortical excitability in task-unrelated areas. This mechanism is implemented by variations in alpha power and is common to humans and the non-human primate under study. These results contribute to an increasingly refined understanding of the mechanisms underlying the selection of the specific neuronal populations required for task execution. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Population Problems, Teacher's Guide. Environmental Education Unit, Twelfth Grade Sociology.

    ERIC Educational Resources Information Center

    Little Rock School District, AR.

    Human population growth and the implications of increasing population on the well-being of men and nations is examined in this twelfth grade curriculum guide which is part of a series for grades 4 through 12. The primary functions of the unit are to introduce the student to reasons for population growth, results of overextended populations, and…

  13. Domestication and human demographic history in South America.

    PubMed

    Perez, S Ivan; Postillone, María Bárbara; Rindel, Diego

    2017-05-01

    The early groups of hunter-gatherers who peopled South America faced significant ecological changes in their trophic niche for a relatively short period after the initial peopling. In particular, the incorporation of cultigens during the Holocene led to a wider trophic niche and probably to an increased carrying capacity of the environment. Here, we study the relationship between the incorporation of domestic resources during the Holocene and the demographic dynamics of human populations at a regional scale in South America. We employ mitochondrial DNA (mtDNA), radiocarbon data and Bayesian methods to estimate differences in population size, human occupation and explore the demographic changes of human populations in three regions (i.e., South-Central Andes, Northwest, and South Patagonia). We also use archaeological evidence to infer the main diet changes in these regions. The absolute population size during the later Late Holocene was fifteen times larger in the South-Central Andes than in Northwest Patagonia, and two times larger in the latter region than in South Patagonia. The South-Central Andes display the earlier and more abrupt population growth, beginning about 9000 years BP, whereas Northwest Patagonia exhibits a more slow growth, beginning about 7000-7500 years BP. South Patagonia represents a later and slower population increase. In this work we uncovered a well-supported pattern of the demographic change in the populations from South-Central Andes and Patagonia, obtained on the basis of different data and quantitative approaches, which suggests that the incorporation of domestic resources was paramount for the demographic expansion of these populations during the Holocene. © 2017 Wiley Periodicals, Inc.

  14. The Climate-Population Nexus in the East African Horn: Emerging Degradation Trends in Rangeland and Pastoral Livelihood Zones

    NASA Astrophysics Data System (ADS)

    Pricope, N. G.; Husak, G. J.; Funk, C. C.; Lopez-Carr, D.

    2014-12-01

    Increasing climate variability and extreme weather conditions along with declining trends in both rainfall and temperature represent major risk factors affecting agricultural production and food security in many regions of the world. We identify regions where significant rainfall decrease from 1979-2011 over the entire continent of Africa couples with significant human population density increase. The rangelands of Ethiopia, Kenya, and Somalia in the East African Horn remain one of the world's most food insecure regions, yet have significantly increasing human populations predominantly dependent on pastoralist and agro-pastoralist livelihoods. Vegetation in this region is characterized by a variable mosaic of land covers, generally dominated by grasslands necessary for agro-pastoralism, interspersed by woody vegetation. Recent assessments indicate that widespread degradation is occurring, adversely impacting fragile ecosystems and human livelihoods. Using two underutilized MODIS products, we observe significant changes in vegetation patterns and productivity over the last decade all across the East African Horn. We observe significant vegetation browning trends in areas experiencing drying precipitation trends in addition to increasing population pressures. We also found that the drying precipitation trends only partially statistically explain the vegetation browning trends, further indicating that other factors such as population pressures and land use changes are responsible for the observed declining vegetation health. Furthermore, we show that the general vegetation browning trends persist even during years with normal rainfall conditions such as 2012, indicating potential long-term degradation of rangelands on which approximately 10 million people depend. These findings have serious implications for current and future regional food security monitoring and forecasting as well as for mitigation and adaptation strategies in a region where population is expected to continue increasing against a backdrop of drying climate trends.

  15. Review of factors affecting the distribution and abundance of waterfowl in shallow-water habitats of Chesapeake Bay

    USGS Publications Warehouse

    Perry, M.C.; Deller, A.S.

    1996-01-01

    Long-term trends of waterfowl populations in Chesapeake Bay demonstrate the importance of shallow-water habitats for waterfowl species. Although recent increases in field feeding by geese and swans lessened the importance of shallow-water areas for these species, most duck species depend almost exclusively on shallow-water habitats. Many factors influenced the distribution and abundance of waterfowl in shallow-water habitats. Habitat degradation resulted in the decline in numbers of most duck species and a change in distribution of some species. Increased numbers of mallards (Anas platyrhynchos) in recent decades probably resulted from release programs conducted by the Maryland Department of Natural Resources and private individuals. Studies of food habits since 1885 showed a decline in submerged-aquatic vegetation in the diet of some species, such as the canvasback (Aythya valisineria ), and an increase in the proportions of invertebrates in the diet. Diversity of food organisms for many waterfowl species has declined. Surveys of vegetation and invertebrates in the Chesapeake Bay generally reflect a degradation of shallow-water habitat. Human population increases in the Chesapeake Bay watershed directly and indirectly affected waterfowl distribution and abundance. The increase of exotic plant and invertebrate species in the bay, in most cases, benefited waterfowl populations. Increased contaminants have reduced the quality and quantity of habitat, although serious attempts to reverse this trend are underway. The use of shallow-water habitats by humans for fishing, hunting, boating, and other recreational and commercial uses reduced the use of shallow-water habitats by waterfowl. Humans can lessen the adverse influences on the valuable shallow-water habitats by restricting human population growth near these habitats and improving the water quality of the bay tributaries. Other affirmative actions that will improve these areas for waterfowl include greater restrictions on boat traffic in shallow-water habitats and establishing more sanctuaries in shallow-water areas that have complete protection from human disturbance.

  16. Human impacts on regional avian diversity and abundance

    Treesearch

    Christopher A. Lepczyk; Curtis H. Flather; Volker C. Radeloff; Anna M. Pidgeon; Roger B. Hammer; Jianguo Liu

    2008-01-01

    Patterns of association between humans and biodiversity typically show positive, negative, or negative quadratic relationships and can be described by 3 hypotheses: biologically rich areas that support high human population densities co-occur with areas of high biodiversity (productivity); biodiversity decreases monotonically with increasing human activities (ecosystem...

  17. Emergence of the global research alliance on agricultural greenhouse gases

    USDA-ARS?s Scientific Manuscript database

    Increasing human population pressure on the Earth is of great concern and a key reason why agricultural and natural resource sciences must be fully engaged to develop solutions for a sustainable future. Increasing population puts pressure on the demand for food, clean water, healthy soil, and a sta...

  18. Future development of animal welfare science and use of new technologies

    USDA-ARS?s Scientific Manuscript database

    The expected human population growth to 9 billion people by 2050 will impact all animals with which we share this planet. We will see more farm animals, greater companion animal ownership, increasing feral populations, increased use of laboratory animals and threatened wildlife species diversity, im...

  19. Climate change and environmental impacts on maternal and newborn health with focus on Arctic populations.

    PubMed

    Rylander, Charlotta; Odland, Jon Ø; Sandanger, Torkjel M

    2011-01-01

    In 2007, the Intergovernmental Panel on Climate Change (IPCC) presented a report on global warming and the impact of human activities on global warming. Later the Lancet commission identified six ways human health could be affected. Among these were not environmental factors which are also believed to be important for human health. In this paper we therefore focus on environmental factors, climate change and the predicted effects on maternal and newborn health. Arctic issues are discussed specifically considering their exposure and sensitivity to long range transported contaminants. Considering that the different parts of pregnancy are particularly sensitive time periods for the effects of environmental exposure, this review focuses on the impacts on maternal and newborn health. Environmental stressors known to affects human health and how these will change with the predicted climate change are addressed. Air pollution and food security are crucial issues for the pregnant population in a changing climate, especially indoor climate and food security in Arctic areas. The total number of environmental factors is today responsible for a large number of the global deaths, especially in young children. Climate change will most likely lead to an increase in this number. Exposure to the different environmental stressors especially air pollution will in most parts of the world increase with climate change, even though some areas might face lower exposure. Populations at risk today are believed to be most heavily affected. As for the persistent organic pollutants a warming climate leads to a remobilisation and a possible increase in food chain exposure in the Arctic and thus increased risk for Arctic populations. This is especially the case for mercury. The perspective for the next generations will be closely connected to the expected temperature changes; changes in housing conditions; changes in exposure patterns; predicted increased exposure to Mercury because of increased emissions and increased biological availability. A number of environmental stressors are predicted to increase with climate change and increasingly affecting human health. Efforts should be put on reducing risk for the next generation, thus global politics and research effort should focus on maternal and newborn health.

  20. Effects of habitat characteristics on the growth of carrier population leading to increased spread of typhoid fever: a model.

    PubMed

    Shukla, J B; Goyal, Ashish; Singh, Shikha; Chandra, Peeyush

    2014-06-01

    In this paper, a non-linear model is proposed and analyzed to study the effects of habitat characteristics favoring logistically growing carrier population leading to increased spread of typhoid fever. It is assumed that the cumulative density of habitat characteristics and the density of carrier population are governed by logistic models; the growth rate of the former increases as the density of human population increases. The model is analyzed by stability theory of differential equations and computer simulation. The analysis shows that as the density of the infective carrier population increases due to habitat characteristics, the spread of typhoid fever increases in comparison with the case without such factors. Copyright © 2013 Ministry of Health, Saudi Arabia. Published by Elsevier Ltd. All rights reserved.

  1. Resource use and the environment

    USDA-ARS?s Scientific Manuscript database

    The human population will increase 50% by 2100 and the demand for resources and resulting negative environmental impacts will increase in the future if humans continue to use resources anywhere near the current rate. Producing enough food for the future is a daunting task, but to do so without deple...

  2. Toward a Sustainable Future. Rancho Santiago College Annual Faculty Lecture (3rd, November 15, 1989).

    ERIC Educational Resources Information Center

    Bates, Richard D.

    This lecture recounts personal experiences and discusses environmental issues that invoked a desire to teach about the things threatening the earth. Human population growth is cited as the first and foremost environmental challenge in the 20th century. A J-shaped curve is used to illustrate an increase in human population. The relationship between…

  3. Landscape and patch-level factors influence bird communities in an urbanized tropical island

    Treesearch

    Marcela Suarez-Rubio; John R. Thomlinson

    2009-01-01

    As human population continues to increase and intensification of human land use escalates, it is important to address the role of urban forest patches in supporting bird communities. We related bird species richness and community assemblage to landscape- and patch- level factors in 40 forest patches in the densely populated metropolitan area of San Juan, Puerto Rico....

  4. A review of the health impacts of barium from natural and anthropogenic exposure.

    PubMed

    Kravchenko, Julia; Darrah, Thomas H; Miller, Richard K; Lyerly, H Kim; Vengosh, Avner

    2014-08-01

    There is an increasing public awareness of the relatively new and expanded industrial barium uses which are potential sources of human exposure (e.g., a shale gas development that causes an increased awareness of environmental exposures to barium). However, absorption of barium in exposed humans and a full spectrum of its health effects, especially among chronically exposed to moderate and low doses of barium populations, remain unclear. We suggest a systematic literature review (from 1875 to 2014) on environmental distribution of barium, its bioaccumulation, and potential and proven health impacts (in animal models and humans) to provide the information that can be used for optimization of future experimental and epidemiological studies and developing of mitigative and preventive strategies to minimize negative health effects in exposed populations. The potential health effects of barium exposure are largely based on animal studies, while epidemiological data for humans, specifically for chronic low-level exposures, are sparse. The reported health effects include cardiovascular and kidney diseases, metabolic, neurological, and mental disorders. Age, race, dietary patterns, behavioral risks (e.g., smoking), use of medications (those that interfere with absorbed barium in human organism), and specific physiological status (e.g., pregnancy) can modify barium effects on human health. Identifying, evaluating, and predicting the health effects of chronic low-level and moderate-level barium exposures in humans is challenging: Future research is needed to develop an understanding of barium bioaccumulation in order to mitigate its potential health impacts in various exposured populations. Further, while occupationally exposed at-risk populations exist, it is also important to identify potentially vulnerable subgroups among non-occupationally exposed populations (e.g., elderly, pregnant women, children) who are at higher risk of barium exposure from drinking water and food.

  5. Guide to Population Issues for Students and Teachers [and] Curriculum Guide.

    ERIC Educational Resources Information Center

    Facing the Future, Lopez Island, WA.

    As the world grapples with increasing environmental, social, and security problems, population is rarely considered a cause or contributing factor. The relationship of population to the human condition, and to the condition of the Earth, is often subtle and complex. But population growth affects almost every aspect of life from education to…

  6. Disrupting evolutionary processes: the effect of habitat fragmentation on collared lizards in the Missouri Ozarks.

    PubMed

    Templeton, A R; Robertson, R J; Brisson, J; Strasburg, J

    2001-05-08

    Humans affect biodiversity at the genetic, species, community, and ecosystem levels. This impact on genetic diversity is critical, because genetic diversity is the raw material of evolutionary change, including adaptation and speciation. Two forces affecting genetic variation are genetic drift (which decreases genetic variation within but increases genetic differentiation among local populations) and gene flow (which increases variation within but decreases differentiation among local populations). Humans activities often augment drift and diminish gene flow for many species, which reduces genetic variation in local populations and prevents the spread of adaptive complexes outside their population of origin, thereby disrupting adaptive processes both locally and globally within a species. These impacts are illustrated with collared lizards (Crotaphytus collaris) in the Missouri Ozarks. Forest fire suppression has reduced habitat and disrupted gene flow in this lizard, thereby altering the balance toward drift and away from gene flow. This balance can be restored by managed landscape burns. Some have argued that, although human-induced fragmentation disrupts adaptation, it will also ultimately produce new species through founder effects. However, population genetic theory and experiments predict that most fragmentation events caused by human activities will facilitate not speciation, but local extinction. Founder events have played an important role in the macroevolution of certain groups, but only when ecological opportunities are expanding rather than contracting. The general impact of human activities on genetic diversity disrupts or diminishes the capacity for adaptation, speciation, and macroevolutionary change. This impact will ultimately diminish biodiversity at all levels.

  7. Human impacts on 20th century fire dynamics and implications for global carbon and water trajectories

    NASA Astrophysics Data System (ADS)

    Li, F.; Lawrence, D. M.; Bond-Lamberty, B. P.

    2017-12-01

    Fire is a fundamental Earth system process and the primary ecosystem disturbance on the global scale. It affects carbon and water cycles through its impact on terrestrial ecosystems, and at the same time, is regulated by weather and climate, vegetation characteristics, and, importantly, human ignition and efforts to suppress fires (i.e., the direct human effect on fire). Here, we utilize the Community Land Model version 4.5 (CLM4.5) to generate a quantitative understanding of the impacts on fire dynamics and associated carbon and water cycling that can be attributed to changes in human ignition and suppression over the 20th century. We find that the net impact of increases in human ignition and suppression significantly reduce the 20th century averaged global burned area by 38 Mha/yr. The reduction increases since 1920, rising to 103 Mha/yr less burned area at the end of the century. Land carbon gain is weakened by 17% over the 20th century, mainly due to increased human deforestation fires and associated escape fires (i.e., degradation fires) in the tropical humid forests, even though the decrease in burned area in many other regions due to human fire suppression acts to increase land carbon gain. The direct human effect on fire also weakens the 20th century upward trend of global runoff by 6%, and enhances the upward trend in global evaportranspiration since 1945 by 7%. In addition, the above impacts in densely populated, highly developed (if population density > 0.1 person/km2), or moderately populated and developed regions are of opposite sign to those in other regions. Our study suggests that particular attention should be paid to human deforestation and degradation fires in the tropical humid forests when reconstructing and projecting fire carbon emissions and net atmosphere-land carbon exchange and estimating resultant impacts of direct human effect on fire.

  8. Demographic and Phenotypic Effects of Human Mediated Trophic Subsidy on a Large Australian Lizard (Varanus varius): Meal Ticket or Last Supper?

    PubMed Central

    Jessop, Tim S.; Smissen, Peter; Scheelings, Franciscus; Dempster, Tim

    2012-01-01

    Humans are increasingly subsidizing and altering natural food webs via changes to nutrient cycling and productivity. Where human trophic subsidies are concentrated and persistent within natural environments, their consumption could have complex consequences for wild animals through altering habitat preferences, phenotypes and fitness attributes that influence population dynamics. Human trophic subsidies conceptually create both costs and benefits for animals that receive increased calorific and altered nutritional inputs. Here, we evaluated the effects of a common terrestrial human trophic subsidies, human food refuse, on population and phenotypic (comprising morphological and physiological health indices) parameters of a large predatory lizard (∼2 m length), the lace monitor (Varanus varius), in southern Australia by comparison with individuals not receiving human trophic subsidies. At human trophic subsidies sites, lizards were significantly more abundant and their sex ratio highly male biased compared to control sites in natural forest. Human trophic subsidies recipient lizards were significantly longer, heavier and in much greater body condition. Blood parasites were significantly lower in human trophic subsidies lizards. Collectively, our results imply that human trophic subsidized sites were especially attractive to adult male lace monitors and had large phenotypic effects. However, we cannot rule out that the male-biased aggregations of large monitors at human trophic subsidized sites could lead to reductions in reproductive fitness, through mate competition and offspring survival, and through greater exposure of eggs and juveniles to predation. These possibilities could have negative population consequences. Aggregations of these large predators may also have flow on effects to surrounding food web dynamics through elevated predation levels. Given that flux of energy and nutrients into food webs is central to the regulation of populations and their communities, we advocate further studies of human trophic subsidies be undertaken to evaluate the potentially large ecological implications of this significant human environmental alteration. PMID:22509271

  9. Relationships of Modeled Nitrogen Loads with Marsh Fish in the Narragansett Bay Estuary, Rhode Island

    EPA Science Inventory

    The human population and associated watershed development has risen steadily since the 1850s in Rhode Island, USA. With these increases, human-derived wastewater has also risen dramatically, resulting in increasing watershed nitrogen loads to estuarine systems. In this study, we...

  10. The episode of genetic drift defining the migration of humans out of Africa is derived from a large east African population size.

    PubMed

    Elhassan, Nuha; Gebremeskel, Eyoab Iyasu; Elnour, Mohamed Ali; Isabirye, Dan; Okello, John; Hussien, Ayman; Kwiatksowski, Dominic; Hirbo, Jibril; Tishkoff, Sara; Ibrahim, Muntaser E

    2014-01-01

    Human genetic variation particularly in Africa is still poorly understood. This is despite a consensus on the large African effective population size compared to populations from other continents. Based on sequencing of the mitochondrial Cytochrome C Oxidase subunit II (MT-CO2), and genome wide microsatellite data we observe evidence suggesting the effective size (Ne) of humans to be larger than the current estimates, with a foci of increased genetic diversity in east Africa, and a population size of east Africans being at least 2-6 fold larger than other populations. Both phylogenetic and network analysis indicate that east Africans possess more ancestral lineages in comparison to various continental populations placing them at the root of the human evolutionary tree. Our results also affirm east Africa as the likely spot from which migration towards Asia has taken place. The study reflects the spectacular level of sequence variation within east Africans in comparison to the global sample, and appeals for further studies that may contribute towards filling the existing gaps in the database. The implication of these data to current genomic research, as well as the need to carry out defined studies of human genetic variation that includes more African populations; particularly east Africans is paramount.

  11. Echinococcosis: Control and Prevention.

    PubMed

    Craig, P S; Hegglin, D; Lightowlers, M W; Torgerson, P R; Wang, Q

    2017-01-01

    Human cystic echinococcosis (CE) has been eliminated or significantly reduced as a public health problem in several previously highly endemic regions. This has been achieved by the long-term application of prevention and control measures primarily targeted to deworming dogs, health education, meat inspection, and effective surveillance in livestock and human populations. Human CE, however, remains a serious neglected zoonotic disease in many resource-poor pastoral regions. The incidence of human alveolar echinococcosis (AE) has increased in continental Europe and is a major public health problem in parts of Eurasia. Better understanding of wildlife ecology for fox and small mammal hosts has enabled targeted anthelmintic baiting of fox populations and development of spatially explicit models to predict population dynamics for key intermediate host species and human AE risk in endemic landscapes. Challenges that remain for echinococcosis control include effective intervention in resource-poor communities, better availability of surveillance tools, optimal application of livestock vaccination, and management and ecology of dog and wildlife host populations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Population growth, human development, and deforestation in biodiversity hotspots.

    PubMed

    Jha, S; Bawa, K S

    2006-06-01

    Human population and development activities affect the rate of deforestation in biodiversity hotspots. We quantified the effect of human population growth and development on rates of deforestation and analyzed the relationship between these causal factors in the 1980s and 1990s. We compared the averages of population growth, human development index (HDI, which measures income, health, and education), and deforestation rate and computed correlations among these variables for countries that contain biodiversity hotspots. When population growth was high and HDI was low there was a high rate of deforestation, but when HDI was high, rate of deforestation was low, despite high population growth. The correlation among variables was significant for the 1990s but not for the 1980s. The relationship between population growth and HDI had a regional pattern that reflected the historical process of development. Based on the changes in HDI and deforestation rate over time, we identified two drivers of deforestation: policy choice and human-development constraints. Policy choices that disregard conservation may cause the loss of forests even in countries that are relatively developed. Lack of development in other countries, on the other hand, may increase the pressure on forests to meet the basic needs of the human population. Deforestation resulting from policy choices may be easier to fix than deforestation arising from human development constraints. To prevent deforestation in the countries that have such constraints, transfer of material and intellectual resources from developed countries may be needed. Popular interest in sustainable development in developed countries can facilitate the transfer of these resources.

  13. Climate, CO2 and human population impacts on global wildfire emissions

    NASA Astrophysics Data System (ADS)

    Knorr, W.; Jiang, L.; Arneth, A.

    2016-01-01

    Wildfires are by far the largest contributor to global biomass burning and constitute a large global source of atmospheric traces gases and aerosols. Such emissions have a considerable impact on air quality and constitute a major health hazard. Biomass burning also influences the radiative balance of the atmosphere and is thus not only of societal, but also of significant scientific interest. There is a common perception that climate change will lead to an increase in emissions as hot and dry weather events that promote wildfire will become more common. However, even though a few studies have found that the inclusion of CO2 fertilisation of photosynthesis and changes in human population patterns will tend to somewhat lower predictions of future wildfire emissions, no such study has included full ensemble ranges of both climate predictions and population projections, including the effect of different degrees of urbanisation.

    Here, we present a series of 124 simulations with the LPJ-GUESS-SIMFIRE global dynamic vegetation-wildfire model, including a semi-empirical formulation for the prediction of burned area based on fire weather, fuel continuity and human population density. The simulations use Climate Model Intercomparison Project 5 (CMIP5) climate predictions from eight Earth system models. These were combined with two Representative Concentration Pathways (RCPs) and five scenarios of future human population density based on the series of Shared Socioeconomic Pathways (SSPs) to assess the sensitivity of emissions to the effect of climate, CO2 and humans. In addition, two alternative parameterisations of the semi-empirical burned-area model were applied. Contrary to previous work, we find no clear future trend of global wildfire emissions for the moderate emissions and climate change scenario based on the RCP 4.5. Only historical population change introduces a decline by around 15 % since 1900. Future emissions could either increase for low population growth and fast urbanisation, or continue to decline for high population growth and slow urbanisation. Only for high future climate change (RCP8.5), wildfire emissions start to rise again after ca. 2020 but are unlikely to reach the levels of 1900 by the end of the 21st century. We find that climate warming will generally increase the risk of fire, but that this is only one of several equally important factors driving future levels of wildfire emissions, which include population change, CO2 fertilisation causing woody thickening, increased productivity and fuel load and faster litter turnover in a warmer climate.

  14. Population Skeletons in the Environmental Closet

    ERIC Educational Resources Information Center

    Hardin, Garrett

    1972-01-01

    An evaluation of the Commoner--Ehrlich and Holdren controversy regarding the importance of population growth as a contributing factor to the increasing environmental impact of humans. (See Bulletin of the Atomic Scientists, May, 1972.) (AL)

  15. Human Health and Toxic Cyanobacteria – What do we know?

    EPA Science Inventory

    Human Health and Toxic Cyanobacteria – What do we know?Elizabeth D. HilbornWarm, eutrophic surface water systems support the development of toxic cyanobacteria blooms in North Carolina and worldwide. These conditions are increasing with expanding human populations and clima...

  16. The Intrusion of Human Population into Forest and Range Lands of California

    Treesearch

    Ted D. Bradshaw

    1987-01-01

    Demographic and economic growth are pushing deeper into California's forest and range lands, making effective fire protection and traditional industrial uses of the land more difficult. Urban forces that will increase the difficulties in the future include: increasing urban population pressures, selective migration, low-priced housing, adequate infrastructure,...

  17. Reconstructing the history of a fragmented and heavily exploited red deer population using ancient and contemporary DNA.

    PubMed

    Rosvold, Jørgen; Røed, Knut H; Hufthammer, Anne Karin; Andersen, Reidar; Stenøien, Hans K

    2012-09-26

    Red deer (Cervus elaphus) have been an important human resource for millennia, experiencing intensive human influence through habitat alterations, hunting and translocation of animals. In this study we investigate a time series of ancient and contemporary DNA from Norwegian red deer spanning about 7,000 years. Our main aim was to investigate how increasing agricultural land use, hunting pressure and possibly human mediated translocation of animals have affected the genetic diversity on a long-term scale. We obtained mtDNA (D-loop) sequences from 73 ancient specimens. These show higher genetic diversity in ancient compared to extant samples, with the highest diversity preceding the onset of agricultural intensification in the Early Iron Age. Using standard diversity indices, Bayesian skyline plot and approximate Bayesian computation, we detected a population reduction which was more prolonged than, but not as severe as, historic documents indicate. There are signs of substantial changes in haplotype frequencies primarily due to loss of haplotypes through genetic drift. There is no indication of human mediated translocations into the Norwegian population. All the Norwegian sequences show a western European origin, from which the Norwegian lineage diverged approximately 15,000 years ago. Our results provide direct insight into the effects of increasing habitat fragmentation and human hunting pressure on genetic diversity and structure of red deer populations. They also shed light on the northward post-glacial colonisation process of red deer in Europe and suggest increased precision in inferring past demographic events when including both ancient and contemporary DNA.

  18. Cultural innovations and demographic change.

    PubMed

    Richerson, Peter J; Boyd, Robert; Bettinger, Robert L

    2009-04-01

    Demography plays a large role in cultural evolution through its effects on the effective rate of innovation. If we assume that useful inventions are rare, then small isolated societies will have low rates of invention. In small populations, complex technology will tend to be lost as a result of random loss or incomplete transmission (the Tasmanian effect). Large populations have more inventors and are more resistant to loss by chance. If human populations can grow freely, then a population-technology-population positive feedback should occur such that human societies reach a stable growth path on which the rate of growth of technology is limited by the rate of invention. This scenario fits the Holocene to a first approximation, but the late Pleistocene is a great puzzle. Large-brained hominins existed in Africa and west Eurasia for perhaps 150,000 years with, at best, slow rates of technical innovation. The most sophisticated societies of the last glacial period appear after 50,000 years ago and were apparently restricted to west and north-central Eurasia and North Africa. These patterns have no simple, commonly accepted explanation. We argue that increased high-frequency climate change around 70,000-50,000 years ago may have tipped the balance between humans and their competitor-predators, such as lions and wolves, in favor of humans. At the same time, technically sophisticated hunters would tend to overharvest their prey. Perhaps the ephemeral appearance of complex tools and symbolic artifacts in Africa after 100,000 years ago resulted from hunting inventions that allowed human populations to expand temporarily before prey overexploitation led to human population and technology collapse. Sustained human populations of moderate size using distinctively advanced Upper Paleolithic artifacts may have existed in west Eurasia because cold, continental northeastern Eurasia-Beringia acted as a protected reserve for prey populations.

  19. Public health significance of zoonotic Cryptosporidium species in wildlife: Critical insights into better drinking water management.

    PubMed

    Zahedi, Alireza; Paparini, Andrea; Jian, Fuchun; Robertson, Ian; Ryan, Una

    2016-04-01

    Cryptosporidium is an enteric parasite that is transmitted via the faecal-oral route, water and food. Humans, wildlife and domestic livestock all potentially contribute Cryptosporidium to surface waters. Human encroachment into natural ecosystems has led to an increase in interactions between humans, domestic animals and wildlife populations. Increasing numbers of zoonotic diseases and spill over/back of zoonotic pathogens is a consequence of this anthropogenic disturbance. Drinking water catchments and water reservoir areas have been at the front line of this conflict as they can be easily contaminated by zoonotic waterborne pathogens. Therefore, the epidemiology of zoonotic species of Cryptosporidium in free-ranging and captive wildlife is of increasing importance. This review focuses on zoonotic Cryptosporidium species reported in global wildlife populations to date, and highlights their significance for public health and the water industry.

  20. Holocene fluctuations in human population demonstrate repeated links to food production and climate

    PubMed Central

    Colledge, Sue; Fuller, Dorian; Fyfe, Ralph; Shennan, Stephen; Stevens, Chris

    2017-01-01

    We consider the long-term relationship between human demography, food production, and Holocene climate via an archaeological radiocarbon date series of unprecedented sampling density and detail. There is striking consistency in the inferred human population dynamics across different regions of Britain and Ireland during the middle and later Holocene. Major cross-regional population downturns in population coincide with episodes of more abrupt change in North Atlantic climate and witness societal responses in food procurement as visible in directly dated plants and animals, often with moves toward hardier cereals, increased pastoralism, and/or gathered resources. For the Neolithic, this evidence questions existing models of wholly endogenous demographic boom–bust. For the wider Holocene, it demonstrates that climate-related disruptions have been quasi-periodic drivers of societal and subsistence change. PMID:29158411

  1. The Rising Tide of Antimicrobial Resistance in Aquaculture: Sources, Sinks and Solutions

    PubMed Central

    Watts, Joy E. M.; Schreier, Harold J.; Lanska, Lauma; Hale, Michelle S.

    2017-01-01

    As the human population increases there is an increasing reliance on aquaculture to supply a safe, reliable, and economic supply of food. Although food production is essential for a healthy population, an increasing threat to global human health is antimicrobial resistance. Extensive antibiotic resistant strains are now being detected; the spread of these strains could greatly reduce medical treatment options available and increase deaths from previously curable infections. Antibiotic resistance is widespread due in part to clinical overuse and misuse; however, the natural processes of horizontal gene transfer and mutation events that allow genetic exchange within microbial populations have been ongoing since ancient times. By their nature, aquaculture systems contain high numbers of diverse bacteria, which exist in combination with the current and past use of antibiotics, probiotics, prebiotics, and other treatment regimens—singularly or in combination. These systems have been designated as “genetic hotspots” for gene transfer. As our reliance on aquaculture grows, it is essential that we identify the sources and sinks of antimicrobial resistance, and monitor and analyse the transfer of antimicrobial resistance between the microbial community, the environment, and the farmed product, in order to better understand the implications to human and environmental health. PMID:28587172

  2. The Rising Tide of Antimicrobial Resistance in Aquaculture: Sources, Sinks and Solutions.

    PubMed

    Watts, Joy E M; Schreier, Harold J; Lanska, Lauma; Hale, Michelle S

    2017-06-01

    As the human population increases there is an increasing reliance on aquaculture to supply a safe, reliable, and economic supply of food. Although food production is essential for a healthy population, an increasing threat to global human health is antimicrobial resistance. Extensive antibiotic resistant strains are now being detected; the spread of these strains could greatly reduce medical treatment options available and increase deaths from previously curable infections. Antibiotic resistance is widespread due in part to clinical overuse and misuse; however, the natural processes of horizontal gene transfer and mutation events that allow genetic exchange within microbial populations have been ongoing since ancient times. By their nature, aquaculture systems contain high numbers of diverse bacteria, which exist in combination with the current and past use of antibiotics, probiotics, prebiotics, and other treatment regimens-singularly or in combination. These systems have been designated as "genetic hotspots" for gene transfer. As our reliance on aquaculture grows, it is essential that we identify the sources and sinks of antimicrobial resistance, and monitor and analyse the transfer of antimicrobial resistance between the microbial community, the environment, and the farmed product, in order to better understand the implications to human and environmental health.

  3. An indigenous religious ritual selects for resistance to a toxicant in a livebearing fish.

    PubMed

    Tobler, M; Culumber, Z W; Plath, M; Winemiller, K O; Rosenthal, G G

    2011-04-23

    Human-induced environmental change can affect the evolutionary trajectory of populations. In Mexico, indigenous Zoque people annually introduce barbasco, a fish toxicant, into the Cueva del Azufre to harvest fish during a religious ceremony. Here, we investigated tolerance to barbasco in fish from sites exposed and unexposed to the ritual. We found that barbasco tolerance increases with body size and differs between the sexes. Furthermore, fish from sites exposed to the ceremony had a significantly higher tolerance. Consequently, the annual ceremony may not only affect population structure and gene flow among habitat types, but the increased tolerance in exposed fish may indicate adaptation to human cultural practices in a natural population on a very small spatial scale.

  4. An indigenous religious ritual selects for resistance to a toxicant in a livebearing fish

    PubMed Central

    Tobler, M.; Culumber, Z. W.; Plath, M.; Winemiller, K. O.; Rosenthal, G. G.

    2011-01-01

    Human-induced environmental change can affect the evolutionary trajectory of populations. In Mexico, indigenous Zoque people annually introduce barbasco, a fish toxicant, into the Cueva del Azufre to harvest fish during a religious ceremony. Here, we investigated tolerance to barbasco in fish from sites exposed and unexposed to the ritual. We found that barbasco tolerance increases with body size and differs between the sexes. Furthermore, fish from sites exposed to the ceremony had a significantly higher tolerance. Consequently, the annual ceremony may not only affect population structure and gene flow among habitat types, but the increased tolerance in exposed fish may indicate adaptation to human cultural practices in a natural population on a very small spatial scale. PMID:20826470

  5. Growth anomalies on the coral genera Acropora and Porites are strongly associated with host density and human population size across the Indo-Pacific

    USGS Publications Warehouse

    Aeby, Greta S.; Williams, Gareth J.; Franklin, Erik C.; Haapkyla, Jessica; Harvell, C. Drew; Neale, Stephen; Page, Cathie A.; Raymundo, Laurie; Vargas-Angel, Bernardo; Willis, Bette L.; Work, Thierry M.; Davy, Simon K.

    2011-01-01

    Growth anomalies (GAs) are common, tumor-like diseases that can cause significant morbidity and decreased fecundity in the major Indo-Pacific reef-building coral genera, Acropora and Porites. GAs are unusually tractable for testing hypotheses about drivers of coral disease because of their pan-Pacific distributions, relatively high occurrence, and unambiguous ease of identification. We modeled multiple disease-environment associations that may underlie the prevalence of Acropora growth anomalies (AGA) (n = 304 surveys) and Porites growth anomalies (PGA) (n = 602 surveys) from across the Indo-Pacific. Nine predictor variables were modeled, including coral host abundance, human population size, and sea surface temperature and ultra-violet radiation anomalies. Prevalence of both AGAs and PGAs were strongly host density-dependent. PGAs additionally showed strong positive associations with human population size. Although this association has been widely posited, this is one of the first broad-scale studies unambiguously linking a coral disease with human population size. These results emphasize that individual coral diseases can show relatively distinct patterns of association with environmental predictors, even in similar diseases (growth anomalies) found on different host genera (Acropora vs. Porites). As human densities and environmental degradation increase globally, the prevalence of coral diseases like PGAs could increase accordingly, halted only perhaps by declines in host density below thresholds required for disease establishment.

  6. Growth Anomalies on the Coral Genera Acropora and Porites Are Strongly Associated with Host Density and Human Population Size across the Indo-Pacific

    PubMed Central

    Franklin, Erik C.; Haapkyla, Jessica; Harvell, C. Drew; Neale, Stephen; Page, Cathie A.; Raymundo, Laurie; Vargas-Ángel, Bernardo; Willis, Bette L.; Work, Thierry M.; Davy, Simon K.

    2011-01-01

    Growth anomalies (GAs) are common, tumor-like diseases that can cause significant morbidity and decreased fecundity in the major Indo-Pacific reef-building coral genera, Acropora and Porites. GAs are unusually tractable for testing hypotheses about drivers of coral disease because of their pan-Pacific distributions, relatively high occurrence, and unambiguous ease of identification. We modeled multiple disease-environment associations that may underlie the prevalence of Acropora growth anomalies (AGA) (n = 304 surveys) and Porites growth anomalies (PGA) (n = 602 surveys) from across the Indo-Pacific. Nine predictor variables were modeled, including coral host abundance, human population size, and sea surface temperature and ultra-violet radiation anomalies. Prevalence of both AGAs and PGAs were strongly host density-dependent. PGAs additionally showed strong positive associations with human population size. Although this association has been widely posited, this is one of the first broad-scale studies unambiguously linking a coral disease with human population size. These results emphasize that individual coral diseases can show relatively distinct patterns of association with environmental predictors, even in similar diseases (growth anomalies) found on different host genera (Acropora vs. Porites). As human densities and environmental degradation increase globally, the prevalence of coral diseases like PGAs could increase accordingly, halted only perhaps by declines in host density below thresholds required for disease establishment. PMID:21365011

  7. Fertility, Human Capital, and Economic Growth over the Demographic Transition

    PubMed Central

    Mason, Andrew

    2009-01-01

    Do low fertility and population aging lead to economic decline if couples have fewer children, but invest more in each child? By addressing this question, this article extends previous work in which the authors show that population aging leads to an increased demand for wealth that can, under some conditions, lead to increased capital per worker and higher per capita consumption. This article is based on an overlapping generations (OLG) model which highlights the quantity–quality tradeoff and the links between human capital investment and economic growth. It incorporates new national level estimates of human capital investment produced by the National Transfer Accounts project. Simulation analysis is employed to show that, even in the absence of the capital dilution effect, low fertility leads to higher per capita consumption through human capital accumulation, given plausible model parameters. PMID:20495605

  8. Conservation conflicts across Africa.

    PubMed

    Balmford, A; Moore, J L; Brooks, T; Burgess, N; Hansen, L A; Williams, P; Rahbek, C

    2001-03-30

    There is increasing evidence that areas of outstanding conservation importance may coincide with dense human settlement or impact. We tested the generality of these findings using 1 degree-resolution data for sub-Saharan Africa. We find that human population density is positively correlated with species richness of birds, mammals, snakes, and amphibians. This association holds for widespread, narrowly endemic, and threatened species and looks set to persist in the face of foreseeable population growth. Our results contradict earlier expectations of low conflict based on the idea that species richness decreases and human impact increases with primary productivity. We find that across Africa, both variables instead exhibit unimodal relationships with productivity. Modifying priority-setting to take account of human density shows that, at this scale, conflicts between conservation and development are not easily avoided, because many densely inhabited grid cells contain species found nowhere else.

  9. Population viability analysis of the Florida manatee (Trichechus manatus latirostris), 1976-1991

    USGS Publications Warehouse

    Marmontel, M.; Humphrey, S.R.; O'Shea, T.J.

    1997-01-01

    Recent development of age-determination techniques for Florida manatees (Trichechus manatus latirostris) has permitted derivation of age-specific data on reproduction and survival of a sample of 1212 carcasses obtained throughout Florida from 1976–1991. Population viability analysis using these data projects a slightly negative growth rate (−0.003) and an unacceptably low probability of persistence (0.44) over 1000 years. The main factors affecting population projections were adult survival and fecundity. A 10% increase in adult mortality would drive the population to extinction over a 1000-year time scale, whereas a 10% decrease in adult mortality would allow slow population growth. A 10% decrease in reproduction would also result in extinction. We conclude that management must focus on retaining and improving the conditions under which manatee demography operates. The major identified agent of mortality is boat-manatee collisions, and rapidly increasing numbers of humans and registered boats portend an increase in manatee mortality. Zoning of manatee-occupied waters for reductions in boating activity and speed is essential to safeguard the manatee population. If boating regulations being implemented by the state of Florida in each of 13 key coastal counties are completed, enforced, and effective, manatees and human recreation could coexist indefinitely. If regulation is unsuccessful, the Florida manatee population is likely to decline slowly toward extinction.

  10. Concern With Environmental Deterioration and Attitudes Toward Population Limitation

    ERIC Educational Resources Information Center

    Barnett, Larry D.

    1970-01-01

    Analysis of Gallup Poll data of Junuary 1969 reveals weak association between concern about environmental deterioration and the recognition of need for eventual limitation of human population. Suggests that to increase favorable attitudes to population control, role of overpopulation in causing environmental deterioration needs to be presented to…

  11. Genetic analysis shows low levels of hybridization between African wildcats (Felis silvestris lybica) and domestic cats (F. s. catus) in South Africa

    PubMed Central

    Le Roux, Johannes J; Foxcroft, Llewellyn C; Herbst, Marna; MacFadyen, Sandra

    2015-01-01

    Hybridization between domestic and wild animals is a major concern for biodiversity conservation, and as habitats become increasingly fragmented, conserving biodiversity at all levels, including genetic, becomes increasingly important. Except for tropical forests and true deserts, African wildcats occur across the African continent; however, almost no work has been carried out to assess its genetic status and extent of hybridization with domestic cats. For example, in South Africa it has been argued that the long-term viability of maintaining pure wildcat populations lies in large protected areas only, isolated from human populations. Two of the largest protected areas in Africa, the Kgalagadi Transfrontier and Kruger National Parks, as well as the size of South Africa and range of landscape uses, provide a model situation to assess how habitat fragmentation and heterogeneity influences the genetic purity of African wildcats. Using population genetic and home range data, we examined the genetic purity of African wildcats and their suspected hybrids across South Africa, including areas within and outside of protected areas. Overall, we found African wildcat populations to be genetically relatively pure, but instances of hybridization and a significant relationship between the genetic distinctiveness (purity) of wildcats and human population pressure were evident. The genetically purest African wildcats were found in the Kgalagadi Transfrontier Park, while samples from around Kruger National Park showed cause for concern, especially combined with the substantial human population density along the park's boundary. While African wildcat populations in South Africa generally appear to be genetically pure, with low levels of hybridization, our genetic data do suggest that protected areas may play an important role in maintaining genetic purity by reducing the likelihood of contact with domestic cats. We suggest that approaches such as corridors between protected areas are unlikely to remain effective for wildcat conservation, as the proximity to human settlements around these areas is projected to increase the wild/domestic animal interface. Thus, large, isolated protected areas will become increasingly important for wildcat conservation and efforts need to be made to prevent introduction of domestic cats into these areas. PMID:25691958

  12. Genetic analysis shows low levels of hybridization between African wildcats (Felis silvestris lybica) and domestic cats (F. s. catus) in South Africa.

    PubMed

    Le Roux, Johannes J; Foxcroft, Llewellyn C; Herbst, Marna; MacFadyen, Sandra

    2015-01-01

    Hybridization between domestic and wild animals is a major concern for biodiversity conservation, and as habitats become increasingly fragmented, conserving biodiversity at all levels, including genetic, becomes increasingly important. Except for tropical forests and true deserts, African wildcats occur across the African continent; however, almost no work has been carried out to assess its genetic status and extent of hybridization with domestic cats. For example, in South Africa it has been argued that the long-term viability of maintaining pure wildcat populations lies in large protected areas only, isolated from human populations. Two of the largest protected areas in Africa, the Kgalagadi Transfrontier and Kruger National Parks, as well as the size of South Africa and range of landscape uses, provide a model situation to assess how habitat fragmentation and heterogeneity influences the genetic purity of African wildcats. Using population genetic and home range data, we examined the genetic purity of African wildcats and their suspected hybrids across South Africa, including areas within and outside of protected areas. Overall, we found African wildcat populations to be genetically relatively pure, but instances of hybridization and a significant relationship between the genetic distinctiveness (purity) of wildcats and human population pressure were evident. The genetically purest African wildcats were found in the Kgalagadi Transfrontier Park, while samples from around Kruger National Park showed cause for concern, especially combined with the substantial human population density along the park's boundary. While African wildcat populations in South Africa generally appear to be genetically pure, with low levels of hybridization, our genetic data do suggest that protected areas may play an important role in maintaining genetic purity by reducing the likelihood of contact with domestic cats. We suggest that approaches such as corridors between protected areas are unlikely to remain effective for wildcat conservation, as the proximity to human settlements around these areas is projected to increase the wild/domestic animal interface. Thus, large, isolated protected areas will become increasingly important for wildcat conservation and efforts need to be made to prevent introduction of domestic cats into these areas.

  13. Human whole body cold adaptation.

    PubMed

    Daanen, Hein A M; Van Marken Lichtenbelt, Wouter D

    2016-01-01

    Reviews on whole body human cold adaptation generally do not distinguish between population studies and dedicated acclimation studies, leading to confusing results. Population studies show that indigenous black Africans have reduced shivering thermogenesis in the cold and poor cold induced vasodilation in fingers and toes compared to Caucasians and Inuit. About 40,000 y after humans left Africa, natives in cold terrestrial areas seems to have developed not only behavioral adaptations, but also physiological adaptations to cold. Dedicated studies show that repeated whole body exposure of individual volunteers, mainly Caucasians, to severe cold results in reduced cold sensation but no major physiological changes. Repeated cold water immersion seems to slightly reduce metabolic heat production, while repeated exposure to milder cold conditions shows some increase in metabolic heat production, in particular non-shivering thermogenesis. In conclusion, human cold adaptation in the form of increased metabolism and insulation seems to have occurred during recent evolution in populations, but cannot be developed during a lifetime in cold conditions as encountered in temperate and arctic regions. Therefore, we mainly depend on our behavioral skills to live in and survive the cold.

  14. Human whole body cold adaptation

    PubMed Central

    Daanen, Hein A.M.; Van Marken Lichtenbelt, Wouter D.

    2016-01-01

    ABSTRACT Reviews on whole body human cold adaptation generally do not distinguish between population studies and dedicated acclimation studies, leading to confusing results. Population studies show that indigenous black Africans have reduced shivering thermogenesis in the cold and poor cold induced vasodilation in fingers and toes compared to Caucasians and Inuit. About 40,000 y after humans left Africa, natives in cold terrestrial areas seems to have developed not only behavioral adaptations, but also physiological adaptations to cold. Dedicated studies show that repeated whole body exposure of individual volunteers, mainly Caucasians, to severe cold results in reduced cold sensation but no major physiological changes. Repeated cold water immersion seems to slightly reduce metabolic heat production, while repeated exposure to milder cold conditions shows some increase in metabolic heat production, in particular non-shivering thermogenesis. In conclusion, human cold adaptation in the form of increased metabolism and insulation seems to have occurred during recent evolution in populations, but cannot be developed during a lifetime in cold conditions as encountered in temperate and arctic regions. Therefore, we mainly depend on our behavioral skills to live in and survive the cold. PMID:27227100

  15. Has Rift Valley fever virus evolved with increasing severity in human populations in East Africa?

    PubMed

    Baba, Marycelin; Masiga, Daniel K; Sang, Rosemary; Villinger, Jandouwe

    2016-06-22

    Rift Valley fever (RVF) outbreaks have occurred across eastern Africa from 1912 to 2010 approximately every 4-15 years, most of which have not been accompanied by significant epidemics in human populations. However, human epidemics during RVF outbreaks in eastern Africa have involved 478 deaths in 1998, 1107 reported cases with 350 deaths from 2006 to 2007 and 1174 cases with 241 deaths in 2008. We review the history of RVF outbreaks in eastern Africa to identify the epidemiological factors that could have influenced its increasing severity in humans. Diverse ecological factors influence outbreak frequency, whereas virus evolution has a greater impact on its virulence in hosts. Several factors could have influenced the lack of information on RVF in humans during earlier outbreaks, but the explosive nature of human RVF epidemics in recent years mirrors the evolutionary trend of the virus. Comparisons between isolates from different outbreaks have revealed an accumulation of genetic mutations and genomic reassortments that have diversified RVF virus genomes over several decades. The threat to humans posed by the diversified RVF virus strains increases the potential public health and socioeconomic impacts of future outbreaks. Understanding the shifting RVF epidemiology as determined by its evolution is key to developing new strategies for outbreak mitigation and prevention of future human RVF casualties.

  16. Evaluating mortality rates with a novel integrated framework for nonmonogamous species.

    PubMed

    Tenan, Simone; Iemma, Aaron; Bragalanti, Natalia; Pedrini, Paolo; De Barba, Marta; Randi, Ettore; Groff, Claudio; Genovart, Meritxell

    2016-12-01

    The conservation of wildlife requires management based on quantitative evidence, and especially for large carnivores, unraveling cause-specific mortalities and understanding their impact on population dynamics is crucial. Acquiring this knowledge is challenging because it is difficult to obtain robust long-term data sets on endangered populations and, usually, data are collected through diverse sampling strategies. Integrated population models (IPMs) offer a way to integrate data generated through different processes. However, IPMs are female-based models that cannot account for mate availability, and this feature limits their applicability to monogamous species only. We extended classical IPMs to a two-sex framework that allows investigation of population dynamics and quantification of cause-specific mortality rates in nonmonogamous species. We illustrated our approach by simultaneously modeling different types of data from a reintroduced, unhunted brown bear (Ursus arctos) population living in an area with a dense human population. In a population mainly driven by adult survival, we estimated that on average 11% of cubs and 61% of adults died from human-related causes. Although the population is currently not at risk, adult survival and thus population dynamics are driven by anthropogenic mortality. Given the recent increase of human-bear conflicts in the area, removal of individuals for management purposes and through poaching may increase, reversing the positive population growth rate. Our approach can be generalized to other species affected by cause-specific mortality and will be useful to inform conservation decisions for other nonmonogamous species, such as most large carnivores, for which data are scarce and diverse and thus data integration is highly desirable. © 2016 Society for Conservation Biology.

  17. Demographic controls of future global fire risk

    NASA Astrophysics Data System (ADS)

    Knorr, W.; Arneth, A.; Jiang, L.

    2016-08-01

    Wildfires are an important component of terrestrial ecosystem ecology but also a major natural hazard to societies, and their frequency and spatial distribution must be better understood. At a given location, risk from wildfire is associated with the annual fraction of burned area, which is expected to increase in response to climate warming. Until recently, however, only a few global studies of future fire have considered the effects of other important global environmental change factors such as atmospheric CO2 levels and human activities, and how these influence fires in different regions. Here, we contrast the impact of climate change and increasing atmospheric CO2 content on burned area with that of demographic dynamics, using ensembles of climate simulations combined with historical and projected population changes under different socio-economic development pathways for 1901-2100. Historically, humans notably suppressed wildfires. For future scenarios, global burned area will continue to decline under a moderate emissions scenario, except for low population growth and fast urbanization, but start to increase again from around mid-century under high greenhouse gas emissions. Contrary to common perception, we find that human exposure to wildfires increases in the future mainly owing to projected population growth in areas with frequent wildfires, rather than by a general increase in burned area.

  18. Largely Increased Nitrous Oxide Emission from Global Livestock Sector during 1860-2014: A geospatial-temporal analysis

    NASA Astrophysics Data System (ADS)

    Zhang, B.; Tian, H.; Xu, R.; Yang, J.; Pan, S.; Chen, G.

    2017-12-01

    The atmospheric concentration of nitrous oxide (N2O), one of major greenhouse gases, has increased over 121% compared with the preindustrial level, and most of the increase arises from anthropogenic activities. The shift of human diet and the ever-increasing human population pose a huge pressure on the demand of growing livestock population. Of particular interest is how changes in livestock population could alter the environmental health through emissions of greenhouse gases, especially nitrous oxide. Moreover, the quantification of livestock induced nitrous oxide emission with global coverage that characterize consecutive inter-annual variations during historical period is lacking. Thus, in this study, we tried to quantify the magnitude, temporal and spatial variations of livestock-induced nitrous oxide emission during 1860-2014. We include both direct and indirect emission of nitrous oxide from managed soils. We also further analyze the relative contribution of major livestock types on nitrous oxide emission. The results indicated that there was a significant increasing trend of livestock-induced nitrous oxide during 1860-2014. Changes in nitrous oxide emission exhibited highly spatial variability and concentrated in several hotspots during the study period. Less meat consumption is not only good for human health, but also favors for environment-friendly development.

  19. A Survey of Turkish Pre-Service Science Teachers' Attitudes toward the Environment

    ERIC Educational Resources Information Center

    Özsoy, Sibel

    2012-01-01

    Problem Statement: Increasing global population and unrestrained consumption of natural resources has resulted in increasing pollution, poor air and water quality and the extinction of animal and plant species. Today, environmental problems are experienced worldwide and threatening the continuity of human life. For the sake of human beings,…

  20. Human health effects of ozone reduction

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Modification of the stratosphere, such as a reduction in its equilibrium ozone content, could produce direct and indirect effects on human health. The direct hazard to humans would be caused by an increase in the cumulative amount of UV radiation reaching the earth's surface in the range of 285 to 340 nm, encompassing the UV-B or erythemal wavelength region of 280 to 320 nm. Exposing the susceptible human population to an increased total UV dosage of shorter wavelengths could increase skin cancer incidence. Although effects would be delayed by decades, for each 1% decrease in ozone the expected increase in skin cancer incidence would be on the order of 2%.

  1. Diet-Gene Interactions and PUFA Metabolism: A Potential Contributor to Health Disparities and Human Diseases

    PubMed Central

    Chilton, Floyd H.; Murphy, Robert C.; Wilson, Bryan A.; Sergeant, Susan; Ainsworth, Hannah; Seeds, Michael C.; Mathias, Rasika A.

    2014-01-01

    The “modern western” diet (MWD) has increased the onset and progression of chronic human diseases as qualitatively and quantitatively maladaptive dietary components give rise to obesity and destructive gene-diet interactions. There has been a three-fold increase in dietary levels of the omega-6 (n-6) 18 carbon (C18), polyunsaturated fatty acid (PUFA) linoleic acid (LA; 18:2n-6), with the addition of cooking oils and processed foods to the MWD. Intense debate has emerged regarding the impact of this increase on human health. Recent studies have uncovered population-related genetic variation in the LCPUFA biosynthetic pathway (especially within the fatty acid desaturase gene (FADS) cluster) that is associated with levels of circulating and tissue PUFAs and several biomarkers and clinical endpoints of cardiovascular disease (CVD). Importantly, populations of African descent have higher frequencies of variants associated with elevated levels of arachidonic acid (ARA), CVD biomarkers and disease endpoints. Additionally, nutrigenomic interactions between dietary n-6 PUFAs and variants in genes that encode for enzymes that mobilize and metabolize ARA to eicosanoids have been identified. These observations raise important questions of whether gene-PUFA interactions are differentially driving the risk of cardiovascular and other diseases in diverse populations, and contributing to health disparities, especially in African American populations. PMID:24853887

  2. Reconstructing human pancreatic differentiation by mapping specific cell populations during development.

    PubMed

    Ramond, Cyrille; Glaser, Nicolas; Berthault, Claire; Ameri, Jacqueline; Kirkegaard, Jeannette Schlichting; Hansson, Mattias; Honoré, Christian; Semb, Henrik; Scharfmann, Raphaël

    2017-07-21

    Information remains scarce on human development compared to animal models. Here, we reconstructed human fetal pancreatic differentiation using cell surface markers. We demonstrate that at 7weeks of development, the glycoprotein 2 (GP2) marks a multipotent cell population that will differentiate into the acinar, ductal or endocrine lineages. Development towards the acinar lineage is paralleled by an increase in GP2 expression. Conversely, a subset of the GP2 + population undergoes endocrine differentiation by down-regulating GP2 and CD142 and turning on NEUROG3 , a marker of endocrine differentiation. Endocrine maturation progresses by up-regulating SUSD2 and lowering ECAD levels. Finally, in vitro differentiation of pancreatic endocrine cells derived from human pluripotent stem cells mimics key in vivo events. Our work paves the way to extend our understanding of the origin of mature human pancreatic cell types and how such lineage decisions are regulated.

  3. High early life mortality in free-ranging dogs is largely influenced by humans

    PubMed Central

    Paul, Manabi; Sen Majumder, Sreejani; Sau, Shubhra; Nandi, Anjan K.; Bhadra, Anindita

    2016-01-01

    Free-ranging dogs are a ubiquitous part of human habitations in many developing countries, leading a life of scavengers dependent on human wastes for survival. The effective management of free-ranging dogs calls for understanding of their population dynamics. Life expectancy at birth and early life mortality are important factors that shape life-histories of mammals. We carried out a five year-long census based study in seven locations of West Bengal, India, to understand the pattern of population growth and factors affecting early life mortality in free-ranging dogs. We observed high rates of mortality, with only ~19% of the 364 pups from 95 observed litters surviving till the reproductive age; 63% of total mortality being human influenced. While living near people increases resource availability for dogs, it also has deep adverse impacts on their population growth, making the dog-human relationship on streets highly complex. PMID:26804633

  4. Revisiting the Basic Reproductive Number for Malaria and Its Implications for Malaria Control

    PubMed Central

    Smith, David L; McKenzie, F. Ellis; Snow, Robert W; Hay, Simon I

    2007-01-01

    The prospects for the success of malaria control depend, in part, on the basic reproductive number for malaria, R 0. Here, we estimate R 0 in a novel way for 121 African populations, and thereby increase the number of R 0 estimates for malaria by an order of magnitude. The estimates range from around one to more than 3,000. We also consider malaria transmission and control in finite human populations, of size H. We show that classic formulas approximate the expected number of mosquitoes that could trace infection back to one mosquito after one parasite generation, Z 0(H), but they overestimate the expected number of infected humans per infected human, R 0(H). Heterogeneous biting increases R 0 and, as we show, Z 0(H), but we also show that it sometimes reduces R 0(H); those who are bitten most both infect many vectors and absorb infectious bites. The large range of R 0 estimates strongly supports the long-held notion that malaria control presents variable challenges across its transmission spectrum. In populations where R 0 is highest, malaria control will require multiple, integrated methods that target those who are bitten most. Therefore, strategic planning for malaria control should consider R 0, the spatial scale of transmission, human population density, and heterogeneous biting. PMID:17311470

  5. Changing Attitudes towards Ageing and the Aged amongst Psychology Students

    ERIC Educational Resources Information Center

    Fonseca, Antonio; Goncalves, Daniela; Martin, Ignacio

    2009-01-01

    Society is ageing. In Europe, the ageing of the population is a recurrent and discussed theme. The impact of the ageing of the population is varied and transversal in different fields. The increase in the number of elderly people implies an increase in the levels of dependence and, consequently, more sanitary, physical, and human resources. Also,…

  6. Forests and People in the Mid-Atlantic Region

    Treesearch

    Stephanie Fulton; Evan Mercer; M. Patricia Bradley

    2012-01-01

    Human populations in the Mid-Atlantic region over the last 250 years have increased nearly 100-fold, from an estimated few hundred thousand people to over 30 million people (Mercer and Murthy 2000). Increased population growth usually results in the conversion of forestland to nonforest uses, particularly agriculture, pastureland, and urban development. Not only is the...

  7. Research History and Opportunities in the Luquillo Experimental Forest

    Treesearch

    Sandra Brown; Ariel E. Lugo; Susan Silander; Leon Liegel

    1983-01-01

    Tropical forests account for about 50% of the world's total forest area and tropical countries have a total population of about one billion people. Today many of the tropical forests are being subjected to high rates of deforestation because of the increased demand for agricultural land and fuel by the increasing human population. Management of forest areas in...

  8. Local extinction and recolonization, species effective population size, and modern human origins.

    PubMed

    Eller, Elise; Hawks, John; Relethford, John H

    2004-10-01

    A primary objection from a population genetics perspective to a multiregional model of modern human origins is that the model posits a large census size, whereas genetic data suggest a small effective population size. The relationship between census size and effective size is complex, but arguments based on an island model of migration show that if the effective population size reflects the number of breeding individuals and the effects of population subdivision, then an effective population size of 10,000 is inconsistent with the census size of 500,000 to 1,000,000 that has been suggested by archeological evidence. However, these models have ignored the effects of population extinction and recolonization, which increase the expected variance among demes and reduce the inbreeding effective population size. Using models developed for population extinction and recolonization, we show that a large census size consistent with the multiregional model can be reconciled with an effective population size of 10,000, but genetic variation among demes must be high, reflecting low interdeme migration rates and a colonization process that involves a small number of colonists or kin-structured colonization. Ethnographic and archeological evidence is insufficient to determine whether such demographic conditions existed among Pleistocene human populations, and further work needs to be done. More realistic models that incorporate isolation by distance and heterogeneity in extinction rates and effective deme sizes also need to be developed. However, if true, a process of population extinction and recolonization has interesting implications for human demographic history.

  9. Quantifying the Human Impacts on Papua New Guinea Reef Fish Communities across Space and Time.

    PubMed

    Drew, Joshua A; Amatangelo, Kathryn L; Hufbauer, Ruth A

    2015-01-01

    Describing the drivers of species loss and of community change are important goals in both conservation and ecology. However, it is difficult to determine whether exploited species decline due to direct effects of harvesting or due to other environmental perturbations brought about by proximity to human populations. Here we quantify differences in species richness of coral reef fish communities along a human population gradient in Papua New Guinea to understand the relative impacts of fishing and environmental perturbation. Using data from published species lists we categorize the reef fishes as either fished or non-fished based on their body size and reports from the published literature. Species diversity for both fished and non-fished groups decreases as the size of the local human population increases, and this relationship is stronger in species that are fished. Additionally, comparison of modern and museum collections show that modern reef communities have proportionally fewer fished species relative to 19th century ones. Together these findings show that the reef fish communities of Papua New Guinea experience multiple anthropogenic stressors and that even at low human population levels targeted species experience population declines across both time and space.

  10. Evolution and population genetics of exotic and reemerging pathogens: traditional and novel tools and approaches

    Treesearch

    N.J. Grünwald; E.M. Goss

    2011-01-01

    Given human population growth and accelerated global trade, the rate of emergence of exotic plant pathogens is bound to increase. Understanding the processes that lead to the emergence of new pathogens can help manage emerging epidemics. Novel tools for analyzing population genetic variation can be used to infer the evolutionary history of populations or species,...

  11. Climatic and human controls on the late Holocene fire history of northern Israel

    NASA Astrophysics Data System (ADS)

    Quintana Krupinski, N. B.; Nishri, A.; Street, J. H.; Paytan, A.

    2011-12-01

    Long-term fire histories provide insight into the effects of climate, ecology and human influence on fire activity. Fire records can be expanded beyond the period of historical record using accumulation rates of large charcoal particles and soot black carbon (BC) in lacustrine sediments: charcoal accumulation peaks indicate local to regional fire events, while increased deposition of BC may document regional-scale burning. To determine which factors exert the greatest control over changes in fire frequency at different times, this study compares late Holocene fire records from Lake Kinneret (the Sea of Galilee), Israel to local and regional records of climate and human activity. We show that fire frequency decreased during the past 3010 years from 3-4 fire events per 400 years between 3010 - 2620 y.b.p. to 0-2 fire events per 400 years from 750 y.b.p. to present. Human modification of the landscape during periods of high population (e.g. forest clearing, agriculture, settlement expansion and industry) appears to have been the greatest contributor to increased fire activity in the semi-arid southern Levant region during the late Holocene, though aridity may also have contributed to higher fire activity. However, during much of the study period, climate and human activity were interrelated, so while human activity may have been the greater control on fire activity, the effect of climate may have been both direct and indirect (through climate-related changes in population), making it sometimes difficult to distinguish the two controls. Projections of increasing aridification of the region combined with a heavy impact on the landscape from a large modern population suggest that increased fire activity may occur in the region in the near future.

  12. Bats and emerging zoonoses: henipaviruses and SARS.

    PubMed

    Field, H E

    2009-08-01

    Nearly 75% of all emerging infectious diseases (EIDs) that impact or threaten human health are zoonotic. The majority have spilled from wildlife reservoirs, either directly to humans or via domestic animals. The emergence of many can be attributed to predisposing factors such as global travel, trade, agricultural expansion, deforestation/habitat fragmentation, and urbanization; such factors increase the interface and/or the rate of contact between human, domestic animal, and wildlife populations, thereby creating increased opportunities for spillover events to occur. Infectious disease emergence can be regarded as primarily an ecological process. The epidemiological investigation of EIDs associated with wildlife requires a trans-disciplinary approach that includes an understanding of the ecology of the wildlife species, and an understanding of human behaviours that increase risk of exposure. Investigations of the emergence of Nipah virus in Malaysia in 1999 and severe acute respiratory syndrome (SARS) in China in 2003 provide useful case studies. The emergence of Nipah virus was associated with the increased size and density of commercial pig farms and their encroachment into forested areas. The movement of pigs for sale and slaughter in turn led to the rapid spread of infection to southern peninsular Malaysia, where the high-density, largely urban pig populations facilitated transmission to humans. Identifying the factors associated with the emergence of SARS in southern China requires an understanding of the ecology of infection both in the natural reservoir and in secondary market reservoir species. A necessary extension of understanding the ecology of the reservoir is an understanding of the trade, and of the social and cultural context of wildlife consumption. Emerging infectious diseases originating from wildlife populations will continue to threaten public health. Mitigating and managing the risk requires an appreciation of the connectedness between human, livestock and wildlife health, and of the factors and processes that disrupt the balance.

  13. Sink populations in carnivore management: cougar demography and immigration in a hunted population.

    PubMed

    Robinson, Hugh S; Wielgus, Robert B; Cooley, Hilary S; Cooley, Skye W

    2008-06-01

    Carnivores are widely hunted for both sport and population control, especially where they conflict with human interests. It is widely believed that sport hunting is effective in reducing carnivore populations and related human-carnivore conflicts, while maintaining viable populations. However, the way in which carnivore populations respond to harvest can vary greatly depending on their social structure, reproductive strategies, and dispersal patterns. For example, hunted cougar (Puma concolor) populations have shown a great degree of resiliency. Although hunting cougars on a broad geographic scale (> 2000 km2) has reduced densities, hunting of smaller areas (i.e., game management units, < 1000 km2), could conceivably fail because of increased immigration from adjacent source areas. We monitored a heavily hunted population from 2001 to 2006 to test for the effects of hunting at a small scale (< 1000 km2) and to gauge whether population control was achieved (lambda < or = 1.0) or if hunting losses were negated by increased immigration allowing the population to remain stable or increase (lambda > or = 1.0). The observed growth rate of 1.00 was significantly higher than our predicted survival/fecundity growth rates (using a Leslie matrix) of 0.89 (deterministic) and 0.84 (stochastic), with the difference representing an 11-16% annual immigration rate. We observed no decline in density of the total population or the adult population, but a significant decrease in the average age of independent males. We found that the male component of the population was increasing (observed male population growth rate, lambda(OM) = 1.09), masking a decrease in the female component (lambda(OF) = 0.91). Our data support the compensatory immigration sink hypothesis; cougar removal in small game management areas (< 1000 km2) increased immigration and recruitment of younger animals from adjacent areas, resulting in little or no reduction in local cougar densities and a shift in population structure toward younger animals. Hunting in high-quality habitats may create an attractive sink, leading to misinterpretation of population trends and masking population declines in the sink and surrounding source areas.

  14. The potential impacts of 21st century climatic and population changes on human exposure to the virus vector mosquito Aedes aegypti.

    PubMed

    Monaghan, A J; Sampson, K M; Steinhoff, D F; Ernst, K C; Ebi, K L; Jones, B; Hayden, M H

    2018-02-01

    The mosquito Aedes (Ae). aegypti transmits the viruses that cause dengue and chikungunya, two globally-important vector-borne diseases. We investigate how choosing alternate emissions and/or socioeconomic pathways may modulate future human exposure to Ae. aegypti . Occurrence patterns for Ae. aegypti for 2061-2080 are mapped globally using empirically downscaled air temperature and precipitation projections from the Community Earth System Model, for the Representative Concentration Pathway (RCP) 4.5 and 8.5 scenarios. Population growth is quantified using gridded global population projections consistent with two Shared Socioeconomic Pathways (SSPs), SSP3 and SSP5. Change scenarios are compared to a 1950-2000 reference period. A global land area of 56.9 M km 2 is climatically suitable for Ae. aegypti during the reference period, and is projected to increase by 8% (RCP4.5) to 13% (RCP8.5) by 2061-2080. The annual average number of people exposed globally to Ae. aegypti for the reference period is 3794 M, a value projected to statistically significantly increase by 298-460 M (8-12%) by 2061-2080 if only climate change is considered, and by 4805-5084 M (127-134%) for SSP3 and 2232-2483 M (59-65%) for SSP5 considering both climate and population change (lower and upper values of each range represent RCP4.5 and RCP8.5 respectively). Thus, taking the lower-emissions RCP4.5 pathway instead of RCP8.5 may mitigate future human exposure to Ae. aegypti globally, but the effect of population growth on exposure will likely be larger. Regionally, Australia, Europe and North America are projected to have the largest percentage increases in human exposure to Ae. aegypti considering only climate change.

  15. The Human Impact of Earthquakes: a Historical Review of Events 1980-2009 and Systematic Literature Review

    PubMed Central

    Doocy, Shannon; Daniels, Amy; Packer, Catherine; Dick, Anna; Kirsch, Thomas D.

    2013-01-01

    Introduction. Population growth and increasing urbanization in earthquake-prone areas suggest that earthquake impacts on human populations will increase in the coming decades. Recent large earthquakes affecting large populations in Japan, Haiti, Chile and New Zealand are evidence of this trend and also illustrate significant variations in outcomes such damage and mortality levels. The objectives of this review were to describe the impact of earthquakes on human populations in terms of mortality, injury and displacement and, to the extent possible, identify risk factors associated with these outcomes. This is one of five reviews on the human impact of natural disasters. Methods. Data on the impact of earthquakes were compiled using two methods, a historical review from 1980 to mid 2009 of earthquake events from multiple databases and a systematic literature review of publications, ending in October 2012. Analysis included descriptive statistics and bivariate tests for associations between earthquake mortality and characteristics using STATA 11. Findings. From 1980 through 2009, there were a total of 372,634 deaths (range 314,634-412,599), 995,219 injuries (range: 845,345-1,145,093), and more than 61 million people affected by earthquakes, and mortality was greatest in Asia. Inconsistent reporting across data sources suggests that the numbers injured and affected are likely underestimates. Findings from a systematic review of the literature indicate that the primary cause of earthquake-related death was trauma due to building collapse and, the very young and the elderly were at increased mortality risk, while gender was not consistently associated with mortality risk. Conclusions. Strategies to mitigate the impact of future earthquakes should include improvements to the built environment and a focus on populations most vulnerable to mortality and injury. PMID:23857161

  16. Holocene fluctuations in human population demonstrate repeated links to food production and climate.

    PubMed

    Bevan, Andrew; Colledge, Sue; Fuller, Dorian; Fyfe, Ralph; Shennan, Stephen; Stevens, Chris

    2017-12-05

    We consider the long-term relationship between human demography, food production, and Holocene climate via an archaeological radiocarbon date series of unprecedented sampling density and detail. There is striking consistency in the inferred human population dynamics across different regions of Britain and Ireland during the middle and later Holocene. Major cross-regional population downturns in population coincide with episodes of more abrupt change in North Atlantic climate and witness societal responses in food procurement as visible in directly dated plants and animals, often with moves toward hardier cereals, increased pastoralism, and/or gathered resources. For the Neolithic, this evidence questions existing models of wholly endogenous demographic boom-bust. For the wider Holocene, it demonstrates that climate-related disruptions have been quasi-periodic drivers of societal and subsistence change. Copyright © 2017 the Author(s). Published by PNAS.

  17. Health, human rights, and the conduct of clinical research within oppressed populations

    PubMed Central

    Mills, Edward J; Singh, Sonal

    2007-01-01

    Background Clinical trials evaluating interventions for infectious diseases require enrolling participants that are vulnerable to infection. As clinical trials are conducted in increasingly vulnerable populations, issues of protection of these populations become challenging. In settings where populations are forseeably oppressed, the conduct of research requires considerations that go beyond common ethical concerns and into issues of international human rights law. Discussion Using examples of HIV prevention trials in Thailand, hepatitis-E prevention trials in Nepal and malaria therapeutic trials in Burma (Myanmar), we address the inadequacies of current ethical guidelines when conducting research within oppressed populations. We review existing legislature in the United States and United Kingdom that may be used against foreign investigators if trial hardships exist. We conclude by making considerations for research conducted within oppressed populations. PMID:17996056

  18. An Upper Limit on the Functional Fraction of the Human Genome.

    PubMed

    Graur, Dan

    2017-07-01

    For the human population to maintain a constant size from generation to generation, an increase in fertility must compensate for the reduction in the mean fitness of the population caused, among others, by deleterious mutations. The required increase in fertility due to this mutational load depends on the number of sites in the genome that are functional, the mutation rate, and the fraction of deleterious mutations among all mutations in functional regions. These dependencies and the fact that there exists a maximum tolerable replacement level fertility can be used to put an upper limit on the fraction of the human genome that can be functional. Mutational load considerations lead to the conclusion that the functional fraction within the human genome cannot exceed 25%, and is probably considerably lower. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  19. Human-induced evolution caused by unnatural selection through harvest of wild animals

    PubMed Central

    Allendorf, Fred W.; Hard, Jeffrey J.

    2009-01-01

    Human harvest of phenotypically desirable animals from wild populations imposes selection that can reduce the frequencies of those desirable phenotypes. Hunting and fishing contrast with agricultural and aquacultural practices in which the most desirable animals are typically bred with the specific goal of increasing the frequency of desirable phenotypes. We consider the potential effects of harvest on the genetics and sustainability of wild populations. We also consider how harvesting could affect the mating system and thereby modify sexual selection in a way that might affect recruitment. Determining whether phenotypic changes in harvested populations are due to evolution, rather than phenotypic plasticity or environmental variation, has been problematic. Nevertheless, it is likely that some undesirable changes observed over time in exploited populations (e.g., reduced body size, earlier sexual maturity, reduced antler size, etc.) are due to selection against desirable phenotypes—a process we call “unnatural” selection. Evolution brought about by human harvest might greatly increase the time required for over-harvested populations to recover once harvest is curtailed because harvesting often creates strong selection differentials, whereas curtailing harvest will often result in less intense selection in the opposing direction. We strongly encourage those responsible for managing harvested wild populations to take into account possible selective effects of harvest management and to implement monitoring programs to detect exploitation-induced selection before it seriously impacts viability. PMID:19528656

  20. Increased human occupation and agricultural development accelerates the population contraction of an estuarine delphinid.

    PubMed

    Lin, Wenzhi; Karczmarski, Leszek; Xia, Jia; Zhang, Xiyang; Yu, Xinjian; Wu, Yuping

    2016-10-19

    Over the past few thousand years, human development and population expansion in southern China have led to local extirpation and population contraction of many terrestrial animals. At what extent this early human-induced environmental change has also affected coastal marine species remains poorly known. We investigated the demographic history of the Indo-Pacific humpback dolphin (Sousa chinensis) in the Pearl River Delta (PRD); an obligatory inshore species known for its susceptibility to anthropogenic impacts in one of China's most developed coastal regions. Although the deltaic evolution of PRD has been influenced by climate since the Holocene, ~74% reduction of the dolphin's effective population size occurred within the last 2000 years, consistent with ~61% habitat contraction during this period. This considerable and recent population contraction may have been due to land use practices and deforestation in the upper/middle Pearl River region, all leading to increasing sedimentation rate in the estuarine area. As anthropogenic impacts within the drainage of Pearl River affected a vast area, coastal dolphins and large terrestrial mammals in southern China may share a similar demographic history, whilst the demographic and biogeographic history of the PRD humpback dolphins may be symptomatic of similar processes that this species may have undergone elsewhere in the region.

  1. Greater than the sum of its parts? Modelling population contact and interaction of cultural repertoires

    PubMed Central

    Kolodny, Oren; Feldman, Marcus W.

    2017-01-01

    Evidence for interactions between populations plays a prominent role in the reconstruction of historical and prehistoric human dynamics; these interactions are usually interpreted to reflect cultural practices or demographic processes. The sharp increase in long-distance transportation of lithic material between the Middle and Upper Palaeolithic, for example, is seen as a manifestation of the cultural revolution that defined the transition between these epochs. Here, we propose that population interaction is not only a reflection of cultural change but also a potential driver of it. We explore the possible effects of inter-population migration on cultural evolution when migrating individuals possess core technological knowledge from their original population. Using a computational framework of cultural evolution that incorporates realistic aspects of human innovation processes, we show that migration can lead to a range of outcomes, including punctuated but transient increases in cultural complexity, an increase of cultural complexity to an elevated steady state and the emergence of a positive feedback loop that drives ongoing acceleration in cultural accumulation. Our findings suggest that population contact may have played a crucial role in the evolution of hominin cultures and propose explanations for observations of Palaeolithic cultural change whose interpretations have been hotly debated. PMID:28468920

  2. Population Growth, Energy Use, and Pollution: Understanding the Driving Forces of Global Change. Hands-On! Developing Active Learning Modules on the Human Dimensions of Global Change.

    ERIC Educational Resources Information Center

    Kuby, Michael

    Since the beginning of the scientific revolution in the 1700s, the absolute scale of the human economy has increased many times over, and, with it, the impact on the natural environment. This learning module's activities introduce the student to linkages among population growth, energy use, level of economic and technological development and their…

  3. Climate change, human health, and epidemiological transition

    PubMed Central

    Barrett, Bruce; Charles, Joel W.; Temte, Jonathan L.

    2015-01-01

    The health of populations depends on the availability of clean air, water, food, and sanitation, exposure to pathogens, toxins and environmental hazards, and numerous genetic, behavioral and social factors. For many thousands of years, human life expectancy was low, and population growth was slow. The development of technology-based civilizations facilitated what Abdel Omran called “epidemiological transition,” with increasing life expectancy and rapid population growth. To a large extent, the spectacular growth of human populations during the past two centuries was made possible by the energy extracted from fossil fuels. We have now learned, however, that greenhouse gases from fossil fuel combustion are warming the planet's surface, causing changes in oceanic and atmospheric systems, and disrupting weather and hydrological patterns. Climate change poses unprecedented threats to human health by impacts on food and water security, heat waves and droughts, violent storms, infectious disease, and rising sea levels. Whether or not humanity can reduce greenhouse gas emissions quickly enough to slow climate change to a rate that will allow societies to successfully adapt is not yet known. This essay reviews the current state of relevant knowledge, and points in a few directions that those interested in human health may wish to consider. PMID:25434735

  4. Estimation of a genetically viable population for multigenerational interstellar voyaging: Review and data for project Hyperion

    NASA Astrophysics Data System (ADS)

    Smith, Cameron M.

    2014-04-01

    Designing interstellar starships for human migration to exoplanets requires establishing the starship population, which factors into many variables including closed-ecosystem design, architecture, mass and propulsion. I review the central issues of population genetics (effects of mutation, migration, selection and drift) for human populations on such voyages, specifically referencing a roughly 5-generation (c. 150-year) voyage currently in the realm of thought among Icarus Interstellar's Project Hyperion research group. I present several formulae as well as concrete numbers that can be used to help determine populations that could survive such journeys in good health. I find that previously proposed such populations, on the order of a few hundred individuals, are significantly too low to consider based on current understanding of vertebrate (including human) genetics and population dynamics. Population genetics theory, calculations and computer modeling determine that a properly screened and age- and sex-structured total founding population (Nc) of anywhere from roughly 14,000 to 44,000 people would be sufficient to survive such journeys in good health. A safe and well-considered Nc figure is 40,000, an Interstellar Migrant Population (IMP) composed of an Effective Population [Ne] of 23,400 reproductive males and females, the rest being pre- or post-reproductive individuals. This number would maintain good health over five generations despite (a) increased inbreeding resulting from a relatively small human population, (b) depressed genetic diversity due to the founder effect, (c) demographic change through time and (d) expectation of at least one severe population catastrophe over the 5-generation voyage.

  5. Human Occupancy as a Source of Indoor Airborne Bacteria

    PubMed Central

    Hospodsky, Denina; Qian, Jing; Nazaroff, William W.; Yamamoto, Naomichi; Bibby, Kyle; Rismani-Yazdi, Hamid; Peccia, Jordan

    2012-01-01

    Exposure to specific airborne bacteria indoors is linked to infectious and noninfectious adverse health outcomes. However, the sources and origins of bacteria suspended in indoor air are not well understood. This study presents evidence for elevated concentrations of indoor airborne bacteria due to human occupancy, and investigates the sources of these bacteria. Samples were collected in a university classroom while occupied and when vacant. The total particle mass concentration, bacterial genome concentration, and bacterial phylogenetic populations were characterized in indoor, outdoor, and ventilation duct supply air, as well as in the dust of ventilation system filters and in floor dust. Occupancy increased the total aerosol mass and bacterial genome concentration in indoor air PM10 and PM2.5 size fractions, with an increase of nearly two orders of magnitude in airborne bacterial genome concentration in PM10. On a per mass basis, floor dust was enriched in bacterial genomes compared to airborne particles. Quantitative comparisons between bacterial populations in indoor air and potential sources suggest that resuspended floor dust is an important contributor to bacterial aerosol populations during occupancy. Experiments that controlled for resuspension from the floor implies that direct human shedding may also significantly impact the concentration of indoor airborne particles. The high content of bacteria specific to the skin, nostrils, and hair of humans found in indoor air and in floor dust indicates that floors are an important reservoir of human-associated bacteria, and that the direct particle shedding of desquamated skin cells and their subsequent resuspension strongly influenced the airborne bacteria population structure in this human-occupied environment. Inhalation exposure to microbes shed by other current or previous human occupants may occur in communal indoor environments. PMID:22529946

  6. Landscape requirements of a primate population in a human-dominated environment

    PubMed Central

    2012-01-01

    Introduction As urban and rural land development become widespread features of the global landscape so an understanding of the landscape requirements of displaced and isolated wildlife species becomes increasingly important for conservation planning. In the Cape Peninsula, South Africa, rapid human population growth, and the associated urban and rural land transformation, threatens the sustainability of the local chacma baboon population. Here we analyse spatial data collected from nine of the 12 extant troops to determine their population-level landscape requirements. We use hurdle models to ascertain the key landscape features influencing baboon occurrence and abundance patterns on two hierarchical spatial scales. Results Both spatial scales produced similar results that were ecologically reliable and interpretable. The models indicated that baboons were more likely to occur, and be more abundant, at low altitudes, on steep slopes and in human-modified habitats. The combination of these landscape variables provides baboons with access to the best quality natural and anthropogenic food sources in close proximity to one another and suitable sleeping sites. Surface water did not emerge as an influential landscape feature presumably as the area is not water stressed. Conclusions The model results indicate that land development in the Cape Peninsula has pushed baboons into increasingly marginal natural habitat while simultaneously providing them with predictable and easily accessible food sources in human-modified habitats. The resultant spatial competition between humans and baboons explains the high levels of human-baboon conflict and further erosion of the remaining land fragments is predicted to exacerbate competition. This study demonstrates how the quantification of animal landscape requirements can provide a mechanism for identifying priority conservation areas at the human-wildlife interface. PMID:22269662

  7. Food provisioning increases the risk of injury in a long-lived marine top predator.

    PubMed

    Christiansen, Fredrik; McHugh, Katherine A; Bejder, Lars; Siegal, Eilidh M; Lusseau, David; McCabe, Elizabeth Berens; Lovewell, Gretchen; Wells, Randall S

    2016-12-01

    Food provisioning of wildlife is a major concern for management and conservation agencies worldwide because it encourages unnatural behaviours in wild animals and increases each individual's risk for injury and death. Here we investigate the contributing factors and potential fitness consequences of a recent increase in the frequency of human interactions with common bottlenose dolphins ( Tursiops truncatus ) in Sarasota Bay, Florida. A rising proportion of the local long-term resident dolphin community is becoming conditioned to human interactions through direct and indirect food provisioning. We investigate variables that are affecting conditioning and if the presence of human-induced injuries is higher for conditioned versus unconditioned dolphins. Using the most comprehensive long-term dataset available for a free-ranging bottlenose dolphin population (more than 45 years; more than 32 000 dolphin group sightings; more than 1100 individuals), we found that the association with already conditioned animals strongly affected the probability of dolphins becoming conditioned to human interactions, confirming earlier findings that conditioning is partly a learned behaviour. More importantly, we found that conditioned dolphins were more likely to be injured by human interactions when compared with unconditioned animals. This is alarming, as conditioning could lead to a decrease in survival, which could have population-level consequences. We did not find a significant relationship between human exposure or natural prey availability and the probability of dolphins becoming conditioned. This could be due to low sample size or insufficient spatio-temporal resolution in the available data. Our findings show that wildlife provisioning may lead to a decrease in survival, which could ultimately affect population dynamics.

  8. Food provisioning increases the risk of injury in a long-lived marine top predator

    PubMed Central

    McHugh, Katherine A.; Siegal, Eilidh M.; Lusseau, David; McCabe, Elizabeth Berens; Lovewell, Gretchen; Wells, Randall S.

    2016-01-01

    Food provisioning of wildlife is a major concern for management and conservation agencies worldwide because it encourages unnatural behaviours in wild animals and increases each individual's risk for injury and death. Here we investigate the contributing factors and potential fitness consequences of a recent increase in the frequency of human interactions with common bottlenose dolphins (Tursiops truncatus) in Sarasota Bay, Florida. A rising proportion of the local long-term resident dolphin community is becoming conditioned to human interactions through direct and indirect food provisioning. We investigate variables that are affecting conditioning and if the presence of human-induced injuries is higher for conditioned versus unconditioned dolphins. Using the most comprehensive long-term dataset available for a free-ranging bottlenose dolphin population (more than 45 years; more than 32 000 dolphin group sightings; more than 1100 individuals), we found that the association with already conditioned animals strongly affected the probability of dolphins becoming conditioned to human interactions, confirming earlier findings that conditioning is partly a learned behaviour. More importantly, we found that conditioned dolphins were more likely to be injured by human interactions when compared with unconditioned animals. This is alarming, as conditioning could lead to a decrease in survival, which could have population-level consequences. We did not find a significant relationship between human exposure or natural prey availability and the probability of dolphins becoming conditioned. This could be due to low sample size or insufficient spatio-temporal resolution in the available data. Our findings show that wildlife provisioning may lead to a decrease in survival, which could ultimately affect population dynamics. PMID:28083101

  9. Evolutionary Genomics of Wheat

    USDA-ARS?s Scientific Manuscript database

    Wheat is the world’s largest and most important food crop for direct human consumption, therefore, continued wheat improvement is paramount for feeding an ever-increasing human population. Wheat improvement is tightly associated with the characterization and understanding of wheat evolution and gene...

  10. Has Rift Valley fever virus evolved with increasing severity in human populations in East Africa?

    PubMed Central

    Baba, Marycelin; Masiga, Daniel K; Sang, Rosemary; Villinger, Jandouwe

    2016-01-01

    Rift Valley fever (RVF) outbreaks have occurred across eastern Africa from 1912 to 2010 approximately every 4–15 years, most of which have not been accompanied by significant epidemics in human populations. However, human epidemics during RVF outbreaks in eastern Africa have involved 478 deaths in 1998, 1107 reported cases with 350 deaths from 2006 to 2007 and 1174 cases with 241 deaths in 2008. We review the history of RVF outbreaks in eastern Africa to identify the epidemiological factors that could have influenced its increasing severity in humans. Diverse ecological factors influence outbreak frequency, whereas virus evolution has a greater impact on its virulence in hosts. Several factors could have influenced the lack of information on RVF in humans during earlier outbreaks, but the explosive nature of human RVF epidemics in recent years mirrors the evolutionary trend of the virus. Comparisons between isolates from different outbreaks have revealed an accumulation of genetic mutations and genomic reassortments that have diversified RVF virus genomes over several decades. The threat to humans posed by the diversified RVF virus strains increases the potential public health and socioeconomic impacts of future outbreaks. Understanding the shifting RVF epidemiology as determined by its evolution is key to developing new strategies for outbreak mitigation and prevention of future human RVF casualties. PMID:27329846

  11. Cougar response to a gradient of human development

    DOE PAGES

    Maletzke, Benjamin; Kertson, Brian; Swanson, Mark; ...

    2017-07-07

    Human populations continue to increase and transform Earth's ecosystems. For large carnivores, human development reduces habitat abundance, alters predator–prey dynamics, and increases the risk of mortality, which may threaten the viability of many populations. To investigate how the cougar ( Puma concolor) responds to a gradient of human development in four areas in Washington, USA, we used utilization distributions, county tax parcel data, Weibull modeling analysis, and multiple comparison techniques. Cougars used wildland areas the majority of the time (79% ± 2%, n = 112 cougars), with use decreasing as housing densities increased. When present in human-developed areas in easternmore » Washington, 99% of the habitat that cougars used had housing densities ≤76.5 residences/km 2, which was <846.0 residences/km 2 observed in western Washington ( P < 0.01). Cougars used areas in western Washington with greater housing density likely because of the clustered nature of housing developments, the connectivity with greenbelts and forested corridors, and security cover of dense maritime vegetation. Our findings suggest a consistent, albeit nuanced response by cougars to human development that may be used by wildlife managers, landscape planners, and environmental educators to guide and enhance their efforts to minimize the impacts of human development on cougars and reduce the potential for conflicts with people. In conclusion, our model may also provide guidance for thresholds of human development for other adaptable large carnivores.« less

  12. Cougar response to a gradient of human development

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maletzke, Benjamin; Kertson, Brian; Swanson, Mark

    Human populations continue to increase and transform Earth's ecosystems. For large carnivores, human development reduces habitat abundance, alters predator–prey dynamics, and increases the risk of mortality, which may threaten the viability of many populations. To investigate how the cougar ( Puma concolor) responds to a gradient of human development in four areas in Washington, USA, we used utilization distributions, county tax parcel data, Weibull modeling analysis, and multiple comparison techniques. Cougars used wildland areas the majority of the time (79% ± 2%, n = 112 cougars), with use decreasing as housing densities increased. When present in human-developed areas in easternmore » Washington, 99% of the habitat that cougars used had housing densities ≤76.5 residences/km 2, which was <846.0 residences/km 2 observed in western Washington ( P < 0.01). Cougars used areas in western Washington with greater housing density likely because of the clustered nature of housing developments, the connectivity with greenbelts and forested corridors, and security cover of dense maritime vegetation. Our findings suggest a consistent, albeit nuanced response by cougars to human development that may be used by wildlife managers, landscape planners, and environmental educators to guide and enhance their efforts to minimize the impacts of human development on cougars and reduce the potential for conflicts with people. In conclusion, our model may also provide guidance for thresholds of human development for other adaptable large carnivores.« less

  13. Sedimentary archives of fire, vegetation history, and human impacts during the late Holocene in the eastern lowland of Taiwan

    NASA Astrophysics Data System (ADS)

    Wang, Liang-Chi

    2017-04-01

    The Hualien Plain is one of the richest prehistoric sites in eastern Taiwan, and the reconstruction of late Holocene environment on the basis of the lacustrine sediments near Hualien Plain can benefit to the understandings of human-climate-environment interactions in past. The multi-decadal records of vegetation history, agriculture evidences and fire events in Liyu Lake of eastern Taiwan were reconstructed by using palynological and charcoal analysis of lake sediments. A 2.8 m sediment core covering a time period from 2,680 cal BP to the present was used to investigate the alterations in the landscape with respect to human activities and climate change. During 2680-2410 cal yr BP, frequent burning and high preservation of cultivated Poaceae pollen indicated the early cultivation during the late Neolithic period. There followed a warm climate during 2,410-1,510 cal yr BP, and the increase of lowland forest pollen showed a period of forest recovery as a consequence of reducing human activity. Following a phase of recolonization of prehistory human during 1510-560 cal yr BP, a slightly increasing trend of cultivated Poacease indicated the human activities, but the human population was low. The last 560 years record showed an intense trend of deforestation and cultivation which may correlate to a rapid increase in the human population in this area.

  14. Human Behavioral Contributions to Climate Change: Psychological and Contextual Drivers

    ERIC Educational Resources Information Center

    Swim, Janet K.; Clayton, Susan; Howard, George S.

    2011-01-01

    We are facing rapid changes in the global climate, and these changes are attributable to human behavior. Humans produce this global impact through our use of natural resources, multiplied by the vast increase in population seen in the past 50 to 100 years. Our goal in this article is to examine the underlying psychosocial causes of human impact,…

  15. Distance from sub-Saharan Africa predicts mutational load in diverse human genomes.

    PubMed

    Henn, Brenna M; Botigué, Laura R; Peischl, Stephan; Dupanloup, Isabelle; Lipatov, Mikhail; Maples, Brian K; Martin, Alicia R; Musharoff, Shaila; Cann, Howard; Snyder, Michael P; Excoffier, Laurent; Kidd, Jeffrey M; Bustamante, Carlos D

    2016-01-26

    The Out-of-Africa (OOA) dispersal ∼ 50,000 y ago is characterized by a series of founder events as modern humans expanded into multiple continents. Population genetics theory predicts an increase of mutational load in populations undergoing serial founder effects during range expansions. To test this hypothesis, we have sequenced full genomes and high-coverage exomes from seven geographically divergent human populations from Namibia, Congo, Algeria, Pakistan, Cambodia, Siberia, and Mexico. We find that individual genomes vary modestly in the overall number of predicted deleterious alleles. We show via spatially explicit simulations that the observed distribution of deleterious allele frequencies is consistent with the OOA dispersal, particularly under a model where deleterious mutations are recessive. We conclude that there is a strong signal of purifying selection at conserved genomic positions within Africa, but that many predicted deleterious mutations have evolved as if they were neutral during the expansion out of Africa. Under a model where selection is inversely related to dominance, we show that OOA populations are likely to have a higher mutation load due to increased allele frequencies of nearly neutral variants that are recessive or partially recessive.

  16. Long-Term Trends and Role of Climate in the Population Dynamics of Eurasian Reindeer

    PubMed Central

    Horstkotte, Tim; Kaarlejärvi, Elina; Sévêque, Anthony; Stammler, Florian; Olofsson, Johan; Forbes, Bruce C.; Moen, Jon

    2016-01-01

    Temperature is increasing in Arctic and sub-Arctic regions at a higher rate than anywhere else in the world. The frequency and nature of precipitation events are also predicted to change in the future. These changes in climate are expected, together with increasing human pressures, to have significant impacts on Arctic and sub-Arctic species and ecosystems. Due to the key role that reindeer play in those ecosystems, it is essential to understand how climate will affect the region’s most important species. Our study assesses the role of climate on the dynamics of fourteen Eurasian reindeer (Rangifer tarandus) populations, using for the first time data on reindeer abundance collected over a 70-year period, including both wild and semi-domesticated reindeer, and covering more than half of the species’ total range. We analyzed trends in population dynamics, investigated synchrony among population growth rates, and assessed the effects of climate on population growth rates. Trends in the population dynamics were remarkably heterogeneous. Synchrony was apparent only among some populations and was not correlated with distance among population ranges. Proxies of climate variability mostly failed to explain population growth rates and synchrony. For both wild and semi-domesticated populations, local weather, biotic pressures, loss of habitat and human disturbances appear to have been more important drivers of reindeer population dynamics than climate. In semi-domesticated populations, management strategies may have masked the effects of climate. Conservation efforts should aim to mitigate human disturbances, which could exacerbate the potentially negative effects of climate change on reindeer populations in the future. Special protection and support should be granted to those semi-domesticated populations that suffered the most because of the collapse of the Soviet Union, in order to protect the livelihood of indigenous peoples that depend on the species, and the multi-faceted role that reindeer exert in Arctic ecosystems. PMID:27362499

  17. Long-Term Trends and Role of Climate in the Population Dynamics of Eurasian Reindeer.

    PubMed

    Uboni, Alessia; Horstkotte, Tim; Kaarlejärvi, Elina; Sévêque, Anthony; Stammler, Florian; Olofsson, Johan; Forbes, Bruce C; Moen, Jon

    2016-01-01

    Temperature is increasing in Arctic and sub-Arctic regions at a higher rate than anywhere else in the world. The frequency and nature of precipitation events are also predicted to change in the future. These changes in climate are expected, together with increasing human pressures, to have significant impacts on Arctic and sub-Arctic species and ecosystems. Due to the key role that reindeer play in those ecosystems, it is essential to understand how climate will affect the region's most important species. Our study assesses the role of climate on the dynamics of fourteen Eurasian reindeer (Rangifer tarandus) populations, using for the first time data on reindeer abundance collected over a 70-year period, including both wild and semi-domesticated reindeer, and covering more than half of the species' total range. We analyzed trends in population dynamics, investigated synchrony among population growth rates, and assessed the effects of climate on population growth rates. Trends in the population dynamics were remarkably heterogeneous. Synchrony was apparent only among some populations and was not correlated with distance among population ranges. Proxies of climate variability mostly failed to explain population growth rates and synchrony. For both wild and semi-domesticated populations, local weather, biotic pressures, loss of habitat and human disturbances appear to have been more important drivers of reindeer population dynamics than climate. In semi-domesticated populations, management strategies may have masked the effects of climate. Conservation efforts should aim to mitigate human disturbances, which could exacerbate the potentially negative effects of climate change on reindeer populations in the future. Special protection and support should be granted to those semi-domesticated populations that suffered the most because of the collapse of the Soviet Union, in order to protect the livelihood of indigenous peoples that depend on the species, and the multi-faceted role that reindeer exert in Arctic ecosystems.

  18. Conservation genetics of managed ungulate populations

    USGS Publications Warehouse

    Scribner, Kim T.

    1993-01-01

    Natural populations of many species are increasingly impacted by human activities. Perturbations are particularly pronunced for large ungulates due in part to sport and commercial harvest, to reductions and fragmentation of native habitat, and as the result of reintroductions. These perturbations affect population size, sex and age composition, and population breeding structure, and as a consequence affect the levels and partitioning of genetic variation. Three case histories highlighting long-term ecological genetic research on mule deer Odocoileus hemionus (Rafinesque, 1817), white-tailed deer O. virginianus (Zimmermann, 1780), and Alpine ibex Capra i. ibex Linnaeus, 1758 are presented. Joint examinations of population ecological and genetic data from several populations of each species reveal: (1) that populations are not in genetic equilibrium, but that allele frequencies and heterozygosity change dramatically over time and among cohorts produced in successive years, (2) populations are genetically structured over short and large geographic distances reflecting local breeding structure and patterns of gene flow, respectively; however, this structure is quite dynamic over time, due in part to population exploitation, and (3) restocking programs are often undertaken with small numbers of founding individuals resulting in dramatic declines in levels of genetic variability and increasing levels of genetic differentiation among populations due to genetic drift. Genetic characteristics have and will continue to provide valuable indirect sources of information relating enviromental and human perturbations to changes in population processes.

  19. Demographic history and rare allele sharing among human populations.

    PubMed

    Gravel, Simon; Henn, Brenna M; Gutenkunst, Ryan N; Indap, Amit R; Marth, Gabor T; Clark, Andrew G; Yu, Fuli; Gibbs, Richard A; Bustamante, Carlos D

    2011-07-19

    High-throughput sequencing technology enables population-level surveys of human genomic variation. Here, we examine the joint allele frequency distributions across continental human populations and present an approach for combining complementary aspects of whole-genome, low-coverage data and targeted high-coverage data. We apply this approach to data generated by the pilot phase of the Thousand Genomes Project, including whole-genome 2-4× coverage data for 179 samples from HapMap European, Asian, and African panels as well as high-coverage target sequencing of the exons of 800 genes from 697 individuals in seven populations. We use the site frequency spectra obtained from these data to infer demographic parameters for an Out-of-Africa model for populations of African, European, and Asian descent and to predict, by a jackknife-based approach, the amount of genetic diversity that will be discovered as sample sizes are increased. We predict that the number of discovered nonsynonymous coding variants will reach 100,000 in each population after ∼1,000 sequenced chromosomes per population, whereas ∼2,500 chromosomes will be needed for the same number of synonymous variants. Beyond this point, the number of segregating sites in the European and Asian panel populations is expected to overcome that of the African panel because of faster recent population growth. Overall, we find that the majority of human genomic variable sites are rare and exhibit little sharing among diverged populations. Our results emphasize that replication of disease association for specific rare genetic variants across diverged populations must overcome both reduced statistical power because of rarity and higher population divergence.

  20. Demographic history and rare allele sharing among human populations

    PubMed Central

    Gravel, Simon; Henn, Brenna M.; Gutenkunst, Ryan N.; Indap, Amit R.; Marth, Gabor T.; Clark, Andrew G.; Yu, Fuli; Gibbs, Richard A.; Bustamante, Carlos D.; Altshuler, David L.; Durbin, Richard M.; Abecasis, Gonçalo R.; Bentley, David R.; Chakravarti, Aravinda; Clark, Andrew G.; Collins, Francis S.; De La Vega, Francisco M.; Donnelly, Peter; Egholm, Michael; Flicek, Paul; Gabriel, Stacey B.; Gibbs, Richard A.; Knoppers, Bartha M.; Lander, Eric S.; Lehrach, Hans; Mardis, Elaine R.; McVean, Gil A.; Nickerson, Debbie A.; Peltonen, Leena; Schafer, Alan J.; Sherry, Stephen T.; Wang, Jun; Wilson, Richard K.; Gibbs, Richard A.; Deiros, David; Metzker, Mike; Muzny, Donna; Reid, Jeff; Wheeler, David; Wang, Jun; Li, Jingxiang; Jian, Min; Li, Guoqing; Li, Ruiqiang; Liang, Huiqing; Tian, Geng; Wang, Bo; Wang, Jian; Wang, Wei; Yang, Huanming; Zhang, Xiuqing; Zheng, Huisong; Lander, Eric S.; Altshuler, David L.; Ambrogio, Lauren; Bloom, Toby; Cibulskis, Kristian; Fennell, Tim J.; Gabriel, Stacey B.; Jaffe, David B.; Shefler, Erica; Sougnez, Carrie L.; Bentley, David R.; Gormley, Niall; Humphray, Sean; Kingsbury, Zoya; Koko-Gonzales, Paula; Stone, Jennifer; McKernan, Kevin J.; Costa, Gina L.; Ichikawa, Jeffry K.; Lee, Clarence C.; Sudbrak, Ralf; Lehrach, Hans; Borodina, Tatiana A.; Dahl, Andreas; Davydov, Alexey N.; Marquardt, Peter; Mertes, Florian; Nietfeld, Wilfiried; Rosenstiel, Philip; Schreiber, Stefan; Soldatov, Aleksey V.; Timmermann, Bernd; Tolzmann, Marius; Egholm, Michael; Affourtit, Jason; Ashworth, Dana; Attiya, Said; Bachorski, Melissa; Buglione, Eli; Burke, Adam; Caprio, Amanda; Celone, Christopher; Clark, Shauna; Conners, David; Desany, Brian; Gu, Lisa; Guccione, Lorri; Kao, Kalvin; Kebbel, Andrew; Knowlton, Jennifer; Labrecque, Matthew; McDade, Louise; Mealmaker, Craig; Minderman, Melissa; Nawrocki, Anne; Niazi, Faheem; Pareja, Kristen; Ramenani, Ravi; Riches, David; Song, Wanmin; Turcotte, Cynthia; Wang, Shally; Mardis, Elaine R.; Wilson, Richard K.; Dooling, David; Fulton, Lucinda; Fulton, Robert; Weinstock, George; Durbin, Richard M.; Burton, John; Carter, David M.; Churcher, Carol; Coffey, Alison; Cox, Anthony; Palotie, Aarno; Quail, Michael; Skelly, Tom; Stalker, James; Swerdlow, Harold P.; Turner, Daniel; De Witte, Anniek; Giles, Shane; Gibbs, Richard A.; Wheeler, David; Bainbridge, Matthew; Challis, Danny; Sabo, Aniko; Yu, Fuli; Yu, Jin; Wang, Jun; Fang, Xiaodong; Guo, Xiaosen; Li, Ruiqiang; Li, Yingrui; Luo, Ruibang; Tai, Shuaishuai; Wu, Honglong; Zheng, Hancheng; Zheng, Xiaole; Zhou, Yan; Li, Guoqing; Wang, Jian; Yang, Huanming; Marth, Gabor T.; Garrison, Erik P.; Huang, Weichun; Indap, Amit; Kural, Deniz; Lee, Wan-Ping; Leong, Wen Fung; Quinlan, Aaron R.; Stewart, Chip; Stromberg, Michael P.; Ward, Alistair N.; Wu, Jiantao; Lee, Charles; Mills, Ryan E.; Shi, Xinghua; Daly, Mark J.; DePristo, Mark A.; Altshuler, David L.; Ball, Aaron D.; Banks, Eric; Bloom, Toby; Browning, Brian L.; Cibulskis, Kristian; Fennell, Tim J.; Garimella, Kiran V.; Grossman, Sharon R.; Handsaker, Robert E.; Hanna, Matt; Hartl, Chris; Jaffe, David B.; Kernytsky, Andrew M.; Korn, Joshua M.; Li, Heng; Maguire, Jared R.; McCarroll, Steven A.; McKenna, Aaron; Nemesh, James C.; Philippakis, Anthony A.; Poplin, Ryan E.; Price, Alkes; Rivas, Manuel A.; Sabeti, Pardis C.; Schaffner, Stephen F.; Shefler, Erica; Shlyakhter, Ilya A.; Cooper, David N.; Ball, Edward V.; Mort, Matthew; Phillips, Andrew D.; Stenson, Peter D.; Sebat, Jonathan; Makarov, Vladimir; Ye, Kenny; Yoon, Seungtai C.; Bustamante, Carlos D.; Clark, Andrew G.; Boyko, Adam; Degenhardt, Jeremiah; Gravel, Simon; Gutenkunst, Ryan N.; Kaganovich, Mark; Keinan, Alon; Lacroute, Phil; Ma, Xin; Reynolds, Andy; Clarke, Laura; Flicek, Paul; Cunningham, Fiona; Herrero, Javier; Keenen, Stephen; Kulesha, Eugene; Leinonen, Rasko; McLaren, William M.; Radhakrishnan, Rajesh; Smith, Richard E.; Zalunin, Vadim; Zheng-Bradley, Xiangqun; Korbel, Jan O.; Stütz, Adrian M.; Humphray, Sean; Bauer, Markus; Cheetham, R. Keira; Cox, Tony; Eberle, Michael; James, Terena; Kahn, Scott; Murray, Lisa; Chakravarti, Aravinda; Ye, Kai; De La Vega, Francisco M.; Fu, Yutao; Hyland, Fiona C. L.; Manning, Jonathan M.; McLaughlin, Stephen F.; Peckham, Heather E.; Sakarya, Onur; Sun, Yongming A.; Tsung, Eric F.; Batzer, Mark A.; Konkel, Miriam K.; Walker, Jerilyn A.; Sudbrak, Ralf; Albrecht, Marcus W.; Amstislavskiy, Vyacheslav S.; Herwig, Ralf; Parkhomchuk, Dimitri V.; Sherry, Stephen T.; Agarwala, Richa; Khouri, Hoda M.; Morgulis, Aleksandr O.; Paschall, Justin E.; Phan, Lon D.; Rotmistrovsky, Kirill E.; Sanders, Robert D.; Shumway, Martin F.; Xiao, Chunlin; McVean, Gil A.; Auton, Adam; Iqbal, Zamin; Lunter, Gerton; Marchini, Jonathan L.; Moutsianas, Loukas; Myers, Simon; Tumian, Afidalina; Desany, Brian; Knight, James; Winer, Roger; Craig, David W.; Beckstrom-Sternberg, Steve M.; Christoforides, Alexis; Kurdoglu, Ahmet A.; Pearson, John V.; Sinari, Shripad A.; Tembe, Waibhav D.; Haussler, David; Hinrichs, Angie S.; Katzman, Sol J.; Kern, Andrew; Kuhn, Robert M.; Przeworski, Molly; Hernandez, Ryan D.; Howie, Bryan; Kelley, Joanna L.; Melton, S. Cord; Abecasis, Gonçalo R.; Li, Yun; Anderson, Paul; Blackwell, Tom; Chen, Wei; Cookson, William O.; Ding, Jun; Kang, Hyun Min; Lathrop, Mark; Liang, Liming; Moffatt, Miriam F.; Scheet, Paul; Sidore, Carlo; Snyder, Matthew; Zhan, Xiaowei; Zöllner, Sebastian; Awadalla, Philip; Casals, Ferran; Idaghdour, Youssef; Keebler, John; Stone, Eric A.; Zilversmit, Martine; Jorde, Lynn; Xing, Jinchuan; Eichler, Evan E.; Aksay, Gozde; Alkan, Can; Hajirasouliha, Iman; Hormozdiari, Fereydoun; Kidd, Jeffrey M.; Sahinalp, S. Cenk; Sudmant, Peter H.; Mardis, Elaine R.; Chen, Ken; Chinwalla, Asif; Ding, Li; Koboldt, Daniel C.; McLellan, Mike D.; Dooling, David; Weinstock, George; Wallis, John W.; Wendl, Michael C.; Zhang, Qunyuan; Durbin, Richard M.; Albers, Cornelis A.; Ayub, Qasim; Balasubramaniam, Senduran; Barrett, Jeffrey C.; Carter, David M.; Chen, Yuan; Conrad, Donald F.; Danecek, Petr; Dermitzakis, Emmanouil T.; Hu, Min; Huang, Ni; Hurles, Matt E.; Jin, Hanjun; Jostins, Luke; Keane, Thomas M.; Le, Si Quang; Lindsay, Sarah; Long, Quan; MacArthur, Daniel G.; Montgomery, Stephen B.; Parts, Leopold; Stalker, James; Tyler-Smith, Chris; Walter, Klaudia; Zhang, Yujun; Gerstein, Mark B.; Snyder, Michael; Abyzov, Alexej; Balasubramanian, Suganthi; Bjornson, Robert; Du, Jiang; Grubert, Fabian; Habegger, Lukas; Haraksingh, Rajini; Jee, Justin; Khurana, Ekta; Lam, Hugo Y. K.; Leng, Jing; Mu, Xinmeng Jasmine; Urban, Alexander E.; Zhang, Zhengdong; Li, Yingrui; Luo, Ruibang; Marth, Gabor T.; Garrison, Erik P.; Kural, Deniz; Quinlan, Aaron R.; Stewart, Chip; Stromberg, Michael P.; Ward, Alistair N.; Wu, Jiantao; Lee, Charles; Mills, Ryan E.; Shi, Xinghua; McCarroll, Steven A.; Banks, Eric; DePristo, Mark A.; Handsaker, Robert E.; Hartl, Chris; Korn, Joshua M.; Li, Heng; Nemesh, James C.; Sebat, Jonathan; Makarov, Vladimir; Ye, Kenny; Yoon, Seungtai C.; Degenhardt, Jeremiah; Kaganovich, Mark; Clarke, Laura; Smith, Richard E.; Zheng-Bradley, Xiangqun; Korbel, Jan O.; Humphray, Sean; Cheetham, R. Keira; Eberle, Michael; Kahn, Scott; Murray, Lisa; Ye, Kai; De La Vega, Francisco M.; Fu, Yutao; Peckham, Heather E.; Sun, Yongming A.; Batzer, Mark A.; Konkel, Miriam K.; Walker, Jerilyn A.; Xiao, Chunlin; Iqbal, Zamin; Desany, Brian; Blackwell, Tom; Snyder, Matthew; Xing, Jinchuan; Eichler, Evan E.; Aksay, Gozde; Alkan, Can; Hajirasouliha, Iman; Hormozdiari, Fereydoun; Kidd, Jeffrey M.; Chen, Ken; Chinwalla, Asif; Ding, Li; McLellan, Mike D.; Wallis, John W.; Hurles, Matt E.; Conrad, Donald F.; Walter, Klaudia; Zhang, Yujun; Gerstein, Mark B.; Snyder, Michael; Abyzov, Alexej; Du, Jiang; Grubert, Fabian; Haraksingh, Rajini; Jee, Justin; Khurana, Ekta; Lam, Hugo Y. K.; Leng, Jing; Mu, Xinmeng Jasmine; Urban, Alexander E.; Zhang, Zhengdong; Gibbs, Richard A.; Bainbridge, Matthew; Challis, Danny; Coafra, Cristian; Dinh, Huyen; Kovar, Christie; Lee, Sandy; Muzny, Donna; Nazareth, Lynne; Reid, Jeff; Sabo, Aniko; Yu, Fuli; Yu, Jin; Marth, Gabor T.; Garrison, Erik P.; Indap, Amit; Leong, Wen Fung; Quinlan, Aaron R.; Stewart, Chip; Ward, Alistair N.; Wu, Jiantao; Cibulskis, Kristian; Fennell, Tim J.; Gabriel, Stacey B.; Garimella, Kiran V.; Hartl, Chris; Shefler, Erica; Sougnez, Carrie L.; Wilkinson, Jane; Clark, Andrew G.; Gravel, Simon; Grubert, Fabian; Clarke, Laura; Flicek, Paul; Smith, Richard E.; Zheng-Bradley, Xiangqun; Sherry, Stephen T.; Khouri, Hoda M.; Paschall, Justin E.; Shumway, Martin F.; Xiao, Chunlin; McVean, Gil A.; Katzman, Sol J.; Abecasis, Gonçalo R.; Blackwell, Tom; Mardis, Elaine R.; Dooling, David; Fulton, Lucinda; Fulton, Robert; Koboldt, Daniel C.; Durbin, Richard M.; Balasubramaniam, Senduran; Coffey, Allison; Keane, Thomas M.; MacArthur, Daniel G.; Palotie, Aarno; Scott, Carol; Stalker, James; Tyler-Smith, Chris; Gerstein, Mark B.; Balasubramanian, Suganthi; Chakravarti, Aravinda; Knoppers, Bartha M.; Abecasis, Gonçalo R.; Bustamante, Carlos D.; Gharani, Neda; Gibbs, Richard A.; Jorde, Lynn; Kaye, Jane S.; Kent, Alastair; Li, Taosha; McGuire, Amy L.; McVean, Gil A.; Ossorio, Pilar N.; Rotimi, Charles N.; Su, Yeyang; Toji, Lorraine H.; TylerSmith, Chris; Brooks, Lisa D.; Felsenfeld, Adam L.; McEwen, Jean E.; Abdallah, Assya; Juenger, Christopher R.; Clemm, Nicholas C.; Collins, Francis S.; Duncanson, Audrey; Green, Eric D.; Guyer, Mark S.; Peterson, Jane L.; Schafer, Alan J.; Abecasis, Gonçalo R.; Altshuler, David L.; Auton, Adam; Brooks, Lisa D.; Durbin, Richard M.; Gibbs, Richard A.; Hurles, Matt E.; McVean, Gil A.

    2011-01-01

    High-throughput sequencing technology enables population-level surveys of human genomic variation. Here, we examine the joint allele frequency distributions across continental human populations and present an approach for combining complementary aspects of whole-genome, low-coverage data and targeted high-coverage data. We apply this approach to data generated by the pilot phase of the Thousand Genomes Project, including whole-genome 2–4× coverage data for 179 samples from HapMap European, Asian, and African panels as well as high-coverage target sequencing of the exons of 800 genes from 697 individuals in seven populations. We use the site frequency spectra obtained from these data to infer demographic parameters for an Out-of-Africa model for populations of African, European, and Asian descent and to predict, by a jackknife-based approach, the amount of genetic diversity that will be discovered as sample sizes are increased. We predict that the number of discovered nonsynonymous coding variants will reach 100,000 in each population after ∼1,000 sequenced chromosomes per population, whereas ∼2,500 chromosomes will be needed for the same number of synonymous variants. Beyond this point, the number of segregating sites in the European and Asian panel populations is expected to overcome that of the African panel because of faster recent population growth. Overall, we find that the majority of human genomic variable sites are rare and exhibit little sharing among diverged populations. Our results emphasize that replication of disease association for specific rare genetic variants across diverged populations must overcome both reduced statistical power because of rarity and higher population divergence. PMID:21730125

  1. Endogenous technological and population change under increasing water scarcity

    NASA Astrophysics Data System (ADS)

    Pande, S.; Ertsen, M.; Sivapalan, M.

    2014-08-01

    Ancient civilizations may have dispersed or collapsed under extreme dry conditions. There are indications that the same may hold for modern societies. However, hydroclimatic change cannot be the sole predictor of the fate of contemporary societies in water-scarce regions. This paper focuses on technological change as a factor that may ameliorate the effects of increasing water scarcity and as such counter the effects of hydroclimatic changes. We study the role of technological change on the dynamics of coupled human-water systems, and model technological change as an endogenous process that depends on many factors intrinsic to coupled human-water dynamics. We do not treat technology as an exogenous random sequence of events, but assume that it results from societal actions. While the proposed model is a rather simple model of a coupled human-water system, it is shown to be capable of replicating patterns of technological, population, production and consumption per capita changes. The model demonstrates that technological change may indeed ameliorate the effects of increasing water scarcity, but typically it does so only to a certain extent. In general we find that endogenous technology change under increasing water scarcity helps to delay the peak of population size before it inevitably starts to decline. We also analyze the case when water remains constant over time and find that co-evolutionary trajectories can never grow at a constant rate; rather the rate itself grows with time. Thus our model does not predict a co-evolutionary trajectory of a socio-hydrological system where technological innovation harmoniously provides for a growing population. It allows either for an explosion or an eventual dispersal of population. The latter occurs only under increasing water scarcity. As a result, we draw the conclusion that declining consumption per capita despite technological advancement and increase in aggregate production may serve as a useful predictor of upcoming decline in contemporary societies in water-scarce basins.

  2. Patterns of demographic change in the Americas.

    PubMed

    Ubelaker, D H

    1992-06-01

    Considerable scholarly debate has focused on the nature of demographic change in the Americas before and after 1492. Recent research on human skeletal samples and related archeological materials suggests that morbidity and mortality were increasing throughout much of the Western Hemisphere before 1492 in response to increased population density, increased sedentism, and changing subsistence. The evidence suggests that after 1492 population reduction was caused not by continental pandemics but by localized or regional epidemics augmented by social and economic disruption. The twentieth century has witnessed remarkable Native American population recovery, fueled both by improvements in health care and changing definitions of "being Indian."

  3. Climatic Change and Human Evolution.

    ERIC Educational Resources Information Center

    Garratt, John R.

    1995-01-01

    Traces the history of the Earth over four billion years, and shows how climate has had an important role to play in the evolution of humans. Posits that the world's rapidly growing human population and its increasing use of energy is the cause of present-day changes in the concentrations of greenhouse gases in the atmosphere. (Author/JRH)

  4. Plants, arthropods, and birds of the Rio Grande [chapter 7

    Treesearch

    Deborah M. Finch; Gale L. Wolters; Wang Yong; Mary Jean Mund

    1995-01-01

    Human populations have increased dramatically along the Rio Grande since European settlement. Human use of water for irrigation and consumption, and human use of land for agriculture, urban centers, livestock grazing, and recreation have changed Rio Grande ecosystems by altering flood cycles, channel geomorphology, upslope processes, and water quality and quantity....

  5. Natural bounds on herbivorous coral reef fishes

    PubMed Central

    Hoey, Andrew S.; Williams, Gareth J.; Williams, Ivor D.

    2016-01-01

    Humans are an increasingly dominant driver of Earth's biological communities, but differentiating human impacts from natural drivers of ecosystem state is crucial. Herbivorous fish play a key role in maintaining coral dominance on coral reefs, and are widely affected by human activities, principally fishing. We assess the relative importance of human and biophysical (habitat and oceanographic) drivers on the biomass of five herbivorous functional groups among 33 islands in the central and western Pacific Ocean. Human impacts were clear for some, but not all, herbivore groups. Biomass of browsers, large excavators, and of all herbivores combined declined rapidly with increasing human population density, whereas grazers, scrapers, and detritivores displayed no relationship. Sea-surface temperature had significant but opposing effects on the biomass of detritivores (positive) and browsers (negative). Similarly, the biomass of scrapers, grazers, and detritivores correlated with habitat structural complexity; however, relationships were group specific. Finally, the biomass of browsers and large excavators was related to island geomorphology, both peaking on low-lying islands and atolls. The substantial variability in herbivore populations explained by natural biophysical drivers highlights the need for locally appropriate management targets on coral reefs. PMID:27881745

  6. A COMPARISON OF ENVIRONMENTAL EXPOSURES TO SELECTED AIR POLLUTANTS BETWEEN TWO APPARENT SOCIO-ECONOMICALLY DIVERSE POPULATIONS IN THE RESEARCH TRIANGLE PARK METROPOLITAN AREA

    EPA Science Inventory

    Human exposures to certain size fractions of ambient air Particulate Matter (PM) have been related to apparent associations in increased mortality and morbidity in the U.S. population. This risk association would appear to be relevant to the general population and even more pro...

  7. Simple deterministic models and applications. Comment on "Coupled disease-behavior dynamics on complex networks: A review" by Z. Wang et al.

    NASA Astrophysics Data System (ADS)

    Yang, Hyun Mo

    2015-12-01

    Currently, discrete modellings are largely accepted due to the access to computers with huge storage capacity and high performance processors and easy implementation of algorithms, allowing to develop and simulate increasingly sophisticated models. Wang et al. [7] present a review of dynamics in complex networks, focusing on the interaction between disease dynamics and human behavioral and social dynamics. By doing an extensive review regarding to the human behavior responding to disease dynamics, the authors briefly describe the complex dynamics found in the literature: well-mixed populations networks, where spatial structure can be neglected, and other networks considering heterogeneity on spatially distributed populations. As controlling mechanisms are implemented, such as social distancing due 'social contagion', quarantine, non-pharmaceutical interventions and vaccination, adaptive behavior can occur in human population, which can be easily taken into account in the dynamics formulated by networked populations.

  8. An early warning system to forecast the close of the spring burning window from satellite-observed greenness.

    PubMed

    Pickell, Paul D; Coops, Nicholas C; Ferster, Colin J; Bater, Christopher W; Blouin, Karen D; Flannigan, Mike D; Zhang, Jinkai

    2017-10-27

    Spring represents the peak of human-caused wildfire events in populated boreal forests, resulting in catastrophic loss of property and human life. Human-caused wildfire risk is anticipated to increase in northern forests as fuels become drier, on average, under warming climate scenarios and as population density increases within formerly remote regions. We investigated springtime human-caused wildfire risk derived from satellite-observed vegetation greenness in the early part of the growing season, a period of increased ignition and wildfire spread potential from snow melt to vegetation green-up with the aim of developing an early warning wildfire risk system. The initial system was developed for 392,856 km 2 of forested lands with satellite observations available prior to the start of the official wildfire season and predicted peak human-caused wildfire activity with 10-day accuracy for 76% of wildfire-protected lands by March 22. The early warning system could have significant utility as a cost-effective solution for wildfire managers to prioritize the deployment of wildfire protection resources in wildfire-prone landscapes across boreal-dominated ecosystems of North America, Europe, and Russia using open access Earth observations.

  9. Considerations for a Human Rights Impact Assessment of a Population Wide Treatment for HIV Prevention Intervention.

    PubMed

    Hanefeld, Johanna; Bond, Virginia; Seeley, Janet; Lees, Shelley; Desmond, Nicola

    2015-12-01

    Increasing attention is being paid to the potential of anti-retroviral treatment (ART) for HIV prevention. The possibility of eliminating HIV from a population through a universal test and treat intervention, where all people within a population are tested for HIV and all positive people immediately initiated on ART, as part of a wider prevention intervention, was first proposed in 2009. Several clinical trials testing this idea are now in inception phase. An intervention which relies on universally testing the entire population for HIV will pose challenges to human rights, including obtaining genuine consent to testing and treatment. It also requires a context in which people can live free from fear of stigma, discrimination and violence, and can access services they require. These challenges are distinct from the field of medical ethics which has traditionally governed clinical trials and focuses primarily on patient researcher relationship. This paper sets out the potential impact of a population wide treatment as prevention intervention on human rights. It identifies five human right principles of particular relevance: participation, accountability, the right to health, non-discrimination and equality, and consent and confidentiality. The paper proposes that explicit attention to human rights can strengthen a treatment as prevention intervention, contribute to mediating likely health systems challenges and offer insights on how to reach all sections of the population. © 2013 John Wiley & Sons Ltd.

  10. Genomic and cranial phenotype data support multiple modern human dispersals from Africa and a southern route into Asia

    PubMed Central

    Reyes-Centeno, Hugo; Ghirotto, Silvia; Détroit, Florent; Grimaud-Hervé, Dominique; Barbujani, Guido; Harvati, Katerina

    2014-01-01

    Despite broad consensus on Africa as the main place of origin for anatomically modern humans, their dispersal pattern out of the continent continues to be intensely debated. In extant human populations, the observation of decreasing genetic and phenotypic diversity at increasing distances from sub-Saharan Africa has been interpreted as evidence for a single dispersal, accompanied by a series of founder effects. In such a scenario, modern human genetic and phenotypic variation was primarily generated through successive population bottlenecks and drift during a rapid worldwide expansion out of Africa in the Late Pleistocene. However, recent genetic studies, as well as accumulating archaeological and paleoanthropological evidence, challenge this parsimonious model. They suggest instead a “southern route” dispersal into Asia as early as the late Middle Pleistocene, followed by a separate dispersal into northern Eurasia. Here we test these competing out-of-Africa scenarios by modeling hypothetical geographical migration routes and assessing their correlation with neutral population differentiation, as measured by genetic polymorphisms and cranial shape variables of modern human populations from Africa and Asia. We show that both lines of evidence support a multiple-dispersals model in which Australo-Melanesian populations are relatively isolated descendants of an early dispersal, whereas other Asian populations are descended from, or highly admixed with, members of a subsequent migration event. PMID:24753576

  11. Developing a Renewable Energy Awareness Scale for Pre-Service Chemistry Teachers

    ERIC Educational Resources Information Center

    Morgil, Inci; Secken, Nilgun; Yucel, A. Seda; Ozyalcin Oskay, Ozge; Yavuz, Soner; Ural, Evrim

    2006-01-01

    In times when human beings used to live in a natural environment, their needs were also provided for by natural resources. With the increase in population over time, human beings started to look for new resources willing to get "the most" and "the fastest". Just like the invention of steam, first, they increased the density of the resources and…

  12. Effects of habitat fragmentation on a stream-dwelling species, the flattened musk turtle Sternotherus depressus

    USGS Publications Warehouse

    Dodd, C.K.

    1990-01-01

    The flattened musk turtle Sternotherus depressus has disappeared from more than half of its former range because of habitat modifications to stream and river channels in the Warrior River Basin, Alabama. Only 6·9% of its probable historic range contains relatively healthy populations, and most populations are fragmented by extensive areas of unsuitable habitat. Turtles in the best remaining habitats continue to be vulnerable to disease and human-related disturbance, collecting and habitat modification. These factors lead to population declines and abnormal population structure. Habitat fragmentation, especially in small populations, increases vulnerability to human-caused catastrophes and demographic accidents, and could lead to eventual extinction. The threats facing fragmented populations of this turtle probably parallel those affecting many other stream-dwelling species throughout the southeastern United States.

  13. Biodiversity Areas under Threat: Overlap of Climate Change and Population Pressures on the World's Biodiversity Priorities.

    PubMed

    Aukema, Juliann E; Pricope, Narcisa G; Husak, Gregory J; Lopez-Carr, David

    2017-01-01

    Humans and the ecosystem services they depend on are threatened by climate change. Places with high or growing human population as well as increasing climate variability, have a reduced ability to provide ecosystem services just as the need for these services is most critical. A spiral of vulnerability and ecosystem degradation often ensues in such places. We apply different global conservation schemes as proxies to examine the spatial relation between wet season precipitation, population change over three decades, and natural resource conservation. We pose two research questions: 1) Where are biodiversity and ecosystem services vulnerable to the combined effects of climate change and population growth? 2) Where are human populations vulnerable to degraded ecosystem services? Results suggest that globally only about 20% of the area between 50 degrees latitude North and South has experienced significant change-largely wetting-in wet season precipitation. Approximately 40% of rangelands and 30% of rainfed agriculture lands have experienced significant precipitation changes, with important implications for food security. Over recent decades a number of critical conservation areas experienced high population growth concurrent with significant wetting or drying (e.g. the Horn of Africa, Himalaya, Western Ghats, and Sri Lanka), posing challenges not only for human adaptation but also to the protection and sustenance of biodiversity and ecosystem services. Identifying areas of climate and population risk and their overlap with conservation priorities can help to target activities and resources that promote biodiversity and ecosystem services while improving human well-being.

  14. Biodiversity Areas under Threat: Overlap of Climate Change and Population Pressures on the World’s Biodiversity Priorities

    PubMed Central

    Pricope, Narcisa G.; Husak, Gregory J.; Lopez-Carr, David

    2017-01-01

    Humans and the ecosystem services they depend on are threatened by climate change. Places with high or growing human population as well as increasing climate variability, have a reduced ability to provide ecosystem services just as the need for these services is most critical. A spiral of vulnerability and ecosystem degradation often ensues in such places. We apply different global conservation schemes as proxies to examine the spatial relation between wet season precipitation, population change over three decades, and natural resource conservation. We pose two research questions: 1) Where are biodiversity and ecosystem services vulnerable to the combined effects of climate change and population growth? 2) Where are human populations vulnerable to degraded ecosystem services? Results suggest that globally only about 20% of the area between 50 degrees latitude North and South has experienced significant change–largely wetting–in wet season precipitation. Approximately 40% of rangelands and 30% of rainfed agriculture lands have experienced significant precipitation changes, with important implications for food security. Over recent decades a number of critical conservation areas experienced high population growth concurrent with significant wetting or drying (e.g. the Horn of Africa, Himalaya, Western Ghats, and Sri Lanka), posing challenges not only for human adaptation but also to the protection and sustenance of biodiversity and ecosystem services. Identifying areas of climate and population risk and their overlap with conservation priorities can help to target activities and resources that promote biodiversity and ecosystem services while improving human well-being. PMID:28125659

  15. Malaria and Other Vector-Borne Infection Surveillance in the U.S. Department of Defense Armed Forces Health Surveillance Center-Global Program: Review of 2009 Accomplishments

    DTIC Science & Technology

    2011-03-04

    global travel, tourism and trade, and blurred lines of demarcation between zoonotic VBI reservoirs and human populations increase vector exposure. Urban...Unprecedented levels of global travel, tourism and trade, and blurred lines of demarcation between zoonotic VBI reservoirs and human populations...made in 2009 to enhance or establish hospi- tal-based febrile illness surveillance platforms in Azer- baijan, Bolivia, Cambodia, Ecuador , Georgia

  16. Adaptive Management for a Turbulent Future

    EPA Science Inventory

    The challenges that face humanity today differ from the past because as the scale of human influence has increased, our biggest challenges have become global in nature, and formerly local problems that could be addressed by shifting populations or switching resources, now aggrega...

  17. A Reporting System to Protect the Human Rights of People Living with HIV and Key Populations.

    PubMed

    Williamson, R Taylor; Fiscian, Vivian; Olson, Ryan Ubuntu; Poku, Fred Nana; Whittal, Joseph

    2017-12-01

    People living with HIV and key populations face human rights violations that affect their access to health services, relationships in their communities, housing options, and employment. To address these violations, government and civil society organizations in Ghana developed a discrimination reporting system managed by the Commission on Human Rights and Administrative Justice that links people living with HIV and key populations to legal services. This article presents findings on how Ghanaian stakeholders built this reporting system and discusses preliminary data on its impact. To organize our analysis, we used a conceptual framework that outlines the legal frameworks that protect human rights, the institutions that promote access to justice, and the mechanisms that link people living with HIV and key populations to legal services. Using in-depth interviews, we show that targeted technical assistance increased stakeholders' knowledge of issues that affect people living with HIV and key populations, strengthened these stakeholders' commitment to address discrimination, streamlined case management systems, and improved relationships between civil society and the government. Through case review, we find that most discrimination happens when accessing government services, inside communities and families, and in the workplace. Finally, we describe implications for other human rights commissions that are considering using a reporting system to protect human rights, including using legal frameworks, developing case management systems, and working with civil society.

  18. Alaskan brown bears, humans, and habituation

    USGS Publications Warehouse

    Smith, Thomas; Herrero, Stephen; DeBruyn, Terry D.

    2005-01-01

    We present a new paradigm for understanding habituation and the role it plays in brown bear (Ursus arctos) populations and interactions with humans in Alaska. We assert that 3 forms of habituation occur in Alaska: bear-to-bear, bear-to-human, and human-to-bear. We present data that supports our theory that bear density is an important factor influencing a bear’s overt reaction distance (ORD); that as bear density increases, overt reaction distance decreases, as does the likelihood of bear– human interactions. We maintain that the effects of bear-to-bear habituation are largely responsible for not only shaping bear aggregations but also for creating the relatively safe environment for bear viewing experienced at areas where there are high densities of brown bears. By promoting a better understanding of the forces that shape bear social interactions within populations and with humans that mingle with them, we can better manage human activities and minimize bear–human conflict.

  19. Persons With Disabilities as an Unrecognized Health Disparity Population

    PubMed Central

    Walker, Deborah Klein; Correa-De-Araujo, Rosaly

    2015-01-01

    Disability is an emerging field within public health; people with significant disabilities account for more than 12% of the US population. Disparity status for this group would allow federal and state governments to actively work to reduce inequities. We summarize the evidence and recommend that observed differences are sufficient to meet the criteria for health disparities: population-level differences in health outcomes that are related to a history of wide-ranging disadvantages, which are avoidable and not primarily caused by the underlying disability. We recommend future research and policy directions to address health inequities for individuals with disabilities; these include improved access to health care and human services, increased data to support decision-making, strengthened health and human services workforce capacity, explicit inclusion of disability in public health programs, and increased emergency preparedness. PMID:25689212

  20. Epidemiological evidence for a health risk from mobile phone base stations.

    PubMed

    Khurana, Vini G; Hardell, Lennart; Everaert, Joris; Bortkiewicz, Alicja; Carlberg, Michael; Ahonen, Mikko

    2010-01-01

    Human populations are increasingly exposed to microwave/radiofrequency (RF) emissions from wireless communication technology, including mobile phones and their base stations. By searching PubMed, we identified a total of 10 epidemiological studies that assessed for putative health effects of mobile phone base stations. Seven of these studies explored the association between base station proximity and neurobehavioral effects and three investigated cancer. We found that eight of the 10 studies reported increased prevalence of adverse neurobehavioral symptoms or cancer in populations living at distances < 500 meters from base stations. None of the studies reported exposure above accepted international guidelines, suggesting that current guidelines may be inadequate in protecting the health of human populations. We believe that comprehensive epidemiological studies of long-term mobile phone base station exposure are urgently required to more definitively understand its health impact.

  1. Impacts of Extreme Events on Human Health. Chapter 4

    NASA Technical Reports Server (NTRS)

    Bell, Jesse E.; Herring, Stephanie C.; Jantarasami, Lesley; Adrianopoli, Carl; Benedict, Kaitlin; Conlon, Kathryn; Escobar, Vanessa; Hess, Jeremy; Luvall, Jeffrey; Garcia-Pando, Carlos Perez; hide

    2016-01-01

    Increased Exposure to Extreme Events Key Finding 1: Health impacts associated with climate-related changes in exposure to extreme events include death, injury, or illness; exacerbation of underlying medical conditions; and adverse effects on mental health[High Confidence]. Climate change will increase exposure risk in some regions of the United States due to projected increases in the frequency and/or intensity of drought, wildfires, and flooding related to extreme precipitation and hurricanes [Medium Confidence].Disruption of Essential Infrastructure Key Finding 2: Many types of extreme events related to climate change cause disruption of infrastructure, including power, water, transportation, and communication systems, that are essential to maintaining access to health care and emergency response services and safeguarding human health [High Confidence].Vulnerability to Coastal Flooding Key Finding 3: Coastal populations with greater vulnerability to health impacts from coastal flooding include persons with disabilities or other access and functional needs, certain populations of color, older adults, pregnant women and children, low-income populations, and some occupational groups [High Confidence].Climate change will increase exposure risk to coastal flooding due to increases in extreme precipitation and in hurricane intensity and rainfall rates, as well as sea level rise and the resulting increases in storm surge.

  2. Gracility of the modern Homo sapiens skeleton is the result of decreased biomechanical loading.

    PubMed

    Ryan, Timothy M; Shaw, Colin N

    2015-01-13

    The postcranial skeleton of modern Homo sapiens is relatively gracile compared with other hominoids and earlier hominins. This gracility predisposes contemporary humans to osteoporosis and increased fracture risk. Explanations for this gracility include reduced levels of physical activity, the dissipation of load through enlarged joint surfaces, and selection for systemic physiological characteristics that differentiate modern humans from other primates. This study considered the skeletal remains of four behaviorally diverse recent human populations and a large sample of extant primates to assess variation in trabecular bone structure in the human hip joint. Proximal femur trabecular bone structure was quantified from microCT data for 229 individuals from 31 extant primate taxa and 59 individuals from four distinct archaeological human populations representing sedentary agriculturalists and mobile foragers. Analyses of mass-corrected trabecular bone variables reveal that the forager populations had significantly higher bone volume fraction, thicker trabeculae, and consequently lower relative bone surface area compared with the two agriculturalist groups. There were no significant differences between the agriculturalist and forager populations for trabecular spacing, number, or degree of anisotropy. These results reveal a correspondence between human behavior and bone structure in the proximal femur, indicating that more highly mobile human populations have trabecular bone structure similar to what would be expected for wild nonhuman primates of the same body mass. These results strongly emphasize the importance of physical activity and exercise for bone health and the attenuation of age-related bone loss.

  3. Reconstructing human pancreatic differentiation by mapping specific cell populations during development

    PubMed Central

    Ramond, Cyrille; Glaser, Nicolas; Berthault, Claire; Ameri, Jacqueline; Kirkegaard, Jeannette Schlichting; Hansson, Mattias; Honoré, Christian; Semb, Henrik; Scharfmann, Raphaël

    2017-01-01

    Information remains scarce on human development compared to animal models. Here, we reconstructed human fetal pancreatic differentiation using cell surface markers. We demonstrate that at 7weeks of development, the glycoprotein 2 (GP2) marks a multipotent cell population that will differentiate into the acinar, ductal or endocrine lineages. Development towards the acinar lineage is paralleled by an increase in GP2 expression. Conversely, a subset of the GP2+ population undergoes endocrine differentiation by down-regulating GP2 and CD142 and turning on NEUROG3, a marker of endocrine differentiation. Endocrine maturation progresses by up-regulating SUSD2 and lowering ECAD levels. Finally, in vitro differentiation of pancreatic endocrine cells derived from human pluripotent stem cells mimics key in vivo events. Our work paves the way to extend our understanding of the origin of mature human pancreatic cell types and how such lineage decisions are regulated. DOI: http://dx.doi.org/10.7554/eLife.27564.001 PMID:28731406

  4. Current Characteristics and Trends of the Tracked Satellite Population in the Human Space Flight Regime

    NASA Technical Reports Server (NTRS)

    Johnson, Nicholas L.

    2006-01-01

    Since the end of the Apollo program in 1972, human space flight has been restricted to altitudes below 600 km above the Earth s surface with most missions restricted to a ceiling below 400 km. An investigation of the tracked satellite population transiting and influencing the human space flight regime during the past 11 years (equivalent to a full solar cycle) has recently been completed. The overall effects of satellite breakups and solar activity are typically less pronounced in the human space flight regime than other regions of low Earth orbit. As of January 2006 nearly 1500 tracked objects resided in or traversed the human space flight regime, although two-thirds of these objects were in orbits of moderate to high eccentricity, significantly reducing their effect on human space flight safety. During the period investigated, the spatial density of tracked objects in the 350-400 km altitude regime of the International Space Station demonstrated a steady decline, actually decreasing by 50% by the end of the period. On the other hand, the region immediately above 600 km experienced a significant increase in its population density. This regime is important for future risk assessments, since this region represents the reservoir of debris which will influence human space flight safety in the future. The paper seeks to put into sharper perspective the risks posed to human space flight by the tracked satellite population, as well as the influences of solar activity and the effects of compliance with orbital debris mitigation guidelines on human space flight missions. Finally, the methods and successes of characterizing the population of smaller debris at human space flight regimes are addressed.

  5. Population education for social betterment.

    PubMed

    Mukhi, S

    1983-01-26

    In India primary education has increased 3 times in the last 30 years. Over this same period middle school education has increased 4 times, higher secondary education 5 times, and university level education over 6 times. The number of universities alone increased from 19 in 1950 to 118 by 1981. The inconsistencies brought about by rapid population growth may be judged by the fact that while the number of institutions and the enrollment of students has expanded beyond measure, the number of illiterate persons has risen from 386 million in 1971 to 446 million in 1981. Clearly, education is vital for human resource development. In political terms, human resource development prepares a population for adult participation in political processes. From social and cultural perspectives, the development of human resources helps people to lead fuller and richer lives. Population means people, and people need food, clothing, homes, education, transportation, health services, and jobs. As long as a country's resources can satisfy the essential needs of its population, there is no population problem. If the population grows faster than the rate at which the basic needs of each individual can be met, the buildup of such a situation produces a crisis of gigantic dimensions. To meet basic requirements, India needs to provide annually an additional 12 million tons of foodgrains, 188 million meters of cloth, 2.5 million houses, along with schools, teachers, and jobs over and above what is currently available. Another need is for fresh air, pure water, and space to live in. The question is how is this need to be met when the earth is a finite sphere. What will happen when the world's 3.5 billion people double into a staggering 7 billion by the end of the 20th century. It is because of this concern for family well being and the betterment of human resources that the Family Planning Association of India has since 1969 undertaken innovative pilot programs in popultion education for the younger generation, for teachers, social workers, and other concerned groups. The government of India promotes population education for school and out-of-school youths through the 5-year national population education project for schools and through the adult education project for out-of-school youth.

  6. Immunomodulation of human B cells following treatment with intravenous immunoglobulins involves increased phosphorylation of extracellular signal-regulated kinases 1 and 2.

    PubMed

    Dussault, Nathalie; Ducas, Eric; Racine, Claudia; Jacques, Annie; Paré, Isabelle; Côté, Serge; Néron, Sonia

    2008-11-01

    In the treatment of autoimmune diseases, intravenous Igs (IVIg) are assumed to modulate immune cells through the binding of surface receptors. IVIg act upon definite human B cell populations to modulate Ig repertoire, and such modulation might proceed through intracellular signaling. However, the heterogeneity of human B cell populations complicates investigations of the intracellular pathways involved in IVIg-induced B cell modulation. The aim of this study was to establish a model allowing the screening of IVIg signal transduction in human B cell lines and to attempt transposing observations made in cell lines to normal human B lymphocytes. Nine human B cell lines were treated with IVIg with the goal of selecting the most suitable model for human B lymphocytes. The IgG(+) DB cell line, whose response was similar to that of human B lymphocytes, showed reduced IVIg modulation following addition of PD98059, an inhibitor of extracellular signal-regulated protein kinase 1/2 (ERK1/2). The IVIg-induced ERK1/2 phosphorylation was indeed proportional to the dosage of monomeric IVIg used when tested on DB cells as well as Pfeiffer cells, another IgG(+) cell line. In addition, two other intermediates, Grb2-associated binder 1 (Gab1) and Akt, showed increased phosphorylation in IVIg-treated DB cells. IVIg induction of ERK1/2 phosphorylation was finally observed in peripheral human B lymphocytes, specifically within the IgG(+) B cell population. In conclusion, IVIg immunomodulation of human B cells can thus be linked to intracellular transduction pathways involving the phosphorylation of ERK1/2, which in combination with Gab1 and Akt, may be related to B cell antigen receptor signaling.

  7. Genetic erosion impedes adaptive responses to stressful environments

    PubMed Central

    Bijlsma, R; Loeschcke, Volker

    2012-01-01

    Biodiversity is increasingly subjected to human-induced changes of the environment. To persist, populations continually have to adapt to these often stressful changes including pollution and climate change. Genetic erosion in small populations, owing to fragmentation of natural habitats, is expected to obstruct such adaptive responses: (i) genetic drift will cause a decrease in the level of adaptive genetic variation, thereby limiting evolutionary responses; (ii) inbreeding and the concomitant inbreeding depression will reduce individual fitness and, consequently, the tolerance of populations to environmental stress. Importantly, inbreeding generally increases the sensitivity of a population to stress, thereby increasing the amount of inbreeding depression. As adaptation to stress is most often accompanied by increased mortality (cost of selection), the increase in the ‘cost of inbreeding’ under stress is expected to severely hamper evolutionary adaptive processes. Inbreeding thus plays a pivotal role in this process and is expected to limit the probability of genetically eroded populations to successfully adapt to stressful environmental conditions. Consequently, the dynamics of small fragmented populations may differ considerably from large nonfragmented populations. The resilience of fragmented populations to changing and deteriorating environments is expected to be greatly decreased. Alleviating inbreeding depression, therefore, is crucial to ensure population persistence. PMID:25568035

  8. Human-carnivore conflict in China: a review of current approaches with recommendations for improved management.

    PubMed

    Pettigrew, Melissa; Xie, Yan; Kang, Aili; Rao, Madhu; Goodrich, John; Liu, Tong; Berger, Joshua

    2012-06-01

    Human-wildlife conflict (HWC) is a conservation concern that increasingly threatens the continued existence of some of the world's most endangered species. With an increase in human population, urban sprawl and subsequent encroachment on wild land, human and wildlife interaction has become inevitable. In the majority of cases, this interaction results in a negative outcome for humans, wildlife or both. In China, these key elements, along with a decrease in wild prey species, have resulted in the expansion of HWC encounters, and the need for alleviating this conflict has become a conservation priority. Loss of human life, livestock and/or crops is most often the catalysts that fuel HWC. Techniques to alleviate conflict around the world have included preventative measures and mitigation techniques, such as financial compensation and other incentive programs. Both types of measures have had variable success. We review the current status of human-carnivore conflict management in China, and, drawing lessons from around the globe, we make recommendations for improving conservation management in China. For example, an increase in law enforcement in nature reserves is vital to reducing human disturbance in prime carnivore habitat, thereby reducing conflict encounters. Also, modifications to current wildlife compensation programs, so that they are linked with preventative measures, will ensure that moral hazards are avoided. Furthermore, investigating the potential for a community self-financed insurance scheme to fund compensation and increasing efforts to restore wild prey populations will improve the outcome for wildlife conservation. Ultimately, HWC management in China will greatly benefit from an integrative approach. © 2012 ISZS, Blackwell Publishing and IOZ/CAS.

  9. Ticks collected from humans, domestic animals, and wildlife in Yucatan, Mexico.

    PubMed

    Rodríguez-Vivas, R I; Apanaskevich, D A; Ojeda-Chi, M M; Trinidad-Martínez, I; Reyes-Novelo, E; Esteve-Gassent, M D; Pérez de León, A A

    2016-01-15

    Domestic animals and wildlife play important roles as reservoirs of zoonotic pathogens that are transmitted to humans by ticks. Besides their role as vectors of several classes of microorganisms of veterinary and public health relevance, ticks also burden human and animal populations through their obligate blood-feeding habit. It is estimated that in Mexico there are around 100 tick species belonging to the Ixodidae and Argasidae families. Information is lacking on tick species that affect humans, domestic animals, and wildlife through their life cycle. This study was conducted to bridge that knowledge gap by inventorying tick species that infest humans, domestic animals and wildlife in the State of Yucatan, Mexico. Amblyomma ticks were observed as euryxenous vertebrate parasites because they were found parasitizing 17 animal species and human. Amblyomma mixtum was the most eryxenous species found in 11 different animal species and humans. Both A. mixtum and A. parvum were found parasitizing humans. Ixodes near affinis was the second most abundant species parasitizing six animal species (dogs, cats, horses, white-nosed coati, white-tail deer and black vulture) and was found widely across the State of Yucatan. Ixodid tick populations may increase in the State of Yucatan with time due to animal production intensification, an increasing wildlife population near rural communities because of natural habitat reduction and fragmentation. The diversity of ticks across host taxa documented here highlights the relevance of ecological information to understand tick-host dynamics. This knowledge is critical to inform public health and veterinary programs for the sustainable control of ticks and tick-borne diseases. Copyright © 2015. Published by Elsevier B.V.

  10. TB in Vulnerable Populations

    PubMed Central

    Ugarte-Gil, César; Caro, Godofredo; Aylas, Rula; Castro, César; Lema, Claudia

    2016-01-01

    Abstract This article analyzes the factors associated with vulnerability of the Ashaninka, the most populous indigenous Peruvian Amazonian people, to tuberculosis (TB). By applying a human rights-based analytical framework that assesses public policy against human rights standards and principles, and by offering a step-by-step framework for a full assessment of compliance, it provides evidence of the relationship between the incidence of TB among the Ashaninka and Peru’s poor level of compliance with its human rights obligations. The article argues that one of the main reasons for the historical vulnerability of the Ashaninka to diseases such as TB is a lack of political will on the part of the national government to increase public health spending, ensure that resources reach the most vulnerable population, and adopt and invest in a culturally appropriate health system. PMID:27780999

  11. Anthropogenically induced adaptation to invade (AIAI): contemporary adaptation to human-altered habitats within the native range can promote invasions

    PubMed Central

    Hufbauer, Ruth A; Facon, Benoît; Ravigné, Virginie; Turgeon, Julie; Foucaud, Julien; Lee, Carol E; Rey, Olivier; Estoup, Arnaud

    2012-01-01

    Adaptive evolution is currently accepted as playing a significant role in biological invasions. Adaptations relevant to invasions are typically thought to occur either recently within the introduced range, as an evolutionary response to novel selection regimes, or within the native range, because of long-term adaptation to the local environment. We propose that recent adaptation within the native range, in particular adaptations to human-altered habitat, could also contribute to the evolution of invasive populations. Populations adapted to human-altered habitats in the native range are likely to increase in abundance within areas frequented by humans and associated with human transport mechanisms, thus enhancing the likelihood of transport to a novel range. Given that habitats are altered by humans in similar ways worldwide, as evidenced by global environmental homogenization, propagules from populations adapted to human-altered habitats in the native range should perform well within similarly human-altered habitats in the novel range. We label this scenario ‘Anthropogenically Induced Adaptation to Invade’. We illustrate how it differs from other evolutionary processes that may occur during invasions, and how it can help explain accelerating rates of invasions. PMID:25568032

  12. Current status of Mycobacterium avium subspecies paratuberculosis infection in animals & humans in India: What needs to be done?

    PubMed

    Singh, Ajay Vir; Chauhan, Devendra Singh; Singh, Shoor Vir; Kumar, Vijay; Singh, Abhinendra; Yadav, Anjali; Yadav, Virendra Singh

    2016-11-01

    Mycobacterium avium subspecies paratuberculosis (MAP) has emerged as a major health problem for domestic livestock and human beings. Reduced per animal productivity of domestic livestock seriously impacts the economics of dairy farming globally. High to very high bioload of MAP in domestic livestock and also in the human population has been reported from north India. Presence of live MAP bacilli in commercial supplies of raw and pasteurized milk and milk products indicates its public health significance. MAP is not inactivated during pasteurization, therefore, entering into human food chain daily. Recovery of MAP from patients with inflammatory bowel disease or Crohn's disease and animal healthcare workers suffering with chronic gastrointestinal problems indicate a close association of MAP with a number of chronic and other diseases affecting human health. Higher bioload of MAP in the animals increases the risk of exposure to the human population with MAP. This review summarizes the current status of MAP infection in animals as well as in human beings and also highlights the prospects of effective management and control of disease in animals to reduce the risk of exposure to human population.

  13. Three types of rescue can avert extinction in a changing environment

    USDA-ARS?s Scientific Manuscript database

    Setting aside high quality, large areas of habitat to protect threatened populations is becoming increasingly difficult as humans fragment and degrade the environment. Biologists and managers therefore must determine the best way to shepherd small populations through the dual challenges of reduction...

  14. Human Papillomavirus Vaccination at a Time of Changing Sexual Behavior

    PubMed Central

    Lazzarato, Fulvio; Brisson, Marc; Franceschi, Silvia

    2016-01-01

    Human papillomavirus (HPV) prevalence varies widely worldwide. We used a transmission model to show links between age-specific sexual patterns and HPV vaccination effectiveness. We considered rural India and the United States as examples of 2 heterosexual populations with traditional age-specific sexual behavior and gender-similar age-specific sexual behavior, respectively. We simulated these populations by using age-specific rates of sexual activity and age differences between sexual partners and found that transitions from traditional to gender-similar sexual behavior in women <35 years of age can result in increased (2.6-fold in our study) HPV16 prevalence. Our model shows that reductions in HPV16 prevalence are larger if vaccination occurs in populations before transitions in sexual behavior and that increased risk for HPV infection attributable to transition is preventable by early vaccination. Our study highlights the importance of using time-limited opportunities to introduce HPV vaccination in traditional populations before changes in age-specific sexual patterns occur. PMID:26691673

  15. Human Papillomavirus Vaccination at a Time of Changing Sexual Behavior.

    PubMed

    Baussano, Iacopo; Lazzarato, Fulvio; Brisson, Marc; Franceschi, Silvia

    2016-01-01

    Human papillomavirus (HPV) prevalence varies widely worldwide. We used a transmission model to show links between age-specific sexual patterns and HPV vaccination effectiveness. We considered rural India and the United States as examples of 2 heterosexual populations with traditional age-specific sexual behavior and gender-similar age-specific sexual behavior, respectively. We simulated these populations by using age-specific rates of sexual activity and age differences between sexual partners and found that transitions from traditional to gender-similar sexual behavior in women <35 years of age can result in increased (2.6-fold in our study) HPV16 prevalence. Our model shows that reductions in HPV16 prevalence are larger if vaccination occurs in populations before transitions in sexual behavior and that increased risk for HPV infection attributable to transition is preventable by early vaccination. Our study highlights the importance of using time-limited opportunities to introduce HPV vaccination in traditional populations before changes in age-specific sexual patterns occur.

  16. Potentially Extreme Population Displacement and Concentration in the Tropics Under Non-Extreme Warming

    NASA Astrophysics Data System (ADS)

    Hsiang, Solomon M.; Sobel, Adam H.

    2016-06-01

    Evidence increasingly suggests that as climate warms, some plant, animal, and human populations may move to preserve their environmental temperature. The distances they must travel to do this depends on how much cooler nearby surfaces temperatures are. Because large-scale atmospheric dynamics constrain surface temperatures to be nearly uniform near the equator, these displacements can grow to extreme distances in the tropics, even under relatively mild warming scenarios. Here we show that in order to preserve their annual mean temperatures, tropical populations would have to travel distances greater than 1000 km over less than a century if global mean temperature rises by 2 °C over the same period. The disproportionately rapid evacuation of the tropics under such a scenario would cause migrants to concentrate in tropical margins and the subtropics, where population densities would increase 300% or more. These results may have critical consequences for ecosystem and human wellbeing in tropical contexts where alternatives to geographic displacement are limited.

  17. Food and fitness: associations between crop yields and life-history traits in a longitudinally monitored pre-industrial human population.

    PubMed

    Hayward, Adam D; Holopainen, Jari; Pettay, Jenni E; Lummaa, Virpi

    2012-10-22

    Severe food shortage is associated with increased mortality and reduced reproductive success in contemporary and historical human populations. Studies of wild animal populations have shown that subtle variation in environmental conditions can influence patterns of mortality, fecundity and natural selection, but the fitness implications of such subtle variation on human populations are unclear. Here, we use longitudinal data on local grain production, births, marriages and mortality so as to assess the impact of crop yield variation on individual age-specific mortality and fecundity in two pre-industrial Finnish populations. Although crop yields and fitness traits showed profound year-to-year variation across the 70-year study period, associations between crop yields and mortality or fecundity were generally weak. However, post-reproductive individuals of both sexes, and individuals of lower socio-economic status experienced higher mortality when crop yields were low. This is the first longitudinal, individual-based study of the associations between environmental variation and fitness traits in pre-industrial humans, which emphasizes the importance of a portfolio of mechanisms for coping with low food availability in such populations. The results are consistent with evolutionary ecological predictions that natural selection for resilience to food shortage is likely to weaken with age and be most severe on those with the fewest resources.

  18. The role of microbiota in retinal disease

    USDA-ARS?s Scientific Manuscript database

    The ten years since the first publications on the human microbiome project have brought enormous attention and insight into the role of the human microbiome in health and disease. Connections between populations of microbiota and ocular disease are now being established, and increased accessibility ...

  19. Population specific biomarkers of human aging: a big data study using South Korean, Canadian and Eastern European patient populations.

    PubMed

    Mamoshina, Polina; Kochetov, Kirill; Putin, Evgeny; Cortese, Franco; Aliper, Alexander; Lee, Won-Suk; Ahn, Sung-Min; Uhn, Lee; Skjodt, Neil; Kovalchuk, Olga; Scheibye-Knudsen, Morten; Zhavoronkov, Alex

    2018-01-11

    Accurate and physiologically meaningful biomarkers for human aging are key to assessing anti-aging therapies. Given ethnic differences in health, diet, lifestyle, behaviour, environmental exposures and even average rate of biological aging, it stands to reason that aging clocks trained on datasets obtained from specific ethnic populations are more likely to account for these potential confounding factors, resulting in an enhanced capacity to predict chronological age and quantify biological age. Here we present a deep learning-based hematological aging clock modeled using the large combined dataset of Canadian, South Korean and Eastern European population blood samples that show increased predictive accuracy in individual populations compared to population-specific hematologic aging clocks. The performance of models was also evaluated on publicly-available samples of the American population from the National Health and Nutrition Examination Survey (NHANES). In addition, we explored the association between age predicted by both population-specific and combined hematological clocks and all-cause mortality. Overall, this study suggests a) the population-specificity of aging patterns and b) hematologic clocks predicts all-cause mortality. Proposed models added to the freely available Aging.AI system allowing improved ability to assess human aging. © The Author(s) 2018. Published by Oxford University Press on behalf of The Gerontological Society of America.

  20. Low levels of genetic divergence across geographically and linguistically diverse populations from India.

    PubMed

    Rosenberg, Noah A; Mahajan, Saurabh; Gonzalez-Quevedo, Catalina; Blum, Michael G B; Nino-Rosales, Laura; Ninis, Vasiliki; Das, Parimal; Hegde, Madhuri; Molinari, Laura; Zapata, Gladys; Weber, James L; Belmont, John W; Patel, Pragna I

    2006-12-01

    Ongoing modernization in India has elevated the prevalence of many complex genetic diseases associated with a western lifestyle and diet to near-epidemic proportions. However, although India comprises more than one sixth of the world's human population, it has largely been omitted from genomic surveys that provide the backdrop for association studies of genetic disease. Here, by genotyping India-born individuals sampled in the United States, we carry out an extensive study of Indian genetic variation. We analyze 1,200 genome-wide polymorphisms in 432 individuals from 15 Indian populations. We find that populations from India, and populations from South Asia more generally, constitute one of the major human subgroups with increased similarity of genetic ancestry. However, only a relatively small amount of genetic differentiation exists among the Indian populations. Although caution is warranted due to the fact that United States-sampled Indian populations do not represent a random sample from India, these results suggest that the frequencies of many genetic variants are distinctive in India compared to other parts of the world and that the effects of population heterogeneity on the production of false positives in association studies may be smaller in Indians (and particularly in Indian-Americans) than might be expected for such a geographically and linguistically diverse subset of the human population.

  1. Trends in the use and cost of human and analogue insulins in a Colombian population, 2011-2015.

    PubMed

    Torres, D R; Portilla, A; Machado-Duque, M E; Machado-Alba, J E

    2017-12-01

    Diabetes mellitus is a common disease among the general population and imposes considerable costs on health care systems. Insulin is used to treat type 1 diabetes mellitus and as an adjuvant to oral agents in advanced stages of type 2 diabetes mellitus. The objective was to describe the trends in use and cost of human and analogue insulins for Colombian patients. Descriptive retrospective analysis of prescriptions of human and analogue insulins on a monthly basis for the period from July 1, 2011 to February 2, 2015. Information was collected for the database population of two insurance companies. Frequencies and proportions were calculated; estimated economic impact was expressed as net cost and cost per thousand inhabitants per day. During the observation period, there was continuous growth in use of insulin, mainly in analogue forms (34.0% growth). At the start of the study, 10.4% of subjects were using an analogue insulin; this figure was 62.6% at the end of the study. In 2012, the average cost per 1000 inhabitants/day was US$1.7 for analogue and US$0.8 for human insulins. At the end of the observation period these costs had risen to US$9.2 for analogue (441.1% increase) and fallen to US$0.5 for human insulin (58.3% decrease). There has been an increase in the unit cost and frequency of use of insulin analogues for anti-diabetic therapy in Colombian patients. Moreover, there is controversy over whether insulin analogues are a more cost-effective treatment than human insulins for the general diabetic population. Copyright © 2017 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  2. Connectivity of Tiger (Panthera tigris) Populations in the Human-Influenced Forest Mosaic of Central India

    PubMed Central

    Joshi, Aditya; Vaidyanathan, Srinivas; Mondol, Samrat; Edgaonkar, Advait; Ramakrishnan, Uma

    2013-01-01

    Today, most wild tigers live in small, isolated Protected Areas within human dominated landscapes in the Indian subcontinent. Future survival of tigers depends on increasing local population size, as well as maintaining connectivity between populations. While significant conservation effort has been invested in increasing tiger population size, few initiatives have focused on landscape-level connectivity and on understanding the effect different landscape elements have on maintaining connectivity. We combined individual-based genetic and landscape ecology approaches to address this issue in six protected areas with varying tiger densities and separation in the Central Indian tiger landscape. We non-invasively sampled 55 tigers from different protected areas within this landscape. Maximum-likelihood and Bayesian genetic assignment tests indicate long-range tiger dispersal (on the order of 650 km) between protected areas. Further geo-spatial analyses revealed that tiger connectivity was affected by landscape elements such as human settlements, road density and host-population tiger density, but not by distance between populations. Our results elucidate the importance of landscape and habitat viability outside and between protected areas and provide a quantitative approach to test functionality of tiger corridors. We suggest future management strategies aim to minimize urban expansion between protected areas to maximize tiger connectivity. Achieving this goal in the context of ongoing urbanization and need to sustain current economic growth exerts enormous pressure on the remaining tiger habitats and emerges as a big challenge to conserve wild tigers in the Indian subcontinent. PMID:24223132

  3. Connectivity of tiger (Panthera tigris) populations in the human-influenced forest mosaic of Central India.

    PubMed

    Joshi, Aditya; Vaidyanathan, Srinivas; Mondol, Samrat; Edgaonkar, Advait; Ramakrishnan, Uma

    2013-01-01

    Today, most wild tigers live in small, isolated Protected Areas within human dominated landscapes in the Indian subcontinent. Future survival of tigers depends on increasing local population size, as well as maintaining connectivity between populations. While significant conservation effort has been invested in increasing tiger population size, few initiatives have focused on landscape-level connectivity and on understanding the effect different landscape elements have on maintaining connectivity. We combined individual-based genetic and landscape ecology approaches to address this issue in six protected areas with varying tiger densities and separation in the Central Indian tiger landscape. We non-invasively sampled 55 tigers from different protected areas within this landscape. Maximum-likelihood and Bayesian genetic assignment tests indicate long-range tiger dispersal (on the order of 650 km) between protected areas. Further geo-spatial analyses revealed that tiger connectivity was affected by landscape elements such as human settlements, road density and host-population tiger density, but not by distance between populations. Our results elucidate the importance of landscape and habitat viability outside and between protected areas and provide a quantitative approach to test functionality of tiger corridors. We suggest future management strategies aim to minimize urban expansion between protected areas to maximize tiger connectivity. Achieving this goal in the context of ongoing urbanization and need to sustain current economic growth exerts enormous pressure on the remaining tiger habitats and emerges as a big challenge to conserve wild tigers in the Indian subcontinent.

  4. Dog ownership and all-cause mortality in a population cohort in Norway: The HUNT study.

    PubMed

    Torske, Magnhild Oust; Krokstad, Steinar; Stamatakis, Emmanuel; Bauman, Adrian

    2017-01-01

    There has been increased interest in human-animal interactions and their possible effects on human health. Some of this research has focused on human physical activity levels, mediated through increased dog walking. Much of the reported research has been cross sectional, and very few epidemiological studies have examined the association between dog ownership and mortality in populations. We used data from the Norwegian county population-based Nord-Trøndelag HUNT Study (HUNT2, 1995-1997). Cox proportional hazards models were fitted to analyse the relationship between dog ownership and all-cause mortality. The median follow-up time was 18.5 years and the maximum follow-up time was 19.7 years. In this population, dog owners were no more physically active than non-dog owners, both groups reporting a total of just over 3 hours/week of light and vigorous activity. Dog owners (n = 25,031, with 1,587 deaths during follow-up; 504,017 person-years of time at risk) had virtually the same hazard of dying as non-dog owners (Hazard ratio 1.00, 95% CI 0.91-1.09). We found no evidence for an association between the presence of a dog in the household and all-cause mortality or physical activity levels in this Norwegian population. Further epidemiological research is needed to clarify this relationship, as methodological limitations and an active Norwegian population sample means that generalizable evidence is not yet clear on dog ownership and mortality.

  5. Trends in mortality and biological stress in a medieval polish urban population.

    PubMed

    Betsinger, Tracy K; DeWitte, Sharon

    2017-12-01

    Urbanization in pre-modern populations may have had a variety of consequences related to population crowding. However, research on the effects of urbanization have provided inconsistent results regarding the biological impact of this transition on human populations. The purpose of this study is to test the hypothesis that urbanization caused an increase in overall biological stress in a medieval (10th-13th centuries AD) Polish population. A human skeletal sample (n=164) was examined for the presence of porotic hyperostosis, cribra orbitalia, linear enamel hypoplasia, periosteal reaction, and specific infectious diseases. Prevalence rates were compared among three temporal samples: initial urbanization, early urbanization, and later urbanization. Results indicate no significant trends for any of the pathological conditions. Cox proportional hazards analyses, however, revealed a significant increase in the risk of death over time, which supports the hypothesis. These results reflect the necessity of using multiple analyses to address bioarchaeological questions. The lack of significant results from skeletal indicators may be due to an earlier urbanization trend in the population. This study illustrates that the association of urbanization with elevated biological stress is complicated and dependent on various factors, including culture and time period. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. The challenges of human population ageing

    PubMed Central

    Sander, Miriam; Oxlund, Bjarke; Jespersen, Astrid; Krasnik, Allan; Mortensen, Erik Lykke; Westendorp, Rudi Gerardus Johannes; Rasmussen, Lene Juel

    2015-01-01

    The 20th century saw an unprecedented increase in average human lifespan as well as a rapid decline in human fertility in many countries of the world. The accompanying worldwide change in demographics of human populations is linked to unanticipated and unprecedented economic, cultural, medical, social, public health and public policy challenges, whose full implications on a societal level are only just beginning to be fully appreciated. Some of these implications are discussed in this commentary, an outcome of Cultures of Health and Ageing, a conference co-sponsored by the University of Copenhagen (UCPH) and the Center for Healthy Ageing at UCPH, which took place on 20–21 June 2014 in Copenhagen, Denmark. Questions discussed here include the following: what is driving age-structural change in human populations? how can we create ‘age-friendly’ societies and promote ‘ageing-in-community’? what tools will effectively promote social engagement and prevent social detachment among older individuals? is there a risk that further extension of human lifespan would be a greater burden to the individual and to society than is warranted by the potential benefit of longer life? PMID:25452294

  7. Evaluation of a smartphone human activity recognition application with able-bodied and stroke participants.

    PubMed

    Capela, N A; Lemaire, E D; Baddour, N; Rudolf, M; Goljar, N; Burger, H

    2016-01-20

    Mobile health monitoring using wearable sensors is a growing area of interest. As the world's population ages and locomotor capabilities decrease, the ability to report on a person's mobility activities outside a hospital setting becomes a valuable tool for clinical decision-making and evaluating healthcare interventions. Smartphones are omnipresent in society and offer convenient and suitable sensors for mobility monitoring applications. To enhance our understanding of human activity recognition (HAR) system performance for able-bodied and populations with gait deviations, this research evaluated a custom smartphone-based HAR classifier on fifteen able-bodied participants and fifteen participants who suffered a stroke. Participants performed a consecutive series of mobility tasks and daily living activities while wearing a BlackBerry Z10 smartphone on their waist to collect accelerometer and gyroscope data. Five features were derived from the sensor data and used to classify participant activities (decision tree). Sensitivity, specificity and F-scores were calculated to evaluate HAR classifier performance. The classifier performed well for both populations when differentiating mobile from immobile states (F-score > 94 %). As activity recognition complexity increased, HAR system sensitivity and specificity decreased for the stroke population, particularly when using information derived from participant posture to make classification decisions. Human activity recognition using a smartphone based system can be accomplished for both able-bodied and stroke populations; however, an increase in activity classification complexity leads to a decrease in HAR performance with a stroke population. The study results can be used to guide smartphone HAR system development for populations with differing movement characteristics.

  8. The consequences of poaching and anthropogenic change for forest elephants.

    PubMed

    Breuer, Thomas; Maisels, Fiona; Fishlock, Vicki

    2016-10-01

    Poaching has devastated forest elephant populations (Loxodonta cyclotis), and their habitat is dramatically changing. The long-term effects of poaching and other anthropogenic threats have been well studied in savannah elephants (Loxodonta africana), but the impacts of these changes for Central Africa's forest elephants have not been discussed. We examined potential repercussions of these threats and the related consequences for forest elephants in Central Africa by summarizing the lessons learned from savannah elephants and small forest elephant populations in West Africa. Forest elephant social organization is less known than the social organization of savannah elephants, but the close evolutionary history of these species suggests that they will respond to anthropogenic threats in broadly similar ways. The loss of older, experienced individuals in an elephant population disrupts ecological, social, and population parameters. Severe reduction of elephant abundance within Central Africa's forests can alter plant communities and ecosystem functions. Poaching, habitat alterations, and human population increase are probably compressing forest elephants into protected areas and increasing human-elephant conflict, which negatively affects their conservation. We encourage conservationists to look beyond documenting forest elephant population decline and address the causes of these declines when developing conversation strategies. We suggest assessing the effectiveness of the existing protected-area networks for landscape connectivity in light of current industrial and infrastructure development. Longitudinal assessments of the effects of landscape changes on forest elephant sociality and behavior are also needed. Finally, lessons learned from West African elephant population loss and habitat fragmentation should be used to inform strategies for land-use planning and managing human-elephant interactions. © 2016 Society for Conservation Biology.

  9. Type 2 Diabetes Risk Alleles Demonstrate Extreme Directional Differentiation among Human Populations, Compared to Other Diseases

    PubMed Central

    Chen, Rong; Corona, Erik; Sikora, Martin; Dudley, Joel T.; Morgan, Alex A.; Moreno-Estrada, Andres; Nilsen, Geoffrey B.; Ruau, David; Lincoln, Stephen E.; Bustamante, Carlos D.; Butte, Atul J.

    2012-01-01

    Many disease-susceptible SNPs exhibit significant disparity in ancestral and derived allele frequencies across worldwide populations. While previous studies have examined population differentiation of alleles at specific SNPs, global ethnic patterns of ensembles of disease risk alleles across human diseases are unexamined. To examine these patterns, we manually curated ethnic disease association data from 5,065 papers on human genetic studies representing 1,495 diseases, recording the precise risk alleles and their measured population frequencies and estimated effect sizes. We systematically compared the population frequencies of cross-ethnic risk alleles for each disease across 1,397 individuals from 11 HapMap populations, 1,064 individuals from 53 HGDP populations, and 49 individuals with whole-genome sequences from 10 populations. Type 2 diabetes (T2D) demonstrated extreme directional differentiation of risk allele frequencies across human populations, compared with null distributions of European-frequency matched control genomic alleles and risk alleles for other diseases. Most T2D risk alleles share a consistent pattern of decreasing frequencies along human migration into East Asia. Furthermore, we show that these patterns contribute to disparities in predicted genetic risk across 1,397 HapMap individuals, T2D genetic risk being consistently higher for individuals in the African populations and lower in the Asian populations, irrespective of the ethnicity considered in the initial discovery of risk alleles. We observed a similar pattern in the distribution of T2D Genetic Risk Scores, which are associated with an increased risk of developing diabetes in the Diabetes Prevention Program cohort, for the same individuals. This disparity may be attributable to the promotion of energy storage and usage appropriate to environments and inconsistent energy intake. Our results indicate that the differential frequencies of T2D risk alleles may contribute to the observed disparity in T2D incidence rates across ethnic populations. PMID:22511877

  10. Can Education for Sustainable Development Address Challenges in the Arab Region? Examining Business Students' Attitudes and Competences on Education for Sustainable Development: A Case Study

    ERIC Educational Resources Information Center

    Kanbar, Nancy

    2012-01-01

    The population growth together with the unsustainable consumption pattern is putting increasing stress on the planet's natural resources. The increasing realisation that humans are harming the environment is taking the form of a global movement intended to change behaviour towards sustainability, now recognised as a framework that links humans to…

  11. Repeatability and degree of territorial aggression differs among urban and rural great tits (Parus major).

    PubMed

    Hardman, Samuel I; Dalesman, Sarah

    2018-03-22

    Animals in urban habitats face many novel selection pressures such as increased human population densities and human disturbance. This is predicted to favour bolder and more aggressive individuals together with greater flexibility in behaviour. Previous work has focussed primarily on studying these traits in captive birds and has shown increased aggression and reduced consistency between traits (behavioural syndromes) in birds from urban populations. However, personality (consistency within a behavioural trait) has not been well studied in the wild. Here we tested whether urban free-living male great tits show greater territorial aggression than rural counterparts. We also tested predictions that both behavioural syndromes and personality would show lower consistency in urban populations. We found that urban populations were more aggressive than rural populations and urban birds appeared to show lower levels of individual behavioural repeatability (personality) as predicted. However, we found no effect of urbanisation on behavioural syndromes (correlations between multiple behavioural traits). Our results indicate that urban environments may favour individuals which exhibit increased territorial aggression and greater within-trait flexibility which may be essential to success in holding urban territories. Determining how urban environments impact key fitness traits will be important in predicting how animals cope with ongoing urbanisation.

  12. Temporal dynamics of Puumala hantavirus infection in cyclic populations of bank voles.

    PubMed

    Voutilainen, Liina; Kallio, Eva R; Niemimaa, Jukka; Vapalahti, Olli; Henttonen, Heikki

    2016-02-18

    Understanding the dynamics of zoonotic pathogens in their reservoir host populations is a prerequisite for predicting and preventing human disease epidemics. The human infection risk of Puumala hantavirus (PUUV) is highest in northern Europe, where populations of the rodent host (bank vole, Myodes glareolus) undergo cyclic fluctuations. We conducted a 7-year capture-mark-recapture study to monitor seasonal and multiannual patterns of the PUUV infection rate in bank vole populations exhibiting a 3-year density cycle. Infected bank voles were most abundant in mid-winter months during years of increasing or peak host density. Prevalence of PUUV infection in bank voles exhibited a regular, seasonal pattern reflecting the annual population turnover and accumulation of infections within each year cohort. In autumn, the PUUV transmission rate tracked increasing host abundance, suggesting a density-dependent transmission. However, prevalence of PUUV infection was similar during the increase and peak years of the density cycle despite a twofold difference in host density. This may result from the high proportion of individuals carrying maternal antibodies constraining transmission during the cycle peak years. Our exceptionally intensive and long-term dataset provides a solid basis on which to develop models to predict the dynamic public health threat posed by PUUV in northern Europe.

  13. Climate change, human health, and epidemiological transition.

    PubMed

    Barrett, Bruce; Charles, Joel W; Temte, Jonathan L

    2015-01-01

    The health of populations depends on the availability of clean air, water, food, and sanitation, exposure to pathogens, toxins and environmental hazards, and numerous genetic, behavioral and social factors. For many thousands of years, human life expectancy was low, and population growth was slow. The development of technology-based civilizations facilitated what Abdel Omran called "epidemiological transition," with increasing life expectancy and rapid population growth. To a large extent, the spectacular growth of human populations during the past two centuries was made possible by the energy extracted from fossil fuels. We have now learned, however, that greenhouse gases from fossil fuel combustion are warming the planet's surface, causing changes in oceanic and atmospheric systems, and disrupting weather and hydrological patterns. Climate change poses unprecedented threats to human health by impacts on food and water security, heat waves and droughts, violent storms, infectious disease, and rising sea levels. Whether or not humanity can reduce greenhouse gas emissions quickly enough to slow climate change to a rate that will allow societies to successfully adapt is not yet known. This essay reviews the current state of relevant knowledge, and points in a few directions that those interested in human health may wish to consider. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Older age becomes common late in human evolution

    PubMed Central

    Caspari, Rachel; Lee, Sang-Hee

    2004-01-01

    Increased longevity, expressed as number of individuals surviving to older adulthood, represents one of the ways the human life history pattern differs from other primates. We believe it is a critical demographic factor in the development of human culture. Here, we examine when changes in longevity occurred by assessing the ratio of older to younger adults in four hominid dental samples from successive time periods, and by determining the significance of differences in these ratios. Younger and older adult status is assessed by wear seriation of each sample. Whereas there is significant increased longevity between all groups, indicating a trend of increased adult survivorship over the course of human evolution, there is a dramatic increase in longevity in the modern humans of the Early Upper Paleolithic. We believe that this great increase contributed to population expansions and cultural innovations associated with modernity. PMID:15252198

  15. How Nature-Based Tourism Might Increase Prey Vulnerability to Predators.

    PubMed

    Geffroy, Benjamin; Samia, Diogo S M; Bessa, Eduardo; Blumstein, Daniel T

    2015-12-01

    Tourism can be deleterious for wildlife because it triggers behavioral changes in individuals with cascading effects on populations and communities. Among these behavioral changes, animals around humans often reduce their fearfulness and antipredator responses towards humans. A straightforward prediction is that habituation to humans associated with tourism would negatively influence reaction to predators. This could happen indirectly, where human presence decreases the number of natural predators and thus prey become less wary, or directly, where human-habituated individuals become bolder and thus more vulnerable to predation. Building on ideas from the study of traits associated with domestication and urbanization, we develop a framework to understand how behavioral changes associated with nature-based tourism can impact individual fitness, and thus the demographic trajectory of a population. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Genetic evidence and the modern human origins debate.

    PubMed

    Relethford, J H

    2008-06-01

    A continued debate in anthropology concerns the evolutionary origin of 'anatomically modern humans' (Homo sapiens sapiens). Different models have been proposed to examine the related questions of (1) where and when anatomically modern humans first appeared and (2) the genetic and evolutionary relationship between modern humans and earlier human populations. Genetic data have been increasingly used to address these questions. Genetic data on living human populations have been used to reconstruct the evolutionary history of the human species by considering how global patterns of human variation could be produced given different evolutionary scenarios. Of particular interest are gene trees that reconstruct the time and place of the most recent common ancestor of humanity for a given haplotype and the analysis of regional differences in genetic diversity. Ancient DNA has also allowed a direct assessment of genetic variation in European Neandertals. Together with the fossil record, genetic data provide insight into the origin of modern humans. The evidence points to an African origin of modern humans dating back to 200,000 years followed by later expansions of moderns out of Africa across the Old World. What is less clear is what happened when these early modern humans met preexisting 'archaic human' populations outside of Africa. At present, it is difficult to distinguish between a model of total genetic replacement and a model that includes some degree of genetic mixture.

  17. Normobaric hypoxic conditioning to maximize weight loss and ameliorate cardio-metabolic health in obese populations: a systematic review.

    PubMed

    Hobbins, L; Hunter, S; Gaoua, N; Girard, O

    2017-09-01

    Normobaric hypoxic conditioning (HC) is defined as exposure to systemic and/or local hypoxia at rest (passive) or combined with exercise training (active). HC has been previously used by healthy and athletic populations to enhance their physical capacity and improve performance in the lead up to competition. Recently, HC has also been applied acutely (single exposure) and chronically (repeated exposure over several weeks) to overweight and obese populations with the intention of managing and potentially increasing cardio-metabolic health and weight loss. At present, it is unclear what the cardio-metabolic health and weight loss responses of obese populations are in response to passive and active HC. Exploration of potential benefits of exposure to both passive and active HC may provide pivotal findings for improving health and well being in these individuals. A systematic literature search for articles published between 2000 and 2017 was carried out. Studies investigating the effects of normobaric HC as a novel therapeutic approach to elicit improvements in the cardio-metabolic health and weight loss of obese populations were included. Studies investigated passive ( n = 7; 5 animals, 2 humans), active ( n = 4; all humans) and a combination of passive and active ( n = 4; 3 animals, 1 human) HC to an inspired oxygen fraction ([Formula: see text]) between 4.8 and 15.0%, ranging between a single session and daily sessions per week, lasting from 5 days up to 8 mo. Passive HC led to reduced insulin concentrations (-37 to -22%) in obese animals and increased energy expenditure (+12 to +16%) in obese humans, whereas active HC lead to reductions in body weight (-4 to -2%) in obese animals and humans, and blood pressure (-8 to -3%) in obese humans compared with a matched workload in normoxic conditions. Inconclusive findings, however, exist in determining the impact of acute and chronic HC on markers such as triglycerides, cholesterol levels, and fitness capacity. Importantly, most of the studies that included animal models involved exposure to severe levels of hypoxia ([Formula: see text] = 5.0%; simulated altitude >10,000 m) that are not suitable for human populations. Overall, normobaric HC demonstrated observable positive findings in relation to insulin and energy expenditure (passive), and body weight and blood pressure (active), which may improve the cardio-metabolic health and body weight management of obese populations. However, further evidence on responses of circulating biomarkers to both passive and active HC in humans is warranted. Copyright © 2017 the American Physiological Society.

  18. How good are indirect tests at detecting recombination in human mtDNA?

    PubMed

    White, Daniel James; Bryant, David; Gemmell, Neil John

    2013-07-08

    Empirical proof of human mitochondrial DNA (mtDNA) recombination in somatic tissues was obtained in 2004; however, a lack of irrefutable evidence exists for recombination in human mtDNA at the population level. Our inability to demonstrate convincingly a signal of recombination in population data sets of human mtDNA sequence may be due, in part, to the ineffectiveness of current indirect tests. Previously, we tested some well-established indirect tests of recombination (linkage disequilibrium vs. distance using D' and r(2), Homoplasy Test, Pairwise Homoplasy Index, Neighborhood Similarity Score, and Max χ(2)) on sequence data derived from the only empirically confirmed case of human mtDNA recombination thus far and demonstrated that some methods were unable to detect recombination. Here, we assess the performance of these six well-established tests and explore what characteristics specific to human mtDNA sequence may affect their efficacy by simulating sequence under various parameters with levels of recombination (ρ) that vary around an empirically derived estimate for human mtDNA (population parameter ρ = 5.492). No test performed infallibly under any of our scenarios, and error rates varied across tests, whereas detection rates increased substantially with ρ values > 5.492. Under a model of evolution that incorporates parameters specific to human mtDNA, including rate heterogeneity, population expansion, and ρ = 5.492, successful detection rates are limited to a range of 7-70% across tests with an acceptable level of false-positive results: the neighborhood similarity score incompatibility test performed best overall under these parameters. Population growth seems to have the greatest impact on recombination detection probabilities across all models tested, likely due to its impact on sequence diversity. The implications of our findings on our current understanding of mtDNA recombination in humans are discussed.

  19. How Good Are Indirect Tests at Detecting Recombination in Human mtDNA?

    PubMed Central

    White, Daniel James; Bryant, David; Gemmell, Neil John

    2013-01-01

    Empirical proof of human mitochondrial DNA (mtDNA) recombination in somatic tissues was obtained in 2004; however, a lack of irrefutable evidence exists for recombination in human mtDNA at the population level. Our inability to demonstrate convincingly a signal of recombination in population data sets of human mtDNA sequence may be due, in part, to the ineffectiveness of current indirect tests. Previously, we tested some well-established indirect tests of recombination (linkage disequilibrium vs. distance using D′ and r2, Homoplasy Test, Pairwise Homoplasy Index, Neighborhood Similarity Score, and Max χ2) on sequence data derived from the only empirically confirmed case of human mtDNA recombination thus far and demonstrated that some methods were unable to detect recombination. Here, we assess the performance of these six well-established tests and explore what characteristics specific to human mtDNA sequence may affect their efficacy by simulating sequence under various parameters with levels of recombination (ρ) that vary around an empirically derived estimate for human mtDNA (population parameter ρ = 5.492). No test performed infallibly under any of our scenarios, and error rates varied across tests, whereas detection rates increased substantially with ρ values > 5.492. Under a model of evolution that incorporates parameters specific to human mtDNA, including rate heterogeneity, population expansion, and ρ = 5.492, successful detection rates are limited to a range of 7−70% across tests with an acceptable level of false-positive results: the neighborhood similarity score incompatibility test performed best overall under these parameters. Population growth seems to have the greatest impact on recombination detection probabilities across all models tested, likely due to its impact on sequence diversity. The implications of our findings on our current understanding of mtDNA recombination in humans are discussed. PMID:23665874

  20. Phage and MLVA typing of Salmonella enteritidis isolated from layers and humans in Belgium from 2000-2010, a period in which vaccination of laying hens was introduced.

    PubMed

    Dewaele, I; Heyndrickx, M; Rasschaert, G; Bertrand, S; Wildemauwe, C; Wattiau, P; Imberechts, H; Herman, L; Ducatelle, R; Van Weyenberg, S; De Reu, K

    2014-09-01

    The aim of the study was to characterize isolates of Salmonella enterica serovar Enteritidis (S. Enteritidis) obtained from humans and layer farms in Belgium collected during 2000-2010. Three periods were compared, namely (i) before implementation of vaccination (2000-2004), (ii) during voluntary vaccination (2005-2006) and (iii) during implementation of the national control program (NCP) for Salmonella including mandatory vaccination against S. Enteritidis (2007-2010). The characteristics compared across time periods were distributions of phage type and multiple-locus variable number tandem-repeat assay (MLVA). While PT4 and PT21 were predominantly isolated in Belgium in layers and humans before 2007, a significant reduction of those PTs was observed in both populations in the period 2007-2010. The relative proportion of PT4b, PT21c and PT6c was found to have increased considerably in the layer population since 2007. In the human population, PT8, PT1 and the group of 'other' PTs were more frequently isolated compared to the previous periods. When comparing the proportion of the predominant MLVA types Q2 and U2, no significant difference was found between the layer and human population in the three periods and between periods within each category (layer and human). A significant difference in isolate distribution among MLVA clusters I and II was found between human and layer isolates recovered during Period 3 and in the human population between Period 1 and 3. Results suggest that the association between S. Enteritidis in layers and the occurrence of the pathogen in humans changed since implementation of the NCP in 2007. © 2013 Blackwell Verlag GmbH.

  1. Fishery-independent data reveal negative effect of human population density on Caribbean predatory fish communities.

    PubMed

    Stallings, Christopher D

    2009-01-01

    Understanding the current status of predatory fish communities, and the effects fishing has on them, is vitally important information for management. However, data are often insufficient at region-wide scales to assess the effects of extraction in coral reef ecosystems of developing nations. Here, I overcome this difficulty by using a publicly accessible, fisheries-independent database to provide a broad scale, comprehensive analysis of human impacts on predatory reef fish communities across the greater Caribbean region. Specifically, this study analyzed presence and diversity of predatory reef fishes over a gradient of human population density. Across the region, as human population density increases, presence of large-bodied fishes declines, and fish communities become dominated by a few smaller-bodied species. Complete disappearance of several large-bodied fishes indicates ecological and local extinctions have occurred in some densely populated areas. These findings fill a fundamentally important gap in our knowledge of the ecosystem effects of artisanal fisheries in developing nations, and provide support for multiple approaches to data collection where they are commonly unavailable.

  2. Fishery-Independent Data Reveal Negative Effect of Human Population Density on Caribbean Predatory Fish Communities

    PubMed Central

    Stallings, Christopher D.

    2009-01-01

    Background Understanding the current status of predatory fish communities, and the effects fishing has on them, is vitally important information for management. However, data are often insufficient at region-wide scales to assess the effects of extraction in coral reef ecosystems of developing nations. Methodology/Principal Findings Here, I overcome this difficulty by using a publicly accessible, fisheries-independent database to provide a broad scale, comprehensive analysis of human impacts on predatory reef fish communities across the greater Caribbean region. Specifically, this study analyzed presence and diversity of predatory reef fishes over a gradient of human population density. Across the region, as human population density increases, presence of large-bodied fishes declines, and fish communities become dominated by a few smaller-bodied species. Conclusions/Significance Complete disappearance of several large-bodied fishes indicates ecological and local extinctions have occurred in some densely populated areas. These findings fill a fundamentally important gap in our knowledge of the ecosystem effects of artisanal fisheries in developing nations, and provide support for multiple approaches to data collection where they are commonly unavailable. PMID:19421312

  3. Weaning age in an expanding population: stable carbon and nitrogen isotope analysis of infant feeding practices in the Okhotsk culture (5th-13th centuries AD) in Northern Japan.

    PubMed

    Tsutaya, Takumi; Ishida, Hajime; Yoneda, Minoru

    2015-08-01

    The Okhotsk people were sedentary hunter-gatherer-fishers who lived and prospered in Sakhalin, Hokkaido, and the Kurile Islands during the 5th to 13th centuries AD. They expanded rapidly along the northeastern coast of Hokkaido. We reconstructed infant feeding practices of the Moyoro population of the Okhotsk culture in eastern Hokkaido, Japan. Stable isotope ratios in 58 subadult human skeletons were measured. The results suggest that complementary foods with a relatively low carbon isotope ratio were consumed during and after weaning, as observed in ethnographic descriptions of northern human populations such as the Ainu and isotopically suggested in ancient northern hunter-gatherer-fisher populations. Nitrogen isotope ratios of subadults showed that the age at the end of weaning in the Moyoro population was 1.8 (1.4-2.2 in 95% credible interval) years, which is earlier than that in other northern hunter-gatherer-fisher populations. Because weaning age is one of the most important determinants of fertility, a shorter breastfeeding period suggests increased fertility. Furthermore, better nutrition would further promote the population increase, and thus populations of the Okhotsk culture could expand into new regions. These findings are consistent with recent emerging evidence of great contributions of the Okhotsk to the formation of later Ainu populations and culture. © 2015 Wiley Periodicals, Inc.

  4. Characterizing the impact of projected changes in climate and air quality on human exposures to ozone.

    PubMed

    Dionisio, Kathie L; Nolte, Christopher G; Spero, Tanya L; Graham, Stephen; Caraway, Nina; Foley, Kristen M; Isaacs, Kristin K

    2017-05-01

    The impact of climate change on human and environmental health is of critical concern. Population exposures to air pollutants both indoors and outdoors are influenced by a wide range of air quality, meteorological, behavioral, and housing-related factors, many of which are also impacted by climate change. An integrated methodology for modeling changes in human exposures to tropospheric ozone (O 3 ) owing to potential future changes in climate and demographics was implemented by linking existing modeling tools for climate, weather, air quality, population distribution, and human exposure. Human exposure results from the Air Pollutants Exposure Model (APEX) for 12 US cities show differences in daily maximum 8-h (DM8H) exposure patterns and levels by sex, age, and city for all scenarios. When climate is held constant and population demographics are varied, minimal difference in O 3 exposures is predicted even with the most extreme demographic change scenario. In contrast, when population is held constant, we see evidence of substantial changes in O 3 exposure for the most extreme change in climate. Similarly, we see increases in the percentage of the population in each city with at least one O 3 exposure exceedance above 60 p.p.b and 70 p.p.b thresholds for future changes in climate. For these climate and population scenarios, the impact of projected changes in climate and air quality on human exposure to O 3 are much larger than the impacts of changing demographics. These results indicate the potential for future changes in O 3 exposure as a result of changes in climate that could impact human health.

  5. Hypsographic demography: The distribution of human population by altitude

    PubMed Central

    Cohen, Joel E.; Small, Christopher

    1998-01-01

    The global distribution of the human population by elevation is quantified here. As of 1994, an estimated 1.88 × 109 people, or 33.5% of the world’s population, lived within 100 vertical meters of sea level, but only 15.6% of all inhabited land lies below 100 m elevation. The median person lived at an elevation of 194 m above sea level. Numbers of people decreased faster than exponentially with increasing elevation. The integrated population density (IPD, the number of people divided by the land area) within 100 vertical meters of sea level was significantly larger than that of any other range of elevations and represented far more people. A significant percentage of the low-elevation population lived at moderate population densities rather than at the highest densities of central large cities. Assessments of coastal hazards that focus only on large cities may substantially underestimate the number of people who could be affected. PMID:9826643

  6. Competition for dead trees between humans and aye-ayes (Daubentonia madagascariensis) in central eastern Madagascar.

    PubMed

    Miller, Rose T; Raharison, Jean-Luc; Irwin, Mitchell T

    2017-04-01

    The destruction and degradation of forest habitats are major threats to the sustainability of lemur populations in Madagascar. Madagascan landscapes often contain forest fragments that represent refuges for native fauna, while also being used for firewood and timber by local human populations. As undisturbed forest becomes increasingly scarce, understanding resource competition between humans and wildlife in disturbed habitats will be increasingly important. We tested the hypothesis that Malagasy and aye-ayes (Daubentonia madagascariensis) compete for the limited number of dead trees in rainforest fragments at Tsinjoarivo, Madagascar. We surveyed 2.16 ha within five fragments (range 5-228 ha) surrounding human settlements to quantify the density of dead trees and traces of both human and aye-aye activity. Neither aye-aye nor human traces were distributed according to the availability of particular trees species, and aye-ayes and Malagasy apparently preferred several different species. Although overlap was recorded in tree species used, human use tended to be positively correlated with a species' desirability as firewood, while a negative relationship was seen for aye-ayes. Both consumers used trees of similar diameter at breast height, but those used by aye-ayes tended to be older, suggesting that human use might precede usefulness for aye-ayes. Finally, the density of dead trees and aye-aye traces were highest in smaller fragments, but human traces did not vary across fragment size. Although further study is needed to better quantify the aye-aye diet in this region, these data suggest that aye-ayes and local people compete for dead trees, and this competition could constitute a pressure on aye-aye populations.

  7. Human impacts on 20th century fire dynamics and implications for global carbon and water trajectories

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Fang; Lawrence, David M.; Bond-Lamberty, Ben

    Fire is a fundamental Earth system process and the primary ecosystem disturbance on the global scale. It affects carbon and water cycles through changing terrestrial ecosystems, and at the same time, is regulated by weather and climate, vegetation characteristics, and, importantly, human ignitions and suppression (i.e., the direct human effect on fire). Here, we utilize the Community Land Model version 4.5 (CLM4.5) to quantify the impacts of changes in human ignition and suppression on fire dynamics and associated carbon and water cycles. We find that the impact is to significantly reduce the 20th century global burned area by a centurymore » average of 38 Mha/yr and by 103 Mha/yr at the end of the century. Land carbon gain is weakened by 17% over the 20th century, mainly due to increased human deforestation fires and associated escape fires (i.e., degradation fires) in the tropical humid forests, even though the decrease in burned area in many other regions due to human fire suppression acts to increase land carbon gain. The direct human effect on fire weakens the upward trend in global runoff throughout the century by 6% and enhances the upward trend in global evapotranspiration since ~ 1945 by 7%. In addition, the above impacts in densely populated, highly developed (if population density > 0.1 person/km2), or moderately populated and developed regions are of opposite sign to those in other regions. Our study suggests that particular attention should be paid to human deforestation and degradation fires in the tropical humid forests when reconstructing and projecting fire carbon emissions and net atmosphere-land carbon exchange and estimating resultant impacts of direct human effect on fire.« less

  8. Human impacts on 20th century fire dynamics and implications for global carbon and water trajectories

    NASA Astrophysics Data System (ADS)

    Li, Fang; Lawrence, David M.; Bond-Lamberty, Ben

    2018-03-01

    Fire is a fundamental Earth system process and the primary ecosystem disturbance on the global scale. It affects carbon and water cycles through changing terrestrial ecosystems, and at the same time, is regulated by weather and climate, vegetation characteristics, and, importantly, human ignitions and suppression (i.e., the direct human effect on fire). Here, we utilize the Community Land Model version 4.5 (CLM4.5) to quantify the impacts of changes in human ignition and suppression on fire dynamics and associated carbon and water cycles. We find that the impact is to significantly reduce the 20th century global burned area by a century average of 38 Mha/yr and by 103 Mha/yr at the end of the century. Land carbon gain is weakened by 17% over the 20th century, mainly due to increased human deforestation fires and associated escape fires (i.e., degradation fires) in the tropical humid forests, even though the decrease in burned area in many other regions due to human fire suppression acts to increase land carbon gain. The direct human effect on fire weakens the upward trend in global runoff throughout the century by 6% and enhances the upward trend in global evapotranspiration since 1945 by 7%. In addition, the above impacts in densely populated, highly developed (if population density > 0.1 person/km2), or moderately populated and developed regions are of opposite sign to those in other regions. Our study suggests that particular attention should be paid to human deforestation and degradation fires in the tropical humid forests when reconstructing and projecting fire carbon emissions and net atmosphere-land carbon exchange and estimating resultant impacts of direct human effect on fire.

  9. [Effectiveness of the Federal Inspectorate for the Protection of Consumer Rights and Human Welfare in the Novosibirsk Region in 2007 to 2009].

    PubMed

    Mikheev, V N; Ivanova, L K; Iagudin, B I; Turbinskiĭ, V V

    2010-01-01

    A system for monitoring and analyzing the effectiveness and efficiency of the performance of the Board of the Federal Inspectorate for the Protection of Consumer Rights and Human Welfare in the Novosibirsk Region was introduced into its activities to estimate the provision of the Novosibirsk Region's population with sanitary epidemiological wellbeing in 2007-2009. The introduction of monitoring was ascertained to increase the effectiveness of budgetary fund surveillance and spending, by predicting the effectiveness and choice of priority lines of activities, by increasing the quality of budgetary services rendered in the provision of sanitary and epidemiological well-being to the population.

  10. Predictions and Projections of Pine Productivity and Hydrology in Response to Climate Change Across the Southern United States

    Treesearch

    Steven G. McNulty; James M. Vose; Wayne T. Swank

    1998-01-01

    The southeastern United States is one of the most rapidly growing human population regions in continental United States, and as the population increases, the demand for commercial, industrial, and residential water will also increase (USWRC, 1978). Forest species type, stand age, and the climate all influence the amount of water use and yield from these areas (Swank et...

  11. Contrasting X-Linked and Autosomal Diversity across 14 Human Populations

    PubMed Central

    Arbiza, Leonardo; Gottipati, Srikanth; Siepel, Adam; Keinan, Alon

    2014-01-01

    Contrasting the genetic diversity of the human X chromosome (X) and autosomes has facilitated understanding historical differences between males and females and the influence of natural selection. Previous studies based on smaller data sets have left questions regarding how empirical patterns extend to additional populations and which forces can explain them. Here, we address these questions by analyzing the ratio of X-to-autosomal (X/A) nucleotide diversity with the complete genomes of 569 females from 14 populations. Results show that X/A diversity is similar within each continental group but notably lower in European (EUR) and East Asian (ASN) populations than in African (AFR) populations. X/A diversity increases in all populations with increasing distance from genes, highlighting the stronger impact of diversity-reducing selection on X than on the autosomes. However, relative X/A diversity (between two populations) is invariant with distance from genes, suggesting that selection does not drive the relative reduction in X/A diversity in non-Africans (0.842 ± 0.012 for EUR-to-AFR and 0.820 ± 0.032 for ASN-to-AFR comparisons). Finally, an array of models with varying population bottlenecks, expansions, and migration from the latest studies of human demographic history account for about half of the observed reduction in relative X/A diversity from the expected value of 1. They predict values between 0.91 and 0.94 for EUR-to-AFR comparisons and between 0.91 and 0.92 for ASN-to-AFR comparisons. Further reductions can be predicted by more extreme demographic events in excess of those captured by the latest studies but, in the absence of these, also by historical sex-biased demographic events or other processes. PMID:24836452

  12. Characterization of Greater Middle Eastern genetic variation for enhanced disease gene discovery.

    PubMed

    Scott, Eric M; Halees, Anason; Itan, Yuval; Spencer, Emily G; He, Yupeng; Azab, Mostafa Abdellateef; Gabriel, Stacey B; Belkadi, Aziz; Boisson, Bertrand; Abel, Laurent; Clark, Andrew G; Alkuraya, Fowzan S; Casanova, Jean-Laurent; Gleeson, Joseph G

    2016-09-01

    The Greater Middle East (GME) has been a central hub of human migration and population admixture. The tradition of consanguinity, variably practiced in the Persian Gulf region, North Africa, and Central Asia, has resulted in an elevated burden of recessive disease. Here we generated a whole-exome GME variome from 1,111 unrelated subjects. We detected substantial diversity and admixture in continental and subregional populations, corresponding to several ancient founder populations with little evidence of bottlenecks. Measured consanguinity rates were an order of magnitude above those in other sampled populations, and the GME population exhibited an increased burden of runs of homozygosity (ROHs) but showed no evidence for reduced burden of deleterious variation due to classically theorized 'genetic purging'. Applying this database to unsolved recessive conditions in the GME population reduced the number of potential disease-causing variants by four- to sevenfold. These results show variegated genetic architecture in GME populations and support future human genetic discoveries in Mendelian and population genetics.

  13. ASSESSING RISKS TO WILDLIFE POPULATIONS FROM MULTPLE STRESSORS: OVERVIEW OF PROBLEMS AND RESEARCH NEEDS

    EPA Science Inventory

    Wildlife is experiencing increasing pressure from human-induced changes in the landscape. Stressors such as agricultural and urban land use, introduction of invasive and exotic species, alteration of nutrient cycles, direct human disturbance, and toxic chemical exposure directly...

  14. The role of Human Papilloma Virus (HPV) vaccination in the prevention of anal cancer in individuals with Human Immunodeficiency Virus-1 (HIV-1) infection

    PubMed Central

    2013-01-01

    The incidence of anal cancer is increasing in the general population and especially in high-risk groups. A total of 90% of anal cancers are caused by human papilloma virus (HPV) infection of the anal canal. Similar to cervical cancer, anal cancer progresses through a predictable series of premalignant stages before resulting in invasive cancer; this process begins with persistent HPV infection. The HPV vaccine represents a promising strategy to combat the increasing incidence of anal cancer. Human Immunodeficiency Virus (HIV) predisposes people to persistent HPV infection, dysplasia, and subsequent anal cancer. Patients infected with HIV should be targeted for vaccination against HPV. There are difficulties in targeting this population, the most notable being that the optimal age for vaccination is prior to identification with any high-risk groups. Universal vaccination against HPV represents the best strategy to achieve maximum protection against anal cancer in high-risk groups. PMID:24757517

  15. Risk and resilience in the late glacial: A case study from the western Mediterranean

    NASA Astrophysics Data System (ADS)

    Barton, C. Michael; Aura Tortosa, J. Emili; Garcia-Puchol, Oreto; Riel-Salvatore, Julien G.; Gauthier, Nicolas; Vadillo Conesa, Margarita; Pothier Bouchard, Geneviève

    2018-03-01

    The period spanning the Last Glacial Maximum through early Holocene encompasses dramatic and rapid environmental changes that offered both increased risk and new opportunities to human populations of the Mediterranean zone. The regional effects of global climate change varied spatially with latitude, topography, and distance from a shifting coastline; and human adaptations to these changes played out at these regional scales. To better understand the spatial and temporal dynamics of climate change and human social-ecological-technological systems (or SETS) during the transition from full glacial to interglacial, we carried out a meta-analysis of archaeological and paleoenvironmental datasets across the western Mediterranean region. We compiled information on prehistoric technology, land-use, and hunting strategies from 291 archaeological assemblages, recovered from 122 sites extending from southern Spain, through Mediterranean France, to northern and peninsular Italy, as well as 2,386 radiocarbon dates from across this region. We combine these data on human ecological dynamics with paleoenvironmental information derived from global climate models, proxy data, and estimates of coastlines modeled from sea level estimates and digital terrain. The LGM represents an ecologically predictable period for over much of the western Mediterranean, while the remainder of the Pleistocene was increasingly unpredictable, making it a period of increased ecological risk for hunter-gatherers. In response to increasing spatial and temporal uncertainty, hunter-gatherers reorganized different constituents of their SETS, allowing regional populations to adapt to these conditions up to a point. Beyond this threshold, rapid environmental change resulted in significant demographic change in Mediterranean hunter-gatherer populations.

  16. Plague circulation and population genetics of the reservoir Rattus rattus: the influence of topographic relief on the distribution of the disease within the Madagascan focus.

    PubMed

    Brouat, Carine; Rahelinirina, Soanandrasana; Loiseau, Anne; Rahalison, Lila; Rajerison, Minoariso; Laffly, Dominique; Handschumacher, Pascal; Duplantier, Jean-Marc

    2013-01-01

    Landscape may affect the distribution of infectious diseases by influencing the population density and dispersal of hosts and vectors. Plague (Yersinia pestis infection) is a highly virulent, re-emerging disease, the ecology of which has been scarcely studied in Africa. Human seroprevalence data for the major plague focus of Madagascar suggest that plague spreads heterogeneously across the landscape as a function of the relief. Plague is primarily a disease of rodents. We therefore investigated the relationship between disease distribution and the population genetic structure of the black rat, Rattus rattus, the main reservoir of plague in Madagascar. We conducted a comparative study of plague seroprevalence and genetic structure (15 microsatellite markers) in rat populations from four geographic areas differing in topology, each covering about 150-200 km(2) within the Madagascan plague focus. The seroprevalence levels in the rat populations mimicked those previously reported for humans. As expected, rat populations clearly displayed a more marked genetic structure with increasing relief. However, the relationship between seroprevalence data and genetic structure differs between areas, suggesting that plague distribution is not related everywhere to the effective dispersal of rats. Genetic diversity estimates suggested that plague epizootics had only a weak impact on rat population sizes. In the highlands of Madagascar, plague dissemination cannot be accounted for solely by the effective dispersal of the reservoir. Human social activities may also be involved in spreading the disease in rat and human populations.

  17. Elevated Mercury Concentrations in Humans of Madre de Dios, Peru

    PubMed Central

    Ashe, Katy

    2012-01-01

    The enormous increase in practically unregulated mining in Madre de Dios Peru is leading to massive release of liquid elemental mercury to the environment. Rapidly increasing global prices for gold are causing a massive upsurge in artisanal mining in the Peruvian Amazon, considered to be one of the most biodiverse places on the planet. This study identifies the current levels of mercury in the human population, through identifying levels of total mercury in human hair in mining zones of Madre de Dios Department and in the nearby city of Puerto Maldonado. A regression analysis reveals that fish consumption, gender, and location of residence were significant indicators of mercury levels; while duration of residence and age had no significant relationship to mercury levels. Increased fish consumption levels were the strongest indicators of increased total mercury levels across the entire population. The levels of total mercury in hair was significantly (α = 0.05) higher in mining zones, than Puerto Maldonado. In both areas men had significantly higher levels than women, likely due to a difference in metabolism or varying levels of direct involvement in gold mining- a male predominated industry. This is the first study to show the health threat that mercury poses to this region, however further research needs to be done to gain a more refined understanding of the predominant routes of exposure in this population. PMID:22438911

  18. Elevated mercury concentrations in humans of Madre de Dios, Peru.

    PubMed

    Ashe, Katy

    2012-01-01

    The enormous increase in practically unregulated mining in Madre de Dios Peru is leading to massive release of liquid elemental mercury to the environment. Rapidly increasing global prices for gold are causing a massive upsurge in artisanal mining in the Peruvian Amazon, considered to be one of the most biodiverse places on the planet. This study identifies the current levels of mercury in the human population, through identifying levels of total mercury in human hair in mining zones of Madre de Dios Department and in the nearby city of Puerto Maldonado. A regression analysis reveals that fish consumption, gender, and location of residence were significant indicators of mercury levels; while duration of residence and age had no significant relationship to mercury levels. Increased fish consumption levels were the strongest indicators of increased total mercury levels across the entire population. The levels of total mercury in hair was significantly (α = 0.05) higher in mining zones, than Puerto Maldonado. In both areas men had significantly higher levels than women, likely due to a difference in metabolism or varying levels of direct involvement in gold mining- a male predominated industry. This is the first study to show the health threat that mercury poses to this region, however further research needs to be done to gain a more refined understanding of the predominant routes of exposure in this population.

  19. Robust changes in the socio-climate risk over CONUS by mid 21st century

    NASA Astrophysics Data System (ADS)

    Ashfaq, M.; Rastogi, D.; Batibeniz, F.; Alifa, M.; Pagán, B. R.; Bonds, B. W.; Pal, J. S.; Diffenbaugh, N. S.; Preston, B. L.

    2017-12-01

    Using high-resolution near-term ensemble projections of hydro-climatic changes, we investigate impacts of climate change on natural and human systems across the CONUS. Climate projections are based a hybrid downscaling approach where a combination of regional and hydrological models are used to downscales 11 Global Climate Models from the 5th phase of Coupled Model Inter-comparison Project to 4km horizontal grid spacing for 41 years in the historical period (1965-2005) and 41 years in the near-term future period (2010-2050) under Representative Concentration Pathway 8.5. Should emissions continue to rise, climatic changes will likely intensify the regional hydrological cycle over CONUS through the acceleration of the historical trends in cold, warm and wet extremes. Our results show robust changes in the occurrence of severe weather conditions and in the likelihood of ice, freezing rain and snowstorms that may have disruptive impact on large human population across the U.S. More summer like conditions will also drive increase in cooling demands and a net increase in the energy consumption over many regions. We further use an integrated vulnerability index that combines human exposure to different climate extremes (hot, cold, wet and dry) and changes in socioeconomic pathways (due to changes in population and income levels), to reveal that future exposure to potentially damaging climatic conditions will likely increase manifold for population living in major urban centers in California, Texas, Florida, Michigan, Illinois and Northeast. With the current trajectory of emissions, these results warrant that a large human population across the U.S. may feel the impacts of climate change within its lifespan.

  20. Simulating the Evolution of the Human Family: Cooperative Breeding Increases in Harsh Environments

    PubMed Central

    Smaldino, Paul E.; Newson, Lesley; Schank, Jeffrey C.; Richerson, Peter J.

    2013-01-01

    Verbal and mathematical models that consider the costs and benefits of behavioral strategies have been useful in explaining animal behavior and are often used as the basis of evolutionary explanations of human behavior. In most cases, however, these models do not account for the effects that group structure and cultural traditions within a human population have on the costs and benefits of its members' decisions. Nor do they consider the likelihood that cultural as well as genetic traits will be subject to natural selection. In this paper, we present an agent-based model that incorporates some key aspects of human social structure and life history. We investigate the evolution of a population under conditions of different environmental harshness and in which selection can occur at the level of the group as well as the level of the individual. We focus on the evolution of a socially learned characteristic related to individuals' willingness to contribute to raising the offspring of others within their family group. We find that environmental harshness increases the frequency of individuals who make such contributions. However, under the conditions we stipulate, we also find that environmental variability can allow groups to survive with lower frequencies of helpers. The model presented here is inevitably a simplified representation of a human population, but it provides a basis for future modeling work toward evolutionary explanations of human behavior that consider the influence of both genetic and cultural transmission of behavior. PMID:24278318

  1. Simulating the evolution of the human family: cooperative breeding increases in harsh environments.

    PubMed

    Smaldino, Paul E; Newson, Lesley; Schank, Jeffrey C; Richerson, Peter J

    2013-01-01

    Verbal and mathematical models that consider the costs and benefits of behavioral strategies have been useful in explaining animal behavior and are often used as the basis of evolutionary explanations of human behavior. In most cases, however, these models do not account for the effects that group structure and cultural traditions within a human population have on the costs and benefits of its members' decisions. Nor do they consider the likelihood that cultural as well as genetic traits will be subject to natural selection. In this paper, we present an agent-based model that incorporates some key aspects of human social structure and life history. We investigate the evolution of a population under conditions of different environmental harshness and in which selection can occur at the level of the group as well as the level of the individual. We focus on the evolution of a socially learned characteristic related to individuals' willingness to contribute to raising the offspring of others within their family group. We find that environmental harshness increases the frequency of individuals who make such contributions. However, under the conditions we stipulate, we also find that environmental variability can allow groups to survive with lower frequencies of helpers. The model presented here is inevitably a simplified representation of a human population, but it provides a basis for future modeling work toward evolutionary explanations of human behavior that consider the influence of both genetic and cultural transmission of behavior.

  2. Clinical review: Update of avian influenza A infections in humans

    PubMed Central

    Sandrock, Christian; Kelly, Terra

    2007-01-01

    Influenza A viruses have a wide host range for infection, from wild waterfowl to poultry to humans. Recently, the cross-species transmission of avian influenza A, particularly subtype H5N1, has highlighted the importance of the non-human subtypes and their incidence in the human population has increased over the past decade. During cross-species transmission, human disease can range from the asymptomatic to mild conjunctivitis to fulminant pneumonia and death. With these cases, however, the risk for genetic change and development of a novel virus increases, heightening the need for public health and hospital measures. This review discusses the epidemiology, host range, human disease, outcome, treatment, and prevention of cross-transmission of avian influenza A into humans. PMID:17419881

  3. Characterizing the impact of projected changes in climate and ...

    EPA Pesticide Factsheets

    The impact of climate change on human and environmental health is of critical concern. Population exposures to air pollutants both indoors and outdoors are influenced by a wide range of air quality, meteorological, behavioral, and housing-related factors, many of which are also impacted by climate change. An integrated methodology for modeling changes in human exposures to tropospheric ozone (O3) owing to potential future changes in climate and demographics was implemented by linking existing modeling tools for climate, weather, air quality, population distribution, and human exposure. Human exposure results from the Air Pollutants Exposure Model (APEX) for 12 US cities show differences in daily maximum 8-h (DM8H) exposure patterns and levels by sex, age, and city for all scenarios. When climate is held constant and population demographics are varied, minimal difference in O3 exposures is predicted even with the most extreme demographic change scenario. In contrast, when population is held constant, we see evidence of substantial changes in O3 exposure for the most extreme change in climate. Similarly, we see increases in the percentage of the population in each city with at least one O3 exposure exceedance above 60 p.p.b and 70 p.p.b thresholds for future changes in climate. For these climate and population scenarios, the impact of projected changes in climate and air quality on human exposure to O3 are much larger than the impacts of changing demographics.

  4. Hard-to-reach populations of men who have sex with men and sex workers: a systematic review on sampling methods.

    PubMed

    Barros, Ana B; Dias, Sonia F; Martins, Maria Rosario O

    2015-10-30

    In public health, hard-to-reach populations are often recruited by non-probabilistic sampling methods that produce biased results. In order to overcome this, several sampling methods have been improved and developed in the last years. The aim of this systematic review was to identify all current methods used to survey most-at-risk populations of men who have sex with men and sex workers. The review also aimed to assess if there were any relations between the study populations and the sampling methods used to recruit them. Lastly, we wanted to assess if the number of publications originated in middle and low human development (MLHD) countries had been increasing in the last years. A systematic review was conducted using electronic databases and a total of 268 published studies were included in the analysis. In this review, 11 recruitment methods were identified. Semi-probabilistic methods were used most commonly to survey men who have sex with men, and the use of the Internet was the method that gathered more respondents. We found that female sex workers were more frequently recruited through non-probabilistic methods than men who have sex with men (odds = 2.2; p < 0.05; confidence interval (CI) [1.1-4.2]). In the last 6 years, the number of studies based in middle and low human development countries increased more than the number of studies based in very high and high human development countries (odds = 2.5; p < 0.05; CI [1.3-4.9]). This systematic literature review identified 11 methods used to sample men who have sex with men and female sex workers. There is an association between the type of sampling method and the population being studied. The number of studies based in middle and low human development countries has increased in the last 6 years of this study.

  5. Brown bear (Ursus arctos) attacks resulting in human casualties in Scandinavia 1977–2016; management implications and recommendations

    PubMed Central

    Sahlén, Veronica; Arnemo, Jon M.; Sæbø, Solve; Mattsing, Glenn; Kristofferson, Magnus; Brunberg, Sven; Kindberg, Jonas; Swenson, Jon E.

    2018-01-01

    Human persecution and habitat loss have endangered large carnivore populations worldwide, but some are recovering, exacerbating old conflicts. Carnivores can injure and kill people; the most dramatic form of wildlife-human conflict. In Scandinavia, the brown bear (Ursus arctos) population increased from ~500 bears in 1977 to ~3300 in 2008, with an increase in injuries, fatalities, and public fear of bear attacks. We reviewed media coverage and interviewed victims to explore how bear population trends, hunter education, and other factors may have influenced the number of injuries and fatalities in Scandinavia from 1977 to 2016. We found 42 incidents with 42 injuries and 2 fatalities; 42 were adult men, one was an adult woman conducting forestry work, and one was a boy skiing off-piste. Thirty-three adult men were hunting bears, moose, or small game, often with a hunting dog, and 26 had shot at the bear at 8±11 m before injury. Eleven nonhunters were conducting forestry work, inspecting a hunting area, picking berries, tending livestock, hiking, harassing a denned bear, and one person was killed outside his house at night. Eight of the 11 incidents of nonhunters involved female bears with cubs; three of these family groups were in dens and two were on carcasses. The annual number of hunters injured/killed was mostly influenced by the increase in the bear population size. The pattern was similar regarding injuries/fatalities to other outdoor users, but the relation with the bear population size was weaker than for hunters, and the null model was equally supported. Bear physiology at denning may make encounters with bears more risky in the fall, when bears show prehibernation behavior. Awareness and education efforts, especially among hunters, seem important to ensure human safety. Recreationists and forestry workers should avoid dense vegetation or make noise to warn bears of their presence. PMID:29791471

  6. Holocene expansions of Fagus silvatica and Abies alba in Central Europe: where are we after eight decades of debate?

    NASA Astrophysics Data System (ADS)

    Tinner, Willy; Lotter, André F.

    2006-03-01

    During the past eight decades contrasting hypotheses have been put forward to explain the Holocene expansions of Fagus silvatica (beech) and Abies alba (fir) in Central Europe. The hypotheses can be referred to as: (1) climatic change; (2) migrational lag; (3) delay in population increase; (4) human disturbance; and (5) fire disturbance. High-resolution pollen and charcoal records from three sites in lowland Switzerland and southern Germany allow testing the human vs. fire-disturbance hypotheses by means of time-series analysis. Cross-correlations between pairs of pollen as well as between microscopic charcoal and pollen suggest that neither human nor fire disturbance substantially promoted the expansion of Fagus and Abies. We address the remaining hypotheses (climatic change, migrational lag, delay of population increase) by a combined interpretation of our data with independent climatic records and other evidence of past environmental dynamics (e.g. dynamic vegetation modelling) for southern Central Europe. Rapid population expansions in response to cooling and precipitation increase suggest that climatic change was the main forcing factor and that migrational lags were not effective since at least 8200 cal. yr ago. On the basis of this conclusion we propose an explanatory model for the Holocene expansion of Fagus and Abies in Central Europe: Both trees expanded stepwise across the continent during favourable 8200-type events, which were characterized by changes towards wetter and cooler conditions and corresponded to previously recognized Holocene cold phases in Central Europe as well as in the North Atlantic realm. Asynchronous expansions across continental Europe are explained by analogy to today's precipitation gradients resulting from orographic effects. Response lags of Fagus and Abies to climatic change reached a few decades at most, whereas population expansion in response to climatic change lasted for several centuries, probably as a consequence of intrinsic rates of population increase as well as competition with previously established forest communities. This model is in agreement with recent data from northern Central Europe, where large-scale expansion pulses of Fagus coincided with 8200-type events (e.g. 3800-3400 and 2750-2350 cal. BP). In addition to climatic change, human impact influenced the expansions of Fagus in northern Central Europe. We suggest that Abies expansions across Europe after 5000 cal. BP were inhibited by human and/or fire disturbance.

  7. 3-Bromopyruvate inhibits cell proliferation and induces apoptosis in CD133+ population in human glioma.

    PubMed

    Xu, Dong-Qiang; Tan, Xiao-Yu; Zhang, Bao-Wei; Wu, Tao; Liu, Ping; Sun, Shao-Jun; Cao, Yin-Guang

    2016-03-01

    The study was aimed to investigate the role of 3-bromopyruvate in inhibition of CD133+ U87 human glioma cell population growth. The results demonstrated that 3-bromopyruvate inhibited the viability of both CD133+ and parental cells derived from U87 human glioma cell line. However, the 3-bromopyruvate-induced inhibition in viability was more prominent in CD133+ cells at 10 μM concentration after 48 h. Treatment of CD133+ cells with 3-bromopyruvate caused reduction in cell population and cell size, membrane bubbling, and degradation of cell membranes. Hoechst 33258 staining showed condensation of chromatin material and fragmentation of DNA in treated CD133+ cells after 48 h. 3-Bromopyruvate inhibited the migration rate of CD133+ cells significantly compared to the parental cells. Flow cytometry revealed that exposure of CD133+ cells to 3-bromopyruvate increased the cell population in S phase from 24.5 to 37.9 % with increase in time from 12 to 48 h. In addition, 3-bromopyruvate significantly enhanced the expression of Bax and cleaved caspase 3 in CD133+ cells compared to the parental cells. Therefore, 3-bromopyruvate is a potent chemotherapeutic agent for the treatment of glioma by targeting stem cells selectively.

  8. Agricultural greenhouse gas flux determination via remote sensing and modeling

    USDA-ARS?s Scientific Manuscript database

    Serious concerns have been raised about increasing levels of atmospheric greenhouse gases (GHGs) and associated climate change. For every degree in global temperature increase, grain production yields are expected to decrease 10%, while the global human population continues to increase by roughly 8...

  9. Demographic amplification of climate change experienced by the contiguous United States population during the 20(th) century.

    PubMed

    Samson, Jason; Berteaux, Dominique; McGill, Brian J; Humphries, Murray M

    2012-01-01

    Better understanding of the changing relationship between human populations and climate is a global research priority. The 20(th) century in the contiguous United States offers a particularly well-documented example of human demographic expansion during a period of radical socioeconomic and environmental change. One would expect that as human society has been transformed by technology, we would become increasingly decoupled from climate and more dependent on social infrastructure. Here we use spatially-explicit models to evaluate climatic, socio-economic and biophysical correlates of demographic change in the contiguous United States between 1900 and 2000. Climate-correlated variation in population growth has caused the U.S. population to shift its realized climate niche from cool, seasonal climates to warm, aseasonal climates. As a result, the average annual temperature experienced by U.S. citizens between 1920 and 2000 has increased by more than 1.5°C and the temperature seasonality has decreased by 1.1°C during a century when climate change accounted for only a 0.24°C increase in average annual temperature and a 0.15°C decrease in temperature seasonality. Thus, despite advancing technology, climate-correlated demographics continue to be a major feature of contemporary U.S. society. Unfortunately, these demographic patterns are contributing to a substantial warming of the climate niche during a period of rapid environmental warming, making an already bad situation worse.

  10. Demographic Amplification of Climate Change Experienced by the Contiguous United States Population during the 20th Century

    PubMed Central

    Samson, Jason; Berteaux, Dominique; McGill, Brian J.; Humphries, Murray M.

    2012-01-01

    Better understanding of the changing relationship between human populations and climate is a global research priority. The 20th century in the contiguous United States offers a particularly well-documented example of human demographic expansion during a period of radical socioeconomic and environmental change. One would expect that as human society has been transformed by technology, we would become increasingly decoupled from climate and more dependent on social infrastructure. Here we use spatially-explicit models to evaluate climatic, socio-economic and biophysical correlates of demographic change in the contiguous United States between 1900 and 2000. Climate-correlated variation in population growth has caused the U.S. population to shift its realized climate niche from cool, seasonal climates to warm, aseasonal climates. As a result, the average annual temperature experienced by U.S. citizens between 1920 and 2000 has increased by more than 1.5°C and the temperature seasonality has decreased by 1.1°C during a century when climate change accounted for only a 0.24°C increase in average annual temperature and a 0.15°C decrease in temperature seasonality. Thus, despite advancing technology, climate-correlated demographics continue to be a major feature of contemporary U.S. society. Unfortunately, these demographic patterns are contributing to a substantial warming of the climate niche during a period of rapid environmental warming, making an already bad situation worse. PMID:23115624

  11. The Sociocognitive Determinates of HIV/AIDS Prevention Behaviors among Baby Boomers

    ERIC Educational Resources Information Center

    Haynes, Carion R.

    2016-01-01

    Human immunodeficiency virus (HIV) is steadily increasing among the baby boom population. Among this population, there is a gap between knowledge and behavioral choices. HIV risk perception is multifaceted and shaped by different sociodemographic factors. Baby boomers' perception of risk and sociocognitive determinates that impact their decision…

  12. The social and ecological transitions of shrinking cities -- San Juan, Puerto Rico as a case study

    EPA Science Inventory

    Urban populations continue to increase globally and cities have become the dominant human habitat. However, the growth of cities is not universal. One in six cities globally is losing population. Shrinking cities share common attributes such as decreased household income, reduced...

  13. Dietary blueberry improves cognition among older adults in a randomized, double-blind, placebo-controlled trial

    USDA-ARS?s Scientific Manuscript database

    As populations shift to include a larger proportion of older adults, the necessity of research targeting older populations is becoming increasingly apparent. Changes in motor coordination during ‘normal’ aging, in animals and humans, include decrements in balance and locomotion. Parallel to alterati...

  14. Climate change, humans, and the extinction of the woolly mammoth.

    PubMed

    Nogués-Bravo, David; Rodríguez, Jesús; Hortal, Joaquín; Batra, Persaram; Araújo, Miguel B

    2008-04-01

    Woolly mammoths inhabited Eurasia and North America from late Middle Pleistocene (300 ky BP [300,000 years before present]), surviving through different climatic cycles until they vanished in the Holocene (3.6 ky BP). The debate about why the Late Quaternary extinctions occurred has centred upon environmental and human-induced effects, or a combination of both. However, testing these two hypotheses-climatic and anthropogenic-has been hampered by the difficulty of generating quantitative estimates of the relationship between the contraction of the mammoth's geographical range and each of the two hypotheses. We combined climate envelope models and a population model with explicit treatment of woolly mammoth-human interactions to measure the extent to which a combination of climate changes and increased human pressures might have led to the extinction of the species in Eurasia. Climate conditions for woolly mammoths were measured across different time periods: 126 ky BP, 42 ky BP, 30 ky BP, 21 ky BP, and 6 ky BP. We show that suitable climate conditions for the mammoth reduced drastically between the Late Pleistocene and the Holocene, and 90% of its geographical range disappeared between 42 ky BP and 6 ky BP, with the remaining suitable areas in the mid-Holocene being mainly restricted to Arctic Siberia, which is where the latest records of woolly mammoths in continental Asia have been found. Results of the population models also show that the collapse of the climatic niche of the mammoth caused a significant drop in their population size, making woolly mammoths more vulnerable to the increasing hunting pressure from human populations. The coincidence of the disappearance of climatically suitable areas for woolly mammoths and the increase in anthropogenic impacts in the Holocene, the coup de grâce, likely set the place and time for the extinction of the woolly mammoth.

  15. Potential effects of climate change on freshwater ecosystems of the New England/Mid-Atlantic Region

    Treesearch

    Marianne V. Moore; Michael L. Pace; John R. Mather; [and others; [Editor’s note: Patricia A. Flebbe is the SRS co-author for this publication.

    1997-01-01

    Numerous freshwater ecosystems, dense concentrations of humans along the eastern seaboard, extensive forests, and a history of intensive land use distinguish the New England/Mid-Atlantic Region. Human population densities are forecast to increase in portions of the region at the same time that climate is expected to be changing. Consequently, the effects of humans and...

  16. Natural bounds on herbivorous coral reef fishes.

    PubMed

    Heenan, Adel; Hoey, Andrew S; Williams, Gareth J; Williams, Ivor D

    2016-11-30

    Humans are an increasingly dominant driver of Earth's biological communities, but differentiating human impacts from natural drivers of ecosystem state is crucial. Herbivorous fish play a key role in maintaining coral dominance on coral reefs, and are widely affected by human activities, principally fishing. We assess the relative importance of human and biophysical (habitat and oceanographic) drivers on the biomass of five herbivorous functional groups among 33 islands in the central and western Pacific Ocean. Human impacts were clear for some, but not all, herbivore groups. Biomass of browsers, large excavators, and of all herbivores combined declined rapidly with increasing human population density, whereas grazers, scrapers, and detritivores displayed no relationship. Sea-surface temperature had significant but opposing effects on the biomass of detritivores (positive) and browsers (negative). Similarly, the biomass of scrapers, grazers, and detritivores correlated with habitat structural complexity; however, relationships were group specific. Finally, the biomass of browsers and large excavators was related to island geomorphology, both peaking on low-lying islands and atolls. The substantial variability in herbivore populations explained by natural biophysical drivers highlights the need for locally appropriate management targets on coral reefs. © 2016 The Authors.

  17. The World Summit for Social Development.

    PubMed

    1995-01-01

    The three goals of the UN World Summit for Social Development are to attack poverty, build solidarity, and create jobs. Unprecedented population growth has led to recognition of the need for a new, people-centered vision of development to counter the mutually reinforcing threats posed to world stability by poverty, unemployment, and social disintegration. This population growth may result in an inability of humanity to adapt and create unrelenting pressure on the world's natural resources. It has become increasingly recognized that improvements in the status of women will be vital to ensuring the future of humanity. Giving women the ability to decide their family size will eliminate hundreds of thousands of maternal deaths each year and will slow population growth while it increases women's productivity and control over resources. As the industrialized nations engage in unsustainable patterns of production and consumption, the lowest-income countries are caught in a "poverty-population-environment spiral." Although population growth is gradually slowing, the population of the world could double by 2050, with 95% of the growth occurring in developing countries. Concern is also mounting over the increasing urbanization of the world as well as the fact that while the populations of poor countries are becoming larger and younger, the population of industrialized countries are becoming older and smaller. The new vision of sustainable development involves generating economic growth, distributing benefits equitably, and allowing the regeneration of the environment. Without such security, the world can not achieve peace. The symptoms of social discrimination include social exclusion, which affects 90% of the world's population; sex and racial discrimination, which lowers the quality of life and increases life-threatening risks for women, indigenous people, and Blacks; violence and abuse, reflected in fact that the US has the highest incidence of murder in the world, in the 200,000 street children in Brazil, in the 500,000 child prostitutes in Asia, and in violence against women world-wide; crime, which is increasing and is often drug-related; migration, which affects 1/115 people on earth; and conflict, which increasingly occurs within national borders and involves civilian casualties and which leads to military spending of approximately $800 billion a year.

  18. Effect of virgin olive oil and thyme phenolic compounds on blood lipid profile: implications of human gut microbiota.

    PubMed

    Martín-Peláez, Sandra; Mosele, Juana Ines; Pizarro, Neus; Farràs, Marta; de la Torre, Rafael; Subirana, Isaac; Pérez-Cano, Francisco José; Castañer, Olga; Solà, Rosa; Fernandez-Castillejo, Sara; Heredia, Saray; Farré, Magí; Motilva, María José; Fitó, Montserrat

    2017-02-01

    To investigate the effect of virgin olive oil phenolic compounds (PC) alone or in combination with thyme PC on blood lipid profile from hypercholesterolemic humans, and whether the changes generated are related with changes in gut microbiota populations and activities. A randomized, controlled, double-blind, crossover human trial (n = 12) was carried out. Participants ingested 25 mL/day for 3 weeks, preceded by 2-week washout periods, three raw virgin olive oils differing in the concentration and origin of PC: (1) a virgin olive oil (OO) naturally containing 80 mg PC/kg, (VOO), (2) a PC-enriched virgin olive oil containing 500 mg PC/kg, from OO (FVOO), and (3) a PC-enriched virgin olive oil containing a mixture of 500 mg PC/kg from OO and thyme, 1:1 (FVOOT). Blood lipid values and faecal quantitative changes in microbial populations, short chain fatty acids, cholesterol microbial metabolites, bile acids, and phenolic metabolites were analysed. FVOOT decreased seric ox-LDL concentrations compared with pre-FVOOT, and increased numbers of bifidobacteria and the levels of the phenolic metabolite protocatechuic acid compared to VOO (P < 0.05). FVOO did not lead to changes in blood lipid profile nor quantitative changes in the microbial populations analysed, but increased the coprostanone compared to FVOOT (P < 0.05), and the levels of the faecal hydroxytyrosol and dihydroxyphenylacetic acids, compared with pre-intervention values and to VOO, respectively (P < 0.05). The ingestion of a PC-enriched virgin olive oil, containing a mixture of olive oil and thyme PC for 3 weeks, decreases blood ox-LDL in hypercholesterolemic humans. This cardio-protective effect could be mediated by the increases in populations of bifidobacteria together with increases in PC microbial metabolites with antioxidant activities.

  19. Deployment Area Selection and Land Withdrawal/Acquisition. Chapter 4. M-X/MPS (M-X/Multiple Protective Shelter). Volume 1. Environmental Consequences to the Study Regions and Operating Base Vicinities.

    DTIC Science & Technology

    1981-10-02

    to the point of energy imbalance and declining reproductive rates. Increased human population would also increase poaching of pronghorn in areas...reduced. Such effects, however, could be mitigated as discussed below and in ETR-38. Increased human activity, including poaching , harassment, habitat...when intense activity would be widespread in their habitat. Mortality resulting from habitat loss and poaching would decrease herd size during 4-205 4

  20. Gambling on growth.

    PubMed

    Feeney, A

    1990-01-01

    When the assumption is made that economic growth must be increased by 10% to accommodate population increases and to reduce poverty, the question is raised as to whether or not sustainable development is possible. The human population increased 3 times since 1900, and global economic activity has increased 7 times faster than population. Use of fossil fuels has increased by 30 times, and industrial production has increased by 50 times. The by-products of population growth and economic activity are loss of tropical rainforests; species extinction; desertification in Africa, India, and the US; toxic and radioactive pollution; and greenhouse warming and ozone depletion. The atmosphere's stability and human habitation is threatened. Sustainable development, as defined by the World Commission on Environment and Development (WCED) in "Our Common Future," is meeting present needs but not at the expense of future needs. Economic growth must proceed at different rates in different countries to close the gap between the rich and poor. Economic expansion has been criticized by the president of Negative Population Growth and the Environmental Defense Fund's coordinator of reform for the World Bank's environmental policies and Third World countries. US government response during the Reagan administration has been indifference, while support has come from the World Resources Institute, the Worldwatch Institute, the US National Wildlife Federation, and the Population Reference Bureau. Recent support has come from signers of the "G-7 Summit" and from IBM and the Dow Chemical Company. A few shared tenets are 1) that economic development is not sustainable, 2) environmental reforms are necessary to make development sustainable, 3) a trade-off is needed to increase Third World energy use, and 4) population must be stabilized. Many proposals have been offered including reducing population to 2 billion, or 40% of the current level. Reducing poverty globally is an environmentally sound policy. High tariffs and protectionism, debt payments, and International Monetary Fund structural adjustment programs have made the situation worse for the Third World. Many suggestions have been made to correct the poverty imbalance, including no growth or steady state economics.

  1. Human mtDNA hypervariable regions, HVR I and II, hint at deep common maternal founder and subsequent maternal gene flow in Indian population groups.

    PubMed

    Sharma, Swarkar; Saha, Anjana; Rai, Ekta; Bhat, Audesh; Bamezai, Ramesh

    2005-01-01

    We have analysed the hypervariable regions (HVR I and II) of human mitochondrial DNA (mtDNA) in individuals from Uttar Pradesh (UP), Bihar (BI) and Punjab (PUNJ), belonging to the Indo-European linguistic group, and from South India (SI), that have their linguistic roots in Dravidian language. Our analysis revealed the presence of known and novel mutations in both hypervariable regions in the studied population groups. Median joining network analyses based on mtDNA showed extensive overlap in mtDNA lineages despite the extensive cultural and linguistic diversity. MDS plot analysis based on Fst distances suggested increased maternal genetic proximity for the studied population groups compared with other world populations. Mismatch distribution curves, respective neighbour joining trees and other statistical analyses showed that there were significant expansions. The study revealed an ancient common ancestry for the studied population groups, most probably through common founder female lineage(s), and also indicated that human migrations occurred (maybe across and within the Indian subcontinent) even after the initial phase of female migration to India.

  2. Epidemiologic characterization of Colorado backyard bird flocks.

    PubMed

    Smith, Emily I; Reif, John S; Hill, Ashley E; Slota, Katharine E; Miller, Ryan S; Bjork, Kathe E; Pabilonia, Kristy L

    2012-06-01

    Backyard gallinaceous bird flocks may play an important role in the spread of infectious diseases within poultry populations as well as the transmission of zoonotic diseases to humans. An epidemiologic characterization was conducted of Colorado backyard flocks to gather information on general flock characteristics, human movement of birds, human-bird interaction, biosecurity practices, and flock health. Our results suggest that backyard poultry flocks in Colorado are small-sized flocks (68.6% of flocks had < 50 birds); consist primarily of layer chickens (85.49% of flocks), show chickens (32.18% of flocks), and waterfowl (34.07% of flocks); and are primarily owned for food (meat or egg) production for the family (86.44%) or as pet or hobby birds (42.27%). The backyard flock environment may promote bird-to-bird transmission as well as bird-to-human transmission of infectious disease. Birds are primarily housed with free access to the outside (96.85%), and many are moved from the home premises (46.06% within 1 yr). Human contact with backyard flocks is high, biosecurity practices are minimal, and bird health is negatively impacted by increased movement events. Increased knowledge of backyard bird characteristics and associated management practices can provide guidelines for the development of measures to decrease disease transmission between bird populations, decrease disease transmission from birds to humans, and increase the overall health of backyard birds.

  3. Nuclear Genetic Diversity in Human Lice (Pediculus humanus) Reveals Continental Differences and High Inbreeding among Worldwide Populations

    PubMed Central

    Ascunce, Marina S.; Toups, Melissa A.; Kassu, Gebreyes; Fane, Jackie; Scholl, Katlyn; Reed, David L.

    2013-01-01

    Understanding the evolution of parasites is important to both basic and applied evolutionary biology. Knowledge of the genetic structure of parasite populations is critical for our ability to predict how an infection can spread through a host population and for the design of effective control methods. However, very little is known about the genetic structure of most human parasites, including the human louse (Pediculus humanus). This species is composed of two ecotypes: the head louse (Pediculus humanus capitis De Geer), and the clothing (body) louse (Pediculus humanus humanus Linnaeus). Hundreds of millions of head louse infestations affect children every year, and this number is on the rise, in part because of increased resistance to insecticides. Clothing lice affect mostly homeless and refugee-camp populations and although they are less prevalent than head lice, the medical consequences are more severe because they vector deadly bacterial pathogens. In this study we present the first assessment of the genetic structure of human louse populations by analyzing the nuclear genetic variation at 15 newly developed microsatellite loci in 93 human lice from 11 sites in four world regions. Both ecotypes showed heterozygote deficits relative to Hardy–Weinberg equilibrium and high inbreeding values, an expected pattern given their parasitic life history. Bayesian clustering analyses assigned lice to four distinct genetic clusters that were geographically structured. The low levels of gene flow among louse populations suggested that the evolution of insecticide resistance in lice would most likely be affected by local selection pressures, underscoring the importance of tailoring control strategies to population-specific genetic makeup and evolutionary history. Our panel of microsatellite markers provides powerful data to investigate not only ecological and evolutionary processes in lice, but also those in their human hosts because of the long-term coevolutionary association between lice and humans. PMID:23460886

  4. Nuclear genetic diversity in human lice (Pediculus humanus) reveals continental differences and high inbreeding among worldwide populations.

    PubMed

    Ascunce, Marina S; Toups, Melissa A; Kassu, Gebreyes; Fane, Jackie; Scholl, Katlyn; Reed, David L

    2013-01-01

    Understanding the evolution of parasites is important to both basic and applied evolutionary biology. Knowledge of the genetic structure of parasite populations is critical for our ability to predict how an infection can spread through a host population and for the design of effective control methods. However, very little is known about the genetic structure of most human parasites, including the human louse (Pediculus humanus). This species is composed of two ecotypes: the head louse (Pediculus humanus capitis De Geer), and the clothing (body) louse (Pediculus humanus humanus Linnaeus). Hundreds of millions of head louse infestations affect children every year, and this number is on the rise, in part because of increased resistance to insecticides. Clothing lice affect mostly homeless and refugee-camp populations and although they are less prevalent than head lice, the medical consequences are more severe because they vector deadly bacterial pathogens. In this study we present the first assessment of the genetic structure of human louse populations by analyzing the nuclear genetic variation at 15 newly developed microsatellite loci in 93 human lice from 11 sites in four world regions. Both ecotypes showed heterozygote deficits relative to Hardy-Weinberg equilibrium and high inbreeding values, an expected pattern given their parasitic life history. Bayesian clustering analyses assigned lice to four distinct genetic clusters that were geographically structured. The low levels of gene flow among louse populations suggested that the evolution of insecticide resistance in lice would most likely be affected by local selection pressures, underscoring the importance of tailoring control strategies to population-specific genetic makeup and evolutionary history. Our panel of microsatellite markers provides powerful data to investigate not only ecological and evolutionary processes in lice, but also those in their human hosts because of the long-term coevolutionary association between lice and humans.

  5. Seasonal variation in human reproduction: environmental factors.

    PubMed

    Bronson, F H

    1995-06-01

    Almost all human populations exhibit seasonal variation in births, owing mostly to seasonal variation in the frequency of conception. This review focuses on the degree to which environmental factors like nutrition, temperature and photoperiod contribute to these seasonal patterns by acting directly on the reproductive axis. The reproductive strategy of humans is basically that of the apes: Humans have the capacity to reproduce continuously, albeit slowly, unless inhibited by environmental influences. Two, and perhaps three, environmental factors probably act routinely as seasonal inhibitors in some human populations. First, it seems likely that ovulation is regulated seasonally in populations experiencing seasonal variation in food availability. More specifically, it seems likely that inadequate food intake or the increased energy expenditure required to obtain food, or both, can delay menarche, suppress the frequency of ovulation in the nonlactating adult, and prolong lactational amenorrhea in these populations on a seasonal basis. This action is most easily seen in tropical subsistence societies where food availability often varies greatly owing to seasonal variation in rainfall; hence births in these populations often correlate with rainfall. Second, it seems likely that seasonally high temperatures suppress spermatogenesis enough to influence the incidence of fertilization in hotter latitudes, but possibly only in males wearing clothing that diminishes scrotal cooling. Since most of our knowledge about this phenomenon comes from temperate latitudes, the sensitivity of spermatogenesis in both human and nonhuman primates to heat in the tropics needs further study. It is quite possible that high temperatures suppress ovulation and early embryo survival seasonally in some of these same populations. Since we know less than desired about the effect of heat stress on ovulation and early pregnancy in nonhuman mammals, and nothing at all about it in humans or any of the other primates, this is an important area for future research. Third, correlational data suggest that there may be some degree of regulation of reproduction by photoperiod in humans at middle to higher latitudes. Populations at these latitudes often show a peak in presumed conceptions associated with the vernal equinox. On the other hand, evidence gathered by neuroendocrinologists tends to argue against reproductive photoresponsiveness in humans.

  6. A decision framework to enhance sustainable groundwater management

    USDA-ARS?s Scientific Manuscript database

    Groundwater aquifers, which supply water for billions of the world’s inhabitants, are under stress due to increasing human population, water demand for economic development, and environmental constraints. Projected climate change increases uncertainty regarding sustainability of groundwater systems...

  7. Assessing impacts of oil-shale development on the Piceance Basin mule deer herd

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    White, G.C.; Garrott, R.A.

    Development of energy resources on big game ranges generally negatively impacts these important wildlife resources. Although habitat disturbance is generally important, this impact is overshadowed by the negative impacts due to an increasing human population in the area. Increased human activities particularly stress animals during winter periods when inadequate nutrition levels may have already severely impacted the population. Increased road traffic and poaching causes additional deaths, which a decline in survival rates expected, or at least changes in the cause of mortality. This paper describes the experimental design to monitor and mitigate the impact of oil shale development in northwesternmore » Colorado on the Piceance Basin mule deer herd. Biotelemetry techniques are used to measure changes through time in movements, habitat utilization, and survival rates between control and treatment areas. 2 figures.« less

  8. As the raven flies: using genetic data to infer the history of invasive common raven (Corvus corax) populations in the Mojave Desert.

    PubMed

    Fleischer, Robert C; Boarman, William I; Gonzalez, Elena G; Godinez, Alvaro; Omland, Kevin E; Young, Sarah; Helgen, Lauren; Syed, Gracia; McIntosh, Carl E

    2008-01-01

    Common raven (Corvus corax) populations in Mojave Desert regions of southern California and Nevada have increased dramatically over the past five decades. This growth has been attributed to increased human development in the region, as ravens have a commensal relationship with humans and feed extensively at landfills and on road-killed wildlife. Ravens, as a partially subsidized predator, also represent a problem for native desert wildlife, in particular threatened desert tortoises (Gopherus agassizii). However, it is unclear whether the more than 15-fold population increase is due to in situ population growth or to immigration from adjacent regions where ravens have been historically common. Ravens were sampled for genetic analysis at several local sites within five major areas: the West Mojave Desert (California), East Mojave Desert (southern Nevada), southern coastal California, northern coastal California (Bay Area), and northern Nevada (Great Basin). Analyses of mtDNA control region sequences reveal an increased frequency of raven 'Holarctic clade' haplotypes from south to north inland, with 'California clade' haplotypes nearly fixed in the California populations. There was significant structuring among regions for mtDNA, with high F(ST) values among sampling regions, especially between the Nevada and California samples. Analyses of eight microsatellite loci reveal a mostly similar pattern of regional population structure, with considerably smaller, but mostly significant, values. The greater mtDNA divergences may be due to lower female dispersal relative to males, lower N(e), or effects of high mutation rates on maximal values of F(ST). Analyses indicate recent population growth in the West Mojave Desert and a bottleneck in the northern California populations. While we cannot rule out in situ population growth as a factor, patterns of movement inferred from our data suggest that the increase in raven populations in the West Mojave Desert resulted from movements from southern California and the Central Valley. Ravens in the East Mojave Desert are more similar to ones from northern Nevada, indicating movement between those regions. If this interpretation of high gene flow into the Mojave Desert is correct, then efforts to manage raven numbers by local control may not be optimally effective.

  9. The epigenetic lorax: gene–environment interactions in human health

    PubMed Central

    Latham, Keith E; Sapienza, Carmen; Engel, Nora

    2012-01-01

    Over the last decade, we have witnessed an explosion of information on genetic factors underlying common human diseases and disorders. This ‘human genomics’ information revolution has occurred as a backdrop to a rapid increase in the rates of many human disorders and diseases. For example, obesity, Type 2 diabetes, asthma, autism spectrum disorder and attention deficit hyperactivity disorder have increased at rates that cannot be due to changes in the genetic structure of the population, and are difficult to ascribe to changes in diagnostic criteria or ascertainment. A likely cause of the increased incidence of these disorders is increased exposure to environmental factors that modify gene function. Many environmental factors that have epidemiological association with common human disorders are likely to exert their effects through epigenetic alterations. This general mechanism of gene–environment interaction poses special challenges for individuals, educators, scientists and public policy makers in defining, monitoring and mitigating exposures. PMID:22920179

  10. The human footprint in the west: a large-scale analysis of human impacts

    USGS Publications Warehouse

    Leu, Matthias

    2003-01-01

    Background Humans have dramatically altered wildlands in the western United States over the past 100 years by using these lands and the resources they provide. Anthropogenic changes to the landscape, such as urban expansion and development of rural areas, influence the number and kinds of plants and wildlife that remain. In addition, western ecosystems are also affected by roads, powerlines, and other networks and land uses necessary to maintain human populations. The cumulative impacts of human presence and actions on a landscape are called the "human footprint." These impacts may affect plants and wildlife by increasing the number of synanthropic (species that benefit from human activities) bird and mammal predators and facilitating their movements through the landscape or by creating unsuitable habitats. These actions can impact plants and wildlife to such an extent that the persistence of populations or entire species is questionable. For example, greater sage-grouse (Centrocercus urophasianus) once were widespread throughout the Great Basin, but now are a focus of conservation concern because populations have declined for the past three decades across most of their range. At the USGS Forest and Rangeland Ecosystem Science Center, we are developing spatial models to better understand potential influences of the human footprint on shrubland ecosystems and associated wildlife in the western United States.

  11. Human Prostate Side Population Cells Demonstrate Stem Cell Properties in Recombination with Urogenital Sinus Mesenchyme

    PubMed Central

    Foster, Barbara A.; Gangavarapu, Kalyan J.; Mathew, Grinu; Azabdaftari, Gissou; Morrison, Carl D.; Miller, Austin; Huss, Wendy J.

    2013-01-01

    Stem cell enrichment provides a tool to examine prostate stem cells obtained from benign and malignant tissue. Functional assays can enrich stem cells based on common stem cell phenotypes, such as high ATP binding cassette (ABC) transporter mediated efflux of Hoechst substrates (side population assay). This functional assay is based upon mechanisms that protect cells from environmental insult thus contributing to the survival and protection of the stem cell population. We have isolated and analyzed cells digested from twelve clinical prostate specimens based on the side population assay. Prostate stem cell properties of the isolated cells were tested by serial recombination with rat urogenital mesenchyme. Recombinants with side population cells demonstrate an increase in the frequency of human ductal growth and the number of glands per recombinant when compared to recombinants with non-side population cells. Isolated cells were capable of prostatic growth for up to three generations in the recombination assay with as little as 125 sorted prostate cells. The ability to reproducibly use cells isolated by fluorescence activated cell sorting from human prostate tissue is an essential step to a better understanding of human prostate stem cell biology. ABC transporter G2 (ABCG2) was expressed in recombinants from side population cells indicating the side population cells have self-renewal properties. Epithelial cell differentiation of recombinants was determined by immunohistochemical analysis for expression of the basal, luminal, and neuroendocrine markers, p63, androgen receptor, prostate specific antigen, and chromogranin A, respectively. Thus, the ABCG2 expressing side population demonstrates multipotency and self-renewal properties indicating stem cells are within this population. PMID:23383057

  12. Hierarchical Genetic Analysis of German Cockroach (Blattella germanica) Populations from within Buildings to across Continents

    PubMed Central

    Vargo, Edward L.; Crissman, Jonathan R.; Booth, Warren; Santangelo, Richard G.; Mukha, Dmitry V.; Schal, Coby

    2014-01-01

    Understanding the population structure of species that disperse primarily by human transport is essential to predicting and controlling human-mediated spread of invasive species. The German cockroach (Blattella germanica) is a widespread urban invader that can actively disperse within buildings but is spread solely by human-mediated dispersal over longer distances; however, its population structure is poorly understood. Using microsatellite markers we investigated population structure at several spatial scales, from populations within single apartment buildings to populations from several cities across the U.S. and Eurasia. Both traditional measures of genetic differentiation and Bayesian clustering methods revealed increasing levels of genetic differentiation at greater geographic scales. Our results are consistent with active dispersal of cockroaches largely limited to movement within a building. Their low levels of genetic differentiation, yet limited active spread between buildings, suggests a greater likelihood of human-mediated dispersal at more local scales (within a city) than at larger spatial scales (within and between continents). About half the populations from across the U.S. clustered together with other U.S. populations, and isolation by distance was evident across the U.S. Levels of genetic differentiation among Eurasian cities were greater than those in the U.S. and greater than those between the U.S. and Eurasia, but no clear pattern of structure at the continent level was detected. MtDNA sequence variation was low and failed to reveal any geographical structure. The weak genetic structure detected here is likely due to a combination of historical admixture among populations and periodic population bottlenecks and founder events, but more extensive studies are needed to determine whether signatures of global movement may be present in this species. PMID:25020136

  13. Estimating large carnivore populations at global scale based on spatial predictions of density and distribution – Application to the jaguar (Panthera onca)

    PubMed Central

    Robinson, Hugh S.; Abarca, Maria; Zeller, Katherine A.; Velasquez, Grisel; Paemelaere, Evi A. D.; Goldberg, Joshua F.; Payan, Esteban; Hoogesteijn, Rafael; Boede, Ernesto O.; Schmidt, Krzysztof; Lampo, Margarita; Viloria, Ángel L.; Carreño, Rafael; Robinson, Nathaniel; Lukacs, Paul M.; Nowak, J. Joshua; Salom-Pérez, Roberto; Castañeda, Franklin; Boron, Valeria; Quigley, Howard

    2018-01-01

    Broad scale population estimates of declining species are desired for conservation efforts. However, for many secretive species including large carnivores, such estimates are often difficult. Based on published density estimates obtained through camera trapping, presence/absence data, and globally available predictive variables derived from satellite imagery, we modelled density and occurrence of a large carnivore, the jaguar, across the species’ entire range. We then combined these models in a hierarchical framework to estimate the total population. Our models indicate that potential jaguar density is best predicted by measures of primary productivity, with the highest densities in the most productive tropical habitats and a clear declining gradient with distance from the equator. Jaguar distribution, in contrast, is determined by the combined effects of human impacts and environmental factors: probability of jaguar occurrence increased with forest cover, mean temperature, and annual precipitation and declined with increases in human foot print index and human density. Probability of occurrence was also significantly higher for protected areas than outside of them. We estimated the world’s jaguar population at 173,000 (95% CI: 138,000–208,000) individuals, mostly concentrated in the Amazon Basin; elsewhere, populations tend to be small and fragmented. The high number of jaguars results from the large total area still occupied (almost 9 million km2) and low human densities (< 1 person/km2) coinciding with high primary productivity in the core area of jaguar range. Our results show the importance of protected areas for jaguar persistence. We conclude that combining modelling of density and distribution can reveal ecological patterns and processes at global scales, can provide robust estimates for use in species assessments, and can guide broad-scale conservation actions. PMID:29579129

  14. NET ANTHROPOGENIC PHOSPHORUS INPUTS; SPATIAL AND TEMPORAL VARIABILITY IN THE CHESAPEAKE BAY REGION

    EPA Science Inventory

    Coastal watershed eutrophication has increasingly become a regional and global issue as larger proportions of the earth’s human population settle in coastal areas. Human activities on the land have severely impacted the water resources of the Chesapeake Bay, one of the world’s l...

  15. Dog ownership and all-cause mortality in a population cohort in Norway: The HUNT study

    PubMed Central

    Krokstad, Steinar; Stamatakis, Emmanuel; Bauman, Adrian

    2017-01-01

    Objective There has been increased interest in human-animal interactions and their possible effects on human health. Some of this research has focused on human physical activity levels, mediated through increased dog walking. Much of the reported research has been cross sectional, and very few epidemiological studies have examined the association between dog ownership and mortality in populations. Methods We used data from the Norwegian county population-based Nord-Trøndelag HUNT Study (HUNT2, 1995–1997). Cox proportional hazards models were fitted to analyse the relationship between dog ownership and all-cause mortality. The median follow-up time was 18.5 years and the maximum follow-up time was 19.7 years. Results In this population, dog owners were no more physically active than non-dog owners, both groups reporting a total of just over 3 hours/week of light and vigorous activity. Dog owners (n = 25,031, with 1,587 deaths during follow-up; 504,017 person-years of time at risk) had virtually the same hazard of dying as non-dog owners (Hazard ratio 1.00, 95% CI 0.91–1.09). Conclusions We found no evidence for an association between the presence of a dog in the household and all-cause mortality or physical activity levels in this Norwegian population. Further epidemiological research is needed to clarify this relationship, as methodological limitations and an active Norwegian population sample means that generalizable evidence is not yet clear on dog ownership and mortality. PMID:28662069

  16. Human impact on wildfires varies between regions and with vegetation productivity

    NASA Astrophysics Data System (ADS)

    Lasslop, Gitta; Kloster, Silvia

    2017-11-01

    We assess the influence of humans on burned area simulated with a dynamic global vegetation model. The human impact in the model is based on population density and cropland fraction, which were identified as important drivers of burned area in analyses of global datasets, and are commonly used in global models. After an evaluation of the sensitivity to these two variables we extend the model by including an additional effect of the cropland fraction on the fire duration. The general pattern of human influence is similar in both model versions: the strongest human impact is found in regions with intermediate productivity, where fire occurrence is not limited by fuel load or climatic conditions. Human effects in the model increases burned area in the tropics, while in temperate regions burned area is reduced. While the population density is similar on average for the tropical and temperate regions, the cropland fraction is higher in temperate regions, and leads to a strong suppression of fire. The model shows a low human impact in the boreal region, where both population density and cropland fraction is very low and the climatic conditions, as well as the vegetation productivity limit fire. Previous studies attributed a decrease in fire activity found in global charcoal datasets to human activity. This is confirmed by our simulations, which only show a decrease in burned area when the human influence on fire is accounted for, and not with only natural effects on fires. We assess how the vegetation-fire feedback influences the results, by comparing simulations with dynamic vegetation biogeography to simulations with prescribed vegetation. The vegetation-fire feedback increases the human impact on burned area by 10% for present day conditions. These results emphasize that projections of burned area need to account for the interactions between fire, climate, vegetation and humans.

  17. Network Models: An Underutilized Tool in Wildlife Epidemiology?

    PubMed Central

    Craft, Meggan E.; Caillaud, Damien

    2011-01-01

    Although the approach of contact network epidemiology has been increasing in popularity for studying transmission of infectious diseases in human populations, it has generally been an underutilized approach for investigating disease outbreaks in wildlife populations. In this paper we explore the differences between the type of data that can be collected on human and wildlife populations, provide an update on recent advances that have been made in wildlife epidemiology by using a network approach, and discuss why networks might have been underutilized and why networks could and should be used more in the future. We conclude with ideas for future directions and a call for field biologists and network modelers to engage in more cross-disciplinary collaboration. PMID:21527981

  18. Response of human populations to large-scale emergencies

    NASA Astrophysics Data System (ADS)

    Bagrow, James; Wang, Dashun; Barabási, Albert-László

    2010-03-01

    Until recently, little quantitative data regarding collective human behavior during dangerous events such as bombings and riots have been available, despite its importance for emergency management, safety and urban planning. Understanding how populations react to danger is critical for prediction, detection and intervention strategies. Using a large telecommunications dataset, we study for the first time the spatiotemporal, social and demographic response properties of people during several disasters, including a bombing, a city-wide power outage, and an earthquake. Call activity rapidly increases after an event and we find that, when faced with a truly life-threatening emergency, information rapidly propagates through a population's social network. Other events, such as sports games, do not exhibit this propagation.

  19. Population growth as a driver of initial domestication in Eastern North America

    PubMed Central

    Codding, Brian F.

    2016-01-01

    The transition to agriculture is one of the most significant events in human prehistory; yet, explaining why people initially domesticated plants and animals remains a contentious research problem in archaeology. Two competing hypotheses dominate current debates. The first draws on niche construction theory to emphasize how intentional management of wild resources should lead to domestication regardless of Malthusian population–resource imbalances. The second relies on models from behavioural ecology (BE) to highlight how individuals should only exert selective pressure on wild resources during times of population–resource imbalance. We examine these hypotheses to explain the domestication event which occurred in Eastern North America approximately 5000 years ago. Using radiocarbon date density and site counts as proxies for human population, we find that populations increased significantly in the 1000 years prior to initial domestication. We therefore suggest that high populations prior to 5000 cal BP may have experienced competition for and possibly overexploitation of resources, altering the selective pressures on wild plants thereby producing domesticates. These findings support the BE hypothesis of domestication occurring in the context of population–resource imbalances. Such deficits, driven either by increased populations or decreased resource abundance, are predicted to characterize domestication events elsewhere. PMID:27853610

  20. Harvesting strategies for increasing the availability and quality of hardwood fiber

    Treesearch

    Chris B. LeDoux

    1999-01-01

    Worldwide demand for wood and wood products will continue to increase as global human population increases. These increasing demands for wood will continue to provide economic incentives for non-industrial private forest-land (NIPF) owners to increase the availability and quality of wood fiber harvested from their lands. The challenge is to encourage and facilitate...

  1. Growing pains: How risk perception and risk communication research can help to manage the challenges of global population growth.

    PubMed

    Dawson, Ian G J; Johnson, Johnnie E V

    2014-08-01

    In 2011, the global human population reached 7 billion and medium variant projections indicate that it will exceed 9 billion before 2045. Theoretical and empirical perspectives suggest that this growth could lead to an increase in the likelihood of adverse events (e.g., food shortages, climate change, etc.) and/or the severity of adverse events (e.g., famines, natural disasters, etc.). Several scholars have posited that the size to which the global population grows and the extent to which this growth increases the likelihood of adverse outcomes will largely be shaped by individuals' decisions (in households, organizations, governments, etc.). In light of the strong relationship between perceived risk and decision behaviors, it is surprising that there remains a dearth of empirical research that specifically examines the perceived risks of population growth and how these perceptions might influence related decisions. In an attempt to motivate this important strand of research, this article examines the major risks that may be exacerbated by global population growth and draws upon empirical work concerning the perception and communication of risk to identify potential directions for future research. The article also considers how individuals might perceive both the risks and benefits of population growth and be helped to better understand and address the related issues. The answers to these questions could help humanity better manage the emerging consequences of its continuing success in increasing infant survival and adult longevity. © 2014 Society for Risk Analysis.

  2. Population policies, programmes and the environment

    PubMed Central

    Speidel, J. Joseph; Weiss, Deborah C.; Ethelston, Sally A.; Gilbert, Sarah M.

    2009-01-01

    Human consumption is depleting the Earth's natural resources and impairing the capacity of life-supporting ecosystems. Humans have changed ecosystems more rapidly and extensively over the past 50 years than during any other period, primarily to meet increasing demands for food, fresh water, timber, fibre and fuel. Such consumption, together with world population increasing from 2.6 billion in 1950 to 6.8 billion in 2009, are major contributors to environmental damage. Strengthening family-planning services is crucial to slowing population growth, now 78 million annually, and limiting population size to 9.2 billion by 2050. Otherwise, birth rates could remain unchanged, and world population would grow to 11 billion. Of particular concern are the 80 million annual pregnancies (38% of all pregnancies) that are unintended. More than 200 million women in developing countries prefer to delay their pregnancy, or stop bearing children altogether, but rely on traditional, less-effective methods of contraception or use no method because they lack access or face other barriers to using contraception. Family-planning programmes have a successful track record of reducing unintended pregnancies, thereby slowing population growth. An estimated $15 billion per year is needed for family-planning programmes in developing countries and donors should provide at least $5 billion of the total, however, current donor assistance is less than a quarter of this funding target. PMID:19770155

  3. Weedy (red) rice: An emerging constraint to global rice production

    USDA-ARS?s Scientific Manuscript database

    Ongoing increases in the human population necessitate that rice will continue to be an essential aspect of food security for the 21st century. While production must increase in the coming decades to meet demand, such increases will be accompanied by diminished natural resources and rising productio...

  4. Trends and drivers of marine debris on the Atlantic coast of the United States 1997-2007

    USGS Publications Warehouse

    Ribic, C.A.; Sheavly, S.B.; Rugg, D.J.; Erdmann, Eric S.

    2010-01-01

    For the first time, we documented regional differences in amounts and long-term trends of marine debris along the US Atlantic coast. The Southeast Atlantic had low land-based and general-source debris loads as well as no increases despite a 19% increase in coastal population. The Northeast (8% population increase) also had low land-based and general-source debris loads and no increases. The Mid-Atlantic (10% population increase) fared the worst, with heavy land-based and general-source debris loads that increased over time. Ocean-based debris did not change in the Northeast where the fishery is relatively stable; it declined over the Mid-Atlantic and Southeast and was correlated with declining regional fisheries. Drivers, including human population, land use status, fishing activity, and oceanic current systems, had complex relationships with debris loads at local and regional scales. Management challenges remain undeniably large but solid information from long-term programs is one key to addressing this pressing pollution issue. ?? 2010.

  5. Trends and drivers of marine debris on the Atlantic coast of the United States 1997-2007.

    PubMed

    Ribic, Christine A; Sheavly, Seba B; Rugg, David J; Erdmann, Eric S

    2010-08-01

    For the first time, we documented regional differences in amounts and long-term trends of marine debris along the US Atlantic coast. The Southeast Atlantic had low land-based and general-source debris loads as well as no increases despite a 19% increase in coastal population. The Northeast (8% population increase) also had low land-based and general-source debris loads and no increases. The Mid-Atlantic (10% population increase) fared the worst, with heavy land-based and general-source debris loads that increased over time. Ocean-based debris did not change in the Northeast where the fishery is relatively stable; it declined over the Mid-Atlantic and Southeast and was correlated with declining regional fisheries. Drivers, including human population, land use status, fishing activity, and oceanic current systems, had complex relationships with debris loads at local and regional scales. Management challenges remain undeniably large but solid information from long-term programs is one key to addressing this pressing pollution issue. Published by Elsevier Ltd.

  6. Patterns of Snow Leopard Site Use in an Increasingly Human-Dominated Landscape

    PubMed Central

    2016-01-01

    Human population growth and concomitant increases in demand for natural resources pose threats to many wildlife populations. The landscapes used by the endangered snow leopard (Panthera uncia) and their prey is increasingly subject to major changes in land use. We aimed to assess the influence of 1) key human activities, as indicated by the presence of mining and livestock herding, and 2) the presence of a key prey species, the blue sheep (Pseudois nayaur), on probability of snow leopard site use across the landscape. In Gansu Province, China, we conducted sign surveys in 49 grid cells, each of 16 km2 in size, within a larger area of 3392 km2. We analysed the data using likelihood-based habitat occupancy models that explicitly account for imperfect detection and spatial auto-correlation between survey transect segments. The model-averaged estimate of snow leopard occupancy was high [0.75 (SE 0.10)], but only marginally higher than the naïve estimate (0.67). Snow leopard segment-level probability of detection, given occupancy on a 500 m spatial replicate, was also high [0.68 (SE 0.08)]. Prey presence was the main determinant of snow leopard site use, while human disturbances, in the form of mining and herding, had low predictive power. These findings suggest that snow leopards continue to use areas very close to such disturbances, as long as there is sufficient prey. Improved knowledge about the effect of human activity on large carnivores, which require large areas and intact prey populations, is urgently needed for conservation planning at the local and global levels. We highlight a number of methodological considerations that should guide the design of such research. PMID:27171203

  7. Patterns of Snow Leopard Site Use in an Increasingly Human-Dominated Landscape.

    PubMed

    Alexander, Justine Shanti; Gopalaswamy, Arjun M; Shi, Kun; Hughes, Joelene; Riordan, Philip

    2016-01-01

    Human population growth and concomitant increases in demand for natural resources pose threats to many wildlife populations. The landscapes used by the endangered snow leopard (Panthera uncia) and their prey is increasingly subject to major changes in land use. We aimed to assess the influence of 1) key human activities, as indicated by the presence of mining and livestock herding, and 2) the presence of a key prey species, the blue sheep (Pseudois nayaur), on probability of snow leopard site use across the landscape. In Gansu Province, China, we conducted sign surveys in 49 grid cells, each of 16 km2 in size, within a larger area of 3392 km2. We analysed the data using likelihood-based habitat occupancy models that explicitly account for imperfect detection and spatial auto-correlation between survey transect segments. The model-averaged estimate of snow leopard occupancy was high [0.75 (SE 0.10)], but only marginally higher than the naïve estimate (0.67). Snow leopard segment-level probability of detection, given occupancy on a 500 m spatial replicate, was also high [0.68 (SE 0.08)]. Prey presence was the main determinant of snow leopard site use, while human disturbances, in the form of mining and herding, had low predictive power. These findings suggest that snow leopards continue to use areas very close to such disturbances, as long as there is sufficient prey. Improved knowledge about the effect of human activity on large carnivores, which require large areas and intact prey populations, is urgently needed for conservation planning at the local and global levels. We highlight a number of methodological considerations that should guide the design of such research.

  8. Fishing degrades size structure of coral reef fish communities.

    PubMed

    Robinson, James P W; Williams, Ivor D; Edwards, Andrew M; McPherson, Jana; Yeager, Lauren; Vigliola, Laurent; Brainard, Russell E; Baum, Julia K

    2017-03-01

    Fishing pressure on coral reef ecosystems has been frequently linked to reductions of large fishes and reef fish biomass. Associated impacts on overall community structure are, however, less clear. In size-structured aquatic ecosystems, fishing impacts are commonly quantified using size spectra, which describe the distribution of individual body sizes within a community. We examined the size spectra and biomass of coral reef fish communities at 38 US-affiliated Pacific islands that ranged in human presence from near pristine to human population centers. Size spectra 'steepened' steadily with increasing human population and proximity to market due to a reduction in the relative biomass of large fishes and an increase in the dominance of small fishes. Reef fish biomass was substantially lower on inhabited islands than uninhabited ones, even at inhabited islands with the lowest levels of human presence. We found that on populated islands size spectra exponents decreased (analogous to size spectra steepening) linearly with declining biomass, whereas on uninhabited islands there was no relationship. Size spectra were steeper in regions of low sea surface temperature but were insensitive to variation in other environmental and geomorphic covariates. In contrast, reef fish biomass was highly sensitive to oceanographic conditions, being influenced by both oceanic productivity and sea surface temperature. Our results suggest that community size structure may be a more robust indicator than fish biomass to increasing human presence and that size spectra are reliable indicators of exploitation impacts across regions of different fish community compositions, environmental drivers, and fisheries types. Size-based approaches that link directly to functional properties of fish communities, and are relatively insensitive to abiotic variation across biogeographic regions, offer great potential for developing our understanding of fishing impacts in coral reef ecosystems. © 2016 John Wiley & Sons Ltd.

  9. Plague Circulation and Population Genetics of the Reservoir Rattus rattus: The Influence of Topographic Relief on the Distribution of the Disease within the Madagascan Focus

    PubMed Central

    Brouat, Carine; Rahelinirina, Soanandrasana; Loiseau, Anne; Rahalison, Lila; Rajerison, Minoariso; Laffly, Dominique; Handschumacher, Pascal; Duplantier, Jean-Marc

    2013-01-01

    Background Landscape may affect the distribution of infectious diseases by influencing the population density and dispersal of hosts and vectors. Plague (Yersinia pestis infection) is a highly virulent, re-emerging disease, the ecology of which has been scarcely studied in Africa. Human seroprevalence data for the major plague focus of Madagascar suggest that plague spreads heterogeneously across the landscape as a function of the relief. Plague is primarily a disease of rodents. We therefore investigated the relationship between disease distribution and the population genetic structure of the black rat, Rattus rattus, the main reservoir of plague in Madagascar. Methodology/Principal Findings We conducted a comparative study of plague seroprevalence and genetic structure (15 microsatellite markers) in rat populations from four geographic areas differing in topology, each covering about 150–200 km2 within the Madagascan plague focus. The seroprevalence levels in the rat populations mimicked those previously reported for humans. As expected, rat populations clearly displayed a more marked genetic structure with increasing relief. However, the relationship between seroprevalence data and genetic structure differs between areas, suggesting that plague distribution is not related everywhere to the effective dispersal of rats. Conclusions/Significance Genetic diversity estimates suggested that plague epizootics had only a weak impact on rat population sizes. In the highlands of Madagascar, plague dissemination cannot be accounted for solely by the effective dispersal of the reservoir. Human social activities may also be involved in spreading the disease in rat and human populations. PMID:23755317

  10. The need for agriculture phenotyping: "moving from genotype to phenotype".

    PubMed

    Boggess, Mark V; Lippolis, John D; Hurkman, William J; Fagerquist, Clifton K; Briggs, Steve P; Gomes, Aldrin V; Righetti, Pier Giorgio; Bala, Kumar

    2013-11-20

    Increase in the world population has called for the increased demand for agricultural productivity. Traditional methods to augment crop and animal production are facing exacerbating pressures in keeping up with population growth. This challenge has in turn led to the transformational change in the use of biotechnology tools to meet increased productivity for both plant and animal systems. Although many challenges exist, the use of proteomic techniques to understand agricultural problems is steadily increasing. This review discusses the impact of genomics, proteomics, metabolomics and phenotypes on plant, animal and bacterial systems to achieve global food security and safety and we highlight examples of intra and extra mural research work that is currently being done to increase agricultural productivity. This review focuses on the global demand for increased agricultural productivity arising from population growth and how we can address this challenge using biotechnology. With a population well above seven billion humans, in a very unbalanced nutritional state (20% overweight, 20% risking starvation) drastic measures have to be taken at the political, infrastructure and scientific levels. While we cannot influence politics, it is our duty as scientists to see what can be done to feed humanity. Hence we highlight the transformational change in the use of biotechnology tools over traditional methods to increase agricultural productivity (plant and animal). Specifically, this review deals at length on how a three-pronged attack, namely combined genomics, proteomics and metabolomics, can help to ensure global food security and safety. This article is part of a Special Issue entitled: Translational Plant Proteomics. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Discontinuity of Human Presence at Atapuerca during the Early Middle Pleistocene: A Matter of Ecological Competition?

    PubMed Central

    Rodríguez-Gómez, Guillermo; Mateos, Ana; Martín-González, Jesús Angel; Blasco, Ruth; Rosell, Jordi; Rodríguez, Jesús

    2014-01-01

    Increasing evidence suggests that the European human settlement is older than 1.2 Ma. However, there is a fierce debate about the continuity or discontinuity of the early human settlement of Europe. In particular, evidence of human presence in the interval 0.7−0.5 Ma is scarce in comparison with evidence for the previous and later periods. Here, we present a case study in which the environmental conditions at Sierra de Atapuerca in the early Middle Pleistocene, a period without evidence of human presence, are compared with the conditions in the previous period, for which a relatively intense human occupation is documented. With this objective in mind, the available resources for a human population and the intensity of competition between secondary consumers during the two periods are compared using a mathematical model. The Gran Dolina site TD8 level, dated to 0.7−0.6 Ma, is taken as representative of the period during which Atapuerca was apparently not occupied by humans. Conditions at TD8 are compared with those of the previous period, represented by the TD6-2 level, which has yielded abundant evidence of intense human occupation. The results show that survival opportunities for a hypothetical human population were lower at TD8 than they were at TD6-2. Increased resource competition between secondary consumers arises as a possible explanation for the absence of human occupation at Atapuerca in the early Middle Pleistocene. PMID:25054305

  12. Discontinuity of human presence at Atapuerca during the early Middle Pleistocene: a matter of ecological competition?

    PubMed

    Rodríguez-Gómez, Guillermo; Mateos, Ana; Martín-González, Jesús Angel; Blasco, Ruth; Rosell, Jordi; Rodríguez, Jesús

    2014-01-01

    Increasing evidence suggests that the European human settlement is older than 1.2 Ma. However, there is a fierce debate about the continuity or discontinuity of the early human settlement of Europe. In particular, evidence of human presence in the interval 0.7-0.5 Ma is scarce in comparison with evidence for the previous and later periods. Here, we present a case study in which the environmental conditions at Sierra de Atapuerca in the early Middle Pleistocene, a period without evidence of human presence, are compared with the conditions in the previous period, for which a relatively intense human occupation is documented. With this objective in mind, the available resources for a human population and the intensity of competition between secondary consumers during the two periods are compared using a mathematical model. The Gran Dolina site TD8 level, dated to 0.7-0.6 Ma, is taken as representative of the period during which Atapuerca was apparently not occupied by humans. Conditions at TD8 are compared with those of the previous period, represented by the TD6-2 level, which has yielded abundant evidence of intense human occupation. The results show that survival opportunities for a hypothetical human population were lower at TD8 than they were at TD6-2. Increased resource competition between secondary consumers arises as a possible explanation for the absence of human occupation at Atapuerca in the early Middle Pleistocene.

  13. Open Access Resources for Genome Wide Association Studies (GWAS) in rice (Oryza sativa) illustrate the power of population-specific mapping

    USDA-ARS?s Scientific Manuscript database

    Increasing food production is essential to meet the demands of a growing human population, with its rising income levels and nutritional expectations. New sources of genetic variation are key to enhancing the productivity, sustainability and resilience of crop varieties and agricultural systems that...

  14. Integrated crop pollination: Combining strategies to ensure stable and sustainable yields of pollination-dependent crops

    USDA-ARS?s Scientific Manuscript database

    Meeting the nutritional needs of our growing human population will be increasingly dependent on bees and other pollinators that provide the essential delivery of pollen to crop flowers during bloom. Honey bees have experienced population declines in some regions, and similar changes are evident for ...

  15. Management implications of cowbird parasitism on neotropical migrant songbirds

    Treesearch

    Scott K. Robinson; Joseph A. Grzybowski; Stephen I. Rothstein; Margaret C. Brittingham; Lisa J. Petit; Frank R. Thompson

    1993-01-01

    Populations of brood parasitic Brown-headed Cowbirds (Molofhrus afer) have increased to the point where they pose a potential threat to populations of many neotropical migrant songbirds. Because cowbirds mostly feed in short grass (e.g., pastures and lawns) or on bare ground (e.g., row crops), they benefit directly from human activities. Cowbirds...

  16. S-phenylmercapturic acid (S-PMA) levels in urine as an indicator of exposure to benzene in the Kinshasa population.

    PubMed

    Tuakuila, J

    2013-07-01

    Data on human exposure to chemicals in Africa are scarce. A biomonitoring study was conducted in a representative sample of the population in Kinshasa (Democratic Republic of Congo) to document exposure to benzene. S-phenylmercapturic acid (S-PMA) was measured by LC-MS/MS in spot urine samples from 220 individuals (50.5% women), aged 6-70 years living in the urban area and from 50 additional subjects from the sub-rural area of Kinshasa. Data were compiled as arithmetic means, geometric means, percentile 95th and range expressed in μg/L. Overall, living in urban Kinshasa was associated with increased levels of S-PMA in urine as compared to a population living in the sub-rural area. Increased levels were also found by comparison with some date from literature. This study reveals the high benzene exposure of the Kinshasa population requiring the determination of benzene concentrations in ambient air of Kinshasa and limit values for the protection of human health. Copyright © 2013 Elsevier GmbH. All rights reserved.

  17. Large-scale absence of sharks on reefs in the greater-Caribbean: a footprint of human pressures.

    PubMed

    Ward-Paige, Christine A; Mora, Camilo; Lotze, Heike K; Pattengill-Semmens, Christy; McClenachan, Loren; Arias-Castro, Ery; Myers, Ransom A

    2010-08-05

    In recent decades, large pelagic and coastal shark populations have declined dramatically with increased fishing; however, the status of sharks in other systems such as coral reefs remains largely unassessed despite a long history of exploitation. Here we explore the contemporary distribution and sighting frequency of sharks on reefs in the greater-Caribbean and assess the possible role of human pressures on observed patterns. We analyzed 76,340 underwater surveys carried out by trained volunteer divers between 1993 and 2008. Surveys were grouped within one km2 cells, which allowed us to determine the contemporary geographical distribution and sighting frequency of sharks. Sighting frequency was calculated as the ratio of surveys with sharks to the total number of surveys in each cell. We compared sighting frequency to the number of people in the cell vicinity and used population viability analyses to assess the effects of exploitation on population trends. Sharks, with the exception of nurse sharks occurred mainly in areas with very low human population or strong fishing regulations and marine conservation. Population viability analysis suggests that exploitation alone could explain the large-scale absence; however, this pattern is likely to be exacerbated by additional anthropogenic stressors, such as pollution and habitat degradation, that also correlate with human population. Human pressures in coastal zones have lead to the broad-scale absence of sharks on reefs in the greater-Caribbean. Preventing further loss of sharks requires urgent management measures to curb fishing mortality and to mitigate other anthropogenic stressors to protect sites where sharks still exist. The fact that sharks still occur in some densely populated areas where strong fishing regulations are in place indicates the possibility of success and encourages the implementation of conservation measures.

  18. Generation of Human Induced Pluripotent Stem Cells Using RNA-Based Sendai Virus System and Pluripotency Validation of the Resulting Cell Population.

    PubMed

    Chichagova, Valeria; Sanchez-Vera, Irene; Armstrong, Lyle; Steel, David; Lako, Majlinda

    2016-01-01

    Human induced pluripotent stem cells (hiPSCs) provide a platform for studying human disease in vitro, increase our understanding of human embryonic development, and provide clinically relevant cell types for transplantation, drug testing, and toxicology studies. Since their discovery, numerous advances have been made in order to eliminate issues such as vector integration into the host genome, low reprogramming efficiency, incomplete reprogramming and acquisition of genomic instabilities. One of the ways to achieve integration-free reprogramming is by using RNA-based Sendai virus. Here we describe a method to generate hiPSCs with Sendai virus in both feeder-free and feeder-dependent culture systems. Additionally, we illustrate methods by which to validate pluripotency of the resulting stem cell population.

  19. Population structure of the Chagas disease vector, Triatoma infestans, at the urban-rural interface

    PubMed Central

    Foley, Erica A.; Khatchikian, Camilo E.; Hwang, Josephine; Ancca-Juárez, Jenny; Borrini-Mayori, Katty; Quıspe-Machaca, Victor R.; Levy, Michael Z.; Brisson, Dustin

    2013-01-01

    The increasing rate of biological invasions resulting from human transport or human-mediated changes to the environment have had devastating ecologic and public health consequences. The kissing bug, Triatoma infestans, has dispersed through the Peruvian city of Arequipa. The biological invasion of this insect has resulted in a public health crisis, putting thousands of residents of this city at risk of infection by Trypanosoma cruzi and subsequent development of Chagas disease. Here we show that populations of Tria. Infestans in geographically distinct districts within and around this urban center share a common recent evolutionary history although current gene flow is restricted even between proximal sites. The population structure among the Tria. Infestans in different districts is not correlated with the geographic distance between districts. These data suggest that migration among the districts is mediated by factors beyond the short-range migratory capabilities of Tria. Infestans and that human movement has played a significant role in the structuring of the Tria. Infestans population in the region. Rapid urbanization across southern South America will continue to create suitable environments for Tria. Infestans and knowledge of its urban dispersal patterns may play a fundamental role in mitigating human disease risk. PMID:24103030

  20. Climate Change in the North American Arctic: A One Health Perspective.

    PubMed

    Dudley, Joseph P; Hoberg, Eric P; Jenkins, Emily J; Parkinson, Alan J

    2015-12-01

    Climate change is expected to increase the prevalence of acute and chronic diseases among human and animal populations within the Arctic and subarctic latitudes of North America. Warmer temperatures are expected to increase disease risks from food-borne pathogens, water-borne diseases, and vector-borne zoonoses in human and animal populations of Arctic landscapes. Existing high levels of mercury and persistent organic pollutant chemicals circulating within terrestrial and aquatic ecosystems in Arctic latitudes are a major concern for the reproductive health of humans and other mammals, and climate warming will accelerate the mobilization and biological amplification of toxic environmental contaminants. The adverse health impacts of Arctic warming will be especially important for wildlife populations and indigenous peoples dependent upon subsistence food resources from wild plants and animals. Additional research is needed to identify and monitor changes in the prevalence of zoonotic pathogens in humans, domestic dogs, and wildlife species of critical subsistence, cultural, and economic importance to Arctic peoples. The long-term effects of climate warming in the Arctic cannot be adequately predicted or mitigated without a comprehensive understanding of the interactive and synergistic effects between environmental contaminants and pathogens in the health of wildlife and human communities in Arctic ecosystems. The complexity and magnitude of the documented impacts of climate change on Arctic ecosystems, and the intimacy of connections between their human and wildlife communities, makes this region an appropriate area for development of One Health approaches to identify and mitigate the effects of climate warming at the community, ecosystem, and landscape scales.

  1. Environmental controls, oceanography and population dynamics of pathogens and harmful algal blooms: connecting sources to human exposure.

    PubMed

    Dyble, Julianne; Bienfang, Paul; Dusek, Eva; Hitchcock, Gary; Holland, Fred; Laws, Ed; Lerczak, James; McGillicuddy, Dennis J; Minnett, Peter; Moore, Stephanie K; O'Kelly, Charles; Solo-Gabriele, Helena; Wang, John D

    2008-11-07

    Coupled physical-biological models are capable of linking the complex interactions between environmental factors and physical hydrodynamics to simulate the growth, toxicity and transport of infectious pathogens and harmful algal blooms (HABs). Such simulations can be used to assess and predict the impact of pathogens and HABs on human health. Given the widespread and increasing reliance of coastal communities on aquatic systems for drinking water, seafood and recreation, such predictions are critical for making informed resource management decisions. Here we identify three challenges to making this connection between pathogens/HABs and human health: predicting concentrations and toxicity; identifying the spatial and temporal scales of population and ecosystem interactions; and applying the understanding of population dynamics of pathogens/HABs to management strategies. We elaborate on the need to meet each of these challenges, describe how modeling approaches can be used and discuss strategies for moving forward in addressing these challenges.

  2. Yak whole-genome resequencing reveals domestication signatures and prehistoric population expansions.

    PubMed

    Qiu, Qiang; Wang, Lizhong; Wang, Kun; Yang, Yongzhi; Ma, Tao; Wang, Zefu; Zhang, Xiao; Ni, Zhengqiang; Hou, Fujiang; Long, Ruijun; Abbott, Richard; Lenstra, Johannes; Liu, Jianquan

    2015-12-22

    Yak domestication represents an important episode in the early human occupation of the high-altitude Qinghai-Tibet Plateau (QTP). The precise timing of domestication is debated and little is known about the underlying genetic changes that occurred during the process. Here we investigate genome variation of wild and domestic yaks. We detect signals of selection in 209 genes of domestic yaks, several of which relate to behaviour and tameness. We date yak domestication to 7,300 years before present (yr BP), most likely by nomadic people, and an estimated sixfold increase in yak population size by 3,600 yr BP. These dates coincide with two early human population expansions on the QTP during the early-Neolithic age and the late-Holocene, respectively. Our findings add to an understanding of yak domestication and its importance in the early human occupation of the QTP.

  3. Yak whole-genome resequencing reveals domestication signatures and prehistoric population expansions

    PubMed Central

    Qiu, Qiang; Wang, Lizhong; Wang, Kun; Yang, Yongzhi; Ma, Tao; Wang, Zefu; Zhang, Xiao; Ni, Zhengqiang; Hou, Fujiang; Long, Ruijun; Abbott, Richard; Lenstra, Johannes; Liu, Jianquan

    2015-01-01

    Yak domestication represents an important episode in the early human occupation of the high-altitude Qinghai-Tibet Plateau (QTP). The precise timing of domestication is debated and little is known about the underlying genetic changes that occurred during the process. Here we investigate genome variation of wild and domestic yaks. We detect signals of selection in 209 genes of domestic yaks, several of which relate to behaviour and tameness. We date yak domestication to 7,300 years before present (yr BP), most likely by nomadic people, and an estimated sixfold increase in yak population size by 3,600 yr BP. These dates coincide with two early human population expansions on the QTP during the early-Neolithic age and the late-Holocene, respectively. Our findings add to an understanding of yak domestication and its importance in the early human occupation of the QTP. PMID:26691338

  4. Coral reef degradation is not correlated with local human population density

    NASA Astrophysics Data System (ADS)

    Bruno, John F.; Valdivia, Abel

    2016-07-01

    The global decline of reef-building corals is understood to be due to a combination of local and global stressors. However, many reef scientists assume that local factors predominate and that isolated reefs, far from human activities, are generally healthier and more resilient. Here we show that coral reef degradation is not correlated with human population density. This suggests that local factors such as fishing and pollution are having minimal effects or that their impacts are masked by global drivers such as ocean warming. Our results also suggest that the effects of local and global stressors are antagonistic, rather than synergistic as widely assumed. These findings indicate that local management alone cannot restore coral populations or increase the resilience of reefs to large-scale impacts. They also highlight the truly global reach of anthropogenic warming and the immediate need for drastic and sustained cuts in carbon emissions.

  5. Human adaptation and population differentiation in the light of ancient genomes

    PubMed Central

    Key, Felix M.; Fu, Qiaomei; Romagné, Frédéric; Lachmann, Michael; Andrés, Aida M.

    2016-01-01

    The influence of positive selection sweeps in human evolution is increasingly debated, although our ability to detect them is hampered by inherent uncertainties in the timing of past events. Ancient genomes provide snapshots of allele frequencies in the past and can help address this question. We combine modern and ancient genomic data in a simple statistic (DAnc) to time allele frequency changes, and investigate the role of drift and adaptation in population differentiation. Only 30% of the most strongly differentiated alleles between Africans and Eurasians changed in frequency during the colonization of Eurasia, but in Europe these alleles are enriched in genic and putatively functional alleles to an extent only compatible with local adaptation. Adaptive alleles—especially those associated with pigmentation—are mostly of hunter-gatherer origin, although lactose persistence arose in a haplotype present in farmers. These results provide evidence for a role of local adaptation in human population differentiation. PMID:26988143

  6. Coral reef degradation is not correlated with local human population density.

    PubMed

    Bruno, John F; Valdivia, Abel

    2016-07-20

    The global decline of reef-building corals is understood to be due to a combination of local and global stressors. However, many reef scientists assume that local factors predominate and that isolated reefs, far from human activities, are generally healthier and more resilient. Here we show that coral reef degradation is not correlated with human population density. This suggests that local factors such as fishing and pollution are having minimal effects or that their impacts are masked by global drivers such as ocean warming. Our results also suggest that the effects of local and global stressors are antagonistic, rather than synergistic as widely assumed. These findings indicate that local management alone cannot restore coral populations or increase the resilience of reefs to large-scale impacts. They also highlight the truly global reach of anthropogenic warming and the immediate need for drastic and sustained cuts in carbon emissions.

  7. Coral reef degradation is not correlated with local human population density

    PubMed Central

    Bruno, John F.; Valdivia, Abel

    2016-01-01

    The global decline of reef-building corals is understood to be due to a combination of local and global stressors. However, many reef scientists assume that local factors predominate and that isolated reefs, far from human activities, are generally healthier and more resilient. Here we show that coral reef degradation is not correlated with human population density. This suggests that local factors such as fishing and pollution are having minimal effects or that their impacts are masked by global drivers such as ocean warming. Our results also suggest that the effects of local and global stressors are antagonistic, rather than synergistic as widely assumed. These findings indicate that local management alone cannot restore coral populations or increase the resilience of reefs to large-scale impacts. They also highlight the truly global reach of anthropogenic warming and the immediate need for drastic and sustained cuts in carbon emissions. PMID:27435659

  8. The effects of spatial population dataset choice on estimates of population at risk of disease

    PubMed Central

    2011-01-01

    Background The spatial modeling of infectious disease distributions and dynamics is increasingly being undertaken for health services planning and disease control monitoring, implementation, and evaluation. Where risks are heterogeneous in space or dependent on person-to-person transmission, spatial data on human population distributions are required to estimate infectious disease risks, burdens, and dynamics. Several different modeled human population distribution datasets are available and widely used, but the disparities among them and the implications for enumerating disease burdens and populations at risk have not been considered systematically. Here, we quantify some of these effects using global estimates of populations at risk (PAR) of P. falciparum malaria as an example. Methods The recent construction of a global map of P. falciparum malaria endemicity enabled the testing of different gridded population datasets for providing estimates of PAR by endemicity class. The estimated population numbers within each class were calculated for each country using four different global gridded human population datasets: GRUMP (~1 km spatial resolution), LandScan (~1 km), UNEP Global Population Databases (~5 km), and GPW3 (~5 km). More detailed assessments of PAR variation and accuracy were conducted for three African countries where census data were available at a higher administrative-unit level than used by any of the four gridded population datasets. Results The estimates of PAR based on the datasets varied by more than 10 million people for some countries, even accounting for the fact that estimates of population totals made by different agencies are used to correct national totals in these datasets and can vary by more than 5% for many low-income countries. In many cases, these variations in PAR estimates comprised more than 10% of the total national population. The detailed country-level assessments suggested that none of the datasets was consistently more accurate than the others in estimating PAR. The sizes of such differences among modeled human populations were related to variations in the methods, input resolution, and date of the census data underlying each dataset. Data quality varied from country to country within the spatial population datasets. Conclusions Detailed, highly spatially resolved human population data are an essential resource for planning health service delivery for disease control, for the spatial modeling of epidemics, and for decision-making processes related to public health. However, our results highlight that for the low-income regions of the world where disease burden is greatest, existing datasets display substantial variations in estimated population distributions, resulting in uncertainty in disease assessments that utilize them. Increased efforts are required to gather contemporary and spatially detailed demographic data to reduce this uncertainty, particularly in Africa, and to develop population distribution modeling methods that match the rigor, sophistication, and ability to handle uncertainty of contemporary disease mapping and spread modeling. In the meantime, studies that utilize a particular spatial population dataset need to acknowledge the uncertainties inherent within them and consider how the methods and data that comprise each will affect conclusions. PMID:21299885

  9. Dengue virus in sub-tropical northern and central Viet Nam: population immunity and climate shape patterns of viral invasion and maintenance.

    PubMed

    Rabaa, Maia A; Simmons, Cameron P; Fox, Annette; Le, Mai Quynh; Nguyen, Thuy Thi Thu; Le, Hai Yen; Gibbons, Robert V; Nguyen, Xuyen Thanh; Holmes, Edward C; Aaskov, John G

    2013-01-01

    Dengue virus transmission occurs in both epidemic and endemic cycles across tropical and sub-tropical regions of the world. Incidence is particularly high in much of Southeast Asia, where hyperendemic transmission plagues both urban and rural populations. However, endemicity has not been established in some areas with climates that may not support year-round viral transmission. An understanding of how dengue viruses (DENV) enter these environments and whether the viruses persist in inapparent local transmission cycles is central to understanding how dengue emerges in areas at the margins of endemic transmission. Dengue is highly endemic in tropical southern Vietnam, while increasingly large seasonal epidemics have occurred in northern Viet Nam over the last decade. We have investigated the spread of DENV-1 throughout Vietnam to determine the routes by which the virus enters northern and central regions of the country. Phylogeographic analysis of 1,765 envelope (E) gene sequences from Southeast Asia revealed frequent movement of DENV between neighboring human populations and strong local clustering of viral lineages. Long-distance migration of DENV between human population centers also occurred regularly and on short time-scales, indicating human-mediated viral invasion into northern Vietnam. Human populations in southern Vietnam were found to be the primary source of DENV circulating throughout the country, while central and northern Vietnam acted as sink populations, likely due to reduced connectedness to other populations in the case of the central regions and to the influence of temperature variability on DENV replication and vector survival and competence in the north. Finally, phylogeographic analyses suggested that viral movement follows a gravity model and indicates that population immunity and physical and economic connections between populations may play important roles in shaping patterns of DENV transmission.

  10. Dengue Virus in Sub-tropical Northern and Central Viet Nam: Population Immunity and Climate Shape Patterns of Viral Invasion and Maintenance

    PubMed Central

    Rabaa, Maia A.; Simmons, Cameron P.; Fox, Annette; Le, Mai Quynh; Nguyen, Thuy Thi Thu; Le, Hai Yen; Gibbons, Robert V.; Nguyen, Xuyen Thanh; Holmes, Edward C.; Aaskov, John G.

    2013-01-01

    Dengue virus transmission occurs in both epidemic and endemic cycles across tropical and sub-tropical regions of the world. Incidence is particularly high in much of Southeast Asia, where hyperendemic transmission plagues both urban and rural populations. However, endemicity has not been established in some areas with climates that may not support year-round viral transmission. An understanding of how dengue viruses (DENV) enter these environments and whether the viruses persist in inapparent local transmission cycles is central to understanding how dengue emerges in areas at the margins of endemic transmission. Dengue is highly endemic in tropical southern Vietnam, while increasingly large seasonal epidemics have occurred in northern Viet Nam over the last decade. We have investigated the spread of DENV-1 throughout Vietnam to determine the routes by which the virus enters northern and central regions of the country. Phylogeographic analysis of 1,765 envelope (E) gene sequences from Southeast Asia revealed frequent movement of DENV between neighboring human populations and strong local clustering of viral lineages. Long-distance migration of DENV between human population centers also occurred regularly and on short time-scales, indicating human-mediated viral invasion into northern Vietnam. Human populations in southern Vietnam were found to be the primary source of DENV circulating throughout the country, while central and northern Vietnam acted as sink populations, likely due to reduced connectedness to other populations in the case of the central regions and to the influence of temperature variability on DENV replication and vector survival and competence in the north. Finally, phylogeographic analyses suggested that viral movement follows a gravity model and indicates that population immunity and physical and economic connections between populations may play important roles in shaping patterns of DENV transmission. PMID:24340118

  11. Population and development.

    PubMed

    Rao, S V

    1992-01-01

    A unified approach to development is recommended: one in which the social, economic, and political components are accounted for within a multidimensional process of reorganization and reorientation of structures and attitudes, customs, and beliefs. During the 1970s, development was construed as improvement in employment within a growing economy and elimination of poverty and inequality--a redistribution of growth. Development should increase and widen the distribution of basic life sustaining goods, increase levels of living, and expand economic and social choices and free people from dependence on other people and servitude to ignorance and poverty. Six basic issues linking population growth and development were identified; the interrelationships between economic, social, and demographic variables were explained. The aims of educational development and educational progress as affected by urbanization were discussed. It is inappropriate to isolate economic, social, and demographic concerns as separate entities and as separate from the development process. The population problem of rapid population growth is intertwined with the problem of unmet human needs; problematic are illiteracy, extreme deprivation, insufficient income to purchase essential health services and basic nutrition, and inadequate diets. Improvements have not kept pace with needs. The theories of Malthus are no longer germane, and demographic transition theory is not as effective in achieving or explaining the reduction of birth rates. An approach which attacks poverty and low quality of life would be directed to core motivations. The hidden momentum of population growth and the impact of literacy and age and sex composition are discussed as features of improvement in quality of life and of fertility reduction. Economic and social development are dependent on human resources, not on capital or material resources. The institutional mechanism for developing human potential is the educational system. Even though enrollments have increased over the past 30 years, employment opportunities and standard of living have not changed markedly. India was given as an example of the dynamics of facilities management. Education also impacts on fertility and is affected by the distribution of the population.

  12. Managing individual nests promotes population recovery of a top predator

    USGS Publications Warehouse

    Cruz, Jennyffer; Windels, Steve K.; Thogmartin, Wayne E.; Crimmins, Shawn M.; Grim, Leland; Zuckerberg, Benjamin

    2018-01-01

    Threatened species are managed using diverse conservation tactics implemented at multiple scales ranging from protecting individuals, to populations, to entire species. Individual protection strives to promote recovery at the population‐ or species‐level, although this is seldom evaluated.After decades of widespread declines, bald eagles, Haliaeetus leucocephalus, are recovering throughout their range due to legal protection and pesticide bans. However, like other raptors, their recovery remains threatened by human activities. Bald eagle nests are commonly managed using buffer zones to minimize human disturbance, but the benefits of this practice remain unquantified.Within Voyageurs National Park (VNP), Minnesota, USA, managers have monitored bald eagle populations for over 40 years, and since 1991, have protected at‐risk nests from human disturbance using buffer zones (200 and 400 m radius). We aimed to (1) quantify the recovery of bald eagles in VNP (1973–2016), and (2) provide a first‐ever evaluation of the individual‐ and population‐level effects of managing individual nests. To do so, we developed Bayesian Integrated Population Models combining observations of nest occupancy and reproductive output (metrics commonly collected for raptors) to estimate nest‐level probabilities of occupancy, nest success, and high productivity (producing ≥2 nestlings), as well as population‐level estimates of abundance and growth.The breeding population of bald eagles at VNP increased steadily from <10 pairs in the late 1970s to 48 pairs by 2016. At the nest‐level, management significantly improved occupancy and success. At the population‐level, management led to 8% and 13% increases in nest success and productivity rates, respectively, resulting in a 37% increase in breeding pair abundance.Synthesis and applications. There is a clear need to evaluate how management approaches at multiple scales assist in species recovery. Our study uses an Integrated Population Model to reveal the population‐level benefits of a widely used, individual‐based management action (protecting nests using buffer zones) on a recovering raptor.

  13. Quantifying the increase in average human heterozygosity due to urbanisation.

    PubMed

    Rudan, Igor; Carothers, Andrew D; Polasek, Ozren; Hayward, Caroline; Vitart, Veronique; Biloglav, Zrinka; Kolcic, Ivana; Zgaga, Lina; Ivankovic, Davor; Vorko-Jovic, Ariana; Wilson, James F; Weber, James L; Hastie, Nick; Wright, Alan; Campbell, Harry

    2008-09-01

    The human population is undergoing a major transition from a historical metapopulation structure of relatively isolated small communities to an outbred structure. This process is predicted to increase average individual genome-wide heterozygosity (h) and could have effects on health. We attempted to quantify this increase in mean h. We initially sampled 1001 examinees from a metapopulation of nine isolated villages on five Dalmatian islands (Croatia). Village populations had high levels of genetic differentiation, endogamy and consanguinity. We then selected 166 individuals with highly specific personal genetic histories to form six subsamples, which could be ranked a priori by their predicted level of outbreeding. The measure h was then estimated in the 166 examinees by genotyping 1184 STR/indel markers and using two different computation methods. Compared to the value of mean h in the least outbred sample, values of h in the remaining samples increased successively with predicted outbreeding by 0.023, 0.038, 0.058, 0.067 and 0.079 (P<0.0001), where these values are measured on the same scale as the inbreeding coefficient (but opposite sign). We have shown that urbanisation was associated with an average increase in h of up to 0.08-0.10 in this Croatian metapopulation, regardless of the method used. Similar levels of differentiation have been described in many populations. Therefore, changes in the level of heterozygosity across the genome of this magnitude may be common during isolate break-up in humans and could have significant health effects through the established genetic mechanism of hybrid vigour/heterosis.

  14. Mercury transport and human exposure from global marine fisheries.

    PubMed

    Lavoie, Raphael A; Bouffard, Ariane; Maranger, Roxane; Amyot, Marc

    2018-04-30

    Human activities have increased the global circulation of mercury, a potent neurotoxin. Mercury can be converted into methylmercury, which biomagnifies along aquatic food chains and leads to high exposure in fish-eating populations. Here we quantify temporal trends in the ocean-to-land transport of total mercury and methylmercury from fisheries and we estimate potential human mercury intake through fish consumption in 175 countries. Mercury export from the ocean increased over time as a function of fishing pressure, especially on upper-trophic-level organisms. In 2014, over 13 metric tonnes of mercury were exported from the ocean. Asian countries were important contributors of mercury export in the last decades and the western Pacific Ocean was identified as the main source. Estimates of per capita mercury exposure through fish consumption showed that populations in 38% of the 175 countries assessed, mainly insular and developing nations, were exposed to doses of methylmercury above governmental thresholds. Our study shows temporal trends and spatial patterns of Hg transport by fisheries. Given the high mercury intake through seafood consumption observed in several understudied yet vulnerable coastal communities, we recommend a comprehensive assessment of the health exposure risk of those populations.

  15. Human behaviour can trigger large carnivore attacks in developed countries

    PubMed Central

    Penteriani, Vincenzo; Delgado, María del Mar; Pinchera, Francesco; Naves, Javier; Fernández-Gil, Alberto; Kojola, Ilpo; Härkönen, Sauli; Norberg, Harri; Frank, Jens; Fedriani, José María; Sahlén, Veronica; Støen, Ole-Gunnar; Swenson, Jon E.; Wabakken, Petter; Pellegrini, Mario; Herrero, Stephen; López-Bao, José Vicente

    2016-01-01

    The media and scientific literature are increasingly reporting an escalation of large carnivore attacks on humans in North America and Europe. Although rare compared to human fatalities by other wildlife, the media often overplay large carnivore attacks on humans, causing increased fear and negative attitudes towards coexisting with and conserving these species. Although large carnivore populations are generally increasing in developed countries, increased numbers are not solely responsible for the observed rise in the number of attacks by large carnivores. Here we show that an increasing number of people are involved in outdoor activities and, when doing so, some people engage in risk-enhancing behaviour that can increase the probability of a risky encounter and a potential attack. About half of the well-documented reported attacks have involved risk-enhancing human behaviours, the most common of which is leaving children unattended. Our study provides unique insight into the causes, and as a result the prevention, of large carnivore attacks on people. Prevention and information that can encourage appropriate human behaviour when sharing the landscape with large carnivores are of paramount importance to reduce both potentially fatal human-carnivore encounters and their consequences to large carnivores. PMID:26838467

  16. Human behaviour can trigger large carnivore attacks in developed countries.

    PubMed

    Penteriani, Vincenzo; Delgado, María del Mar; Pinchera, Francesco; Naves, Javier; Fernández-Gil, Alberto; Kojola, Ilpo; Härkönen, Sauli; Norberg, Harri; Frank, Jens; Fedriani, José María; Sahlén, Veronica; Støen, Ole-Gunnar; Swenson, Jon E; Wabakken, Petter; Pellegrini, Mario; Herrero, Stephen; López-Bao, José Vicente

    2016-02-03

    The media and scientific literature are increasingly reporting an escalation of large carnivore attacks on humans in North America and Europe. Although rare compared to human fatalities by other wildlife, the media often overplay large carnivore attacks on humans, causing increased fear and negative attitudes towards coexisting with and conserving these species. Although large carnivore populations are generally increasing in developed countries, increased numbers are not solely responsible for the observed rise in the number of attacks by large carnivores. Here we show that an increasing number of people are involved in outdoor activities and, when doing so, some people engage in risk-enhancing behaviour that can increase the probability of a risky encounter and a potential attack. About half of the well-documented reported attacks have involved risk-enhancing human behaviours, the most common of which is leaving children unattended. Our study provides unique insight into the causes, and as a result the prevention, of large carnivore attacks on people. Prevention and information that can encourage appropriate human behaviour when sharing the landscape with large carnivores are of paramount importance to reduce both potentially fatal human-carnivore encounters and their consequences to large carnivores.

  17. Assessing increasing susceptibility to wildfire at the wildland-urban fringe in the western United States

    NASA Astrophysics Data System (ADS)

    Kinoshita, A. M.; Hogue, T. S.

    2013-05-01

    Much of the western U.S. is increasingly susceptible to wildfire activity due to drier conditions, elevated fuel loads, and expanding urbanization. As population increases, development pushes the urban boundary further into wildlands, creating more potential for human interaction at the wildland-urban interface (WUI), primarily from human ignitions and fire suppression policies. The immediate impacts of wildfires include vulnerability to debris flows, flooding, and impaired water quality. Fires also alter longer-term hydrological and ecosystem behavior. The current study utilizes geospatial datasets to investigate historical wildfire size and frequency relative to the WUI for a range of cities across western North America. California, the most populous state in the U.S., has an extensive fire history. The decennial population and acres burned for four major counties (Los Angeles, San Bernardino, San Diego, and Shasta) in California show that increasing wildfire size and frequency follow urbanization trends, with high correlation between the last decade of burned area, urban-fringe proximity, and increasing population. Ultimately, results will provide information on urban fringe communities that are most vulnerable to the risks associated with wildfire and post-fire impacts. In light of evolving land use policies (i.e. forest management and treatment, development at the urban-fringe) and climate change, it is critical to advance our knowledge of the implications that these conditions pose to urban centers, communicate risks to the public, and ultimately provide guidance for wildfire management.

  18. Dust and human health: Chapter 15

    USGS Publications Warehouse

    Morman, Suzette A.; Plumlee, Geoffrey S.; Knippertz, Peter; Stuut, Jan-Berend W.

    2013-01-01

    It is generally accepted that exposure to fine particulate matter may increase risk for human morbidity and mortality. Until recently, population health related studies examining the effects of particulate matter on human health generally examined anthropogenic (industry and combustion by-products) sources with few studies considering contributions from natural sources. This chapter provides an overview of naturally occurring inorganic mineral dust research and associated human health ailments and some of the challenges in elucidating the etiological mechanisms responsible.

  19. No choice. Human beings must continue to be fertile and to increase, but they must do so responsibly.

    PubMed

    Tagle Ra

    1993-06-01

    Commentary is provided on the transition mankind has made from a maintained population growth rate of 2% to adaptation to a more civilized age. When the agricultural age began 100,000 years ago, man was still tribal, and it may well be that scientists are correct in postulating that adaptation is slow. Homo sapiens are still tribal or tried to family or kin groups, rather than to the nations state. These ties to family and tribe may contribute to present day "ethnic cleansing" and the illusion of the notion of a family of all peoples. In the past, families had to be large in order to sustain life; there was still a high death rate which slowed population growth. Population reached 2 billion in 1930 after a million years of growth. Mankind's tinkering with nature produced science and technology, which eliminated the natural balance of mortality. The consequence was a doubling of population in 47 years between 1930 to 1977 to 4 billion people. BY 1987, in just 10 years, another billion was added. Homo sapiens must not act responsible and influence the birth side by practicing "contraception control." Unfortunately, the force of habit has obliterated the reasons for large families, and humans have "unwittingly defied procreation from being merely a means to the status of an end." There is nothing in the Bible that forbids contraception or mentions multiplying in an irresponsible way. Neither this vast increase in population, which presently grows at 95 million per year, nor scientific advancement has eliminated mortality or disease. Million suffer from malnutrition and starvation, and the distribution of resources has been unequal and moves in the direction of resource depletion and environmental degradation. The formula for living must change; families need to plan for few children. Fighting to kill as a means of population control is unacceptable. Human beings possess the intelligence to preserve individual and social human life in a responsible way.

  20. Implications of global climate change for housing, human settlements and public health.

    PubMed

    Hales, Simon; Baker, Michael; Howden-Chapman, Philippa; Menne, Bettina; Woodruff, Rosalie; Woodward, Alistair

    2007-01-01

    Global climate change has profound implications for human societies. The present---ecologically unsustainable--trajectory of human development fails to provide for the basic needs of a substantial fraction of the global population, while diminishing the prospects for future generations. Human-caused climate change has already begun to affect weather patterns, physical and biological phenomena, and vulnerable human communities. Because the social processes of production and consumption have their own momentum, and because carbon dioxide has a long atmospheric lifetime, further climate change is inevitable over the coming century, even allowing for the adoption of mitigation measures. This situation implies that we should also try to reduce, and where possible to prevent, the adverse effects of climate changes by planned adaptation. Will human settlements be able to provide a healthy living environment and shelter from extreme climate events, such as cyclones and heat waves? In this paper, we review the nexus between human health, climate change, and the planning of housing and human settlements. We conclude that adapting to a rapidly changing global environment will be a major challenge, in the context of increasing population and per capita consumption, without increasing pressures on natural systems. Energy-efficient cities and the creation of opportunities for poor countries will be important elements of people centered, ecologically sustainable, development in the twenty-first century.

  1. Linking Glaciochemical and Historical Evidence to Study the Impact of Climate Change and Air Pollution on Human Populations in the Last Millennium

    NASA Astrophysics Data System (ADS)

    More, A.; Chaplin, J. E.

    2017-12-01

    A transdisciplinary approach to study the impact of climate change and air pollution has already yielded significant results, where the detail afforded by historical records has linked glaciochemical data with major economic, epidemiological and climatic events (e.g. More et al., Geohealth, 2017). Historical data has allowed for more accurate calibration of ice-core chronologies, reaching sub-annual accuracy. In turn, more precise chronologies and higher resolution glaciochemical data has added a new dimension to our understanding of the environment and human experience in the last millennium of the Common Era. In this paper we propose examples of the benefits of linking highly detailed and large historical datasets with ultra-high-resolution glaciochemical data obtained through laser ablation, inductively coupled mass spectrometry. We will first examine the signature left in the ice-core record by documented, catastrophic epidemiological and economic events. Epidemics reduced population size, thus affecting economic productivity and therefore atmospheric pollution, especially from labor intensive activities such as the mining of metals (copper, iron, silver, lead), or the consumption of firewood. We will then turn our attention to the impact of increased precipitation and severe climate change on human subsistence and stability. We link glaciochemical signals associated with increased precipitation and temperature decreases with multiple, large datasets of historical records of population collapse and increased civil strife in the middle of the Little Ice Age. In particular, we will focus on how in concomitance with severe climate deterioration European countries began prosecuting citizens—by the thousands—for crimes associated with poor harvests. These prosecutions were often the result of an increase in baseless accusations of supernatural influences of thousands of individuals on phenomena such as incessant rain, unseasonal temperature decreases, frosts, and droughts. This paper will thus show the human impact on the atmosphere's composition and the impact of atmospheric conditions on human behavior, serving as a template for understanding similar reactions to severe climate change in the present.

  2. The Human Impact of Tropical Cyclones: a Historical Review of Events 1980-2009 and Systematic Literature Review

    PubMed Central

    Doocy, Shannon; Dick, Anna; Daniels, Amy; Kirsch, Thomas D.

    2013-01-01

    Background. Cyclones have significantly affected populations in Southeast Asia, the Western Pacific, and the Americas over the past quarter of a century. Future vulnerability to cyclones will increase due to factors including population growth, urbanization, increasing coastal settlement, and global warming. The objectives of this review were to describe the impact of cyclones on human populations in terms of mortality, injury, and displacement and, to the extent possible, identify risk factors associated with these outcomes. This is one of five reviews on the human impact of natural disasters. Methods. Data on the impact of cyclones were compiled using two methods, a historical review from 1980 to 2009 of cyclone events from multiple databases and a systematic literature review of publications ending in October 2012. Analysis included descriptive statistics and bivariate tests for associations between cyclone characteristics and mortality using Stata 11.0. Findings. There were 412,644 deaths, 290,654 injured, and 466.1 million people affected by cyclones between 1980 and 2009, and the mortality and injury burden was concentrated in less developed nations of Southeast Asia and the Western Pacific. Inconsistent reporting suggests this is an underestimate, particularly in terms of the injured and affected populations. The primary cause of cyclone-related mortality is drowning; in developed countries male gender was associated with increased mortality risk, whereas females experienced higher mortality in less developed countries. Conclusions. Additional attention to preparedness and early warning, particularly in Asia, can lessen the impact of future cyclones. PMID:23857074

  3. Emerging avenues for utilization of exotic germplasm

    USDA-ARS?s Scientific Manuscript database

    Breeders have been successful in increasing crop performance by exploiting genetic diversity over time. However, the reported annual yield increases are not sufficient in view of rapid human population growth and global environmental changes. Exotic germplasm such as landraces and wild relatives pos...

  4. The Genetic Cost of Neanderthal Introgression

    PubMed Central

    Harris, Kelley; Nielsen, Rasmus

    2016-01-01

    Approximately 2–4% of genetic material in human populations outside Africa is derived from Neanderthals who interbred with anatomically modern humans. Recent studies have shown that this Neanderthal DNA is depleted around functional genomic regions; this has been suggested to be a consequence of harmful epistatic interactions between human and Neanderthal alleles. However, using published estimates of Neanderthal inbreeding and the distribution of mutational fitness effects, we infer that Neanderthals had at least 40% lower fitness than humans on average; this increased load predicts the reduction in Neanderthal introgression around genes without the need to invoke epistasis. We also predict a residual Neanderthal mutational load in non-Africans, leading to a fitness reduction of at least 0.5%. This effect of Neanderthal admixture has been left out of previous debate on mutation load differences between Africans and non-Africans. We also show that if many deleterious mutations are recessive, the Neanderthal admixture fraction could increase over time due to the protective effect of Neanderthal haplotypes against deleterious alleles that arose recently in the human population. This might partially explain why so many organisms retain gene flow from other species and appear to derive adaptive benefits from introgression. PMID:27038113

  5. The role of anthropometry in designing for sustainability.

    PubMed

    Nadadur, Gopal; Parkinson, Matthew B

    2013-01-01

    An understanding of human factors and ergonomics facilitates the design of artefacts, tasks and environments that fulfil their users' physical and cognitive requirements. Research in these fields furthers the goal of efficiently accommodating the desired percentage of user populations through enhanced awareness and modelling of human variability. Design for sustainability (DfS) allows for these concepts to be leveraged in the broader context of designing to minimise negative impacts on the environment. This paper focuses on anthropometry and proposes three ways in which its consideration is relevant to DfS: reducing raw material consumption, increasing usage lifetimes and ethical human resource considerations. This is demonstrated through the application of anthropometry synthesis, virtual fitting, and sizing and adjustability allocation methods in the design of an industrial workstation seat for use in five distinct global populations. This work highlights the importance of and opportunities for using ergonomic design principles in DfS efforts. This research demonstrates the relevance of some anthropometry-based ergonomics concepts to the field of design for sustainability. A global design case study leverages human variability considerations in furthering three sustainable design goals: reducing raw material consumption, increasing usage lifetimes and incorporating ethical human resource considerations in design.

  6. Emerging Chagas disease: trophic network and cycle of transmission of Trypanosoma cruzi from palm trees in the Amazon.

    PubMed Central

    Teixeira, A. R.; Monteiro, P. S.; Rebelo, J. M.; Argañaraz, E. R.; Vieira, D.; Lauria-Pires, L.; Nascimento, R.; Vexenat, C. A.; Silva, A. R.; Ault, S. K.; Costa, J. M.

    2001-01-01

    A trophic network involving molds, invertebrates, and vertebrates, ancestrally adapted to the palm tree (Attalaea phalerata) microhabitat, maintains enzootic Trypanosoma cruzi infections in the Amazonian county Paço do Lumiar, state of Maranhão, Brazil. We assessed seropositivity for T. cruzi infections in the human population of the county, searched in palm trees for the triatomines that harbor these infections, and gathered demographic, environmental, and socioeconomic data. Rhodnius pictipes and R. neglectus in palm-tree frond clefts or in houses were infected with T. cruzi (57% and 41%, respectively). Human blood was found in 6.8% of R. pictipes in houses, and 9 of 10 wild Didelphis marsupialis had virulent T. cruzi infections. Increasing human population density, rain forest deforestation, and human predation of local fauna are risk factors for human T. cruzi infections. PMID:11266300

  7. Impact of quadrivalent human papillomavirus vaccine in women at increased risk of genital warts burden: Population-based cross-sectional survey of Czech women aged 16 to 40 years.

    PubMed

    Petráš, Marek; Adámková, Věra

    2015-11-17

    To assess the impact of a quadrivalent human papillomavirus vaccine (4HPV) in women at increased risk of genital warts (GWs) acquisition. The study was conducted using a population-based cross-sectional survey of 19,199 women aged 16 to 40 years randomly chosen from the general population in the Czech Republic between January 2013 and March 2014. A total of 1086 women reported having received the 4HPV vaccine. The vaccine's effectiveness was estimated not only in the general population of women but also in those at increased risk due to having a sexual partner with GWs or prior GWs history. The acquisition of GWs was dramatically reduced by 90.6% (80.1-95.6%) in immunised women at least one year after the completion of the 4HPV vaccination in comparison with unimmunised women. Recurrent GWs prevalences of 1.1% (95% CI, 0.0-5.9) and 10.9% (95% CI, 9.1-12.9) in immunised and unimmunised women with prior GWs history, respectively, resulted in a vaccine effectiveness of 89.0% (38.6-98.0%). The notably strong protective effect of 4HPV immunisation in women who had a sexual partner with GWs was demonstrated by a very low age-adjusted odds ratio of 0.02 (95% CI 0.01-0.10) in contrast to unimmunised women. To lower the chance of genital warts acquisition in the general population and in populations at increased risk, only current 4HPV or incoming 9HPV vaccination should be recommended to provide effective protection. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Strategic Intervention of ODL in Bangladesh

    ERIC Educational Resources Information Center

    Rashid, A. Q. M. Bazlur; Rahman, M. Rokibur

    2010-01-01

    Education has been considered as a priority sector and a great challenge to the Bangladesh Government, with a view to transforming human potential into a productive workforce. The conventional face to face education system is not enough to cope with the need of an ever increasing population, rapid changes in human knowledge and the global context…

  9. Urban Green Space and Its Impact on Human Health

    Treesearch

    Michelle Kondo; Jaime Fluehr; Thomas McKeon; Charles Branas

    2018-01-01

    Background: Over half of the world's population now lives in urban areas, and this proportion is expected to increase. While there have been numerous reviews of empirical studies on the link between nature and human health, very few have focused on the urban context, and most have examined almost exclusively cross-sectional research. This...

  10. Delivering Human Services to the Rural Elderly: Implications From Research.

    ERIC Educational Resources Information Center

    Kerckhoff, Richard K.; Coward, Raymond T.

    Consistent with the national population growth pattern for nonmetropolitan areas, demographers have identified a significant shift in the residence of persons 65 years or older. In conjunction with an increased awareness of the discrepancy between the availability of human services for the elderly in urban and rural communities, establishment of a…

  11. Biodiversity and the exotic species threat

    Treesearch

    Peter S. White

    1998-01-01

    Exotic species invasions, called by one conservation biologist the "least reversible" of all human impacts, cause harm to economies (e.g., fisheries, wildlife populations, tourism), the environment (e.g., in the form of broadcast of pesticides and herbicides), human health and wellbeing (e.g., allergic responses and the increase in fire severity in some...

  12. IMPORTANT FACTORS CONCERNING HUMAN RESOURCES IN MISSISSIPPI. PRELIMINARY REPORT NUMBER 11.

    ERIC Educational Resources Information Center

    WALL, JAMES E.

    THE MORE IMPORTANT CHARACTERISTICS OF THE STATE'S HUMAN RESOURCES AND INFORMATION CONCERNING VOCATIONAL EDUCATION PROGRAMS ARE PRESENTED. MISSISSIPPI'S POPULATION INCREASED 21.6 PERCENT BETWEEN 1920 AND 1960. CENSUS DATA INDICATED (1) BIRTH RATES ARE HIGHER THAN NATIONAL AVERAGE, (2) DEATH RATES ARE CLOSE TO THE NATIONAL AVERAGE, (3) THE SHIFT…

  13. Sea-Level Rise and Land Subsidence in Deltas: Estimating Future Flood Risk Through Integrated Natural and Human System Modeling

    NASA Astrophysics Data System (ADS)

    Tessler, Z. D.; Vorosmarty, C. J.

    2016-12-01

    Deltas are highly sensitive to local human activities, land subsidence, regional water management, global sea-level rise, and climate extremes. We present a new delta flood exposure and risk framework for estimating the sensitivity of deltas to relative sea-level rise. We have applied this framework to a set of global environmental, geophysical, and social indicators over 48 major river deltas to quantify how contemporary risks vary across delta systems. The risk modeling framework incorporates upstream sediment flux and coastal land subsidence models, global empirical estimates of contemporary storm surge exposure, and population distribution and growth. Future scenarios are used to test the impacts on coastal flood risk of upstream dam construction, coastal population growth, accelerated sea-level rise, and enhanced storm surge. Results suggest a wide range of outcomes across different delta systems within each scenario. Deltas in highly engineered watersheds (Mississippi, Rhine) exhibit less sensitivity to increased dams due to saturation of sediment retention effects, though planned or under-construction dams are expected to have a substantial impact in the Yangtze, Irrawaddy, and Magdalena deltas. Population growth and sea-level rise are expected to be the dominant drivers of increased human risk in most deltas, with important exceptions in several countries, particularly China, where population are forecast to contract over the next several decades.

  14. Urbane Hydrogeologie - Herausforderungen für Forschung und Praxis

    NASA Astrophysics Data System (ADS)

    Schirmer, M.; Strauch, G.; Reinstorf, F.; Schirmer, K.

    2007-09-01

    Urban areas are a focus of increasing conflict with regard to water use and water protection. Half of the world’s population and about 73 % of Europeans live in cities. Currently, about 82 % of the total population growth of the world occurs in the cities of the developing countries (UN 2004). As a direct and/or indirect consequence of human activity, urban water systems are frequently polluted with organic contaminants. Many of these contaminants are related to human behaviour and activity, such as pharmaceuticals, personal care products (collectively PPCPs) and endocrine-active substances, and are increasingly found in urban water systems. However, the behaviour and the effects of these contaminants in the environment have been widely unknown until now. Consequently, it is important to pay more attention to such substances and to explore new integrated methodologies (including flux calculations as well as chemical and biological investigations) for determining the impact of human activities on urban water systems and on processes within the urban watershed. The overall goal is to assess the risks to humans and the ecosystem, and to support the development of suitable management strategies.

  15. Distant storms as drivers of environmental change at Pacific atolls.

    PubMed

    Gardner, Jonathan P A; Garton, David W; Collen, John D; Zwartz, Daniel

    2014-01-01

    The central Pacific Ocean with its many low lying islands and atolls is under threat from sea level rise and increased storm activity. Here, we illustrate how increasing frequency and severity of large scale storm events associated with global climate change may be particularly profound at the local scale for human populations that rely on lagoon systems for provision of a variety of goods and services. In August 2011 a storm originating in the Southern Ocean caused a large amplitude ocean swell to move northward through the Pacific Ocean. Its arrival at Palmyra Atoll coincided with transient elevated sea surface height and triggered turnover of the lagoon water column. This storm-induced change to the lagoon reflects long distance connectivity with propagated wave energy from the Southern Ocean and illustrates the increasing threats generated by climate change that are faced by human populations on most low-lying Pacific islands and atolls.

  16. Distant Storms as Drivers of Environmental Change at Pacific Atolls

    PubMed Central

    Gardner, Jonathan P. A.; Garton, David W.; Collen, John D.; Zwartz, Daniel

    2014-01-01

    The central Pacific Ocean with its many low lying islands and atolls is under threat from sea level rise and increased storm activity. Here, we illustrate how increasing frequency and severity of large scale storm events associated with global climate change may be particularly profound at the local scale for human populations that rely on lagoon systems for provision of a variety of goods and services. In August 2011 a storm originating in the Southern Ocean caused a large amplitude ocean swell to move northward through the Pacific Ocean. Its arrival at Palmyra Atoll coincided with transient elevated sea surface height and triggered turnover of the lagoon water column. This storm-induced change to the lagoon reflects long distance connectivity with propagated wave energy from the Southern Ocean and illustrates the increasing threats generated by climate change that are faced by human populations on most low-lying Pacific islands and atolls. PMID:24498232

  17. Over the hills and further away from coast: global geospatial patterns of human and environment over the 20th-21st centuries

    NASA Astrophysics Data System (ADS)

    Kummu, Matti; de Moel, Hans; Salvucci, Gianluigi; Viviroli, Daniel; Ward, Philip J.; Varis, Olli

    2016-03-01

    Proximity to the coast and elevation are important geographical considerations for human settlement. Little is known, however, about how spatial variation in these factors exactly relates to human settlements and activities, and how this has developed over time. Such knowledge is important for identifying vulnerable regions that are at risk from phenomena such as food shortages and water stress. Human activities are a key driving force in global change, and thus detailed information on population distribution is an important input to any research framework on global change. In this paper we assess the global geospatial patterns of the distribution of human population and related factors, with regard to the altitude above sea level and proximity to the coast. The investigated factors are physical conditions, urbanisation, agricultural practices, economy, and environmental stress. An important novel element in this study, is that we included the temporal evolution in various factors related to human settlements and agricultural practices over the 20th century, and used projections for some of these factors up to the year 2050. We found population pressure in the proximity of the coast to be somewhat greater than was found in other studies. Yet, the distribution of population, urbanisation and wealth are evolving to become more evenly spread across the globe than they were in the past. Therefore, the commonly believed tendency of accumulation of people and wealth along coasts is not supported by our results. At the same time, food production is becoming increasingly decoupled from the trends in population density. Croplands are spreading from highly populated coastal zones towards inland zones. Our results thus indicate that even though people and wealth continue to accumulate in proximity to the coast, population densities and economic productivity are becoming less diverse in relation to elevation and distance from the coast.

  18. Sixteen years of change in the global terrestrial human footprint and implications for biodiversity conservation

    NASA Astrophysics Data System (ADS)

    Venter, Oscar; Sanderson, Eric W.; Magrach, Ainhoa; Allan, James R.; Beher, Jutta; Jones, Kendall R.; Possingham, Hugh P.; Laurance, William F.; Wood, Peter; Fekete, Balázs M.; Levy, Marc A.; Watson, James E. M.

    2016-08-01

    Human pressures on the environment are changing spatially and temporally, with profound implications for the planet's biodiversity and human economies. Here we use recently available data on infrastructure, land cover and human access into natural areas to construct a globally standardized measure of the cumulative human footprint on the terrestrial environment at 1 km2 resolution from 1993 to 2009. We note that while the human population has increased by 23% and the world economy has grown 153%, the human footprint has increased by just 9%. Still, 75% the planet's land surface is experiencing measurable human pressures. Moreover, pressures are perversely intense, widespread and rapidly intensifying in places with high biodiversity. Encouragingly, we discover decreases in environmental pressures in the wealthiest countries and those with strong control of corruption. Clearly the human footprint on Earth is changing, yet there are still opportunities for conservation gains.

  19. Sixteen years of change in the global terrestrial human footprint and implications for biodiversity conservation

    PubMed Central

    Venter, Oscar; Sanderson, Eric W.; Magrach, Ainhoa; Allan, James R.; Beher, Jutta; Jones, Kendall R.; Possingham, Hugh P.; Laurance, William F.; Wood, Peter; Fekete, Balázs M.; Levy, Marc A.; Watson, James E. M.

    2016-01-01

    Human pressures on the environment are changing spatially and temporally, with profound implications for the planet's biodiversity and human economies. Here we use recently available data on infrastructure, land cover and human access into natural areas to construct a globally standardized measure of the cumulative human footprint on the terrestrial environment at 1 km2 resolution from 1993 to 2009. We note that while the human population has increased by 23% and the world economy has grown 153%, the human footprint has increased by just 9%. Still, 75% the planet's land surface is experiencing measurable human pressures. Moreover, pressures are perversely intense, widespread and rapidly intensifying in places with high biodiversity. Encouragingly, we discover decreases in environmental pressures in the wealthiest countries and those with strong control of corruption. Clearly the human footprint on Earth is changing, yet there are still opportunities for conservation gains. PMID:27552116

  20. Human influences on trophic cascades along rocky shores

    USGS Publications Warehouse

    Lindberg, D.R.; Estes, J.A.; Warheit, K.I.

    1998-01-01

    A three-trophic-level interaction among American Black Oystercatchers (Haematopus bachmani), limpets (Lottia spp.), and erect fleshy algae in rocky intertidal communities of central and southern California was documented via manipulative and 'natural' experiments. Removal of the territorial limpet (Lottia gigantea) initially caused large increases in the percent cover of erect fleshy algae, followed by a more gradual increase in density of small limpets (Lottia spp.) and a decline in algal cover. Algal cover increased following the removal of small limpets at the sites from which L. gigantea had been removed earlier, thus demonstrating that the large and small limpets had similar inhibitory effects on plant populations. A comparison of sites with and without oyster-catchers showed that L. gigantea occupied substrate inclinations in proportion to their availability at sites where oystercatchers were rare, whereas the distribution of L. gigantea was skewed toward vertically inclined substrates where oystercatchers were common. Survival rates of limpets translocated to horizontal and vertical substrates were similar in sites lacking oystercatcher predation, but were much lower on horizontal substrates where oystercatchers were common. Our results are consistent with those from several prior studies in demonstrating that shorelines frequented by humans typically lack oystercatchers. Humans also exploit L. gigantea and reduce populations to low densities of small individuals. These findings may explain why the midlittoral zone of rocky intertidal communities in western North America are so often dominated by high population densities of small limpets.

  1. Informing conservation management about structural versus functional connectivity: a case-study of Cross River gorillas.

    PubMed

    Imong, Inaoyom; Robbins, Martha M; Mundry, Roger; Bergl, Richard; Kühl, Hjalmar S

    2014-10-01

    Connectivity among subpopulations is vital for the persistence of small and fragmented populations. For management interventions to be effective conservation planners have to make the critical distinction between structural connectivity (based on landscape structure) and functional connectivity (which considers both landscape structure and organism-specific behavioral attributes) which can differ considerably within a given context. We assessed spatial and temporal changes in structural and functional connectivity of the Cross River gorilla Gorilla gorilla diehli (CRG) population in a 12,000 km(2) landscape in the Nigeria-Cameroon border region over a 23-year period, comparing two periods: 1987-2000 and 2000-2010. Despite substantial forest connections between occupied areas, genetic evidence shows that only limited dispersal occurs among CRG subpopulations. We used remotely sensed land-cover data and simulated human pressure (using a spatially explicit agent-based model) to assess human impact on connectivity of the CRG population. We calculated cost-weighted distances between areas occupied by gorillas as measures of connectivity (structural based on land-cover only, functional based on both land-cover and simulated human pressure). Whereas structural connectivity decreased by 5% over the 23-year period, functional connectivity decreased by 11%, with both decreasing more during the latter compared to the earlier period. Our results highlight the increasing threat of isolation of CRG subpopulations due to human disturbance, and provide insight into how increasing human influence may lead to functional isolation of wildlife populations despite habitat continuity, a pressing and common issue in tropical Africa often not accounted for when deciding management interventions. In addition to quantifying threats to connectivity, our study provides crucial evidence for management authorities to identify actions that are more likely to be effective for conservation of species in human-dominated landscapes. Our approach can be easily applied to other species, regions, and scales. © 2014 Wiley Periodicals, Inc.

  2. Re-creating missing population baselines for Pacific reef sharks.

    PubMed

    Nadon, Marc O; Baum, Julia K; Williams, Ivor D; McPherson, Jana M; Zgliczynski, Brian J; Richards, Benjamin L; Schroeder, Robert E; Brainard, Russell E

    2012-06-01

    Sharks and other large predators are scarce on most coral reefs, but studies of their historical ecology provide qualitative evidence that predators were once numerous in these ecosystems. Quantifying density of sharks in the absence of humans (baseline) is, however, hindered by a paucity of pertinent time-series data. Recently researchers have used underwater visual surveys, primarily of limited spatial extent or nonstandard design, to infer negative associations between reef shark abundance and human populations. We analyzed data from 1607 towed-diver surveys (>1 ha transects surveyed by observers towed behind a boat) conducted at 46 reefs in the central-western Pacific Ocean, reefs that included some of the world's most pristine coral reefs. Estimates of shark density from towed-diver surveys were substantially lower (<10%) than published estimates from surveys along small transects (<0.02 ha), which is not consistent with inverted biomass pyramids (predator biomass greater than prey biomass) reported by other researchers for pristine reefs. We examined the relation between the density of reef sharks observed in towed-diver surveys and human population in models that accounted for the influence of oceanic primary productivity, sea surface temperature, reef area, and reef physical complexity. We used these models to estimate the density of sharks in the absence of humans. Densities of gray reef sharks (Carcharhinus amblyrhynchos), whitetip reef sharks (Triaenodon obesus), and the group "all reef sharks" increased substantially as human population decreased and as primary productivity and minimum sea surface temperature (or reef area, which was highly correlated with temperature) increased. Simulated baseline densities of reef sharks under the absence of humans were 1.1-2.4/ha for the main Hawaiian Islands, 1.2-2.4/ha for inhabited islands of American Samoa, and 0.9-2.1/ha for inhabited islands in the Mariana Archipelago, which suggests that density of reef sharks has declined to 3-10% of baseline levels in these areas. ©2012 Society for Conservation Biology No claim to original US government works.

  3. Projected effects of climate and development on California wildfire emissions through 2100.

    PubMed

    Hurteau, Matthew D; Westerling, Anthony L; Wiedinmyer, Christine; Bryant, Benjamin P

    2014-02-18

    Changing climatic conditions are influencing large wildfire frequency, a globally widespread disturbance that affects both human and natural systems. Understanding how climate change, population growth, and development patterns will affect the area burned by and emissions from wildfires and how populations will in turn be exposed to emissions is critical for climate change adaptation and mitigation planning. We quantified the effects of a range of population growth and development patterns in California on emission projections from large wildfires under six future climate scenarios. Here we show that end-of-century wildfire emissions are projected to increase by 19-101% (median increase 56%) above the baseline period (1961-1990) in California for a medium-high temperature scenario, with the largest emissions increases concentrated in northern California. In contrast to other measures of wildfire impacts previously studied (e.g., structural loss), projected population growth and development patterns are unlikely to substantially influence the amount of projected statewide wildfire emissions. However, increases in wildfire emissions due to climate change may have detrimental impacts on air quality and, combined with a growing population, may result in increased population exposure to unhealthy air pollutants.

  4. Gray Wolf Exposure to Emerging Vector-Borne Diseases in Wisconsin with Comparison to Domestic Dogs and Humans.

    PubMed

    Jara, Rocio F; Wydeven, Adrian P; Samuel, Michael D

    2016-01-01

    World-wide concern over emerging vector-borne diseases has increased in recent years for both animal and human health. In the United Sates, concern about vector-borne diseases in canines has focused on Lyme disease, anaplasmosis, ehrlichiosis, and heartworm which infect domestic and wild canids. Of these diseases, Lyme and anaplasmosis are also frequently diagnosed in humans. Gray wolves (Canis lupus) recolonized Wisconsin in the 1970s, and we evaluated their temporal and geographic patterns of exposure to these four vector-borne diseases in Wisconsin as the population expanded between 1985 and 2011. A high proportion of the Wisconsin wolves were exposed to the agents that cause Lyme (65.6%) and anaplasma (47.7%), and a smaller proportion to ehrlichiosis (5.7%) and infected with heartworm (9.2%). Wolf exposure to tick borne diseases was consistently higher in older animals. Wolf exposure was markedly higher than domestic dog (Canis familiaris) exposure for all 4 disease agents during 2001-2013. We found a cluster of wolf exposure to Borrelia burgdorferi in northwestern Wisconsin, which overlaps human and domestic dog clusters for the same pathogen. In addition, wolf exposure to Lyme disease in Wisconsin has increased, corresponding with the increasing human incidence of Lyme disease in a similar time period. Despite generally high prevalence of exposure none of these diseases appear to have slowed the growth of the Wisconsin wolf population.

  5. Gray wolf exposure to emerging vector-borne diseases in Wisconsin with comparison to domestic dogs and humans

    USGS Publications Warehouse

    Jara, Rocio F.; Wydeven, Adrian P.; Samuel, Michael D.

    2016-01-01

    World-wide concern over emerging vector-borne diseases has increased in recent years for both animal and human health. In the United Sates, concern about vector-borne diseases in canines has focused on Lyme disease, anaplasmosis, ehrlichiosis, and heartworm which infect domestic and wild canids. Of these diseases, Lyme and anaplasmosis are also frequently diagnosed in humans. Gray wolves (Canis lupus) recolonized Wisconsin in the 1970s, and we evaluated their temporal and geographic patterns of exposure to these four vector-borne diseases in Wisconsin as the population expanded between 1985 and 2011. A high proportion of the Wisconsin wolves were exposed to the agents that cause Lyme (65.6%) and anaplasma (47.7%), and a smaller proportion to ehrlichiosis (5.7%) and infected with heartworm (9.2%). Wolf exposure to tick borne diseases was consistently higher in older animals. Wolf exposure was markedly higher than domestic dog (Canis familiaris) exposure for all 4 disease agents during 2001–2013. We found a cluster of wolf exposure to Borrelia burgdorferi in northwestern Wisconsin, which overlaps human and domestic dog clusters for the same pathogen. In addition, wolf exposure to Lyme disease in Wisconsin has increased, corresponding with the increasing human incidence of Lyme disease in a similar time period. Despite generally high prevalence of exposure none of these diseases appear to have slowed the growth of the Wisconsin wolf population.

  6. Human population growth and temperature increase along with the increase in urbanisation, motor vehicle numbers and green area amount in the sample of Erzurum city, Turkey.

    PubMed

    Yilmaz, Sevgi; Toy, Süleyman; Demircioglu Yildiz, Nalan; Yilmaz, Hasan

    2009-01-01

    In the study, main purpose was to determine the effect of population growth along with the increase in urbanisation, motor vehicle use and green area amount on the temperature values using a 55-year data set in Erzurum, which is hardly industrialised, and one of the coldest cities with highest elevation in Turkey. Although the semi-decadal increases, means of which are 0.1 degrees C for mean, minimum and maximum temperatures, are not clear enough to make a strong comment even in the lights of figures or tables, it was found as the result of the statistical analysis that population growth and increases in the number of vehicles, the number of buildings and the green area amount in the city have no significant effect on mean temperatures. However, the relationships between population growth and maximum temperature; and the number of vehicles and minimum temperature were found to be statistically significant.

  7. Age and sex bias in the reconstruction of past population structures.

    PubMed

    Bello, Silvia M; Thomann, Aminte; Signoli, Michel; Dutour, Olivier; Andrews, Peter

    2006-01-01

    Palaeodemographical studies are founded on the assumption that the sex and age distribution of the skeletal sample reflects the constitution of the original population. It is becoming increasingly clear, however, that the type and amount of information that may be derived from osteoarchaeological collections are related to the state of preservation of remains. This work proposes a new method to evaluate bone preservation, to identify age and sex biases in the preservation of human skeletal remains, and to assess whether differences in preservation patterns are more dependent on factors intrinsic or extrinsic to anatomical features of human bones. Three osteological collections and over 600 skeletons were observed. The state of preservation of human bones was assessed using three preservation indexes: the anatomical preservation index (API), the bone representation index (BRI), and the qualitative bone index (QBI). The results suggest that subadult skeletons are generally more poorly preserved and with bones less well-represented than adult skeletons. Among subadults, female and male skeletons have different patterns of preservation according to their age. This pattern of preservation depends on intrinsic anatomical properties of bones themselves, while external factors can only increase these differences in the state of preservation and representation of osseous remains. It is concluded from this that failure to recognize these differences may lead to misleading interpretations of paleodemography of past human populations.

  8. We have AN Increasing Need to Model Ourselves

    NASA Astrophysics Data System (ADS)

    Farmer, J. Doyne

    Pierre Teilhard de Chardin referred to the fusion of biological life, human culture, and technology as the noosphere. Technological improvement is causing the noosphere to evolve rapidly, driving the enormous increase in human population over the last 10,000 years and the transformation (and devastation) of the biosphere. The rapid proliferation of the internet is changing human culture, including everything from the way we find mates to the way democracy functions, or fails to function. The emergence of the BINC (Bio, Info, Nano, Cogno) technologies promises to further accelerate this change. We are acquiring an ever-increasing ability to engineer devices at a molecular level, to control the genome, and to create new forms of life and intelligence...

  9. Human activities cause distinct dissolved organic matter composition across freshwater ecosystems.

    PubMed

    Williams, Clayton J; Frost, Paul C; Morales-Williams, Ana M; Larson, James H; Richardson, William B; Chiandet, Aisha S; Xenopoulos, Marguerite A

    2016-02-01

    Dissolved organic matter (DOM) composition in freshwater ecosystems is influenced by the interactions among physical, chemical, and biological processes that are controlled, at one level, by watershed landscape, hydrology, and their connections. Against this environmental template, humans may strongly influence DOM composition. Yet, we lack a comprehensive understanding of DOM composition variation across freshwater ecosystems differentially affected by human activity. Using optical properties, we described DOM variation across five ecosystem groups of the Laurentian Great Lakes region: large lakes, Kawartha Lakes, Experimental Lakes Area, urban stormwater ponds, and rivers (n = 184 sites). We determined how between ecosystem variation in DOM composition related to watershed size, land use and cover, water quality measures (conductivity, dissolved organic carbon (DOC), nutrient concentration, chlorophyll a), and human population density. The five freshwater ecosystem groups had distinctive DOM composition from each other. These significant differences were not explained completely through differences in watershed size nor spatial autocorrelation. Instead, multivariate partial least squares regression showed that DOM composition was related to differences in human impact across freshwater ecosystems. In particular, urban/developed watersheds with higher human population densities had a unique DOM composition with a clear anthropogenic influence that was distinct from DOM composition in natural land cover and/or agricultural watersheds. This nonagricultural, human developed impact on aquatic DOM was most evident through increased levels of a microbial, humic-like parallel factor analysis component (C6). Lotic and lentic ecosystems with low human population densities had DOM compositions more typical of clear water to humic-rich freshwater ecosystems but C6 was only present at trace to background levels. Consequently, humans are strongly altering the quality of DOM in waters nearby or flowing through highly populated areas, which may alter carbon cycles in anthropogenically disturbed ecosystems at broad scales. © 2015 John Wiley & Sons Ltd.

  10. Human activities cause distinct dissolved organic matter composition across freshwater ecosystems

    USGS Publications Warehouse

    Williams, Clayton J.; Frost, Paul C.; Morales-Williams, Ana M.; Larson, James H.; Richardson, William B.; Chiandet, Aisha S.; Xenopoulos, Marguerite A.

    2016-01-01

    Dissolved organic matter (DOM) composition in freshwater ecosystems is influenced by interactions between physical, chemical, and biological processes that are controlled, at one level, by watershed landscape, hydrology, and their connections. Against this environmental template, humans may strongly influence DOM composition. Yet, we lack a comprehensive understanding of DOM composition variation across freshwater ecosystems differentially affected by human activity. Using optical properties, we described DOM variation across five ecosystem groups of the Laurentian Great Lakes Region: large lakes, Kawartha Lakes, Experimental Lakes Area, urban stormwater ponds, and rivers (n = 184 sites). We determined how between ecosystem variation in DOM composition related to watershed size, land use and cover, water quality measures (conductivity, dissolved organic carbon (DOC), nutrient concentration, chlorophyll a), and human population density. The five freshwater ecosystem groups had distinctive DOM composition from each other. These significant differences were not explained completely through differences in watershed size nor spatial autocorrelation. Instead, multivariate partial least squares regression showed that DOM composition was related to differences in human impact across freshwater ecosystems. In particular, urban/developed watersheds with higher human population densities had a unique DOM composition with a clear anthropogenic influence that was distinct from DOM composition in natural land cover and/or agricultural watersheds. This nonagricultural, human developed impact on aquatic DOM was most evident through increased levels of a microbial, humic-like parallel factor analysis component (C6). Lotic and lentic ecosystems with low human population densities had DOM compositions more typical of clear water to humic-rich freshwater ecosystems but C6 was only present at trace to background levels. Consequently, humans are strongly altering the quality of DOM in waters nearby or flowing through highly populated areas, which may alter carbon cycles in anthropogenically disturbed ecosystems at broad scales.

  11. A pragmatic trial to improve adherence with scheduled appointments in an inner-city pain clinic by human phone calls in the patient's preferred language.

    PubMed

    Andreae, Michael H; Nair, Singh; Gabry, Jonah S; Goodrich, Ben; Hall, Charles; Shaparin, Naum

    2017-11-01

    We investigated if human reminder phone calls in the patient's preferred language increase adherence with scheduled appointments in an inner-city chronic pain clinic. We hypothesized that language and cultural incongruence is the underlying mechanism to explain poor attendance at clinic appointments in underserved Hispanic populations. Pragmatic randomized controlled clinical trial SETTING: Innercity academic chronic pain clinic with a diverse, predominantly African-American and Hispanic population PATIENTS: All (n=963) adult patients with a scheduled first appointment between October 2014 and October 2015 at the Montefiore Pain Center in the Bronx, New York were enrolled. Patients were randomized to receive a human reminder call in their preferred language before their appointment, or no contact. We recorded patients' demographic characteristics and as primary outcome attendance as scheduled, failure to attend and/or cancellation calls. We fit Bayesian and classical multinomial logistic regression models to test if the intervention improved adherence with scheduled appointments. Among the 953 predominantly African American and Hispanic/Latino patients, 475 patients were randomly selected to receive a language-congruent, human reminder call, while 478 were assigned to receive no prior contact, (after we excluded 10 patients, scheduled for repeat appointments). In the experimental group, 275 patients adhered to their scheduled appointment, while 84 cancelled and 116 failed to attend. In the control group, 249 patients adhered to their scheduled appointment, 31 cancelled and 198 failed to attend. Human phone reminders in the preferred language increased adherence (RR 1.89, CI95% [1.42, 1.42], (p<0.01). The intervention seemed particularly effective in Hispanic patients, supporting our hypothesis of cultural congruence as possible underlying mechanism. Human reminder phone calls prior in the patient's preferred language increased adherence with scheduled appointments. The intervention facilitated access to much needed care in an ethnically diverse, resource poor population, presumably by overcoming language barriers. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Managing Southern Forests for Wildlife and Fish A Proceedings

    Treesearch

    James G. Dickson; O. Eugene Maughan; [Editors

    1987-01-01

    Southern forests are very productive for wildlife as well as wood fiber. User recreation demands for game and nongame wildlife and fish continue to increase as human populations grow in the sunbelt. The main determinant of wildlife populations is suitability of forest habitat and the primary manipulator of the habitat is the forester. Forestry decisions and...

  13. Genetic and environmental influences on adult human height across birth cohorts from 1886 to 1994.

    PubMed

    Jelenkovic, Aline; Hur, Yoon-Mi; Sund, Reijo; Yokoyama, Yoshie; Siribaddana, Sisira H; Hotopf, Matthew; Sumathipala, Athula; Rijsdijk, Fruhling; Tan, Qihua; Zhang, Dongfeng; Pang, Zengchang; Aaltonen, Sari; Heikkilä, Kauko; Öncel, Sevgi Y; Aliev, Fazil; Rebato, Esther; Tarnoki, Adam D; Tarnoki, David L; Christensen, Kaare; Skytthe, Axel; Kyvik, Kirsten O; Silberg, Judy L; Eaves, Lindon J; Maes, Hermine H; Cutler, Tessa L; Hopper, John L; Ordoñana, Juan R; Sánchez-Romera, Juan F; Colodro-Conde, Lucia; Cozen, Wendy; Hwang, Amie E; Mack, Thomas M; Sung, Joohon; Song, Yun-Mi; Yang, Sarah; Lee, Kayoung; Franz, Carol E; Kremen, William S; Lyons, Michael J; Busjahn, Andreas; Nelson, Tracy L; Whitfield, Keith E; Kandler, Christian; Jang, Kerry L; Gatz, Margaret; Butler, David A; Stazi, Maria A; Fagnani, Corrado; D'Ippolito, Cristina; Duncan, Glen E; Buchwald, Dedra; Derom, Catherine A; Vlietinck, Robert F; Loos, Ruth Jf; Martin, Nicholas G; Medland, Sarah E; Montgomery, Grant W; Jeong, Hoe-Uk; Swan, Gary E; Krasnow, Ruth; Magnusson, Patrik Ke; Pedersen, Nancy L; Dahl-Aslan, Anna K; McAdams, Tom A; Eley, Thalia C; Gregory, Alice M; Tynelius, Per; Baker, Laura A; Tuvblad, Catherine; Bayasgalan, Gombojav; Narandalai, Danshiitsoodol; Lichtenstein, Paul; Spector, Timothy D; Mangino, Massimo; Lachance, Genevieve; Bartels, Meike; van Beijsterveldt, Toos Cem; Willemsen, Gonneke; Burt, S Alexandra; Klump, Kelly L; Harris, Jennifer R; Brandt, Ingunn; Nilsen, Thomas Sevenius; Krueger, Robert F; McGue, Matt; Pahlen, Shandell; Corley, Robin P; Hjelmborg, Jacob V B; Goldberg, Jack H; Iwatani, Yoshinori; Watanabe, Mikio; Honda, Chika; Inui, Fujio; Rasmussen, Finn; Huibregtse, Brooke M; Boomsma, Dorret I; Sørensen, Thorkild I A; Kaprio, Jaakko; Silventoinen, Karri

    2016-12-14

    Human height variation is determined by genetic and environmental factors, but it remains unclear whether their influences differ across birth-year cohorts. We conducted an individual-based pooled analysis of 40 twin cohorts including 143,390 complete twin pairs born 1886-1994. Although genetic variance showed a generally increasing trend across the birth-year cohorts, heritability estimates (0.69-0.84 in men and 0.53-0.78 in women) did not present any clear pattern of secular changes. Comparing geographic-cultural regions (Europe, North America and Australia, and East Asia), total height variance was greatest in North America and Australia and lowest in East Asia, but no clear pattern in the heritability estimates across the birth-year cohorts emerged. Our findings do not support the hypothesis that heritability of height is lower in populations with low living standards than in affluent populations, nor that heritability of height will increase within a population as living standards improve.

  14. Kin groups and trait groups: population structure and epidemic disease selection.

    PubMed

    Fix, A G

    1984-10-01

    A Monte Carlo simulation based on the population structure of a small-scale human population, the Semai Senoi of Malaysia, has been developed to study the combined effects of group, kin, and individual selection. The population structure resembles D.S. Wilson's structured deme model in that local breeding populations (Semai settlements) are subdivided into trait groups (hamlets) that may be kin-structured and are not themselves demes. Additionally, settlement breeding populations are connected by two-dimensional stepping-stone migration approaching 30% per generation. Group and kin-structured group selection occur among hamlets the survivors of which then disperse to breed within the settlement population. Genetic drift is modeled by the process of hamlet formation; individual selection as a deterministic process, and stepping-stone migration as either random or kin-structured migrant groups. The mechanism for group selection is epidemics of infectious disease that can wipe out small hamlets particularly if most adults become sick and social life collapses. Genetic resistance to a disease is an individual attribute; however, hamlet groups with several resistant adults are less likely to disintegrate and experience high social mortality. A specific human gene, hemoglobin E, which confers resistance to malaria, is studied as an example of the process. The results of the simulations show that high genetic variance among hamlet groups may be generated by moderate degrees of kin-structuring. This strong microdifferentiation provides the potential for group selection. The effect of group selection in this case is rapid increase in gene frequencies among the total set of populations. In fact, group selection in concert with individual selection produced a faster rate of gene frequency increase among a set of 25 populations than the rate within a single unstructured population subject to deterministic individual selection. Such rapid evolution with plausible rates of extinction, individual selection, and migration and a population structure realistic in its general form, has implications for specific human polymorphisms such as hemoglobin variants and for the more general problem of the tempo of evolution as well.

  15. Maintenance and construction operations user service : an addendum to the ITS program plan

    DOT National Transportation Integrated Search

    1997-09-01

    Technological advances, changing roles of men and women in society, increases in the elderly population, and our increased knowledge of human behavior have significantly impacted our lives in the last quarter of the 20th century. Our travel behavior ...

  16. Urban life of Galapagos sea lions (Zalophus wollebaeki) on San Cristobal Island, Ecuador: colony trends and threats

    NASA Astrophysics Data System (ADS)

    Denkinger, Judith; Gordillo, Luis; Montero-Serra, Ignasi; Murillo, Juan Carlos; Guevara, Nataly; Hirschfeld, Maximilian; Fietz, Katharina; Rubianes, Francisco; Dan, Michael

    2015-11-01

    Worldwide, pristine environments are influenced by human societies. In the Galapagos Islands, the endangered, endemic Galapagos sea lion (Zalophus wollebaeki) has formed one of the biggest colonies within the town center of Puerto Baquerizo Moreno. About 8,000 people live there and human wildlife interactions occur daily. With colony counts and direct observations from 2008 to 2012, we analyze cause of death, injuries and disease of urban sea lion colonies at Wreck Bay. Population increase since 2008 can be attributed to an immigration of adult sea lions in 2010, resulting in an increase in the pup and juvenile production in 2011 and 2012. Pup mortality increased drastically to 2009 and again in 2011 and 2012. Besides pup mortality, most of the deaths are caused by increased disease incidences and human activity. Our observations suggest that overall 65% of the injuries observed are produced by human interaction. The increase in threats leading to death, injuries or disease can have long-term effects on the population. Although threats that cause physical injuries can be managed locally, sea lions range movements contributes to the spread of infectious pathogens, which may affect neighbor colonies and potentially have an impact on the survival of the species. Our study reveals the need of stronger efforts towards a more complete understanding of threats and especially disease spread among Galapagos Sea lions in urban environments and the establishment of more effective management measures.

  17. Estimating the contribution of genetic variants to difference in incidence of disease between population groups.

    PubMed

    Moonesinghe, Ramal; Ioannidis, John P A; Flanders, W Dana; Yang, Quanhe; Truman, Benedict I; Khoury, Muin J

    2012-08-01

    Genome-wide association studies have identified multiple genetic susceptibility variants to several complex human diseases. However, risk-genotype frequency at loci showing robust associations might differ substantially among different populations. In this paper, we present methods to assess the contribution of genetic variants to the difference in the incidence of disease between different population groups for different scenarios. We derive expressions for the contribution of a single genetic variant, multiple genetic variants, and the contribution of the joint effect of a genetic variant and an environmental factor to the difference in the incidence of disease. The contribution of genetic variants to the difference in incidence increases with increasing difference in risk-genotype frequency, but declines with increasing difference in incidence between the two populations. The contribution of genetic variants also increases with increasing relative risk and the contribution of joint effect of genetic and environmental factors increases with increasing relative risk of the gene-environmental interaction. The contribution of genetic variants to the difference in incidence between two populations can be expressed as a function of the population attributable risks of the genetic variants in the two populations. The contribution of a group of genetic variants to the disparity in incidence of disease could change considerably by adding one more genetic variant to the group. Any estimate of genetic contribution to the disparity in incidence of disease between two populations at this stage seems to be an elusive goal.

  18. Estimating the contribution of genetic variants to difference in incidence of disease between population groups

    PubMed Central

    Moonesinghe, Ramal; Ioannidis, John PA; Flanders, W Dana; Yang, Quanhe; Truman, Benedict I; Khoury, Muin J

    2012-01-01

    Genome-wide association studies have identified multiple genetic susceptibility variants to several complex human diseases. However, risk-genotype frequency at loci showing robust associations might differ substantially among different populations. In this paper, we present methods to assess the contribution of genetic variants to the difference in the incidence of disease between different population groups for different scenarios. We derive expressions for the contribution of a single genetic variant, multiple genetic variants, and the contribution of the joint effect of a genetic variant and an environmental factor to the difference in the incidence of disease. The contribution of genetic variants to the difference in incidence increases with increasing difference in risk-genotype frequency, but declines with increasing difference in incidence between the two populations. The contribution of genetic variants also increases with increasing relative risk and the contribution of joint effect of genetic and environmental factors increases with increasing relative risk of the gene–environmental interaction. The contribution of genetic variants to the difference in incidence between two populations can be expressed as a function of the population attributable risks of the genetic variants in the two populations. The contribution of a group of genetic variants to the disparity in incidence of disease could change considerably by adding one more genetic variant to the group. Any estimate of genetic contribution to the disparity in incidence of disease between two populations at this stage seems to be an elusive goal. PMID:22333905

  19. Population remains top priority for China.

    PubMed

    Li, H

    1998-04-01

    China, whose population was 430 million in 1840, is facing a population total of 1.3 billion in 2000. Population increased rapidly in the country during the 1950s, but early efforts at population control were abandoned from the start of the Cultural Revolution in 1966 until the 1970s. Today, the importance of family planning (FP) is recognized throughout Chinese society. With 20 million newborns adding 13 million people to the population each year, controlling the population increase will remain a top priority of China's population policy. Other priorities include 1) increasing the quality of life of the population by improving health, promoting literacy, and developing human resources; 2) facing the impact of population aging; 3) struggling to overcome the poverty experienced by 50 million people; and 4) dealing with the imbalanced sex ratio of newborns. China has been attempting to institute strategies to implement the Program of Action adopted by the 1994 International Conference on Population and Development and is attempting to adopt an integrated approach to population programs that combines FP with development measures and the delivery of multiple services to enhance reproductive health. Since 1984, China has worked with Japan's JOICFP on an Integrated Project that offers FP, maternal and child health services, and parasite control.

  20. Nest suitability, fine-scale population structure and male-mediated dispersal of a solitary ground nesting bee in an urban landscape.

    PubMed

    López-Uribe, Margarita M; Morreale, Stephen J; Santiago, Christine K; Danforth, Bryan N

    2015-01-01

    Bees are the primary pollinators of flowering plants in almost all ecosystems. Worldwide declines in bee populations have raised awareness about the importance of their ecological role in maintaining ecosystem functioning. The naturally strong philopatric behavior that some bee species show can be detrimental to population viability through increased probability of inbreeding. Furthermore, bee populations found in human-altered landscapes, such as urban areas, can experience lower levels of gene flow and effective population sizes, increasing potential for inbreeding depression in wild bee populations. In this study, we investigated the fine-scale population structure of the solitary bee Colletes inaequalis in an urbanized landscape. First, we developed a predictive spatial model to detect suitable nesting habitat for this ground nesting bee and to inform our field search for nests. We genotyped 18 microsatellites in 548 female individuals collected from nest aggregations throughout the study area. Genetic relatedness estimates revealed that genetic similarity among individuals was slightly greater within nest aggregations than among randomly chosen individuals. However, genetic structure among nest aggregations was low (Nei's GST = 0.011). Reconstruction of parental genotypes revealed greater genetic relatedness among females than among males within nest aggregations, suggesting male-mediated dispersal as a potentially important mechanism of population connectivity and inbreeding avoidance. Size of nesting patch was positively correlated with effective population size, but not with other estimators of genetic diversity. We detected a positive trend between geographic distance and genetic differentiation between nest aggregations. Our landscape genetic models suggest that increased urbanization is likely associated with higher levels of inbreeding. Overall, these findings emphasize the importance of density and distribution of suitable nesting patches for enhancing bee population abundance and connectivity in human dominated habitats and highlights the critical contribution of landscape genetic studies for enhanced conservation and management of native pollinators.

  1. Nest Suitability, Fine-Scale Population Structure and Male-Mediated Dispersal of a Solitary Ground Nesting Bee in an Urban Landscape

    PubMed Central

    López-Uribe, Margarita M.; Morreale, Stephen J.; Santiago, Christine K.; Danforth, Bryan N.

    2015-01-01

    Bees are the primary pollinators of flowering plants in almost all ecosystems. Worldwide declines in bee populations have raised awareness about the importance of their ecological role in maintaining ecosystem functioning. The naturally strong philopatric behavior that some bee species show can be detrimental to population viability through increased probability of inbreeding. Furthermore, bee populations found in human-altered landscapes, such as urban areas, can experience lower levels of gene flow and effective population sizes, increasing potential for inbreeding depression in wild bee populations. In this study, we investigated the fine-scale population structure of the solitary bee Colletes inaequalis in an urbanized landscape. First, we developed a predictive spatial model to detect suitable nesting habitat for this ground nesting bee and to inform our field search for nests. We genotyped 18 microsatellites in 548 female individuals collected from nest aggregations throughout the study area. Genetic relatedness estimates revealed that genetic similarity among individuals was slightly greater within nest aggregations than among randomly chosen individuals. However, genetic structure among nest aggregations was low (Nei’s GST = 0.011). Reconstruction of parental genotypes revealed greater genetic relatedness among females than among males within nest aggregations, suggesting male-mediated dispersal as a potentially important mechanism of population connectivity and inbreeding avoidance. Size of nesting patch was positively correlated with effective population size, but not with other estimators of genetic diversity. We detected a positive trend between geographic distance and genetic differentiation between nest aggregations. Our landscape genetic models suggest that increased urbanization is likely associated with higher levels of inbreeding. Overall, these findings emphasize the importance of density and distribution of suitable nesting patches for enhancing bee population abundance and connectivity in human dominated habitats and highlights the critical contribution of landscape genetic studies for enhanced conservation and management of native pollinators. PMID:25950429

  2. Population growth and consumption.

    PubMed

    Chalkley, K

    1997-04-01

    The relationship between population growth, resource consumption, and environmental degradation is complex. The rise in "greenhouse gases" that will cause climatic change is clearly due to human activity, and pollutants are often concentrated in densely populated areas. However, even an area with a negative population growth, such as Russia, can experience severe environmental degradation due to poor management. Consumption patterns have the most effect on ozone depletion, while population growth threatens biodiversity of and within species through the destruction of ecosystems. Migration joins population growth and social factors, such as land inequality, as major causes of deforestation, and global demand for water is expected to increase faster than the rate of population growth. Coastal development and over-fishing threaten to deplete the oceans, while soil quality is threatened by inappropriate land use. Estimates of the earth's carrying capacity range from less than 3 billion to more than 44 billion people, indicating how difficult it is to assess this figure. Development efforts throughout the world may lead to human gains that will ultimately be negated by environmental losses. These factors have led to growing support for environmentally sustainable development.

  3. Population density, water supply, and the risk of dengue fever in Vietnam: cohort study and spatial analysis.

    PubMed

    Schmidt, Wolf-Peter; Suzuki, Motoi; Thiem, Vu Dinh; White, Richard G; Tsuzuki, Ataru; Yoshida, Lay-Myint; Yanai, Hideki; Haque, Ubydul; Tho, Le Huu; Anh, Dang Duc; Ariyoshi, Koya

    2011-08-01

    Aedes aegypti, the major vector of dengue viruses, often breeds in water storage containers used by households without tap water supply, and occurs in high numbers even in dense urban areas. We analysed the interaction between human population density and lack of tap water as a cause of dengue fever outbreaks with the aim of identifying geographic areas at highest risk. We conducted an individual-level cohort study in a population of 75,000 geo-referenced households in Vietnam over the course of two epidemics, on the basis of dengue hospital admissions (n = 3,013). We applied space-time scan statistics and mathematical models to confirm the findings. We identified a surprisingly narrow range of critical human population densities between around 3,000 to 7,000 people/km² prone to dengue outbreaks. In the study area, this population density was typical of villages and some peri-urban areas. Scan statistics showed that areas with a high population density or adequate water supply did not experience severe outbreaks. The risk of dengue was higher in rural than in urban areas, largely explained by lack of piped water supply, and in human population densities more often falling within the critical range. Mathematical modeling suggests that simple assumptions regarding area-level vector/host ratios may explain the occurrence of outbreaks. Rural areas may contribute at least as much to the dissemination of dengue fever as cities. Improving water supply and vector control in areas with a human population density critical for dengue transmission could increase the efficiency of control efforts. Please see later in the article for the Editors' Summary.

  4. Population Density, Water Supply, and the Risk of Dengue Fever in Vietnam: Cohort Study and Spatial Analysis

    PubMed Central

    Schmidt, Wolf-Peter; Suzuki, Motoi; Dinh Thiem, Vu; White, Richard G.; Tsuzuki, Ataru; Yoshida, Lay-Myint; Yanai, Hideki; Haque, Ubydul; Huu Tho, Le; Anh, Dang Duc; Ariyoshi, Koya

    2011-01-01

    Background Aedes aegypti, the major vector of dengue viruses, often breeds in water storage containers used by households without tap water supply, and occurs in high numbers even in dense urban areas. We analysed the interaction between human population density and lack of tap water as a cause of dengue fever outbreaks with the aim of identifying geographic areas at highest risk. Methods and Findings We conducted an individual-level cohort study in a population of 75,000 geo-referenced households in Vietnam over the course of two epidemics, on the basis of dengue hospital admissions (n = 3,013). We applied space-time scan statistics and mathematical models to confirm the findings. We identified a surprisingly narrow range of critical human population densities between around 3,000 to 7,000 people/km2 prone to dengue outbreaks. In the study area, this population density was typical of villages and some peri-urban areas. Scan statistics showed that areas with a high population density or adequate water supply did not experience severe outbreaks. The risk of dengue was higher in rural than in urban areas, largely explained by lack of piped water supply, and in human population densities more often falling within the critical range. Mathematical modeling suggests that simple assumptions regarding area-level vector/host ratios may explain the occurrence of outbreaks. Conclusions Rural areas may contribute at least as much to the dissemination of dengue fever as cities. Improving water supply and vector control in areas with a human population density critical for dengue transmission could increase the efficiency of control efforts. Please see later in the article for the Editors' Summary PMID:21918642

  5. Human impacts on bear habitat use

    USGS Publications Warehouse

    Mattson, David J.

    1990-01-01

    : Human effects on bear habitat use are mediated through food biomass changes, bear tolerance of humans and their impacts, and human tolerance of bears. Large-scale changes in bear food biomass have been caused by conversion of wildlands and waterways to intensive human use, and by the introduction of exotic pathogens. Bears consume virtually all human foods that have been established in former wildlands, but bear use has been limited by access. Air pollution has also affected bear food biomass on a small scale and is likely to have major future impacts on bear habitat through climatic warming. Major changes in disturbance cycles and landscape mosaics wrought by humans have further altered temporal and spatial pulses of bear food production. These changes have brought short-term benefits in places, but have also added long-term stresses to most bear populations. Although bears tend to avoid humans, they will also use exotic and native foods in close proximity to humans. Subadult males and adult females are more often impelled to forage closer to humans because of their energetic predicament and because more secure sites are often preempted by adult males. Although male bears are typically responsible for most livestock predation, adult females and subadult males are more likely to be habituated to humans because they tend to forage closer to humans. Elimination of human-habituated bears predictably reduces effective carrying capacity and is more likely to be a factor in preserving bear populations where humans are present in moderate-to-high densities. If humans desire to preserve viable bear populations, they will either have to accept increased risk of injury associated with preserving habituated animals, or continue to crop habituated bears while at the same time preserving large tracts of wildlands free from significant human intrusion.

  6. Impacts of population growth, urbanisation and sanitation changes on global human Cryptosporidium emissions to surface water.

    PubMed

    Hofstra, Nynke; Vermeulen, Lucie C

    2016-10-01

    Cryptosporidium is a pathogenic protozoan parasite and is a leading cause of diarrhoea worldwide. The concentration of Cryptosporidium in the surface water is a determinant for probability of exposure and the risk of disease. Surface water concentrations are expected to change with population growth, urbanisation and changes in sanitation. The objective of this paper is to assess the importance of future changes in population, urbanisation and sanitation on global human emissions of Cryptosporidium to surface water. The GloWPa-Crypto H1 (the Global Waterborne Pathogen model for Human Cryptosporidium emissions version 1) model is presented and run for 2010 and with scenarios for 2050. The new scenarios are based on the Shared Socio-economic Pathways (SSPs) developed for the climate community. The scenarios comprise assumptions on sanitation changes in line with the storylines and population and urbanisation changes from the SSPs. In SSP1 population growth is limited, urbanisation large and sanitation and waste water treatment strongly improve. SSP1* is the same as SSP1, but waste water treatment does not improve. SSP3 sees large population growth, moderate urbanisation and sanitation and waste water treatment fractions that are the same as in 2010. Total global Cryptosporidium emissions to surface water for 2010 are estimated to be 1.6×10 17 oocysts per year, with hotspots in the most urbanised parts of the world. In 2050 emissions are expected to decrease by 24% or increase by 52% and 70% for SSP1, SSP3 and SSP1* respectively. The emissions increase in all scenarios for countries in the Middle East and Africa (MAF) region, while emissions in large parts in Europe decrease in scenarios SSP1 and SSP3. Improving sanitation by connecting the population to sewers, should be combined with waste water treatment, otherwise (SSP1*) emissions in 2050 are expected to be much larger than in a situation with strong population growth and slow development of safe water and improved sanitation (SSP3). The results show that population increase, urbanisation and changes in sanitation should be considered when water quality and resulting health risks are estimated by water managers or public health specialists. Copyright © 2016 Elsevier GmbH. All rights reserved.

  7. Adolescent leadership and adulthood fertility: revisiting the "central theoretical problem of human sociobiology".

    PubMed

    Jokela, Markus; Keltikangas-Järvinen, Liisa

    2009-02-01

    Human motivation for social status may reflect an evolved psychological adaptation that increased individual reproductive success in the evolutionary past. However, the association between status striving and reproduction in contemporary humans is unclear. It may be hypothesized that personality traits related to status achievement increase fertility even if modern indicators of socioeconomic status do not. We examined whether four subcomponents of type-A personality--leadership, hard-driving, eagerness, and aggressiveness--assessed at the age of 12 to 21 years predicted the likelihood of having children by the age of 39 in a population-based sample of Finnish women and men (N=1,313). Survival analyses indicated that high adolescent leadership increased adulthood fertility in men and women, independently of education level and urbanicity of residence. The findings suggest that personality determinants of status achievement may predict increased reproductive success in contemporary humans.

  8. The peopling of the African continent and the diaspora into the new world

    PubMed Central

    Campbell, Michael C; Hirbo, Jibril B; Townsend, Jeffrey P; Tishkoff, Sarah A

    2014-01-01

    Africa is the birthplace of anatomically modern humans, and is the geographic origin of human migration across the globe within the last 100,000 years. The history of African populations has consisted of a number of demographic events that have influenced patterns of genetic and phenotypic variation across the continent. With the increasing amount of genomic data and corresponding developments in computational methods, researchers are able to explore long-standing evolutionary questions, expanding our understanding of human history within and outside of Africa. This review will summarize some of the recent findings regarding African demographic history, including the African Diaspora, and will briefly explore their implications for disease susceptibility in populations of African descent. PMID:25461616

  9. Committee opinion no. 507: human trafficking.

    PubMed

    2011-09-01

    Human trafficking is a widespread problem with estimates ranging from 14,000 to 50,000 individuals trafficked into the United States annually. This hidden population involves the commercial sex industry, agriculture, factories, hotel and restaurant businesses, domestic workers, marriage brokers, and some adoption firms. Because 80% of trafficked individuals are women and girls, women’s health care providers may better serve their diverse patient population by increasing their awareness of this problem. The exploitation of people of any race, gender, sexual orientation, or ethnicity is unacceptable at any time, in any place. The members of the American College of Obstetricians and Gynecologists should be aware of this problem and strive to recognize and assist their patients who are victims or who have been victims of human trafficking.

  10. American Exceptionalism: Population Trends and Flight Initiation Distances in Birds from Three Continents

    PubMed Central

    Møller, Anders Pape; Samia, Diogo S. M.; Weston, Mike A.; Guay, Patrick-Jean; Blumstein, Daniel T.

    2014-01-01

    Background All organisms may be affected by humans' increasing impact on Earth, but there are many potential drivers of population trends and the relative importance of each remains largely unknown. The causes of spatial patterns in population trends and their relationship with animal responses to human proximity are even less known. Methodology/Principal Finding We investigated the relationship between population trends of 193 species of bird in North America, Australia and Europe and flight initiation distance (FID); the distance at which birds take flight when approached by a human. While there is an expected negative relationship between population trend and FID in Australia and Europe, we found the inverse relationship for North American birds; thus FID cannot be used as a universal predictor of vulnerability of birds. However, the analysis of the joint explanatory ability of multiple drivers (farmland breeding habitat, pole-most breeding latitude, migratory habit, FID) effects on population status replicated previously reported strong effects of farmland breeding habitat (an effect apparently driven mostly by European birds), as well as strong effects of FID, body size, migratory habit and continent. Farmland birds are generally declining. Conclusions/Significance Flight initiation distance is related to population trends in a way that differs among continents opening new research possibilities concerning the causes of geographic differences in patterns of anti-predator behavior. PMID:25226165

  11. HTLV-3/4 and simian foamy retroviruses in humans: discovery, epidemiology, cross-species transmission and molecular virology.

    PubMed

    Gessain, Antoine; Rua, Réjane; Betsem, Edouard; Turpin, Jocelyn; Mahieux, Renaud

    2013-01-05

    Non-human primates are considered to be likely sources of viruses that can infect humans and thus pose a significant threat to human population. This is well illustrated by some retroviruses, as the simian immunodeficiency viruses and the simian T lymphotropic viruses, which have the ability to cross-species, adapt to a new host and sometimes spread. This leads to a pandemic situation for HIV-1 or an endemic one for HTLV-1. Here, we present the available data on the discovery, epidemiology, cross-species transmission and molecular virology of the recently discovered HTLV-3 and HTLV-4 deltaretroviruses, as well as the simian foamy retroviruses present in different human populations at risk, especially in central African hunters. We discuss also the natural history in humans of these retroviruses of zoonotic origin (magnitude and geographical distribution, possible inter-human transmission). In Central Africa, the increase of the bushmeat trade during the last decades has opened new possibilities for retroviral emergence in humans, especially in immuno-compromised persons. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. The local lymph node assay compared with the human maximization test as an indicator of allergic potency in humans using patch test clinic populations.

    PubMed

    Zaghi, Danny; Maibach, Howard I

    2009-01-01

    The human maximization test (HMT) is a method to evaluate potency in humans, while the local lymph node assay (LLNA) is a test method that allows for the measuring of the allergic potency of a substance in a rodent. It has been proposed that an EC3 value (the value obtained by the LLNA test, ie, the concentration of an allergen leading to a 3-fold increase of baseline proliferation rate) would be a reliable indicator for a compound's allergic potency in humans. This paper compares the correlation between the EC3 value of a compound and its allergic occurrence in the general population with the correlation between the HMT of the compound and its allergic occurrence in the general population, to determine the relationship to potency. The correlation values when outliers were removed from the sample were -0.56 and -0.71 for LLNA and HMT, respectively, suggesting that there is a possible 20% error margin in LLNA's ability to predict potency. The data also suggest that other factors (such as exposure) could play up to a 30% role in the determination of allergic occurrence in the general population. The potency assays might be made more clinically relevant for predicting allergic frequencies by including a frequency factor and other factors in its dermatotoxicological interpretation.

  13. Consequences of non-intervention for infectious disease in African great apes.

    PubMed

    Ryan, Sadie J; Walsh, Peter D

    2011-01-01

    Infectious disease has recently joined poaching and habitat loss as a major threat to African apes. Both "naturally" occurring pathogens, such as Ebola and Simian Immunodeficiency Virus (SIV), and respiratory pathogens transmitted from humans, have been confirmed as important sources of mortality in wild gorillas and chimpanzees. While awareness of the threat has increased, interventions such as vaccination and treatment remain controversial. Here we explore both the risk of disease to African apes, and the status of potential responses. Through synthesis of published data, we summarize prior disease impact on African apes. We then use a simple demographic model to illustrate the resilience of a well-known gorilla population to disease, modeled on prior documented outbreaks. We found that the predicted recovery time for this specific gorilla population from a single outbreak ranged from 5 years for a low mortality (4%) respiratory outbreak, to 131 years for an Ebola outbreak that killed 96% of the population. This shows that mortality rates comparable to those recently reported for disease outbreaks in wild populations are not sustainable. This is particularly troubling given the rising pathogen risk created by increasing habituation of wild apes for tourism, and the growth of human populations surrounding protected areas. We assess potential future disease spillover risk in terms of vaccination rates amongst humans that may come into contact with wild apes, and the availability of vaccines against potentially threatening diseases. We discuss and evaluate non-interventionist responses such as limiting tourist access to apes, community health programs, and safety, logistic, and cost issues that constrain the potential of vaccination. © 2011 Ryan and Walsh.

  14. Consequences of Non-Intervention for Infectious Disease in African Great Apes

    PubMed Central

    Ryan, Sadie J.; Walsh, Peter D.

    2011-01-01

    Infectious disease has recently joined poaching and habitat loss as a major threat to African apes. Both “naturally” occurring pathogens, such as Ebola and Simian Immunodeficiency Virus (SIV), and respiratory pathogens transmitted from humans, have been confirmed as important sources of mortality in wild gorillas and chimpanzees. While awareness of the threat has increased, interventions such as vaccination and treatment remain controversial. Here we explore both the risk of disease to African apes, and the status of potential responses. Through synthesis of published data, we summarize prior disease impact on African apes. We then use a simple demographic model to illustrate the resilience of a well-known gorilla population to disease, modeled on prior documented outbreaks. We found that the predicted recovery time for this specific gorilla population from a single outbreak ranged from 5 years for a low mortality (4%) respiratory outbreak, to 131 years for an Ebola outbreak that killed 96% of the population. This shows that mortality rates comparable to those recently reported for disease outbreaks in wild populations are not sustainable. This is particularly troubling given the rising pathogen risk created by increasing habituation of wild apes for tourism, and the growth of human populations surrounding protected areas. We assess potential future disease spillover risk in terms of vaccination rates amongst humans that may come into contact with wild apes, and the availability of vaccines against potentially threatening diseases. We discuss and evaluate non-interventionist responses such as limiting tourist access to apes, community health programs, and safety, logistic, and cost issues that constrain the potential of vaccination. PMID:22216162

  15. Anthropogenic habitat disturbance and the dynamics of hantavirus using remote sensing, GIS, and a spatially explicit agent-based model

    NASA Astrophysics Data System (ADS)

    Cao, Lina

    Sin Nombre virus (SNV), a strain of hantavirus, causes hantavirus pulmonary syndrome (HPS) in humans, a deadly disease with high mortality rate (>50%). The primary virus host is deer mice, and greater deer mice abundance has been shown to increase the human risk of HPS. There is a great need in understanding the nature of the virus host, its temporal and spatial dynamics, and its relation to the human population with the purpose of predicting human risk of the disease. This research studies SNV dynamics in deer mice in the Great Basin Desert of central Utah, USA using multiyear field data and integrated geospatial approaches including remote sensing, Geographic Information System (GIS), and a spatially explicit agent-based model. The goal is to advance our understanding of the important ecological and demographic factors that affect the dynamics of deer mouse population and SNV prevalence. The primary research question is how climate, habitat disturbance, and deer mouse demographics affect deer mouse population density, its movement, and SNV prevalence in the sagebrush habitat. The results show that the normalized difference vegetation index (NDVI) and the enhanced vegetation index (EVI) can be good predictors of deer mouse density and the number of infected deer mice with a time lag of 1.0 to 1.3 years. This information can be very useful in predicting mouse abundance and SNV risk. The results also showed that climate, mouse density, sex, mass, and SNV infection had significant effects on deer mouse movement. The effect of habitat disturbance on mouse movement varies according to climate conditions with positive relationship in predrought condition and negative association in postdrought condition. The heavier infected deer mice moved the most. Season and disturbance alone had no significant effects. The spatial agent-based model (SABM) simulation results show that prevalence was negatively related to the disturbance levels and the sensitivity analysis showed that population density was one of the most important parameters affecting the SNV dynamics. The results also indicated that habitat disturbance could increase hantavirus transmission likely by increasing the movement and consequently contact rates. However, the model suggested that habitat disturbance had a much stronger effect on prevalence by decreasing population density than by increasing mice movement. Therefore, overall habitat disturbance reduces SNV prevalence.

  16. River Networks and Human Activities: Global Fractal Analysis Using Nightlight Data

    NASA Astrophysics Data System (ADS)

    McCurley, K. 4553; Fang, Y.; Ceola, S.; Paik, K.; McGrath, G. S.; Montanari, A.; Rao, P. S.; Jawitz, J. W.

    2016-12-01

    River networks hold an important historical role in affecting human population distribution. In this study, we link the geomorphological structure of river networks to the pattern of human activities at a global scale. We use nightlights as a valuable proxy for the presence of human settlements and economic activity, and we employ HydroSHEDS as the main data source on river networks. We test the hypotheses that, analogous to Horton's laws, human activities (magnitude of nightlights) also show scaling relationship with stream order, and that the intensity of human activities decrease as the distance from the basin outlet increase. Our results demonstrate that the distribution of human activities shows a fractal structure, with power-law scaling between human activities and stream order. This relationship is robust among global river basins. Human activities are more concentrated in larger order basins, but show large variation in equivalent order basins, with higher population density emergent in the basins connected with high-order rivers. For all global river basins longer than 400km, the average intensity of human activities decrease as the distance to the outlets increases, albeit with signatures of large cities at varied distances. The power spectrum of human width (area) function is found to exhibit power law scaling, with a scaling exponent that indicates enrichment of low frequency variation. The universal fractal structure of human activities may reflect an optimum arrangement for humans in river basins to better utilize the water resources, ecological assets, and geographic advantages. The generalized patterns of human activities could be applied to better understand hydrologic and biogeochemical responses in river basins, and to advance catchment management.

  17. Role of India's wildlife in the emergence and re-emergence of zoonotic pathogens, risk factors and public health implications.

    PubMed

    Singh, B B; Gajadhar, A A

    2014-10-01

    Evolving land use practices have led to an increase in interactions at the human/wildlife interface. The presence and poor knowledge of zoonotic pathogens in India's wildlife and the occurrence of enormous human populations interfacing with, and critically linked to, forest ecosystems warrant attention. Factors such as diverse migratory bird populations, climate change, expanding human population and shrinking wildlife habitats play a significant role in the emergence and re-emergence of zoonotic pathogens from India's wildlife. The introduction of a novel Kyasanur forest disease virus (family flaviviridae) into human populations in 1957 and subsequent occurrence of seasonal outbreaks illustrate the key role that India's wild animals play in the emergence and reemergence of zoonotic pathogens. Other high priority zoonotic diseases of wildlife origin which could affect both livestock and humans include influenza, Nipah, Japanese encephalitis, rabies, plague, leptospirosis, anthrax and leishmaniasis. Continuous monitoring of India's extensively diverse and dispersed wildlife is challenging, but their use as indicators should facilitate efficient and rapid disease-outbreak response across the region and occasionally the globe. Defining and prioritizing research on zoonotic pathogens in wildlife are essential, particularly in a multidisciplinary one-world one-health approach which includes human and veterinary medical studies at the wildlife-livestock-human interfaces. This review indicates that wild animals play an important role in the emergence and re-emergence of zoonotic pathogens and provides brief summaries of the zoonotic diseases that have occurred in wild animals in India. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Selection to outsmart the germs: The evolution of disease recognition and social cognition.

    PubMed

    Kessler, Sharon E; Bonnell, Tyler R; Byrne, Richard W; Chapman, Colin A

    2017-07-01

    The emergence of providing care to diseased conspecifics must have been a turning point during the evolution of hominin sociality. On a population level, care may have minimized the costs of socially transmitted diseases at a time of increasing social complexity, although individual care-givers probably incurred increased transmission risks. We propose that care-giving likely originated within kin networks, where the costs may have been balanced by fitness increases obtained through caring for ill kin. We test a novel hypothesis of hominin cognitive evolution in which disease may have selected for the cognitive ability to recognize when a conspecific is infected. Because diseases may produce symptoms that are likely detectable via the perceptual-cognitive pathways integral to social cognition, we suggest that disease recognition and social cognition may have evolved together. Using agent-based modeling, we test 1) under what conditions disease can select for increasing disease recognition and care-giving among kin, 2) whether providing care produces greater selection for cognition than an avoidance strategy, and 3) whether care-giving alters the progression of the disease through the population. The greatest selection was produced by diseases with lower risks to the care-giver and prevalences low enough not to disrupt the kin networks. When care-giving and avoidance strategies were compared, only care-giving reduced the severity of the disease outbreaks and subsequent population crashes. The greatest selection for increased cognitive abilities occurred early in the model runs when the outbreaks and population crashes were most severe. Therefore, over the course of human evolution, repeated introductions of novel diseases into naïve populations could have produced sustained selection for increased disease recognition and care-giving behavior, leading to the evolution of increased cognition, social complexity, and, eventually, medical care in humans. Finally, we lay out predictions derived from our disease recognition hypothesis that we encourage paleoanthropologists, bioarchaeologists, primatologists, and paleogeneticists to test. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Meat and Nicotinamide: A Causal Role in Human Evolution, History, and Demographics

    PubMed Central

    Williams, Adrian C; Hill, Lisa J

    2017-01-01

    Hunting for meat was a critical step in all animal and human evolution. A key brain-trophic element in meat is vitamin B3 / nicotinamide. The supply of meat and nicotinamide steadily increased from the Cambrian origin of animal predators ratcheting ever larger brains. This culminated in the 3-million-year evolution of Homo sapiens and our overall demographic success. We view human evolution, recent history, and agricultural and demographic transitions in the light of meat and nicotinamide intake. A biochemical and immunological switch is highlighted that affects fertility in the ‘de novo’ tryptophan-to-kynurenine-nicotinamide ‘immune tolerance’ pathway. Longevity relates to nicotinamide adenine dinucleotide consumer pathways. High meat intake correlates with moderate fertility, high intelligence, good health, and longevity with consequent population stability, whereas low meat/high cereal intake (short of starvation) correlates with high fertility, disease, and population booms and busts. Too high a meat intake and fertility falls below replacement levels. Reducing variances in meat consumption might help stabilise population growth and improve human capital. PMID:28579800

  20. Reduced costs of reproduction in females mediate a shift from a male-biased to a female-biased lifespan in humans

    PubMed Central

    Bolund, Elisabeth; Lummaa, Virpi; Smith, Ken R.; Hanson, Heidi A.; Maklakov, Alexei A.

    2016-01-01

    The causes underlying sex differences in lifespan are strongly debated. While females commonly outlive males in humans, this is generally less pronounced in societies before the demographic transition to low mortality and fertility rates. Life-history theory suggests that reduced reproduction should benefit female lifespan when females pay higher costs of reproduction than males. Using unique longitudinal demographic records on 140,600 reproducing individuals from the Utah Population Database, we demonstrate a shift from male-biased to female-biased adult lifespans in individuals born before versus during the demographic transition. Only women paid a cost of reproduction in terms of shortened post-reproductive lifespan at high parities. Therefore, as fertility decreased over time, female lifespan increased, while male lifespan remained largely stable, supporting the theory that differential costs of reproduction in the two sexes result in the shifting patterns of sex differences in lifespan across human populations. Further, our results have important implications for demographic forecasts in human populations and advance our understanding of lifespan evolution. PMID:27087670

  1. Colon-specific delivery of lactobacillus rhamnosus GG using pectin hydrogel beads

    USDA-ARS?s Scientific Manuscript database

    The probiotic bacteria, Lactobacillus rhamnosus GG (LGG), has shown beneficial effects on human health, and is accepted by increasing populations for the prevention and treatment of irritable bowel diseases. To increase the bioavailability and efficacy of LGG, the probiotic was encapsulated in hydro...

  2. Effects of Culling on Leptospira interrogans Carriage by Rats

    PubMed Central

    Byers, Kaylee A.; Donovan, Christina M.; Bidulka, Julie J.; Stephen, Craig; Patrick, David M.; Himsworth, Chelsea G.

    2018-01-01

    We found that lethal, urban rat control is associated with a significant increase in the odds that surviving rats carry Leptospira interrogans. Our results suggest that human interventions have the potential to affect and even increase the prevalence of zoonotic pathogens within rat populations. PMID:29350160

  3. Deregulating Low-Risk Research

    ERIC Educational Resources Information Center

    Shamoo, Adil E.

    2007-01-01

    In the past few decades, with the explosion of biotechnology and the aging of the population, the use of human subjects in research has increased significantly. The United States has done much to protect human research subjects, and no one can deny the importance of keeping them safe. But at the same time, researchers whose work poses no threat to…

  4. Echinococcus multilocularis: An Emerging Pathogen in Hungary and Central Eastern Europe?

    PubMed Central

    Sréter, Tamás; Széll, Zoltán; Egyed, Zsuzsa

    2003-01-01

    Echinococcus multilocularis, the causative agent of human alveolar echinococcosis, is reported for the first time in Red Foxes (Vulpes vulpes) in Hungary. This parasite may be spreading eastward because the population of foxes has increased because of human interventions, and this spread may result in the emergence of alveolar echinococcosis in Central Eastern Europe. PMID:12643838

  5. The Changing Well-Being of Older Adult Registered Indians: An Analysis Using the Registered Indian Human Development Index

    ERIC Educational Resources Information Center

    Cooke, Martin; Guimond, Eric; McWhirter, Jennifer

    2008-01-01

    The demographic aging of the Registered Indian population suggests that the social, economic, and health conditions of older Registered Indians will be increasingly important for communities and policymakers. We have adapted the United Nations Development Program's Human Development Index using data from the Census of Canada and the Indian…

  6. Ecology of conflict: marine food supply affects human-wildlife interactions on land.

    PubMed

    Artelle, Kyle A; Anderson, Sean C; Reynolds, John D; Cooper, Andrew B; Paquet, Paul C; Darimont, Chris T

    2016-05-17

    Human-wildlife conflicts impose considerable costs to people and wildlife worldwide. Most research focuses on proximate causes, offering limited generalizable understanding of ultimate drivers. We tested three competing hypotheses (problem individuals, regional population saturation, limited food supply) that relate to underlying processes of human-grizzly bear (Ursus arctos horribilis) conflict, using data from British Columbia, Canada, between 1960-2014. We found most support for the limited food supply hypothesis: in bear populations that feed on spawning salmon (Oncorhynchus spp.), the annual number of bears/km(2) killed due to conflicts with humans increased by an average of 20% (6-32% [95% CI]) for each 50% decrease in annual salmon biomass. Furthermore, we found that across all bear populations (with or without access to salmon), 81% of attacks on humans and 82% of conflict kills occurred after the approximate onset of hyperphagia (July 1(st)), a period of intense caloric demand. Contrary to practices by many management agencies, conflict frequency was not reduced by hunting or removal of problem individuals. Our finding that a marine resource affects terrestrial conflict suggests that evidence-based policy for reducing harm to wildlife and humans requires not only insight into ultimate drivers of conflict, but also management that spans ecosystem and jurisdictional boundaries.

  7. Predicting the Spatial Distribution of Wolf (Canis lupus) Breeding Areas in a Mountainous Region of Central Italy

    PubMed Central

    Bassi, Elena; Willis, Stephen G.; Passilongo, Daniela; Mattioli, Luca; Apollonio, Marco

    2015-01-01

    Wolves (Canis lupus) in Italy represent a relict west European population. They are classified as vulnerable by IUCN, though have increased in number and expanded their range in recent decades. Here we use 17 years of monitoring data (from 1993 to 2010) collected in a mountainous region of central Italy (Arezzo, Tuscany) in an ecological niche-based model (MaxEnt) to characterize breeding sites (i.e. the areas where pups were raised) within home ranges, as detected from play-back responses. From a suite of variables related to topography, habitat and human disturbance we found that elevation and distance to protected areas were most important in explaining the locality of wolf responses. Rendezvous sites (family play-back response sites) typically occurred between 800 and 1200 m a.s.l., inside protected areas, and were usually located along mountain chains distant from human settlements and roads. In these areas human disturbance is low and the densities of ungulates are typically high. Over recent years, rendezvous sites have occurred closer to urban areas as the wolf population has continued to expand, despite the consequent human disturbance. This suggests that undisturbed landscapes may be reaching their carrying capacity for wolves. This, in turn, may lead to the potential for increased human-wolf interactions in future. Applying our model, both within and beyond the species’ current range, we identify sites both within the current range and also further afield, that the species could occupy in future. Our work underlines the importance of the present protected areas network in facilitating the recolonisation by wolves. Our projections of suitability of sites for future establishment as the population continues to expand could inform planning to minimize future wolf-human conflicts. PMID:26035174

  8. Possible mechanisms of mammalian immunocontraception.

    PubMed

    Barber, M R; Fayrer-Hosken, R A

    2000-03-01

    Ecological and conservation programs in ecosystems around the world have experienced varied success in population management. One of the greatest problems is that human expansion has led to the shrinking of wildlife habitat and, as a result, the overpopulation of many different species has occurred. The pressures exerted by the increased number of animals has caused environmental damage. The humane and practical control of these populations has solicited the scientific community to arrive at a safe, effective, and cost-efficient means of population control. Immunocontraception using zona pellucida antigens, specifically porcine zona pellucida (pZP), has become one of the most promising population control tools in the world today, with notable successes in horses and elephants. A conundrum has risen where pZP, a single vaccine, successfully induces an immunocontraceptive effect in multiple species of mammals. This review describes the most current data pertaining to the mammalian zona pellucida and immunocontraception, and from these studies, we suggest several potential mechanisms of immunocontraception.

  9. Dissection of complex adult traits in a mouse synthetic population.

    PubMed

    Burke, David T; Kozloff, Kenneth M; Chen, Shu; West, Joshua L; Wilkowski, Jodi M; Goldstein, Steven A; Miller, Richard A; Galecki, Andrzej T

    2012-08-01

    Finding the causative genetic variations that underlie complex adult traits is a significant experimental challenge. The unbiased search strategy of genome-wide association (GWAS) has been used extensively in recent human population studies. These efforts, however, typically find only a minor fraction of the genetic loci that are predicted to affect variation. As an experimental model for the analysis of adult polygenic traits, we measured a mouse population for multiple phenotypes and conducted a genome-wide search for effector loci. Complex adult phenotypes, related to body size and bone structure, were measured as component phenotypes, and each subphenotype was associated with a genomic spectrum of candidate effector loci. The strategy successfully detected several loci for the phenotypes, at genome-wide significance, using a single, modest-sized population (N = 505). The effector loci each explain 2%-10% of the measured trait variation and, taken together, the loci can account for over 25% of a trait's total population variation. A replicate population (N = 378) was used to confirm initially observed loci for one trait (femur length), and, when the two groups were merged, the combined population demonstrated increased power to detect loci. In contrast to human population studies, our mouse genome-wide searches find loci that individually explain a larger fraction of the observed variation. Also, the additive effects of our detected mouse loci more closely match the predicted genetic component of variation. The genetic loci discovered are logical candidates for components of the genetic networks having evolutionary conservation with human biology.

  10. The Use of Expert Opinion to Assess the Risk of Emergence or Re-Emergence of Infectious Diseases in Canada Associated with Climate Change

    PubMed Central

    Cox, Ruth; Revie, Crawford W.; Sanchez, Javier

    2012-01-01

    Global climate change is predicted to lead to an increase in infectious disease outbreaks. Reliable surveillance for diseases that are most likely to emerge is required, and given limited resources, policy decision makers need rational methods with which to prioritise pathogen threats. Here expert opinion was collected to determine what criteria could be used to prioritise diseases according to the likelihood of emergence in response to climate change and according to their impact. We identified a total of 40 criteria that might be used for this purpose in the Canadian context. The opinion of 64 experts from academic, government and independent backgrounds was collected to determine the importance of the criteria. A weight was calculated for each criterion based on the expert opinion. The five that were considered most influential on disease emergence or impact were: potential economic impact, severity of disease in the general human population, human case fatality rate, the type of climate that the pathogen can tolerate and the current climatic conditions in Canada. There was effective consensus about the influence of some criteria among participants, while for others there was considerable variation. The specific climate criteria that were most likely to influence disease emergence were: an annual increase in temperature, an increase in summer temperature, an increase in summer precipitation and to a lesser extent an increase in winter temperature. These climate variables were considered to be most influential on vector-borne diseases and on food and water-borne diseases. Opinion about the influence of climate on air-borne diseases and diseases spread by direct/indirect contact were more variable. The impact of emerging diseases on the human population was deemed more important than the impact on animal populations. PMID:22848536

  11. The Emergence and Maintenance of Vector-Borne Diseases in the Khyber Pakhtunkhwa Province, and the Federally Administered Tribal Areas of Pakistan

    PubMed Central

    Nieto, Nathan C.; Khan, Khalid; Uhllah, Ghufran; Teglas, Mike B.

    2012-01-01

    Human populations throughout much of the world are experiencing unprecedented changes in their relationship to the environment and their interactions with the animals with which so many humans are intimately dependent upon. These changes result not only from human induced changes in the climate, but also from population demographic changes due to wars, social unrest, behavioral changes resulting from cultural mixing, and large changes in land-use practices. Each of these social shifts can affect the maintenance and emergence of arthropod vectors disease or the pathogenic organisms themselves. A good example is the country of Pakistan, with a large rural population and developing urban economy, it also maintains a wide diversity of entomological disease vectors, including biting flies, mosquitoes, and ticks. Pathogens endemic to the region include the agents of piroplasmosis, rickettsiosis, spirochetosis, and viral hemorrhagic fevers and encephalitis. The northwestern region of the country, including the Khyber Pakhtunkhwa Province (KPK), formerly the North-West Frontier Provence (NWFP), and the Federally Administered Tribal Areas (FATA) are mountainous regions with a high degree of habitat diversity that has recently undergone a massive increase in human population density due to an immigrating refugee population from neighboring war-torn Afghanistan. Vector-borne diseases in people and livestock are common in KPK and FATA regions due to the limited use of vector control measures and access to livestock vaccines. The vast majority of people in this region live in abject poverty with >70% of the population living directly from production gained in animal husbandry. In many instances whole families live directly alongside their animal counterparts. In addition, there is little to no awareness of the threat posed by ticks and transmission of either zoonotic or veterinary pathogens. Recent emergence of Crimean–Congo hemorrhagic fever virus in rural populations, outbreaks of Dengue hemorrhagic fever have been reported in the region, and high prevalence of cattle infected and co-infected with multiple species of hemoparasites (Theileria, Babesia, Anaplasma). The emergence of which has followed the increased density of the rural population due to an influx of refugees from violent conflicts in Afghanistan and is exacerbated by an already impoverished society and wide diversity of potential arthropod vectors. These human outbreaks may be exacerbated by episodes of social upheaval but are also tied to the historically close association of people in the region with their livestock and subsequent zoonosis that result from spillover from co-habitation with infected domestic animals. PMID:22934007

  12. The emergence and maintenance of vector-borne diseases in the khyber pakhtunkhwa province, and the federally administered tribal areas of pakistan.

    PubMed

    Nieto, Nathan C; Khan, Khalid; Uhllah, Ghufran; Teglas, Mike B

    2012-01-01

    Human populations throughout much of the world are experiencing unprecedented changes in their relationship to the environment and their interactions with the animals with which so many humans are intimately dependent upon. These changes result not only from human induced changes in the climate, but also from population demographic changes due to wars, social unrest, behavioral changes resulting from cultural mixing, and large changes in land-use practices. Each of these social shifts can affect the maintenance and emergence of arthropod vectors disease or the pathogenic organisms themselves. A good example is the country of Pakistan, with a large rural population and developing urban economy, it also maintains a wide diversity of entomological disease vectors, including biting flies, mosquitoes, and ticks. Pathogens endemic to the region include the agents of piroplasmosis, rickettsiosis, spirochetosis, and viral hemorrhagic fevers and encephalitis. The northwestern region of the country, including the Khyber Pakhtunkhwa Province (KPK), formerly the North-West Frontier Provence (NWFP), and the Federally Administered Tribal Areas (FATA) are mountainous regions with a high degree of habitat diversity that has recently undergone a massive increase in human population density due to an immigrating refugee population from neighboring war-torn Afghanistan. Vector-borne diseases in people and livestock are common in KPK and FATA regions due to the limited use of vector control measures and access to livestock vaccines. The vast majority of people in this region live in abject poverty with >70% of the population living directly from production gained in animal husbandry. In many instances whole families live directly alongside their animal counterparts. In addition, there is little to no awareness of the threat posed by ticks and transmission of either zoonotic or veterinary pathogens. Recent emergence of Crimean-Congo hemorrhagic fever virus in rural populations, outbreaks of Dengue hemorrhagic fever have been reported in the region, and high prevalence of cattle infected and co-infected with multiple species of hemoparasites (Theileria, Babesia, Anaplasma). The emergence of which has followed the increased density of the rural population due to an influx of refugees from violent conflicts in Afghanistan and is exacerbated by an already impoverished society and wide diversity of potential arthropod vectors. These human outbreaks may be exacerbated by episodes of social upheaval but are also tied to the historically close association of people in the region with their livestock and subsequent zoonosis that result from spillover from co-habitation with infected domestic animals.

  13. Practical management of cumulative anthropogenic impacts with working marine examples.

    PubMed

    Wright, Andrew J; Kyhn, Line A

    2015-04-01

    Human pressure on the environment is expanding and intensifying, especially in coastal and offshore areas. Major contributors to this are the current push for offshore renewable energy sources, which are thought of as environmentally friendly sources of power, as well as the continued demand for petroleum. Human disturbances, including the noise almost ubiquitously associated with human activity, are likely to increase the incidence, magnitude, and duration of adverse effects on marine life, including stress responses. Stress responses have the potential to induce fitness consequences for individuals, which add to more obvious directed takes (e.g., hunting or fishing) to increase the overall population-level impact. To meet the requirements of marine spatial planning and ecosystem-based management, many efforts are ongoing to quantify the cumulative impacts of all human actions on marine species or populations. Meanwhile, regulators face the challenge of managing these accumulating and interacting impacts with limited scientific guidance. We believe there is scientific support for capping the level of impact for (at a minimum) populations in decline or with unknown statuses. This cap on impact can be facilitated through implementation of regular application cycles for project authorization or improved programmatic and aggregated impact assessments that simultaneously consider multiple projects. Cross-company collaborations and a better incorporation of uncertainty into decision making could also help limit, if not reduce, cumulative impacts of multiple human activities. These simple management steps may also form the basis of a rudimentary form of marine spatial planning and could be used in support of future ecosystem-based management efforts. © 2014 Society for Conservation Biology.

  14. Influence of population density on the concentration and speciation of metals in the soil and street dust from urban areas.

    PubMed

    Acosta, J A; Gabarrón, M; Faz, A; Martínez-Martínez, S; Zornoza, R; Arocena, J M

    2015-09-01

    Street dust and soil from high, medium and low populated cities and natural area were analysed for selected physical-chemical properties, total and chemical speciation of Zn, Pb, Cu, Cr, Cd, Co, Ni to understand the influence of human activities on metal accumulation and mobility in the environment. The pH, salinity, carbonates and organic carbon contents were similar between soil and dust from the same city. Population density increases dust/soil salinity but has no influence on metals concentrations in soils. Increases in metal concentrations with population density were observed in dusts. Cu, Zn, Pb, Cr can be mobilized more easily from dust compared to the soil. In addition, population density increase the percentage of Pb and Zn associated to reducible and carbonate phase in the dust. The behaviour of metals except Cd in soil is mainly affected by physico-chemical properties, while total metal influenced the speciation except Cr and Ni in dusts. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Population structure of the Chagas disease vector, Triatoma infestans, at the urban-rural interface.

    PubMed

    Foley, Erica A; Khatchikian, Camilo E; Hwang, Josephine; Ancca-Juárez, Jenny; Borrini-Mayori, Katty; Quıspe-Machaca, Victor R; Levy, Michael Z; Brisson, Dustin

    2013-10-01

    The increasing rate of biological invasions resulting from human transport or human-mediated changes to the environment has had devastating ecological and public health consequences. The kissing bug, Triatoma infestans, has dispersed through the Peruvian city of Arequipa. The biological invasion of this insect has resulted in a public health crisis, putting thousands of residents of this city at risk of infection by Trypanosoma cruzi and subsequent development of Chagas disease. Here, we show that populations of Tria. infestans in geographically distinct districts within and around this urban centre share a common recent evolutionary history although current gene flow is restricted even between proximal sites. The population structure among the Tria. infestans in different districts is not correlated with the geographical distance between districts. These data suggest that migration among the districts is mediated by factors beyond the short-range migratory capabilities of Tria. infestans and that human movement has played a significant role in the structuring of the Tria. infestans population in the region. Rapid urbanization across southern South America will continue to create suitable environments for Tria. infestans, and knowledge of its urban dispersal patterns may play a fundamental role in mitigating human disease risk. © 2013 John Wiley & Sons Ltd.

  16. Support from the relationship of genetic and geographic distance in human populations for a serial founder effect originating in Africa

    PubMed Central

    Ramachandran, Sohini; Deshpande, Omkar; Roseman, Charles C.; Rosenberg, Noah A.; Feldman, Marcus W.; Cavalli-Sforza, L. Luca

    2005-01-01

    Equilibrium models of isolation by distance predict an increase in genetic differentiation with geographic distance. Here we find a linear relationship between genetic and geographic distance in a worldwide sample of human populations, with major deviations from the fitted line explicable by admixture or extreme isolation. A close relationship is shown to exist between the correlation of geographic distance and genetic differentiation (as measured by FST) and the geographic pattern of heterozygosity across populations. Considering a worldwide set of geographic locations as possible sources of the human expansion, we find that heterozygosities in the globally distributed populations of the data set are best explained by an expansion originating in Africa and that no geographic origin outside of Africa accounts as well for the observed patterns of genetic diversity. Although the relationship between FST and geographic distance has been interpreted in the past as the result of an equilibrium model of drift and dispersal, simulation shows that the geographic pattern of heterozygosities in this data set is consistent with a model of a serial founder effect starting at a single origin. Given this serial-founder scenario, the relationship between genetic and geographic distance allows us to derive bounds for the effects of drift and natural selection on human genetic variation. PMID:16243969

  17. Human migration is important in the international spread of exotic Salmonella serovars in animal and human populations.

    PubMed

    Iveson, J B; Bradshaw, S D; How, R A; Smith, D W

    2014-11-01

    The exposure of indigenous humans and native fauna in Australia and the Wallacea zoogeographical region of Indonesia to exotic Salmonella serovars commenced during the colonial period and has accelerated with urbanization and international travel. In this study, the distribution and prevalence of exotic Salmonella serovars are mapped to assess the extent to which introduced infections are invading native wildlife in areas of high natural biodiversity under threat from expanding human activity. The major exotic Salmonella serovars, Bovismorbificans, Derby, Javiana, Newport, Panama, Saintpaul and Typhimurium, isolated from wildlife on populated coastal islands in southern temperate areas of Western Australia, were mostly absent from reptiles and native mammals in less populated tropical areas of the state. They were also not recorded on the uninhabited Mitchell Plateau or islands of the Bonaparte Archipelago, adjacent to south-eastern Indonesia. Exotic serovars were, however, isolated in wildlife on 14/17 islands sampled in the Wallacea region of Indonesia and several islands off the west coast of Perth. Increases in international tourism, involving islands such as Bali, have resulted in the isolation of a high proportion of exotic serovar infections suggesting that densely populated island resorts in the Asian region are acting as staging posts for the interchange of Salmonella infections between tropical and temperate regions.

  18. Global climate and infectious disease: The cholera paradigm

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Colwell, R.R.

    1996-12-20

    Historically, infectious diseases have had a profound effect on human populations, including their evolution and cultural development. Despite significant advances in medical science, infectious diseases continue to impact human populations in many parts of the world. Emerging diseases are considered to be those infections that either are newly appearing in the population or are rapidly increasing in incidence or expanding in geographic range. Emergence of disease is not a simple phenomenon, mainly because infectious diseases are dynamic. Most new infections are not caused by truly new pathogens but are microorganisms (viruses, bacteria, fungi, protozoa, and helminths) that find a newmore » way to enter a susceptible host and are newly recognized because of recently developed, sensitive techniques. Human activities drive emergence of disease and a variety of social, economic, political, climatic, technological, and environmental factors can shape the pattern of a disease and influence its emergence into populations. For example, travel affects emergence of disease, and human migrations have been the main source of epidemics throughout history. Trade caravans, religious pilgrimage, and military campaigns facilitated the spread of plague, smallpox, and cholera. Global travel is a fact of modern life and, equally so, the continued evolution of microorganisms; therefore, new infections will continue to emerge, and known infections will change in distribution, frequency, and severity. 88 refs., 1 fig.« less

  19. Human impacts drive a global topographic signature in tree cover.

    PubMed

    Sandel, Brody; Svenning, Jens-Christian

    2013-01-01

    The Anthropocene is a geological epoch marked by major human influences on processes in the atmosphere, biosphere, hydrosphere and geosphere. One of the most dramatic features of the Anthropocene is the massive alteration of the Earth's vegetation, including forests. Here we investigate the role of topography in shaping human impacts on tree cover from local to global scales. We show that human impacts have resulted in a global tendency for tree cover to be constrained to sloped terrain and losses to be concentrated on flat terrain. This effect increases in strength with increasing human pressure and is most pronounced in countries with rapidly growing economies, limited human population stress and highly effective governments. These patterns likely reflect the relative inaccessibility of sloped topography and have important implications for conservation and modelling of future tree cover.

  20. HLA genetic diversity in Hungarians and Hungarian Gypsies: complementary differentiation patterns and demographic signals revealed by HLA-A, -B and -DRB1 in Central Europe.

    PubMed

    Inotai, D; Szilvasi, A; Benko, S; Boros-Major, A; Illes, Z; Bors, A; Kiss, K P; Rajczy, K; Gelle-Hossó, A; Buhler, S; Nunes, J M; Sanchez-Mazas, A; Tordai, A

    2015-08-01

    Systematic analyses of human leukocyte antigen (HLA) profiles in different populations may increase the efficiency of bone marrow donor selection and help reconstructing human peopling history. We typed HLA-A, -B, and -DRB1 allele groups in two bone marrow donor cohorts of 2402 Hungarians and 186 Hungarian Gypsies and compared them with several Central-European, Spanish Gypsy, and Indian populations. Our results indicate that different European Gypsy populations share a common origin but diverged genetically as a consequence of founder effect and rapid genetic drift, whereas other European populations are related genetically in relation to geography. This study also suggests that while HLA-A accurately depicts the effects of genetic drift, HLA-B, and -DRB1 conserve more signatures of ancient population relationships, as a result of balancing selection. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Invasive wisteria in the Southeastern United StateS: genetic diversity, hybridization and the role of urban centers

    Treesearch

    Jennifer L. Trusty; Leslie R. Goertzen; Wayne C. Zipperer; B Graeme Lockaby

    2007-01-01

    The increasing numbers and negative impacts of invasive species have prompted research on the relationship between human activities and the success of invasive horticultural plants. In this study, we use population genetic relationships to model the escape of a common garden vine, exotic Wisteria, into natural habitats. Urban and naturalized Wisteria populations in...

  2. Bioenergy Tree Plantations in the Tropics: Ecological Implications and Impacts. Commission on Ecology Paper Number 12.

    ERIC Educational Resources Information Center

    Davidson, J.

    Uneven economic growth, rapid population increases, and high costs of fossil fuels have caused much of the human race to experience an energy crisis. For the world's poor people the energy requirements consist mainly of firewood. This crisis will be aggravated further as population trends begin to overwhelm natural resources. Future demands for…

  3. A transdisciplinary approach to the initial validation of a single cell protein as an alternative protein source for use in aquafeeds

    USDA-ARS?s Scientific Manuscript database

    The human population is growing and, globally, we must meet the challenge of increased protein needs required to feed this population. Single cell proteins (SCP), when coupled to aquaculture production, offers a means to ensure future protein needs can be met without direct competition with food for...

  4. Effects of urban land-use change on biogeochemical cycles

    Treesearch

    Richard V. Pouyat; Diane E. Pataki; Kenneth T. Belt; Peter M. Groffman; John Hom; Lawrence E. Band

    2007-01-01

    Urban land-use change, the conversion of agricultural recand natural ecosystems to human settlements, has become an important component of global change. Virtually all of the projected increase in the world's population is expected to occur in cities so that by the year 2007 more than half of the global population is expected to live in urban areas (United Nations...

  5. Worldwide analysis of multiple microsatellites: language diversity has a detectable influence on DNA diversity.

    PubMed

    Belle, Elise M S; Barbujani, Guido

    2007-08-01

    Previous studies of the correlations between the languages spoken by human populations and the genes carried by the members of those populations have been limited by the small amount of genetic markers available and by approximations in the treatment of linguistic data. In this study we analyzed a large collection of polymorphic microsatellite loci (377), distributed on all autosomes, and used Ruhlen's linguistic classification, to investigate the relative roles of geography and language in shaping the distribution of human DNA diversity at a worldwide scale. For this purpose, we performed three different kinds of analysis: (i) we partitioned genetic variances at three hierarchical levels of population subdivision according to language group by means of a molecular analysis of variance (AMOVA); (ii) we quantified by a series of Mantel's tests the correlation between measures of genetic and linguistic differentiation; and (iii) we tested whether linguistic differences are increased across known zones of increased genetic change between populations. Genetic differences appear to more closely reflect geographic than linguistic differentiation. However, our analyses show that language differences also have a detectable effect on DNA diversity at the genomic level, above and beyond the effects of geographic distance. (c) 2007 Wiley-Liss, Inc.

  6. Beyond Population Distribution: Enhancing Sociocultural Resolution from Remote Sensing

    NASA Astrophysics Data System (ADS)

    Bhaduri, B. L.; Rose, A.

    2017-12-01

    At Oak Ridge National Laboratory, since late 1990s, we have focused on developing high resolution population distribution and dynamics data from local to global scales. Increasing resolutions of geographic data has been mirrored by population data sets developed across the community. However, attempts to increase temporal and sociocultural resolutions have been limited given the lack of high resolution data on human settlements and activities. While recent advancements in moderate to high resolution earth observation have led to better physiographic data, the approach of exploiting very high resolution (sub-meter resolution) imagery has also proven useful for generating accurate human settlement maps. It allows potential (social and vulnerability) characterization of population from settlement structures by exploiting image texture and spectral features. Our recent research utilizing machine learning and geocomputation has not only validated "poverty mapping from imagery" hypothesis, but has delineated a new paradigm of rapid analysis of high resolution imagery to enhance such "neighborhood" mapping techniques. Such progress in GIScience is allowing us to move towards the goal of creating a global foundation level database for impervious surfaces and "neighborhoods," and holds tremendous promise for key applications focusing on sustainable development including many social science applications.

  7. The effect of changes in health sector resources on infant mortality in the short-run and the long-run: a longitudinal econometric analysis.

    PubMed

    Farahani, Mansour; Subramanian, S V; Canning, David

    2009-06-01

    While countries with higher levels of human resources for health typically have better population health, the evidence that increases in the level of human resources for health leads to improvements in population health is limited. We use a dynamic regression model to obtain estimates of both the short-run and long-term effects of changes in physicians per capita, our measure of health system resources, on infant mortality. Using a dataset of 99 countries at 5-year intervals from 1960-2000, we estimate that increasing the number of physicians by one per 1000 population (roughly a doubling of current levels of provision) decreases the infant mortality rate by 15% within 5 years and by 45% in the long-run with half the long-run gain being achieved in 15 years. We conclude that the long-run effects of heath system resources are substantially larger than previously estimated. Our results suggest, however, that countries that have delayed action on the Millennium Development Goal of reducing infant and child mortality rate by two-thirds by 2015 (relative to 1990) may have difficulty meeting this goal even if they rapidly increase resources now.

  8. Modelling hydrological changes in surface in relation with anthropogenic drivers and consequences on human health and local economic

    NASA Astrophysics Data System (ADS)

    Sandoz, Alain; Leblond, Agnès; Boutron, Olivier

    2016-04-01

    Marais des Baux are located between Alpilles in the North and the plain of the Crau (South-East) of the town of Arles, in the South of France. Already built in Roman times, swamps located at the outlet of the Baux valley basin have experienced an increased human pressure during last centuries. Apotheosis of human development is the period of post-war with Marshall Plan and the development of the Common Agricultural Policy (CAP). At the beginning of the 21st century, inverse hydrologic dynamic is observed. Renaturation of the lower parts of the marshes, where land is less profitable, has reversed the trend of previous centuries. To be sustainable, this annealing must be accompanied by water governance at the watershed scale. This work aims to help policy makers and managers to good governance of the territory. Hierarchical multi-scale approach has enabled a better understanding of hydrological flows. In addition, knowledge of different actors' strategies is not enough. There may be different interests and strategies within the same group of actors. In this case, this is what we observe between farmers located on the upstream parts of the watershed eager, for some, to increase irrigation, and those located downstream, in the marshes, forced pump to maintain water levels corresponding to the expectations of the majority of the actors. On the other hand, there is a negative image of still marsh near a rural population and new rural population. Decreasing pumping or to send a higher volume of water could significantly increase flooded areas. This increase in flooded areas could facilitate the development of certain mosquito species. These mosquitoes not only represent a potential health risk for human populations but also increase the discomfort felt by the local population and tourists. This discomfort may also have an impact on economic activity linked with tourism. The work allowed the testing of different scenarios of flooding, according to the hydraulic management of the watershed. The modeling also performed to simulate a change in rainfall locally to measure hydrological and environmental consequences. According to these scenarios, it was possible to map the potential areas of mosquitoes breeding sites (presence / absence of mosquitoes) and their impact on urban populations in terms of health risks and nuisance. This territory represents many interests for decision-makers interested in issues of governance and renaturation. To improve the inclusion of better water governance and territories, as well as facilitate dynamic annealing, it might be necessary to help decision-makers having a better knowledge of the impact of human drivers on water management on the territory. This increased knowledge would also enable local decision-makers to improve their awareness of the heritage and biodiversity of wetlands. This project was funded by the French Ministry of Ecology, Sustainable Development and Energy as part of the projects Water and Territories.

  9. The Big Picture.

    ERIC Educational Resources Information Center

    Naturescope, 1987

    1987-01-01

    Contains a series of activities which focus on the process of extinction, how the increasing human population affects other species, and on the reasons for helping endangered species. Includes diagrams and illustrations of endangered species. (ML)

  10. A meta-analysis of human disturbance impacts on Antarctic wildlife.

    PubMed

    Coetzee, Bernard W T; Chown, Steven L

    2016-08-01

    Evidence-based assessments are increasingly recognized as the best-practice approach to determine appropriate conservation interventions, but such assessments of the impact of human disturbance on wildlife are rare. Human disturbance comprises anthropogenic activities that are typically non-lethal, but may cause short- and/or longer-term stress and fitness responses in wildlife. Expanding human activity in the Antarctic region is of particular concern because it increases the scope and potential for increased human disturbance to wildlife in a region that is often thought of as relatively untouched by anthropogenic influences. Here, we use a meta-analytical approach to synthesise research on human disturbance to wildlife over the last three decades in the Antarctic and sub-Antarctic region. We combine data from 62 studies across 21 species on the behavioural, physiological and population responses of wildlife to pedestrian, vehicle and research disturbances. The overall effect size indicated a small, albeit statistically significant negative effect of disturbance (-0.39; 95% CI: -0.60 to -0.18). Negative effects were found for both physiological and population responses, but no evidence was found for a significant impact on wildlife behavioural responses. Negative effects were found across pedestrian, vehicle and research disturbances. Significant and high among-study heterogeneity was found in both disturbance and response sub-groups. Among species, it remains unclear to what extent different forms of disturbance translate into negative population responses. Most current guidelines to limit wildlife disturbance impacts in Antarctica recommend that approaches be tailored to animal behavioural cues, but our work demonstrates that behavioural changes do not necessarily reflect more cryptic, and more deleterious impacts, such as changes in physiology. In consequence, we recommend that pedestrian approach guidelines in the Antarctic region be revisited. Due to the high heterogeneity in effects, management guidelines for different sites and species will need to be developed on a case-by-case basis, ideally in conjunction with carefully designed experiments. Guidelines to reduce the impact of research activities per se require development to reduce the potential impacts of conducting research. We identify research questions that, if answered, will further improve the evidence base for guidelines to manage human disturbance in Antarctica. © 2015 Cambridge Philosophical Society.

  11. Early animal farming and zoonotic disease dynamics: modelling brucellosis transmission in Neolithic goat populations.

    PubMed

    Fournié, Guillaume; Pfeiffer, Dirk U; Bendrey, Robin

    2017-02-01

    Zoonotic pathogens are frequently hypothesized as emerging with the origins of farming, but evidence of this is elusive in the archaeological records. To explore the potential impact of animal domestication on zoonotic disease dynamics and human infection risk, we developed a model simulating the transmission of Brucella melitensis within early domestic goat populations. The model was informed by archaeological data describing goat populations in Neolithic settlements in the Fertile Crescent, and used to assess the potential of these populations to sustain the circulation of Brucella . Results show that the pathogen could have been sustained even at low levels of transmission within these domestic goat populations. This resulted from the creation of dense populations and major changes in demographic characteristics. The selective harvesting of young male goats, likely aimed at improving the efficiency of food production, modified the age and sex structure of these populations, increasing the transmission potential of the pathogen within these populations. Probable interactions between Neolithic settlements would have further promoted pathogen maintenance. By fostering conditions suitable for allowing domestic goats to become reservoirs of Brucella melitensis , the early stages of agricultural development were likely to promote the exposure of humans to this pathogen.

  12. Early animal farming and zoonotic disease dynamics: modelling brucellosis transmission in Neolithic goat populations

    PubMed Central

    Pfeiffer, Dirk U.; Bendrey, Robin

    2017-01-01

    Zoonotic pathogens are frequently hypothesized as emerging with the origins of farming, but evidence of this is elusive in the archaeological records. To explore the potential impact of animal domestication on zoonotic disease dynamics and human infection risk, we developed a model simulating the transmission of Brucella melitensis within early domestic goat populations. The model was informed by archaeological data describing goat populations in Neolithic settlements in the Fertile Crescent, and used to assess the potential of these populations to sustain the circulation of Brucella. Results show that the pathogen could have been sustained even at low levels of transmission within these domestic goat populations. This resulted from the creation of dense populations and major changes in demographic characteristics. The selective harvesting of young male goats, likely aimed at improving the efficiency of food production, modified the age and sex structure of these populations, increasing the transmission potential of the pathogen within these populations. Probable interactions between Neolithic settlements would have further promoted pathogen maintenance. By fostering conditions suitable for allowing domestic goats to become reservoirs of Brucella melitensis, the early stages of agricultural development were likely to promote the exposure of humans to this pathogen. PMID:28386446

  13. Disaggregating census data for population mapping using random forests with remotely-sensed and ancillary data.

    PubMed

    Stevens, Forrest R; Gaughan, Andrea E; Linard, Catherine; Tatem, Andrew J

    2015-01-01

    High resolution, contemporary data on human population distributions are vital for measuring impacts of population growth, monitoring human-environment interactions and for planning and policy development. Many methods are used to disaggregate census data and predict population densities for finer scale, gridded population data sets. We present a new semi-automated dasymetric modeling approach that incorporates detailed census and ancillary data in a flexible, "Random Forest" estimation technique. We outline the combination of widely available, remotely-sensed and geospatial data that contribute to the modeled dasymetric weights and then use the Random Forest model to generate a gridded prediction of population density at ~100 m spatial resolution. This prediction layer is then used as the weighting surface to perform dasymetric redistribution of the census counts at a country level. As a case study we compare the new algorithm and its products for three countries (Vietnam, Cambodia, and Kenya) with other common gridded population data production methodologies. We discuss the advantages of the new method and increases over the accuracy and flexibility of those previous approaches. Finally, we outline how this algorithm will be extended to provide freely-available gridded population data sets for Africa, Asia and Latin America.

  14. 42 CFR 403.320 - CMS review and monitoring of State systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Section 403.320 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN... apply. (v) Any allowance for anticipated growth in the amount of services from the base year (if applicable, the allowance must be presented in separate estimates for population increases or for increases...

  15. 42 CFR 403.320 - CMS review and monitoring of State systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Section 403.320 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN... apply. (v) Any allowance for anticipated growth in the amount of services from the base year (if applicable, the allowance must be presented in separate estimates for population increases or for increases...

  16. Mapping QTL and identification of genes associated with drought resistance in sorghum

    USDA-ARS?s Scientific Manuscript database

    Water limits global agricultural production and the global increasing aridity, growing human population, and the depletion of aquifers will only increase its scarcity for agriculture. Water is essential for plant growth and in areas that are prone to drought, the use of drought resistant crops is a ...

  17. Climate change in the North American Arctic: A one health perspective

    USDA-ARS?s Scientific Manuscript database

    Climate change is expected to increase the prevalence of acute and chronic diseases among human and animal populations within the Arctic and sub-Arctic latitudes of North America. Warmer temperatures are expected to increase disease risks from food-borne pathogens, water-borne diseases, and vector-...

  18. Understanding the yield gap in wheat production

    USDA-ARS?s Scientific Manuscript database

    Wheat production around the globe is a staple of human nutrition needs and will continue to provide a major component of global food security. The increases in world population demand that we continue to increase wheat production in a sustainable manner. To achieve this goal requires that we underst...

  19. Climate, CO2, and demographic impacts on global wildfire emissions

    NASA Astrophysics Data System (ADS)

    Knorr, W.; Jiang, L.; Arneth, A.

    2015-09-01

    Wildfires are by far the largest contributor to global biomass burning and constitute a large global source of atmospheric traces gases and aerosols. Such emissions have a considerable impact on air quality and constitute a major health hazard. Biomass burning also influences the radiative balance of the atmosphere and is thus not only of societal, but also of significant scientific interest. There is a common perception that climate change will lead to an increase in emissions as hot and dry weather events that promote wildfire will become more common. However, even though a few studies have found that the inclusion of CO2 fertilization of photosynthesis and changes in human population patterns will tend to somewhat lower predictions of future wildfire emissions, no such study has included full ensemble ranges of both climate predictions and population projections, including the effect of different degrees of urbanisation. Here, we present a series of 124 simulations with the LPJ-GUESS-SIMFIRE global dynamic vegetation - wildfire model, including a semi-empirical formulation for the prediction of burned area based on fire weather, fuel continuity and human population density. The simulations comprise Climate Model Intercomparison Project 5 (CMIP5) climate predictions from eight Earth system models using two Representative Concentration Pathways (RCPs) and five scenarios of future human population density based on the series of Shared Socioeconomic Pathways (SSPs), sensitivity tests for the effect of climate and CO2, as well as a sensitivity analysis using two alternative parameterisations of the semi-empirical burned-area model. Contrary to previous work, we find no clear future trend of global wildfire emissions for the moderate emissions and climate change scenario based on the RCP 4.5. Only historical population change introduces a decline by around 15 % since 1900. Future emissions could either increase for low population growth and fast urbanisation, or continue to decline for high population growth and slow urbanisation. Only for high future climate change (RCP8.5), wildfire emissions start to rise again after ca. 2020 but are unlikely to reach the levels of 1900 by the end of the 21st century. We find that climate warming will generally increase the risk of fire, but that this is only one of several equally important factors driving future levels of wildfire emissions, which include population change, CO2 fertilisation causing woody thickening, increased productivity and fuel load, and faster litter turnover in a warmer climate.

  20. Settlement scaling and increasing returns in an ancient society

    PubMed Central

    Ortman, Scott G.; Cabaniss, Andrew H. F.; Sturm, Jennie O.; Bettencourt, Luís M. A.

    2015-01-01

    A key property of modern cities is increasing returns to scale—the finding that many socioeconomic outputs increase more rapidly than their population size. Recent theoretical work proposes that this phenomenon is the result of general network effects typical of human social networks embedded in space and, thus, is not necessarily limited to modern settlements. We examine the extent to which increasing returns are apparent in archaeological settlement data from the pre-Hispanic Basin of Mexico. We review previous work on the quantitative relationship between population size and average settled area in this society and then present a general analysis of their patterns of monument construction and house sizes. Estimated scaling parameter values and residual statistics support the hypothesis that increasing returns to scale characterized various forms of socioeconomic production available in the archaeological record and are found to be consistent with key expectations from settlement scaling theory. As a consequence, these results provide evidence that the essential processes that lead to increasing returns in contemporary cities may have characterized human settlements throughout history, and demonstrate that increasing returns do not require modern forms of political or economic organization. PMID:26601129

  1. Two-dimensional analysis of human lymphocyte proteins. III. Preliminary report on a marker for the early detection and diagnosis of infectious mononucleosis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Willard, K.E.

    1982-04-01

    Two-dimensional gel electrophoretic patterns of human peripheral blood leukocytes from 12 patients with infectious mononucleosis were prepared by use of the ISO-DALT system. Before the two-dimensional separation, the leukocytes were purified by Ficoll-Paque gradient centrifugation and labeled overnight with (/sup 35/S) methionine. Quantitative increases in two proteins were detected in the patterns of infected leukocytes from the patients as compared with controls. Fluorescence-activated cell sorting of leukocytes from normal human peripheral blood before subsequent two-dimensional gel analysis revealed that the dramatic increase in one of these proteins (Inmono:2) could be due to shifts in the population ratios of lymphocytes, monocytes,more » and granulocytes. In contrast, the appearance in the infected leukocytes of a second protein, Inmono:1, could not be accounted for by cell-population shifts. Increased amounts of these two proteins have been found in every patient studied who had clinically detectable infectious mononucleosis. In addition, a patient who displayed symptoms of infectious mononucleosis but who did not have a positive result in the MONOSPOT test (Ortho) until three weeks after our analysis also demonstrated increased relative amounts of these proteins in his leukocyte pattern.« less

  2. Two independent apolipoprotein A5 haplotypes influence human plasma triglyceride levels.

    PubMed

    Pennacchio, Len A; Olivier, Michael; Hubacek, Jaroslav A; Krauss, Ronald M; Rubin, Edward M; Cohen, Jonathan C

    2002-11-15

    The recently identified apolipoprotein A5 gene (APOA5) has been shown to play an important role in determining plasma triglyceride concentrations in humans and mice. We previously identified an APOA5 haplotype (designated APOA5*2) that is present in approximately 16% of Caucasians and is associated with increased plasma triglyceride concentrations. In this report we describe another APOA5 haplotype (APOA5*3) containing the rare allele of the single nucleotide polymorphism c.56C>G that changes serine to tryptophan at codon 19 and is independently associated with high plasma triglyceride levels in three different populations. In a sample of 264 Caucasian men and women with plasma triglyceride concentrations above the 90th percentile or below the 10th percentile, the APOA5*3 haplotype was more than three-fold more common in the group with high plasma triglyceride levels. In a second independently ascertained sample of Caucasian men and women (n=419) who were studied while consuming their self-selected diets as well as after high-carbohydrate diets and high-fat diets, the APOA5*3 haplotype was associated with increased plasma triglyceride levels on all three dietary regimens. In a third population comprising 2660 randomly selected individuals, the APOA5*3 haplotype was found in 12% of Caucasians, 14% of African-Americans and 28% of Hispanics and was associated with increased plasma triglyceride levels in both men and women in each ethnic group. These findings establish that the APOA5 locus contributes significantly to inter-individual variation in plasma triglyceride levels in humans. Together, the APOA5*2 and APOA5*3 haplotypes are found in 25-50% of African-Americans, Hispanics and Caucasians and support the contribution of common human variation to quantitative phenotypes in the general population.

  3. Phantoms of the forest: legacy risk effects of a regionally extinct large carnivore.

    PubMed

    Sahlén, Ellinor; Noell, Sonja; DePerno, Christopher S; Kindberg, Jonas; Spong, Göran; Cromsigt, Joris P G M

    2016-02-01

    The increased abundance of large carnivores in Europe is a conservation success, but the impact on the behavior and population dynamics of prey species is generally unknown. In Europe, the recolonization of large carnivores often occurs in areas where humans have greatly modified the landscape through forestry or agriculture. Currently, we poorly understand the effects of recolonizing large carnivores on extant prey species in anthropogenic landscapes. Here, we investigated if ungulate prey species showed innate responses to the scent of a regionally exterminated but native large carnivore, and whether the responses were affected by human-induced habitat openness. We experimentally introduced brown bear Ursus arctos scent to artificial feeding sites and used camera traps to document the responses of three sympatric ungulate species. In addition to controls without scent, reindeer scent Rangifer tarandus was used as a noncarnivore, novel control scent. Fallow deer Dama dama strongly avoided areas with bear scent. In the presence of bear scent, all ungulate species generally used open sites more than closed sites, whereas the opposite was observed at sites with reindeer scent or without scent. The opening of forest habitat by human practices, such as forestry and agriculture, creates a larger gradient in habitat openness than available in relatively unaffected closed forest systems, which may create opportunities for prey to alter their habitat selection and reduce predation risk in human-modified systems that do not exist in more natural forest systems. Increased knowledge about antipredator responses in areas subjected to anthropogenic change is important because these responses may affect prey population dynamics, lower trophic levels, and attitudes toward large carnivores. These aspects may be of particular relevance in the light of the increasing wildlife populations across much of Europe.

  4. Demographic and ecological risk factors for human influenza A virus infections in rural Indonesia.

    PubMed

    Root, Elisabeth Dowling; Agustian, Dwi; Kartasasmita, Cissy; Uyeki, Timothy M; Simões, Eric A F

    2017-09-01

    Indonesia has the world's highest reported mortality for human infections with highly pathogenic avian influenza (HPAI) A(H5N1) virus. Indonesia is an agriculturally driven country where human-animal mixing is common and provides a unique environment for zoonotic influenza A virus transmission. To identify potential demographic and ecological risk factors for human infection with seasonal influenza A viruses in rural Indonesia, a population-based study was conducted in Cileunyi and Soreang subdistricts near Bandung in western Java from 2008 to 2011. Passive influenza surveillance with RT-PCR confirmation of influenza A viral RNA in respiratory specimens was utilized for case ascertainment. A population census and mapping were utilized for population data collection. The presence of influenza A(H3N2) and A(H1N1)pdm09 virus infections in a household was modeled using Generalized Estimating Equations. Each additional child aged <5 years in a household increased the odds of H3N2 approximately 5 times (OR=4.59, 95%CI: 3.30-6.24) and H1N1pdm09 by 3.5 times (OR=3.53, 95%CI: 2.51-4.96). In addition, the presence of 16-30 birds in the house was associated with an increased odds of H3N2 (OR=5.08, 95%CI: 2.00-12.92) and H1N1pdm09 (OR=12.51 95%CI: 6.23-25.13). Our findings suggest an increase in influenza A virus infections in rural Indonesian households with young children and poultry. © 2017 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

  5. Modeling the Pre-Industrial Roots of Modern Super-Exponential Population Growth

    PubMed Central

    Stutz, Aaron Jonas

    2014-01-01

    To Malthus, rapid human population growth—so evident in 18th Century Europe—was obviously unsustainable. In his Essay on the Principle of Population, Malthus cogently argued that environmental and socioeconomic constraints on population rise were inevitable. Yet, he penned his essay on the eve of the global census size reaching one billion, as nearly two centuries of super-exponential increase were taking off. Introducing a novel extension of J. E. Cohen's hallmark coupled difference equation model of human population dynamics and carrying capacity, this article examines just how elastic population growth limits may be in response to demographic change. The revised model involves a simple formalization of how consumption costs influence carrying capacity elasticity over time. Recognizing that complex social resource-extraction networks support ongoing consumption-based investment in family formation and intergenerational resource transfers, it is important to consider how consumption has impacted the human environment and demography—especially as global population has become very large. Sensitivity analysis of the consumption-cost model's fit to historical population estimates, modern census data, and 21st Century demographic projections supports a critical conclusion. The recent population explosion was systemically determined by long-term, distinctly pre-industrial cultural evolution. It is suggested that modern globalizing transitions in technology, susceptibility to infectious disease, information flows and accumulation, and economic complexity were endogenous products of much earlier biocultural evolution of family formation's embeddedness in larger, hierarchically self-organizing cultural systems, which could potentially support high population elasticity of carrying capacity. Modern super-exponential population growth cannot be considered separately from long-term change in the multi-scalar political economy that connects family formation and intergenerational resource transfers to wider institutions and social networks. PMID:25141019

  6. Suburbanization, estrogen contamination, and sex ratio in wild amphibian populations.

    PubMed

    Lambert, Max R; Giller, Geoffrey S J; Barber, Larry B; Fitzgerald, Kevin C; Skelly, David K

    2015-09-22

    Research on endocrine disruption in frog populations, such as shifts in sex ratios and feminization of males, has predominantly focused on agricultural pesticides. Recent evidence suggests that suburban landscapes harbor amphibian populations exhibiting similar levels of endocrine disruption; however the endocrine disrupting chemical (EDC) sources are unknown. Here, we show that sex ratios of metamorphosing frogs become increasingly female-dominated along a suburbanization gradient. We further show that suburban ponds are frequently contaminated by the classical estrogen estrone and a variety of EDCs produced by plants (phytoestrogens), and that the diversity of organic EDCs is correlated with the extent of developed land use and cultivated lawn and gardens around a pond. Our work also raises the possibility that trace-element contamination associated with human land use around suburban ponds may be contributing to the estrogenic load within suburban freshwaters and constitutes another source of estrogenic exposure for wildlife. These data suggest novel, unexplored pathways of EDC contamination in human-altered environments. In particular, we propose that vegetation changes associated with suburban neighborhoods (e.g., from forests to lawns and ornamental plants) increase the distribution of phytoestrogens in surface waters. The result of frog sex ratios varying as a function of human land use implicates a role for environmental modulation of sexual differentiation in amphibians, which are assumed to only have genetic sex determination. Overall, we show that endocrine disruption is widespread in suburban frog populations and that the causes are likely diverse.

  7. Suburbanization, estrogen contamination, and sex ratio in wild amphibian populations

    USGS Publications Warehouse

    Lambert, Max R.; Giller, Geoffrey S. J.; Barber, Larry B.; Fitzgerald, Kevin C.; Skelly, David K.

    2015-01-01

    Research on endocrine disruption in frog populations, such as shifts in sex ratios and feminization of males, has predominantly focused on agricultural pesticides. Recent evidence suggests that suburban landscapes harbor amphibian populations exhibiting similar levels of endocrine disruption; however the endocrine disrupting chemical (EDC) sources are unknown. Here, we show that sex ratios of metamorphosing frogs become increasingly female-dominated along a suburbanization gradient. We further show that suburban ponds are frequently contaminated by the classical estrogen estrone and a variety of EDCs produced by plants (phytoestrogens), and that the diversity of organic EDCs is correlated with the extent of developed land use and cultivated lawn and gardens around a pond. Our work also raises the possibility that trace-element contamination associated with human land use around suburban ponds may be contributing to the estrogenic load within suburban freshwaters and constitutes another source of estrogenic exposure for wildlife. These data suggest novel, unexplored pathways of EDC contamination in human-altered environments. In particular, we propose that vegetation changes associated with suburban neighborhoods (e.g., from forests to lawns and ornamental plants) increase the distribution of phytoestrogens in surface waters. The result of frog sex ratios varying as a function of human land use implicates a role for environmental modulation of sexual differentiation in amphibians, which are assumed to only have genetic sex determination. Overall, we show that endocrine disruption is widespread in suburban frog populations and that the causes are likely diverse.

  8. Art meets science: The Cosmopolitan Chicken Research Project.

    PubMed

    Stinckens, A; Vereijken, A; Ons, E; Konings, P; Van As, P; Cuppens, H; Moreau, Y; Sakai, R; Aerts, J; Goddeeris, B; Buys, N; Vanmechelen, K; Cassiman, J J

    2015-01-01

    The Cosmopolitan Chicken Project is an artistic undertaking of renowned artist Koen Vanmechelen. In this project, the artist interbreeds domestic chickens from different countries aiming at the creation of a true Cosmopolitan Chicken as a symbol for global diversity. The unifying theme is the chicken and the egg, symbols that link scientific, political, philosophical and ethical issues. The Cosmopolitan Chicken Research Project is the scientific component of this artwork. Based on state of the art genomic techniques, the project studies the effect of the crossing of chickens on the genetic diversity. Also, this research is potentially applicable to the human population. The setup of the CC®P is quite different from traditional breeding experiments: starting from the crossbreed of two purebred chickens (Mechelse Koekoek x Poule de Bresse), every generation is crossed with a few animals from another breed. For 26 of these purebred and crossbred populations, genetic diversity was measured (1) under the assumption that populations were sufficiently large to maintain all informative SNP within a generation and (2) under the circumstances of the CCP breeding experiment. Under the first assumption, a steady increase in genetic diversity was witnessed over the consecutive generations, thus indeed indicating the creation of a "Cosmopolitan Chicken Genome". However, under the conditions of the CCP, which reflects the reality within the human population, diversity is seen to fluctuate within given boundaries instead of steadily increasing. A reflection on this might be that this is because, in humans, an evolutionary optimum in genetic diversity is reached. Key words.

  9. Changes in human gut flora with age: an Indian familial study.

    PubMed

    Marathe, Nachiket; Shetty, Sudarshan; Lanjekar, Vikram; Ranade, Dilip; Shouche, Yogesh

    2012-09-26

    The gut micro flora plays vital role in health status of the host. The majority of microbes residing in the gut have a profound influence on human physiology and nutrition. Different human ethnic groups vary in genetic makeup as well as the environmental conditions they live in. The gut flora changes with genetic makeup and environmental factors and hence it is necessary to understand the composition of gut flora of different ethnic groups. Indian population is different in physiology from western population (YY paradox) and thus the gut flora in Indian population is likely to differ from the extensively studied gut flora in western population. In this study we have investigated the gut flora of two Indian families, each with three individuals belonging to successive generations and living under the same roof. Denaturation gradient gel electrophoresis analysis showed age-dependant variation in gut microflora amongst the individuals within a family. Different bacterial genera were dominant in the individual of varying age in clone library analysis. Obligate anaerobes isolated from individuals within a family showed age related differences in isolation pattern, with 27% (6 out of 22) of the isolates being potential novel species based on 16S rRNA gene sequence. In qPCR a consistent decrease in Firmicutes number and increase in Bacteroidetes number with increasing age was observed in our subjects, this pattern of change in Firmicutes / Bacteroidetes ratio with age is different than previously reported in European population. There is change in gut flora with age amongst the individuals within a family. The isolation of high percent of novel bacterial species and the pattern of change in Firmicutes /Bacteroidetes ratio with age suggests that the composition of gut flora in Indian individuals may be different than the western population. Thus, further extensive study is needed to define the gut flora in Indian population.

  10. The human footprint in the west: a large-scale analysis of anthropogenic impacts.

    USGS Publications Warehouse

    Leu, M.; Hanser, S.E.; Knick, S.T.

    2008-01-01

    Anthropogenic features such as urbanization, roads, and power lines, are increasing in western United States landscapes in response to rapidly growing human populations. However, their spatial effects have not been evaluated. Our goal was to model the human footprint across the western United States. We first delineated the actual area occupied by anthropogenic features, the physical effect area. Next, we developed the human footprint model based on the ecological effect area, the zone influenced by features beyond their physical presence, by combining seven input models: three models quantified top-down anthropogenic influences of synanthropic predators (avian predators, domestic dog and cat presence risk), and four models quantified bottom-up anthropogenic influences on habitat (invasion of exotic plants, human-caused fires, energy extraction, and anthropogenic wildland fragmentation). Using independent bird population data, we found bird abundance of four synanthropic species to correlate positively with human footprint intensity and negatively for three of the six species influenced by habitat fragmentation. We then evaluated the extent of the human footprint in relation to terrestrial (ecoregions) and aquatic systems (major rivers and lakes), regional management and conservation status, physical environment, and temporal changes in human actions. The physical effect area of anthropogenic features covered 13% of the western United States with agricultural land (9.8%) being most dominant. High-intensity human footprint areas (class 8–10) overlapped highly productive low-elevation private landholdings and covered 7% of the western United States compared to 48% for low-intensity areas (class 1–3), which were confined to low-productivity high-elevation federal landholdings. Areas within 1 km of rivers were more affected by the human footprint compared to lakes. Percentage human population growth was higher in low-intensity human footprint areas. The disproportional regional effects of the human footprint on landscapes in the western United States create a challenge to management of ecosystems and wildlife populations. Using footprint models, managers can plan land use actions, develop restoration scenarios, and identify areas of high conservation value at local landscapes within a regional context. Moreover, human footprint models serve as a tool to stratify landscapes for studies investigating floral and faunal response to human disturbance intensity gradients.

  11. Human impacts and changes in the coastal waters of south China.

    PubMed

    Wang, Linlin; Li, Qiang; Bi, Hongsheng; Mao, Xian-Zhong

    2016-08-15

    Human impact on the environment remains at the center of the debate on global environmental change. Using the Hong Kong-Shenzhen corridor in south China as an example, we present evidence that rapid urbanization and economic development in coastal areas were the dominant factors causing rapid changes in coastal waters. From 1990 to 2012, coastal seawater temperature increased ~0.060°C per year, sea level rose 4.4mm per year and pH decreased from 8.2 to 7.7, much faster than global averages. In the same period, there were exponential increases in the local population, gross domestic product and land fill area. Empirical analyses suggest that the large increase in the population affected local temperature, and economic development had a major impact on local pH. Results also show that pH and temperature were significantly correlated with local sea level rise, but pH had more predictive power, suggesting it could be considered a predictor for changes in local sea level. We conclude that human activities could significantly exacerbate local environmental changes which should be considered in predictive models and future development plans in coastal areas. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Coral Reef Ecosystems

    NASA Astrophysics Data System (ADS)

    Yap, Helen T.

    Coral reefs are geological structures of significant dimensions, constructed over millions of years by calcifying organisms. The present day reef-builders are hard corals belonging to the order Scleractinia, phylum Cnidaria. The greatest concentrations of coral reefs are in the tropics, with highest levels of biodiversity situated in reefs of the Indo-West Pacific region. These ecosystems have provided coastal protection and livelihood to human populations over the millennia. Human activities have caused destruction of these habitats, the intensity of which has increased alarmingly since the latter decades of the twentieth century. The severity of this impact is directly related to exponential growth rates of human populations especially in the coastal areas of the developing world. However, a more recently recognized phenomenon concerns disturbances brought about by the changing climate, manifested mainly as rising sea surface temperatures, and increasing acidification of ocean waters due to greater drawdown of higher concentrations of atmospheric carbon dioxide. Management efforts have so far not kept pace with the rates of degradation, so that the spatial extent of damaged reefs and the incidences of localized extinction of reef species are increasing year after year. The major management efforts to date consist of establishing marine protected areas and promoting the active restoration of coral habitats.

  13. Bouncing Back.

    ERIC Educational Resources Information Center

    Naturescope, 1987

    1987-01-01

    Presents exercises that demonstrate some of the ways humans have helped to save endangered species. Cites cases where species have been saved and populations have increased. Identifies individuals and groups that have been of assistance to endangered species. (ML)

  14. Effects of human and mosquito migrations on the dynamical behavior of the spread of malaria

    NASA Astrophysics Data System (ADS)

    Beay, Lazarus Kalvein; Kasbawati, Toaha, Syamsuddin

    2017-03-01

    Malaria is one of infectious diseases which become the main public health problem especially in Indonesia. Mathematically, the spread of malaria can be modeled to predict the outbreak of the disease. This research studies about mathematical model of the spread of malaria which takes into consideration the migration of human and mosquito populations. By determining basic reproduction number of the model, we analyze effects of migration parameter with respect to the reduction of malaria outbreak. Sensitivity analysis of basic reproduction number shows that mosquito migration has greater effect in reducing the outbreak of malaria compared with human migration. Basic reproduction number of the model is monotonically decreasing as mosquito migration increasing. We then confirm the analytic result by doing numerical simulation. The results show that migrations in human and mosquito populations have big influences in eliminating and eradicating the disease from the system.

  15. A method to identify drivers of societal change likely to affect natural assets in the future, illustrated with Australia's native biodiversity.

    PubMed

    Pepper, D A; Lada, Hania; Thomson, James R; Bakar, K Shuvo; Lake, P S; Mac Nally, Ralph

    2017-03-01

    Human society has a profound adverse effect on natural assets as human populations increase and as global climate changes. We need to envisage different futures that encompass plausible human responses to threats and change, and become more mindful of their likely impacts on natural assets. We describe a method for developing a set of future scenarios for a natural asset at national scale under ongoing human population growth and climate change. The method involves expansive consideration of potential drivers of societal change, a reduction of these to form a small set of key drivers to which contrasting settings are assigned, which we use to develop a set of different scenarios. We use Australia's native biodiversity as the focus to illustrate the method. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Environmental controls, oceanography and population dynamics of pathogens and harmful algal blooms: connecting sources to human exposure

    PubMed Central

    Dyble, Julianne; Bienfang, Paul; Dusek, Eva; Hitchcock, Gary; Holland, Fred; Laws, Ed; Lerczak, James; McGillicuddy, Dennis J; Minnett, Peter; Moore, Stephanie K; O'Kelly, Charles; Solo-Gabriele, Helena; Wang, John D

    2008-01-01

    Coupled physical-biological models are capable of linking the complex interactions between environmental factors and physical hydrodynamics to simulate the growth, toxicity and transport of infectious pathogens and harmful algal blooms (HABs). Such simulations can be used to assess and predict the impact of pathogens and HABs on human health. Given the widespread and increasing reliance of coastal communities on aquatic systems for drinking water, seafood and recreation, such predictions are critical for making informed resource management decisions. Here we identify three challenges to making this connection between pathogens/HABs and human health: predicting concentrations and toxicity; identifying the spatial and temporal scales of population and ecosystem interactions; and applying the understanding of population dynamics of pathogens/HABs to management strategies. We elaborate on the need to meet each of these challenges, describe how modeling approaches can be used and discuss strategies for moving forward in addressing these challenges. PMID:19025676

  17. Selection and explosive growth alter genetic architecture and hamper the detection of causal rare variants

    PubMed Central

    Zaitlen, Noah A.; Ye, Chun Jimmie; Witte, John S.

    2016-01-01

    The role of rare alleles in complex phenotypes has been hotly debated, but most rare variant association tests (RVATs) do not account for the evolutionary forces that affect genetic architecture. Here, we use simulation and numerical algorithms to show that explosive population growth, as experienced by human populations, can dramatically increase the impact of very rare alleles on trait variance. We then assess the ability of RVATs to detect causal loci using simulations and human RNA-seq data. Surprisingly, we find that statistical performance is worst for phenotypes in which genetic variance is due mainly to rare alleles, and explosive population growth decreases power. Although many studies have attempted to identify causal rare variants, few have reported novel associations. This has sometimes been interpreted to mean that rare variants make negligible contributions to complex trait heritability. Our work shows that RVATs are not robust to realistic human evolutionary forces, so general conclusions about the impact of rare variants on complex traits may be premature. PMID:27197206

  18. Global human mandibular variation reflects differences in agricultural and hunter-gatherer subsistence strategies

    PubMed Central

    von Cramon-Taubadel, Noreen

    2011-01-01

    Variation in the masticatory behavior of hunter-gatherer and agricultural populations is hypothesized to be one of the major forces affecting the form of the human mandible. However, this has yet to be analyzed at a global level. Here, the relationship between global mandibular shape variation and subsistence economy is tested, while controlling for the potentially confounding effects of shared population history, geography, and climate. The results demonstrate that the mandible, in contrast to the cranium, significantly reflects subsistence strategy rather than neutral genetic patterns, with hunter-gatherers having consistently longer and narrower mandibles than agriculturalists. These results support notions that a decrease in masticatory stress among agriculturalists causes the mandible to grow and develop differently. This developmental argument also explains why there is often a mismatch between the size of the lower face and the dentition, which, in turn, leads to increased prevalence of dental crowding and malocclusions in modern postindustrial populations. Therefore, these results have important implications for our understanding of human masticatory adaptation. PMID:22106280

  19. Ecology and epidemiology of Echinococcus multilocularis in Europe.

    PubMed

    Deplazes, P

    2006-06-01

    Human alveolar echinococcosis (AE), caused by the larval stage of Echinococcus multilocularis has a high mortality rate in untreated patients. The life-cycle of E. multilocularis in Europe predominantly involves foxes as definitive hosts. However, experimental studies demonstrated a comparable biotic potential of E. multilocularis in dogs and raccoon dogs but an insignificant potential in cats. AE occurs in central and eastern Europe at low incidence rates. Recent studies in foxes have shown that E. multilocularis has a wider geographic range (including Italy) than previously thought. In recent years, increases in fox populations have been observed in many European countries, especially in urban areas. As a result, the E. multilocularis cycle is now established in the urban environment. This presents an increased risk of infection for a large human population. Based on these facts and new epidemiological data, possible intervention strategies are presented.

  20. Relative influence of human harvest, carnivores, and weather on adult female elk survival across western North America

    USGS Publications Warehouse

    Brodie, Jedediah; Johnson, Heather; Mitchell, Michael; Zager, Peter; Proffitt, Kelly; Hebblewhite, Mark; Kauffman, Matthew; Johnson, Bruce; Bissonette, John; Bishop, Chad; Gude, Justin; Herbert, Jeff; Hersey, Kent R.; Hurley, Mark; Lukacs, Paul M.; McCorquodale, Scott; McIntire, Eliot; Nowak, Josh; Sawyer, Hall; Smith, Douglas; White, P.J.

    2013-01-01

    Well-informed management of harvested species requires understanding how changing ecological conditions affect demography and population dynamics, information that is lacking for many species. We have limited understanding of the relative influence of carnivores, harvest, weather and forage availability on elk Cervus elaphus demography, despite the ecological and economic importance of this species. We assessed adult female survival, a key vital rate for population dynamics, from 2746 radio-collared elk in 45 populations across western North America that experience wide variation in carnivore assemblage, harvest, weather and habitat conditions. Proportional hazard analysis revealed that 'baseline' (i.e. not related to human factors) mortality was higher with very high winter precipitation, particularly in populations sympatric with wolves Canis lupus. Mortality may increase via nutritional stress and heightened vulnerability to predation in snowy winters. Baseline mortality was unrelated to puma Puma concolor presence, forest cover or summer forage productivity. Cause-specific mortality analyses showed that wolves and all carnivore species combined had additive effects on baseline elk mortality, but only reduced survival by <2%. When human factors were included, ‘total’ adult mortality was solely related to harvest; the influence of native carnivores was compensatory. Annual total mortality rates were lowest in populations sympatric with both pumas and wolves because managers reduced female harvest in areas with abundant or diverse carnivores. Mortality from native carnivores peaked in late winter and early spring, while harvest-induced mortality peaked in autumn. The strong peak in harvest-induced mortality during the autumn hunting season decreased as the number of native carnivore species increased. Synthesis and applications. Elevated baseline adult female elk mortality from wolves in years with high winter precipitation could affect elk abundance as winters across the western US become drier and wolves recolonize portions of the region. In the absence of human harvest, wolves had additive, although limited, effects on mortality. However, human harvest, and its apparent use by managers to offset predation, primarily controls overall variation in adult female mortality. Altering harvest quotas is thus a strong tool for offsetting impacts of carnivore recolonization and shifting weather patterns on elk across western North America.

  1. Gray Wolf Exposure to Emerging Vector-Borne Diseases in Wisconsin with Comparison to Domestic Dogs and Humans

    PubMed Central

    Jara, Rocio F.; Wydeven, Adrian P.; Samuel, Michael D.

    2016-01-01

    World-wide concern over emerging vector-borne diseases has increased in recent years for both animal and human health. In the United Sates, concern about vector-borne diseases in canines has focused on Lyme disease, anaplasmosis, ehrlichiosis, and heartworm which infect domestic and wild canids. Of these diseases, Lyme and anaplasmosis are also frequently diagnosed in humans. Gray wolves (Canis lupus) recolonized Wisconsin in the 1970s, and we evaluated their temporal and geographic patterns of exposure to these four vector-borne diseases in Wisconsin as the population expanded between 1985 and 2011. A high proportion of the Wisconsin wolves were exposed to the agents that cause Lyme (65.6%) and anaplasma (47.7%), and a smaller proportion to ehrlichiosis (5.7%) and infected with heartworm (9.2%). Wolf exposure to tick borne diseases was consistently higher in older animals. Wolf exposure was markedly higher than domestic dog (Canis familiaris) exposure for all 4 disease agents during 2001–2013. We found a cluster of wolf exposure to Borrelia burgdorferi in northwestern Wisconsin, which overlaps human and domestic dog clusters for the same pathogen. In addition, wolf exposure to Lyme disease in Wisconsin has increased, corresponding with the increasing human incidence of Lyme disease in a similar time period. Despite generally high prevalence of exposure none of these diseases appear to have slowed the growth of the Wisconsin wolf population. PMID:27898670

  2. Air pollution increases forest susceptibility to wildfires: a case study for the San Bernardino Mountains in southern California

    Treesearch

    N.E. Grulke; R.A. Minnich; T. Paine; P. Riggan

    2010-01-01

    Many factors increase susceptibility of forests to wildfire. Among them are increases in human population, changes in land use, fire suppression, and frequent droughts. These factors have been exacerbating forest susceptibility to wildfires over the last century in southern California. Here we report on the significant role that air pollution has on increasing forest...

  3. Implementation of an Intersectoral Program to Eliminate Human and Canine Rabies: The Bohol Rabies Prevention and Elimination Project

    PubMed Central

    Lapiz, Stella Marie D.; Miranda, Mary Elizabeth G.; Garcia, Romulo G.; Daguro, Leonida I.; Paman, Meydalyn D.; Madrinan, Frederick P.; Rances, Polizena A.; Briggs, Deborah J.

    2012-01-01

    Background The province of Bohol, located in the Visayas islands region in the Philippines has a human population of 1.13 million and was the 4th highest region for human rabies deaths in the country, averaging 10 per year, prior to the initiation of the Bohol Rabies Prevention and Elimination Project (BRPEP). Aims The BRPEP was initiated in 2007 with the goal of building a sustainable program that would prevent human rabies by eliminating rabies at its source, in dogs, by 2010. This goal was in line with the Philippine National Rabies Program whose objective is to eliminate rabies by 2020. Methods The intersectoral BRPEP was launched in 2007 and integrated the expertise and resources from the sectors of agriculture, public health and safety, education, environment, legal affairs, interior and local government. The program included: increasing local community involvement; implementing dog population control; conducting mass dog vaccination; improving dog bite management; instituting veterinary quarantine; and improving diagnostic capability, surveillance and monitoring. Funding was secured from the national government, provincial, municipal and village units, dog owners, NGOs, the regional office of the WHO, the UBS Optimus Foundation, and the Global Alliance for Rabies Control. The BRPEP was managed by the Bohol Rabies Prevention and Eradication Council (BRPEC) under the jurisdiction of the Governor of Bohol. Parallel organizations were created at the municipal level and village level. Community volunteers facilitated the institution of the program. Dog population surveys were conducted to plan for sufficient resources to vaccinate the required 70% of the dogs living in the province. Two island-wide mass vaccination campaigns were conducted followed by “catch up” vaccination campaigns. Registration of dogs was implemented including a small fee that was rolled back into the program to maintain sustainability. Children were educated by introducing rabies prevention modules into all elementary schools in Bohol. Existing public health legislation at the national, provincial, and municipal level strengthened the enforcement of activities. A Knowledge, Attitude and Practices (KAP) survey was conducted in 2009 to evaluate the educational knowledge of the population. Increased surveillance was instituted to ensure that dogs traveling into and out of the province were vaccinated against rabies. Human and animal cases of rabies were reported to provincial and national authorities. Key Results Within the first 18 months of the BRPEP, human rabies deaths had decreased annually from 0.77 to 0.37 to zero per 100,000 population from 2007–2009. Between October 2008 and November 2010 no human and animal cases were detected. Increased surveillance on the island detected one suspected human rabies case in November 2010 and one confirmed case of canine rabies in April 2011. Two mass vaccination campaigns conducted in 2007 and 2008 successfully registered and vaccinated 44% and 70% of the dogs on the island. The additional surveillance activities enabled a mobilization of mop up vaccination activities in the region where the human and canine case was located. Due to the increased effective and continuous surveillance activities, rabies was stopped before it could spread to other areas on the island. The program costs totaled USD 450,000. Registration fees collected to maintain the program amounted to USD 105,740 and were re-allocated back into the community to sustain the program. PMID:23236525

  4. Behavioral responses of wolves to roads: scale-dependent ambivalence

    PubMed Central

    Nelson, Lindsey; Wabakken, Petter; Sand, Håkan; Liberg, Olof

    2014-01-01

    Throughout their recent recovery in several industrialized countries, large carnivores have had to cope with a changed landscape dominated by human infrastructure. Population growth depends on the ability of individuals to adapt to these changes by making use of new habitat features and at the same time to avoid increased risks of mortality associated with human infrastructure. We analyzed the summer movements of 19 GPS-collared resident wolves (Canis lupus L.) from 14 territories in Scandinavia in relation to roads. We used resource and step selection functions, including >12000 field-checked GPS-positions and 315 kill sites. Wolves displayed ambivalent responses to roads depending on the spatial scale, road type, time of day, behavioral state, and reproductive status. At the site scale (approximately 0.1 km2), they selected for roads when traveling, nearly doubling their travel speed. Breeding wolves moved the fastest. At the patch scale (10 km2), house density rather than road density was a significant negative predictor of wolf patch selection. At the home range scale (approximately 1000 km2), breeding wolves increased gravel road use with increasing road availability, although at a lower rate than expected. Wolves have adapted to use roads for ease of travel, but at the same time developed a cryptic behavior to avoid human encounters. This behavioral plasticity may have been important in allowing the successful recovery of wolf populations in industrialized countries. However, we emphasize the role of roads as a potential cause of increased human-caused mortality. PMID:25419085

  5. Behavioral responses of wolves to roads: scale-dependent ambivalence.

    PubMed

    Zimmermann, Barbara; Nelson, Lindsey; Wabakken, Petter; Sand, Håkan; Liberg, Olof

    2014-11-01

    Throughout their recent recovery in several industrialized countries, large carnivores have had to cope with a changed landscape dominated by human infrastructure. Population growth depends on the ability of individuals to adapt to these changes by making use of new habitat features and at the same time to avoid increased risks of mortality associated with human infrastructure. We analyzed the summer movements of 19 GPS-collared resident wolves ( Canis lupus L.) from 14 territories in Scandinavia in relation to roads. We used resource and step selection functions, including >12000 field-checked GPS-positions and 315 kill sites. Wolves displayed ambivalent responses to roads depending on the spatial scale, road type, time of day, behavioral state, and reproductive status. At the site scale (approximately 0.1 km 2 ), they selected for roads when traveling, nearly doubling their travel speed. Breeding wolves moved the fastest. At the patch scale (10 km 2 ), house density rather than road density was a significant negative predictor of wolf patch selection. At the home range scale (approximately 1000 km 2 ), breeding wolves increased gravel road use with increasing road availability, although at a lower rate than expected. Wolves have adapted to use roads for ease of travel, but at the same time developed a cryptic behavior to avoid human encounters. This behavioral plasticity may have been important in allowing the successful recovery of wolf populations in industrialized countries. However, we emphasize the role of roads as a potential cause of increased human-caused mortality.

  6. World-wide satellite night-light data as a proxy of society-hydrology interaction and vulnerability to flood risk

    NASA Astrophysics Data System (ADS)

    Ceola, S.; Laio, F.; Montanari, A.

    2013-12-01

    The study and the analysis of the interactions and feedbacks between hydrology and society constitute the main issue of socio-hydrology. Recent flood events, which occurred across the globe, highlighted once again that mitigation strategies are needed to reduce flood risk. In particular, quick procedures for the identification of vulnerable human settlements and flood prone areas are a necessary tool to identify priorities for flood risk management. To this aim, a 19-year long period of world-wide night light data, as a proxy of human population, and the global river network have been examined. The spatio-temporal evolution of artificial luminosity depending on the distance from the river network has been assessed in order to quantitatively identify the likelihood for a populated pixel to be reached by water. The analysis focuses both on a global and on a local scale. Hotspots, such as highly illuminated areas and developing regions, have been also examined. The analysis shows an increment of yearly-averaged artificial luminosity from 1992 to 2010 (i.e. the time period of satellite data availability), whereas light intensity tends to decrease with increasing distance from the river network. The results thus reveal an increased vulnerability of human settlements to flooding events. A nearly 70-year long period of peace and the economic development after the Second World War could reasonably explain the observed enhancement of human population proximity to water bodies.

  7. Applying bioethical principles to human biomonitoring.

    PubMed

    Harrison, Myron

    2008-06-05

    Bioethical principles are widely used as a normative framework in areas of human research and medical care. In recent years there has been increasing formalization of their use in public health decisions. The "traditional bioethical principles" are applied in this discussion to the important issue human biomonitoring for environmental exposures. They are: (1) Autonomy--Also known as the "respect for humans" principle, people understand their own best interests; (2) Beneficence--"do good" for people; (3) Nonmaleficence--"do no harm"; (4) Justice--fair distribution of benefits and costs (including risks to health) across stakeholders.Some of the points made are: (1) There is not a single generic bioethical analysis applicable to the use of human biomonitoring data, each specific use requires a separate deliberation; (2) Using unidentified, population-based biomonitoring information for risk assessment or population surveillance raises fewer bioethical concerns than personally identified biomonitoring information such as employed in health screening; (3) Companies should proactively apply normative bioethical principles when considering the disposition of products and by-products in the environment and humans; (4) There is a need for more engagement by scholars on the bioethical issues raised by the use of biomarkers of exposure; (5) Though our scientific knowledge of biology will continue to increase, there will always be a role for methods or frameworks to resolve substantive disagreements in the meaning of this data that are matters of belief rather than knowledge.

  8. Applying bioethical principles to human biomonitoring

    PubMed Central

    Harrison, Myron

    2008-01-01

    Bioethical principles are widely used as a normative framework in areas of human research and medical care. In recent years there has been increasing formalization of their use in public health decisions. The "traditional bioethical principles" are applied in this discussion to the important issue human biomonitoring for environmental exposures. They are: (1) Autonomy – Also known as the "respect for humans" principle, people understand their own best interests; (2) Beneficence – "do good" for people; (3) Nonmaleficence – "do no harm"; (4) Justice – fair distribution of benefits and costs (including risks to health) across stakeholders. Some of the points made are: (1) There is not a single generic bioethical analysis applicable to the use of human biomonitoring data, each specific use requires a separate deliberation; (2) Using unidentified, population-based biomonitoring information for risk assessment or population surveillance raises fewer bioethical concerns than personally identified biomonitoring information such as employed in health screening; (3) Companies should proactively apply normative bioethical principles when considering the disposition of products and by-products in the environment and humans; (4) There is a need for more engagement by scholars on the bioethical issues raised by the use of biomarkers of exposure; (5) Though our scientific knowledge of biology will continue to increase, there will always be a role for methods or frameworks to resolve substantive disagreements in the meaning of this data that are matters of belief rather than knowledge. PMID:18541074

  9. The Effect of Physical Activity on Student Performance in College: An Experimental Evaluation. CEPA Working Paper No. 17-03

    ERIC Educational Resources Information Center

    Fricke, Hans; Lechner, Michael; Steinmayr, Andreas

    2017-01-01

    What is the role of physical activity in the process of human capital accumulation? Brain research provides growing evidence of the importance of physical activity for various aspects of cognitive functions. An increasingly sedentary lifestyle could thus be not only harmful to population health, but also disrupt human capital accumulation. This…

  10. Learning about Coastal Trends: What Is the Story with Seagrass... and How Does It Affect Me?

    ERIC Educational Resources Information Center

    Ksiazek, Kelly; McGlathery, Karen; Reynolds, Laura; Schwarzschild, Arthur; Wilkerson, Carissa; Carruthers, Tim; Gurbisz, Cassie; Woerner, Joanna L.; Murray, Laura

    2009-01-01

    Flowering plants that live underwater in marine and estuarine habitats (seagrasses) are important because they support human food sources, such as crabs and fish, as well as endangered animals, such as turtles and manatees. Seagrasses are now known to be declining globally, largely as a result of increasing pressure from human populations living…

  11. An overview of the Southern Nevada Agency Partnership Science and Research Synthesis [Chapter 1

    Treesearch

    Jeanne C. Chambers; Matthew L. Brooks; Kent Turner; Carol B. Raish; Steven M. Ostoja

    2013-01-01

    Southern Nevada is characterized by an arid to semi-arid environment with numerous cultural resources and a high level of biological diversity. Since 1980, the human population of the region has increased at unprecedented rates largely due to the expansion of suburban areas (Hughson 2009). The various human activities associated with this growth and the interactions of...

  12. A national approach for integrating wildfire simulation modeling into Wildland Urban Interface risk assessments within the United States

    Treesearch

    Jessica R. Haas; David E. Calkin; Matthew P. Thompson

    2013-01-01

    Ongoing human development into fire-prone areas contributes to increasing wildfire risk to human life. It is critically important, therefore, to have the ability to characterize wildfire risk to populated places, and to identify geographic areas with relatively high risk. A fundamental component of wildfire risk analysis is establishing the likelihood of wildfire...

  13. Perfluorooctanoic acid (PFOA), an emerging drinking water contaminant: a critical review of recent literature.

    PubMed

    Post, Gloria B; Cohn, Perry D; Cooper, Keith R

    2012-07-01

    Perfluorooctanoic acid (PFOA) is an anthropogenic contaminant that differs in several ways from most other well-studied organic chemicals found in drinking water. PFOA is extremely resistant to environmental degradation processes and thus persists indefinitely. Unlike most other persistent and bioaccumulative organic pollutants, PFOA is water-soluble, does not bind well to soil or sediments, and bioaccumulates in serum rather than in fat. It has been detected in finished drinking water and drinking water sources impacted by releases from industrial facilities and waste water treatment plants, as well as in waters with no known point sources. However, the overall occurrence and population exposure from drinking water is not known. PFOA persists in humans with a half-life of several years and is found in the serum of almost all U.S. residents and in populations worldwide. Exposure sources include food, food packaging, consumer products, house dust, and drinking water. Continued exposure to even relatively low concentrations in drinking water can substantially increase total human exposure, with a serum:drinking water ratio of about 100:1. For example, ongoing exposures to drinking water concentrations of 10 ng/L, 40 ng/L, 100 ng/L, or 400 ng/L are expected to increase mean serum levels by about 25%, 100%, 250%, and 1000%, respectively, from the general population background serum level of about 4 ng/mL. Infants are potentially a sensitive subpopulation for PFOA's developmental effects, and their exposure through breast milk from mothers who use contaminated drinking water and/or from formula prepared with contaminated drinking water is higher than in adults exposed to the same drinking water concentration. Numerous health endpoints are associated with human PFOA exposure in the general population, communities with contaminated drinking water, and workers. As is the case for most such epidemiology studies, causality for these effects is not proven. Unlike most other well-studied drinking water contaminants, the human dose-response curve for several effects appears to be steepest at the lower exposure levels, including the general population range, with no apparent threshold for some endpoints. There is concordance in animals and humans for some effects, while humans and animals appear to react differently for other effects such as lipid metabolism. PFOA was classified as "likely to be carcinogenic in humans" by the USEPA Science Advisory Board. In animal studies, developmental effects have been identified as more sensitive endpoints for toxicity than carcinogenicity or the long-established hepatic effects. Notably, exposure to an environmentally relevant drinking water concentration caused adverse effects on mammary gland development in mice. This paper reviews current information relevant to the assessment of PFOA as an emerging drinking water contaminant. This information suggests that continued human exposure to even relatively low concentrations of PFOA in drinking water results in elevated body burdens that may increase the risk of health effects. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Relating Land Use and Human Intra-City Mobility

    PubMed Central

    Lee, Minjin; Holme, Petter

    2015-01-01

    Understanding human mobility patterns—how people move in their everyday lives—is an interdisciplinary research field. It is a question with roots back to the 19th century that has been dramatically revitalized with the recent increase in data availability. Models of human mobility often take the population distribution as a starting point. Another, sometimes more accurate, data source is land-use maps. In this paper, we discuss how the intra-city movement patterns, and consequently population distribution, can be predicted from such data sources. As a link between land use and mobility, we show that the purposes of people’s trips are strongly correlated with the land use of the trip’s origin and destination. We calibrate, validate and discuss our model using survey data. PMID:26445147

  15. AIDS, Avian flu, SARS, MERS, Ebola, Zika… what next?

    PubMed

    Reperant, Leslie A; Osterhaus, Albert D M E

    2017-08-16

    Emerging infections have threatened humanity since times immemorial. The dramatic anthropogenic, behavioral and social changes that have affected humanity and the environment in the past century have accelerated the intrusion of novel pathogens into the global human population, sometimes with devastating consequences. The AIDS and influenza pandemics have claimed and will continue to claim millions of lives. The recent SARS and Ebola epidemics have threatened populations across borders. The emergence of MERS may well be warning signals of a nascent pandemic threat, while the potential for geographical spread of vector-borne diseases, such as Zika, but also Dengue and Chikungunya is unprecedented. Novel technologies and innovative approaches have multiplied to address and improve response preparedness towards the increasing yet unpredictable threat posed by emerging pathogens. Copyright © 2017. Published by Elsevier Ltd.

  16. Immunization of HIV-infected adult patients — French recommendations

    PubMed Central

    Frésard, Anne; Gagneux-Brunon, Amandine; Lucht, Frédéric; Botelho-Nevers, Elisabeth; Launay, Odile

    2016-01-01

    ABSTRACT Human immunodeficiency virus (HIV)-infected patients remain at increased risk of infection including vaccine-preventable diseases. Vaccines are therefore critical components in the protection of HIV-infected patients from an increasing number of preventable diseases. However, missed opportunities for vaccination among HIV-infected patients persist and vaccine coverage in this population could be improved. This article presents the French recommendations regarding immunization of HIV-infected adults in the light of the evidence-based literature on the benefits and the potential risks of vaccines among this vulnerable population. PMID:27409293

  17. Impact of effects of acid precipitation on toxicity of metals.

    PubMed Central

    Nordberg, G F; Goyer, R A; Clarkson, T W

    1985-01-01

    Acid precipitation may increase human exposure to several potentially toxic metals by increasing metal concentrations in major pathways to man, particularly food and water, and in some instances by enhancing the conversion of metal species to more toxic forms. Human exposures to methylmercury are almost entirely by way of consumption of fish and seafood. In some countries, intakes by this route may approach the levels that can give rise to adverse health effects for population groups with a high consumption of these food items. A possible increase in methylmercury concentrations in fish from lakes affected by acid precipitation may thus be of concern to selected population groups. Human exposures to lead reach levels that are near those associated with adverse health effects in certain sensitive segments of the general population in several countries. The possibility exists that increased exposures to lead may be caused by acid precipitation through a mobilization of lead from soils into crops. A route of exposure to lead that may possibly be influenced by acid precipitation is an increased deterioration of surface materials containing lead and a subsequent ingestion by small children. A similar situation with regard to uptake from food exists for cadmium (at least in some countries). Human metal exposures via drinking water may be increased by acid precipitation. Decreasing pH increases corrosiveness of water enhancing the mobilization of metal salts from soil; metallic compounds may be mobilized from minerals, which may eventually reach drinking water. Also, the dissolution of metals (Pb, Cd, Cu) from piping systems for drinking water by soft acidic waters of high corrosivity may increase metal concentrations in drinking water. Exposures have occasionally reached concentrations which are in the range where adverse health effects may be expected in otherwise healthy persons. Dissolution from piping systems can be prevented by neutralizing the water before distribution. Increased aluminum concentrations in water is a result mainly of the occurrence of Al in acidified natural waters and the use of Al chemicals in drinking water purification. If such water is used for dialysis in patients with chronic renal failure, it may give rise to cases of dialysis dementia and other disorders. A possible influence on health of persons with normal renal function (e.g., causing Alzheimer's disease) is uncertain and requires further investigation.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:3908087

  18. Tracing the peopling of the world through genomics

    PubMed Central

    Nielsen, Rasmus; Akey, Joshua M.; Jakobsson, Mattias; Pritchard, Jonathan K.; Tishkoff, Sarah; Willerslev, Eske

    2018-01-01

    Advances in the sequencing and the analysis of the genomes of both modern and ancient peoples have facilitated a number of breakthroughs in our understanding of human evolutionary history. These include the discovery of interbreeding between anatomically modern humans and extinct hominins; the development of an increasingly detailed description of the complex dispersal of modern humans out of Africa and their population expansion worldwide; and the characterization of many of the genetic adaptions of humans to local environmental conditions. Our interpretation of the evolutionary history and adaptation of humans is being transformed by analyses of these new genomic data. PMID:28102248

  19. Inferring Admixture Histories of Human Populations Using Linkage Disequilibrium

    PubMed Central

    Loh, Po-Ru; Lipson, Mark; Patterson, Nick; Moorjani, Priya; Pickrell, Joseph K.; Reich, David; Berger, Bonnie

    2013-01-01

    Long-range migrations and the resulting admixtures between populations have been important forces shaping human genetic diversity. Most existing methods for detecting and reconstructing historical admixture events are based on allele frequency divergences or patterns of ancestry segments in chromosomes of admixed individuals. An emerging new approach harnesses the exponential decay of admixture-induced linkage disequilibrium (LD) as a function of genetic distance. Here, we comprehensively develop LD-based inference into a versatile tool for investigating admixture. We present a new weighted LD statistic that can be used to infer mixture proportions as well as dates with fewer constraints on reference populations than previous methods. We define an LD-based three-population test for admixture and identify scenarios in which it can detect admixture events that previous formal tests cannot. We further show that we can uncover phylogenetic relationships among populations by comparing weighted LD curves obtained using a suite of references. Finally, we describe several improvements to the computation and fitting of weighted LD curves that greatly increase the robustness and speed of the calculations. We implement all of these advances in a software package, ALDER, which we validate in simulations and apply to test for admixture among all populations from the Human Genome Diversity Project (HGDP), highlighting insights into the admixture history of Central African Pygmies, Sardinians, and Japanese. PMID:23410830

  20. [Genetic ecological monitoring in human populations: heterozygosity, mtDNA haplotype variation, and genetic load].

    PubMed

    Balanovskiĭ, O P; Koshel', S M; Zaporozhchenko, V V; Pshenichnov, A S; Frolova, S A; Kuznetsova, M A; Baranova, E E; Teuchezh, I E; Kuznetsova, A A; Romashkina, M V; Utevskaia, O M; Churnosov, M I; Villems, R; Balanovskaia, E V

    2011-11-01

    Yu. P. Altukhov suggested that heterozygosity is an indicator of the state of the gene pool. The idea and a linked concept of genetic ecological monitoring were applied to a new dataset on mtDNA variation in East European ethnic groups. Haplotype diversity (an analog of the average heterozygosity) was shown to gradually decrease northwards. Since a similar trend is known for population density, interlinked changes were assumed for a set of parameters, which were ordered to form a causative chain: latitude increases, land productivity decreases, population density decreases, effective population size decreases, isolation of subpopulations increases, genetic drift increases, and mtDNA haplotype diversity decreases. An increase in genetic drift increases the random inbreeding rate and, consequently, the genetic load. This was confirmed by a significant correlation observed between the incidence of autosomal recessive hereditary diseases and mtDNA haplotype diversity. Based on the findings, mtDNA was assumed to provide an informative genetic system for genetic ecological monitoring; e.g., analyzing the ecology-driven changes in the gene pool.

  1. Experimental design and quantitative analysis of microbial community multiomics.

    PubMed

    Mallick, Himel; Ma, Siyuan; Franzosa, Eric A; Vatanen, Tommi; Morgan, Xochitl C; Huttenhower, Curtis

    2017-11-30

    Studies of the microbiome have become increasingly sophisticated, and multiple sequence-based, molecular methods as well as culture-based methods exist for population-scale microbiome profiles. To link the resulting host and microbial data types to human health, several experimental design considerations, data analysis challenges, and statistical epidemiological approaches must be addressed. Here, we survey current best practices for experimental design in microbiome molecular epidemiology, including technologies for generating, analyzing, and integrating microbiome multiomics data. We highlight studies that have identified molecular bioactives that influence human health, and we suggest steps for scaling translational microbiome research to high-throughput target discovery across large populations.

  2. Ecological resource management: A call to arms

    USGS Publications Warehouse

    Emlen, J.M.; Kapustka, Lawrence; Barnthouse, L.; Beyer, N.; Biddinger, G.; Kedwards, T.; Landis, W.; Menzie, C.; Munns, W.; Sorenson, M.; Wentsel, R.

    2002-01-01

    As the human population enlarges, it becomes increasingly difficult to sustain valued ecological resources. Human use of resources, whether it is the harvest of ocean fisheries, logging of forests, or farming of arable lands, has resulted in significant population declines in many wildlife species. The growth of urban areas and the expansion of impermeable surfaces alter landscape diversity and modify hydrologic patterns in ways that decrease habitat quality for many desired plant, fish, and wildlife species. Impaired water, air, and soil quality related to industrial, municipal, and agricultural activities have altered the composition of aquatic and terrestrial communities.

  3. Decline of recent seabirds inferred from a composite 1000-year record of population dynamics

    PubMed Central

    Xu, Liqiang; Liu, Xiaodong; Wu, Libin; Sun, Liguang; Zhao, Jinjun; Chen, Lin

    2016-01-01

    Based on three ornithogenic sediment profiles and seabird subfossils therein from the Xisha Islands, South China Sea, the relative population size of seabirds over the past 1000 years was reconstructed using reflectance spectrum. Here we present an apparent increase and subsequent decline of seabirds on these islands in the South China Sea. Seabird populations peaked during the Little Ice Age (LIA, 1400–1850 AD), implying that the cool climate during the LIA appears to have been more favorable to seabirds on the Xisha Islands in the South China Sea. Climate change partly explains the recent decrease in seabird populations over the past 150 years, but the significant decline and almost complete disappearance thereof on most of the Xisha Islands is probably attributable to human disturbance. Our study reveals the increasing impact of anthropogenic activities on seabird population in recent times. PMID:27748366

  4. Newly rare or newly common: evolutionary feedbacks through changes in population density and relative species abundance, and their management implications

    PubMed Central

    Lankau, Richard A; Strauss, Sharon Y

    2011-01-01

    Environmental management typically seeks to increase or maintain the population sizes of desirable species and to decrease population sizes of undesirable pests, pathogens, or invaders. With changes in population size come long-recognized changes in ecological processes that act in a density-dependent fashion. While the ecological effects of density dependence have been well studied, the evolutionary effects of changes in population size, via changes in ecological interactions with community members, are underappreciated. Here, we provide examples of changing selective pressures on, or evolution in, species as a result of changes in either density of conspecifics or changes in the frequency of heterospecific versus conspecific interactions. We also discuss the management implications of such evolutionary responses in species that have experienced rapid increases or decreases in density caused by human actions. PMID:25567977

  5. Research Note:Effects of human activities on the Yangtze River suspended sediment flux into the estuary in the last century

    NASA Astrophysics Data System (ADS)

    Yang, S. L.; Shi, Z.; Zhao, H. Y.; Li, P.; Dai, S. B.; Gao, A.

    The surface erosion area in the Yangtze River basin increased from 364×103 km2 in the 1950s to 707×103 km2 in 2001 due to a great increase in population. Based on the regression relationship between surface erosion area and population, the surface erosion area was predicted to be about 280×103 km2 at the beginning of the 20th century. The sediment yield, which increased by about 30% during the first six decades of the 20th century, was closely related to the surface erosion area in this river basin. The Yangtze annual suspended sediment flux into the estuary was about 395×106 t a-1 at the beginning of the century, and this gradually increased to an average of 509×106 t a-1 in the 1960s. The increase in the suspended sediment flux into the estuary was accelerated in the 1950s and the 1960s due to the rapid increase in population and land use immediately after the Second World War and the Liberation War. After the riverine suspended sediment flux reached its maximum in the 1960s, it decreased to <206×106 t a-1 in 2003. Construction of dams was found to be the principal cause for this decreasing trend because, during the same period, (a) the riverine water discharge did not show a decreasing trend, (b) water diversion was not influential and (c) sedimentation in lakes and canals of the middle and lower reaches did not increase. The total storage capacity of reservoirs has increased dramatically over the past half century. The amount of sediment trapped in reservoirs has increased to more than half a billion t a-1. As a result, the suspended sediment flux into the estuary dramatically decreased, even though the sediment yield from many areas of the basin increased in recent decades. Human activities gradually increased the suspended sediment flux into the estuary before the 1960s and then rapidly decreased it. The last century was a period when the Yangtze suspended sediment flux into the estuary was dramatically affected by human activities.

  6. Understanding population and individual risk assessment: the case of polychlorinated biphenyls.

    PubMed

    Shields, Peter G

    2006-05-01

    Decisions about how to improve or protect the public health can be, and sometimes necessarily are, made on imprecise science. The regulation of potential human carcinogens in the environment entails a population-risk assessment process intended to reduce risks to less than one additional cancer in 100,000 or 1,000,000 persons. These risk assessment processes, however, may be miscommunicated or misinterpreted in the context of individual cancer risks by scientists, regulators, the lay media, and the public. This commentary will review methods for establishing a causal relationship between carcinogen exposures and cancer risk. It will use the case of polychlorinated biphenyls (PCB) as an example of how to place scientific data into the context of human exposure and cancer risk. PCBs are widespread environmental contaminants and most people have detectable levels of PCBs in their bodies. The primary source for exposure in the general population is through the diet. PCBs are carcinogens in experimental animal models, but how this information can be extrapolated to human risk remains uncertain. PCB experimental studies provide data that are used to regulate and control human exposure, although the epidemiologic evidence fails to establish PCBs as human carcinogens. Thus, what is used for population-risk assessment may not be appropriate for individual-risk assessment or concluding that a causal relationship exists between PCB exposure and cancer risk. The hazards from a carcinogen designated by regulatory and review agencies as a "probable" human carcinogen is often misunderstood out of context about the magnitude of the risk and in what settings. How scientists communicate their results in scientific articles can strongly influence how others interpret their data. Misunderstandings from both the use of regulatory and review-agency opinions and the conclusions espoused by scientists occur in the media, among private physicians counseling their patients about cancer risk, and in the legal settings where plaintiffs seek compensation for exposure and alleged harm (or future harm). This can lead to false conclusions about what caused a cancer in a specific patient, undue anxiety about future cancer risk, inappropriate cancer screening, and attendant increased morbidity due to increased uses of the medical system and complication rates from medical procedures. The communication of research findings by scientists must be presented with caution, resisting the temptation to extrapolate, inappropriately, research data to the general population.

  7. Urbanization in the US: land use trends, impacts on forest area, projections, and policy considerations

    Treesearch

    Ralph Alig

    2010-01-01

    Since World War II, socio-economic drivers of US urbanization such as population totals and personal income levels have increased substantially. Human land use is the primary force driving changes in forest ecosystem attributes including forest area, which is the focus of this paper. The percentage of the US population residing in urban areas is higher than that in...

  8. Wildlife and pastoral society--shifting paradigms in disease control.

    PubMed

    Kock, Richard; Kebkiba, Bidjeh; Heinonen, Risto; Bedane, Berhanu

    2002-10-01

    The dramatic changes in the human and animal populations in Africa over the last century demand the re-examination of priorities and policies. The introduction of developed medical and other human technologies into the continent has contributed to increases in population and a rapid, unsustainable increase in the utilization of resources. This in turn has led to the destruction of flora and fauna on an unprecedented scale with little real improvement in the human condition. One factor in this has been the increase in livestock in line with human demographic growth, as it is a traditional livelihood of many African peoples. In recent years the growth in livestock populations has slowed owing to a cycle of degradation and disease, affecting especially traditional pastoral systems with a close physical association between people, livestock, and wild animals. Pathogens benefit hugely from the dynamic state created by animal migration, although to some extent the livestock and certainly wildlife show considerable tolerance to this. One of the grave economic consequences of this increase in disease has been collapse of the export trade. In order for Africa to fully benefit and share in world trade, the zoosanitary situation must show improvement. To do this without destroying the natural resource base and traditional pastoral systems, will require a careful, future-oriented land-use policy along ecologically sound criteria. Export livestock will have to be maintained in areas, probably free of ruminant wildlife, with strict veterinary controls. If this can be balanced with sufficient areas retained for traditional pastoralism and wildlife, with perhaps the main income from recreational tourism and local consumption, the benefits will be considerable. The answer may be community-based, low-cost, decentralized health systems for pastoral communities, with less stringent sanitary mandates, a private/parastatal sector servicing, with specialization in wildlife, dairy or export livestock and a central veterinary policy, related to surveillance and monitoring using small well-resourced professional teams to carry out regulatory and statutory duties.

  9. Environmental and Ecological Effects of Climate Change on Venomous Marine and Amphibious Species in the Wilderness.

    PubMed

    Needleman, Robert K; Neylan, Isabelle P; Erickson, Timothy B

    2018-06-25

    Recent analyses of data show a warming trend in global average air and sea surface ocean temperatures. The atmosphere and ocean have warmed, the amounts of snow and ice have diminished, the sea level has risen, and the concentrations of greenhouse gases have increased. This article will focus on climate change and projected effects on venomous marine and amphibious creatures with the potential impact on human health. Retrospective analysis of environmental, ecological, and medical literature with a focus on climate change, toxinology, and future modeling specific to venomous aquatic and amphibious creatures. Species included venomous jellyfish, poisonous fish, crown-of-thorns starfish, sea snakes, and toxic frogs. In several projected scenarios, rising temperatures, weather extremes, and shifts in seasons will increase poisonous population numbers, particularly with certain marine creatures like jellyfish and crown-of-thorns starfish. Habitat expansions by lionfish and sea snakes are projected to occur. These phenomena, along with increases in human populations and coastal development will likely increase human-animal encounters. Other species, particularly amphibious toxic frogs, are declining rapidly due to their sensitivity to any temperature change or subtle alterations in the stability of their environment. If temperatures continue to rise to record levels over the next decades, it is predicted that the populations of these once plentiful and critically important animals to the aquatic ecosystem will decline and their geographic distributions will shrink. Review of the literature investigating the effect and forecasts of climate change on venomous marine and amphibious creatures has demonstrated that temperature extremes and changes to climatic norms will likely have a dramatic effect on these toxicological organisms. The effects of climate change on these species through temperature alteration and rising coastal waters will influence each species differently and in turn potentially affect commercial industries, travel, tourism, and human health. Published by Elsevier Inc.

  10. People, poverty and the Earth Summit.

    PubMed

    Wheeler, J

    1992-01-01

    UNCED is about human beings managing their affairs so that all can achieve a reasonably good life without destroying the life-supporting environment. Currently human activities are approaching an upset of environmental balance through production of greenhouse gases, depletion of the ozone layer, and reduction of natural resources. Equity is the right to a decent life for the current human population of 5.5 billion and the future 10 billion expected within the next 50 years. A minimum use of environmental space/person is required. The Earth Summit will be a broad statement of environmental policy. Agenda 21 includes 115 action programs within 40 chapters. Separate conventions will be held on climate and biodiversity. The secretariat of UNCED has been working primarily with Agenda 21. Population issues are emphasized in Chapter 5 ("Demographic Dynamics and Sustainability") of the first section in Agenda 21 on Social and Economic Dimensions. The program areas include 1) research on the links between population, the environment, and development; 2) formulation by governments of integrated national policies on environment and development, which account for demographic trends, and promotion of population literacy; and 3) implementation of local level programs to ensure access to education and information and services in order to plan families freely and responsibly. Increases in funding for the population program are anticipated to be US $9 billion by the year 2000 and about US $7 billion/year until then. The year 2000 will bring with it a doubling of urban population in developing countries. There are challenges and opportunities to expand private sector job creation, education, clean water, and family health services. In addition to managing human settlements, there is also management of fragile ecosystems, which means relieving the pressure on these lands through urban migration or relocation to richer agricultural areas. The goal for agriculture is to triple food outputs over the next 50 years without increasing land use; improved soil and management systems are needed. Ocean/seas protection from pollution and provision of an adequate, clean water supply are other challenges. Demographic transition must be completed in order to improve global development success.

  11. Land use change and population growth in the Morobe Province of Papua New Guinea between 1975 and 2000.

    PubMed

    Ningal, Tine; Hartemink, A E; Bregt, A K

    2008-04-01

    The relation between human population growth and land use change is much debated. Here we present a case study from Papua New Guinea where the population has increased from 2.3 million in 1975 to 5.2 million in 2000. Since 85% of the population relies on subsistence agriculture, population growth affects agricultural land use. We assessed land use change in the Morobe province (33,933 km2) using topographic maps of 1975 and Landsat TM images of 1990 and 2000. Between 1975 and 2000, agricultural land use increased by 58% and population grew by 99%. Most new agricultural land was taken from primary forest and the forest area decreased from 9.8 ha person(-1) in 1975 to 4.4 ha person(-1) in 2000. Total population change and total land use change were strongly correlated. Most of the agricultural land use change occurred on Inceptisols in areas with high rainfall (>2500 mm year(-1)) on moderate to very steep slopes (10-56%). Agricultural land use changes in logged-over areas were in the vicinity of populated places (villages), and in close proximity to road access. There was considerable variation between the districts but districts with higher population growth also had larger increases in agricultural areas. It is concluded that in the absence of improved farming systems the current trend of increased agriculture with rapid population growth is likely to continue.

  12. Global use of alcohol, drugs and tobacco.

    PubMed

    Anderson, Peter

    2006-11-01

    Humans have always used drugs, probably as part of their evolutionary and nutritional heritage. However, this previous biological adaptation is unlikely to be so in the modern world, in which 2 billion adults (48% of the adult population) are current users of alcohol, 1.1 billion adults (29% of the adult population) are current smokers of cigarettes and 185 million adults (4.5% of the adult population) are current users of illicit drugs. The use of drugs is determined largely by market forces, with increases in affordability and availability increasing use. People with socio-economic deprivation, however measured, are at increased risk of harmful drug use, as are those with a disadvantaged family environment, and those who live in a community with higher levels of substance use. Substance use is on the increase in low-income countries which, in the coming decades, will bear a disproportionate burden of substance-related disability and premature death.

  13. A demographic transition altered the strength of selection for fitness and age-specific survival and fertility in a 19th century American population

    PubMed Central

    Moorad, Jacob A.

    2012-01-01

    Modernization has increased longevity and decreased fertility in many human populations, but it is not well understood how or to what extent these demographic transitions have altered patterns of natural selection. I integrate individual-based multivariate phenotypic selection approaches with evolutionary demographic methods to demonstrate how a demographic transition in 19th century female populations of Utah altered relationships between fitness and age-specific survival and fertility. Coincident with this demographic transition, natural selection for fitness, as measured by the opportunity for selection, increased by 13–20% over 65 years. Proportional contributions of age-specific survival to total selection (the complement to age-specific fertility) diminished from approximately 1/3 to 1/7 following a marked increase in infant survival. Despite dramatic reductions in age-specific fertility variance at all ages, the absolute magnitude of selection for fitness explained by age-specific fertility increased by approximately 45%. I show that increases in the adaptive potential of fertility traits followed directly from decreased population growth rates. These results suggest that this demographic transition has increased the adaptive potential of the Utah population, intensified selection on reproductive traits, and de-emphasized selection on survival-related traits. PMID:23730757

  14. Comparing population structure as inferred from genealogical versus genetic information.

    PubMed

    Colonna, Vincenza; Nutile, Teresa; Ferrucci, Ronald R; Fardella, Giulio; Aversano, Mario; Barbujani, Guido; Ciullo, Marina

    2009-12-01

    Algorithms for inferring population structure from genetic data (ie, population assignment methods) have shown to effectively recognize genetic clusters in human populations. However, their performance in identifying groups of genealogically related individuals, especially in scanty-differentiated populations, has not been tested empirically thus far. For this study, we had access to both genealogical and genetic data from two closely related, isolated villages in southern Italy. We found that nearly all living individuals were included in a single pedigree, with multiple inbreeding loops. Despite F(st) between villages being a low 0.008, genetic clustering analysis identified two clusters roughly corresponding to the two villages. Average kinship between individuals (estimated from genealogies) increased at increasing values of group membership (estimated from the genetic data), showing that the observed genetic clusters represent individuals who are more closely related to each other than to random members of the population. Further, average kinship within clusters and F(st) between clusters increases with increasingly stringent membership threshold requirements. We conclude that a limited number of genetic markers is sufficient to detect structuring, and that the results of genetic analyses faithfully mirror the structuring inferred from detailed analyses of population genealogies, even when F(st) values are low, as in the case of the two villages. We then estimate the impact of observed levels of population structure on association studies using simulated data.

  15. Comparing population structure as inferred from genealogical versus genetic information

    PubMed Central

    Colonna, Vincenza; Nutile, Teresa; Ferrucci, Ronald R; Fardella, Giulio; Aversano, Mario; Barbujani, Guido; Ciullo, Marina

    2009-01-01

    Algorithms for inferring population structure from genetic data (ie, population assignment methods) have shown to effectively recognize genetic clusters in human populations. However, their performance in identifying groups of genealogically related individuals, especially in scanty-differentiated populations, has not been tested empirically thus far. For this study, we had access to both genealogical and genetic data from two closely related, isolated villages in southern Italy. We found that nearly all living individuals were included in a single pedigree, with multiple inbreeding loops. Despite Fst between villages being a low 0.008, genetic clustering analysis identified two clusters roughly corresponding to the two villages. Average kinship between individuals (estimated from genealogies) increased at increasing values of group membership (estimated from the genetic data), showing that the observed genetic clusters represent individuals who are more closely related to each other than to random members of the population. Further, average kinship within clusters and Fst between clusters increases with increasingly stringent membership threshold requirements. We conclude that a limited number of genetic markers is sufficient to detect structuring, and that the results of genetic analyses faithfully mirror the structuring inferred from detailed analyses of population genealogies, even when Fst values are low, as in the case of the two villages. We then estimate the impact of observed levels of population structure on association studies using simulated data. PMID:19550436

  16. Effects of household dynamics on resource consumption and biodiversity.

    PubMed

    Liu, Jianguo; Daily, Gretchen C; Ehrlich, Paul R; Luck, Gary W

    2003-01-30

    Human population size and growth rate are often considered important drivers of biodiversity loss, whereas household dynamics are usually neglected. Aggregate demographic statistics may mask substantial changes in the size and number of households, and their effects on biodiversity. Household dynamics influence per capita consumption and thus biodiversity through, for example, consumption of wood for fuel, habitat alteration for home building and associated activities, and greenhouse gas emissions. Here we report that growth in household numbers globally, and particularly in countries with biodiversity hotspots (areas rich in endemic species and threatened by human activities), was more rapid than aggregate population growth between 1985 and 2000. Even when population size declined, the number of households increased substantially. Had the average household size (that is, the number of occupants) remained static, there would have been 155 million fewer households in hotspot countries in 2000. Reduction in average household size alone will add a projected 233 million additional households to hotspot countries during the period 2000-15. Rapid increase in household numbers, often manifested as urban sprawl, and resultant higher per capita resource consumption in smaller households pose serious challenges to biodiversity conservation.

  17. An historical perspective on eutrophication in the Pensacola ...

    EPA Pesticide Factsheets

    In this chapter, we provide a brief description of the Pensacola Bay estuary, examining the available historical data for evidence of trends in eutrophication within the estuary. Common to many industrialized estuaries, Pensacola Bay has been subjected to unregulated point sources of nutrients and other contaminants, peaking during the 1950s and 1960s. Also, over the past 60 years, the region has experienced a 5-fold increase in population in the watershed and a doubling of river nitrate concentrations. Today, the estuary exhibits classical symptoms of eutrophication, including extensive summer hypoxia, significant loss of seagrass habitat, and phytoplankton dynamics that respond strongly to seasonal and interannual variation in freshwater flow. Surprisingly, Pensacola Bay appears to have low nutrient concentrations, moderate productivity, and high water transparency; characteristics that appear to have persisted during a period of rapid human population growth. We find the lack of demonstrable changes in the distribution of phytoplankton biomass or distribution and severity of hypoxia during a period of increasing human population pressures enigmatic. This brief manuscript summarizes historical water quality data from Pensacola Bay Florida

  18. Economic development and coastal ecosystem change in China.

    PubMed

    He, Qiang; Bertness, Mark D; Bruno, John F; Li, Bo; Chen, Guoqian; Coverdale, Tyler C; Altieri, Andrew H; Bai, Junhong; Sun, Tao; Pennings, Steven C; Liu, Jianguo; Ehrlich, Paul R; Cui, Baoshan

    2014-08-08

    Despite their value, coastal ecosystems are globally threatened by anthropogenic impacts, yet how these impacts are driven by economic development is not well understood. We compiled a multifaceted dataset to quantify coastal trends and examine the role of economic growth in China's coastal degradation since the 1950s. Although China's coastal population growth did not change following the 1978 economic reforms, its coastal economy increased by orders of magnitude. All 15 coastal human impacts examined increased over time, especially after the reforms. Econometric analysis revealed positive relationships between most impacts and GDP across temporal and spatial scales, often lacking dropping thresholds. These relationships generally held when influences of population growth were addressed by analyzing per capita impacts, and when population density was included as explanatory variables. Historical trends in physical and biotic indicators showed that China's coastal ecosystems changed little or slowly between the 1950s and 1978, but have degraded at accelerated rates since 1978. Thus economic growth has been the cause of accelerating human damage to China's coastal ecosystems. China's GDP per capita remains very low. Without strict conservation efforts, continuing economic growth will further degrade China's coastal ecosystems.

  19. Genetic and environmental influences on adult human height across birth cohorts from 1886 to 1994

    PubMed Central

    Jelenkovic, Aline; Hur, Yoon-Mi; Sund, Reijo; Yokoyama, Yoshie; Siribaddana, Sisira H; Hotopf, Matthew; Sumathipala, Athula; Rijsdijk, Fruhling; Tan, Qihua; Zhang, Dongfeng; Pang, Zengchang; Aaltonen, Sari; Heikkilä, Kauko; Öncel, Sevgi Y; Aliev, Fazil; Rebato, Esther; Tarnoki, Adam D; Tarnoki, David L; Christensen, Kaare; Skytthe, Axel; Kyvik, Kirsten O; Silberg, Judy L; Eaves, Lindon J; Maes, Hermine H; Cutler, Tessa L; Hopper, John L; Ordoñana, Juan R; Sánchez-Romera, Juan F; Colodro-Conde, Lucia; Cozen, Wendy; Hwang, Amie E; Mack, Thomas M; Sung, Joohon; Song, Yun-Mi; Yang, Sarah; Lee, Kayoung; Franz, Carol E; Kremen, William S; Lyons, Michael J; Busjahn, Andreas; Nelson, Tracy L; Whitfield, Keith E; Kandler, Christian; Jang, Kerry L; Gatz, Margaret; Butler, David A; Stazi, Maria A; Fagnani, Corrado; D'Ippolito, Cristina; Duncan, Glen E; Buchwald, Dedra; Derom, Catherine A; Vlietinck, Robert F; Loos, Ruth JF; Martin, Nicholas G; Medland, Sarah E; Montgomery, Grant W; Jeong, Hoe-Uk; Swan, Gary E; Krasnow, Ruth; Magnusson, Patrik KE; Pedersen, Nancy L; Dahl-Aslan, Anna K; McAdams, Tom A; Eley, Thalia C; Gregory, Alice M; Tynelius, Per; Baker, Laura A; Tuvblad, Catherine; Bayasgalan, Gombojav; Narandalai, Danshiitsoodol; Lichtenstein, Paul; Spector, Timothy D; Mangino, Massimo; Lachance, Genevieve; Bartels, Meike; van Beijsterveldt, Toos CEM; Willemsen, Gonneke; Burt, S Alexandra; Klump, Kelly L; Harris, Jennifer R; Brandt, Ingunn; Nilsen, Thomas Sevenius; Krueger, Robert F; McGue, Matt; Pahlen, Shandell; Corley, Robin P; Hjelmborg, Jacob v B; Goldberg, Jack H; Iwatani, Yoshinori; Watanabe, Mikio; Honda, Chika; Inui, Fujio; Rasmussen, Finn; Huibregtse, Brooke M; Boomsma, Dorret I; Sørensen, Thorkild I A; Kaprio, Jaakko; Silventoinen, Karri

    2016-01-01

    Human height variation is determined by genetic and environmental factors, but it remains unclear whether their influences differ across birth-year cohorts. We conducted an individual-based pooled analysis of 40 twin cohorts including 143,390 complete twin pairs born 1886–1994. Although genetic variance showed a generally increasing trend across the birth-year cohorts, heritability estimates (0.69-0.84 in men and 0.53-0.78 in women) did not present any clear pattern of secular changes. Comparing geographic-cultural regions (Europe, North America and Australia, and East Asia), total height variance was greatest in North America and Australia and lowest in East Asia, but no clear pattern in the heritability estimates across the birth-year cohorts emerged. Our findings do not support the hypothesis that heritability of height is lower in populations with low living standards than in affluent populations, nor that heritability of height will increase within a population as living standards improve. DOI: http://dx.doi.org/10.7554/eLife.20320.001 PMID:27964777

  20. The Human Release Hypothesis for biological invasions: human activity as a determinant of the abundance of invasive plant species.

    PubMed

    Zimmermann, Heike; Brandt, Patric; Fischer, Joern; Welk, Erik; von Wehrden, Henrik

    2014-01-01

    Research on biological invasions has increased rapidly over the past 30 years, generating numerous explanations of how species become invasive. While the mechanisms of invasive species establishment are well studied, the mechanisms driving abundance patterns (i.e. patterns of population density and population size) remain poorly understood. It is assumed that invasive species typically have higher abundances in their new environments than in their native ranges, and patterns of invasive species abundance differ between invaded regions. To explain differences in invasive species abundance, we propose the Human Release Hypothesis. In parallel to the established Enemy Release Hypothesis, this hypothesis states that the differences in abundance of invasive species are found between regions because population expansion is reduced in some regions through continuous land management and associated cutting of the invasive species. The Human Release Hypothesis does not negate other important drivers of species invasions, but rather should be considered as a potentially important complementary mechanism. We illustrate the hypothesis via a case study on an invasive rose species, and hypothesize which locations globally may be most likely to support high abundances of invasive species. We propose that more extensive empirical work on the Human Release Hypothesis could be useful to test its general applicability.

Top