Life-history strategies of ungulates

USGS Publications Warehouse

Leslie, David M.; Bowyer, R.T.; Kie, J.G.

1999-01-01

This Special Feature resulted from a symposium on life-history strategies of ungulates presented at the 78th Annual Meeting of the American Society of Mammalogists in Blacksburg, Virginia, in June 1998. The presentations at the symposium represented only a vignette of the wide variety of life-history strategies that exists among ungulates. The four papers that follow include treatises on birth-site selection of moose (Alces alces), sex-ratio correlates with dimorphism and risk of predation, optimal foraging relative to risk of predation, and the role of density dependence in shaping life-history traits of ungulates. A theme of risk of predation in shaping life-history traits is common to three of four papers.

Seeing How Far I've Come: The Impact of the Digital Sexual Life History Calendar on Young Adult Research Participants.

PubMed

Bay-Cheng, Laina Y

2017-01-01

The Digital Sexual Life History Calendar (d/SLHC) is a Web-based platform for collecting young adults' sexual histories. In addition to collecting diverse data, the d/SLHC was designed to benefit participants by enabling reflection on their sexual and relationship experiences in the context of other life events and circumstances. In a pilot study of the d/SLHC, survey data were collected to test whether creating a d/SLHC timeline had any impact on sexual well-being. A sample of 18- to 25-year-old participants recruited through Amazon Mechanical Turk (MTurk) completed an online survey about sexuality and relationships. Of those, 113 also completed d/SLHC timelines and 262 served as a comparison group. Six months later, participants from both groups were invited to complete a follow-up survey (total N = 249). Repeated-measures analysis of variance (ANOVA) results indicated that participants who completed d/SLHC timelines exhibited higher sexual esteem immediately following d/SLHC completion and at follow-up. No changes in sexual esteem were observed in the comparison group, and there were no differences between the groups with regard to sexual health behaviors and outcomes. These findings suggest that sexuality studies may have the potential to yield not only rich data for researchers but also rich experiences for participants.

"Life history space": a multivariate analysis of life history variation in extant and extinct Malagasy lemurs.

PubMed

Catlett, Kierstin K; Schwartz, Gary T; Godfrey, Laurie R; Jungers, William L

2010-07-01

Studies of primate life history variation are constrained by the fact that all large-bodied extant primates are haplorhines. However, large-bodied strepsirrhines recently existed. If we can extract life history information from their skeletons, these species can contribute to our understanding of primate life history variation. This is particularly important in light of new critiques of the classic "fast-slow continuum" as a descriptor of variation in life history profiles across mammals in general. We use established dental histological methods to estimate gestation length and age at weaning for five extinct lemur species. On the basis of these estimates, we reconstruct minimum interbirth intervals and maximum reproductive rates. We utilize principal components analysis to create a multivariate "life history space" that captures the relationships among reproductive parameters and brain and body size in extinct and extant lemurs. Our data show that, whereas large-bodied extinct lemurs can be described as "slow" in some fashion, they also varied greatly in their life history profiles. Those with relatively large brains also weaned their offspring late and had long interbirth intervals. These were not the largest of extinct lemurs. Thus, we distinguish size-related life history variation from variation that linked more strongly to ecological factors. Because all lemur species larger than 10 kg, regardless of life history profile, succumbed to extinction after humans arrived in Madagascar, we argue that large body size increased the probability of extinction independently of reproductive rate. We also provide some evidence that, among lemurs, brain size predicts reproductive rate better than body size. (c) 2010 Wiley-Liss, Inc.

Fishing-induced life-history changes degrade and destabilize harvested ecosystems.

PubMed

Kuparinen, Anna; Boit, Alice; Valdovinos, Fernanda S; Lassaux, Hélène; Martinez, Neo D

2016-02-26

Fishing is widely known to magnify fluctuations in targeted populations. These fluctuations are correlated with population shifts towards young, small, and more quickly maturing individuals. However, the existence and nature of the mechanistic basis for these correlations and their potential ecosystem impacts remain highly uncertain. Here, we elucidate this basis and associated impacts by showing how fishing can increase fluctuations in fishes and their ecosystem, particularly when coupled with decreasing body sizes and advancing maturation characteristic of the life-history changes induced by fishing. More specifically, using an empirically parameterized network model of a well-studied lake ecosystem, we show how fishing may both increase fluctuations in fish abundances and also, when accompanied by decreasing body size of adults, further decrease fish abundance and increase temporal variability of fishes' food resources and their ecosystem. In contrast, advanced maturation has relatively little effect except to increase variability in juvenile populations. Our findings illustrate how different mechanisms underlying life-history changes that may arise as evolutionary responses to intensive, size-selective fishing can rapidly and continuously destabilize and degrade ecosystems even after fishing has ceased. This research helps better predict how life-history changes may reduce fishes' resilience to fishing and ecosystems' resistance to environmental variations.

Fishing-induced life-history changes degrade and destabilize harvested ecosystems

NASA Astrophysics Data System (ADS)

Kuparinen, Anna; Boit, Alice; Valdovinos, Fernanda S.; Lassaux, Hélène; Martinez, Neo D.

2016-02-01

Fishing is widely known to magnify fluctuations in targeted populations. These fluctuations are correlated with population shifts towards young, small, and more quickly maturing individuals. However, the existence and nature of the mechanistic basis for these correlations and their potential ecosystem impacts remain highly uncertain. Here, we elucidate this basis and associated impacts by showing how fishing can increase fluctuations in fishes and their ecosystem, particularly when coupled with decreasing body sizes and advancing maturation characteristic of the life-history changes induced by fishing. More specifically, using an empirically parameterized network model of a well-studied lake ecosystem, we show how fishing may both increase fluctuations in fish abundances and also, when accompanied by decreasing body size of adults, further decrease fish abundance and increase temporal variability of fishes’ food resources and their ecosystem. In contrast, advanced maturation has relatively little effect except to increase variability in juvenile populations. Our findings illustrate how different mechanisms underlying life-history changes that may arise as evolutionary responses to intensive, size-selective fishing can rapidly and continuously destabilize and degrade ecosystems even after fishing has ceased. This research helps better predict how life-history changes may reduce fishes’ resilience to fishing and ecosystems’ resistance to environmental variations.

Life history variation in the Yazoo Shiner (Notropis rafinesquei) in three Mississippi streams

Treesearch

Wendell R. Hagg; Amy M. Commens-Carson; Melvin L. Warren

2007-01-01

We investigated the life history and demographics of Notropis rafinesquei(Cyprinidae) in three streams in north Mississippi, USA, over 2 y. Size at maturity (22.5-29.3 mm SL) and the timing and duration of the reproductive period (Apr.-Aug.) were similar among all three streams in both years. We consistently detected two young-of-the-year cohorts,...

Sex differences in cognitive ageing: testing predictions derived from life-history theory in a dioecious nematode.

PubMed

Zwoinska, Martyna K; Kolm, Niclas; Maklakov, Alexei A

2013-12-01

Life-history theory maintains that organisms allocate limited resources to different traits to maximize fitness. Learning ability and memory are costly and known to trade-off with longevity in invertebrates. However, since the relationship between longevity and fitness often differs between the sexes, it is likely that sexes will differentially resolve the trade-off between learning and longevity. We used an established associative learning paradigm in the dioecious nematode Caenorhabditis remanei, which is sexually dimorphic for lifespan, to study age-related learning ability in males and females. In particular, we tested the hypothesis that females (the shorter-lived sex) show higher learning ability than males early in life but senesce faster. Indeed, young females outperformed young males in learning a novel association between an odour (butanone) and food (bacteria). However, while learning ability and offspring production declined rapidly with age in females, males maintained high levels of these traits until mid-age. These results not only demonstrate sexual dimorphism in age-related learning ability but also suggest that it conforms to predictions derived from the life-history theory. © 2013.

Reconstructing life history of hominids and humans.

PubMed

Crews, Douglas E; Gerber, Linda M

2003-06-01

Aspects of life history, such as processes and timing of development, age at maturation, and life span are consistently associated with one another across the animal kingdom. Species that develop rapidly tend to mature and reproduce early, have many offspring, and exhibit shorter life spans (r-selection) than those that develop slowly, have extended periods of premature growth, mature later in life, reproduce later and less frequently, have few offspring and/or single births, and exhibit extended life spans (K-selection). In general, primates are among the most K-selected of species. A suite of highly derived life history traits characterizes humans. Among these are physically immature neonates, slowed somatic development both in utero and post-natally, late attainment of reproductive maturity and first birth, and extended post-mature survival. Exactly when, why, and through what types of evolutionary interactions this suite arose is currently the subject of much conjecture and debate. Humankind's biocultural adaptations have helped to structure human life history evolution in unique ways not seen in other animal species. Among all species, life history traits may respond rapidly to alterations in selective pressures through hormonal processes. Selective pressures on life history likely varied widely among hominids and humans over their evolutionary history. This suggests that current patterns of human growth, development, maturation, reproduction, and post-mature survival may be of recent genesis, rather then long-standing adaptations. Thus, life history patterns observed among contemporary human and chimpanzee populations may provide little insight to those that existed earlier in hominid/human evolution.

Social Structure and Individual Agency in Second Language Learning: Evidence from Three Life Histories

ERIC Educational Resources Information Center

Flowerdew, John; Miller, Lindsay

2008-01-01

This paper examines the issue of social structure and individual agency in language learning through the life histories of three young engineering graduates in Hong Kong. English is identified as an important form of cultural capital, which to a considerable extent determines the development of the three individuals, each of whom comes from a…

Population momentum across vertebrate life histories

USGS Publications Warehouse

Koons, D.N.; Grand, J.B.; Arnold, J.M.

2006-01-01

Population abundance is critically important in conservation, management, and demographic theory. Thus, to better understand how perturbations to the life history affect long-term population size, we examined population momentum for four vertebrate classes with different life history strategies. In a series of demographic experiments we show that population momentum generally has a larger effect on long-term population size for organisms with long generation times than for organisms with short generation times. However, patterns between population momentum and generation time varied across taxonomic groups and according to the life history parameter that was changed. Our findings indicate that momentum may be an especially important aspect of population dynamics for long-lived vertebrates, and deserves greater attention in life history studies. Further, we discuss the importance of population momentum in natural resource management, pest control, and conservation arenas. ?? 2006 Elsevier B.V. All rights reserved.

Primates and the Evolution of Long-Slow Life Histories

PubMed Central

Jones, James Holland

2011-01-01

Summary Primates are characterized by relatively late ages at first reproduction, long lives and low fertility. Together, these traits define a life-history of reduced reproductive effort. Understanding the optimal allocation of reproductive effort, and specifically reduced reproductive effort, has been one of the key problems motivating the development of life history theory. Because of their unusual constellation of life-history traits, primates play an important role in the continued development of life history theory. In this review, I present the evidence for the reduced reproductive effort life histories of primates and discuss the ways that such life-history tactics are understood in contemporary theory. Such tactics are particularly consistent with the predictions of stochastic demographic models, suggesting a key role for environmental variability in the evolution of primate life histories. The tendency for primates to specialize in high-quality, high-variability food items may make them particularly susceptible to environmental variability and explain their low reproductive-effort tactics. I discuss recent applications of life history theory to human evolution and emphasize the continuity between models used to explain peculiarities of human reproduction and senescence with the long, slow life histories of primates more generally. PMID:21959161

The History and Accomplishments of the LIVESTRONG Young Adult Alliance.

PubMed

Mathews-Bradshaw, Beth; Johnson, Rebecca; Kaplan, Stuart; Craddock, Kelli; Hayes-Lattin, Brandon

2011-03-01

This article outlines the history, background, and accomplishments of the LIVESTRONG Young Adult Alliance. The LIVESTRONG Young Adult Alliance, a program of the Lance Armstrong Foundation, was developed as a vehicle for a strategic plan designed to implement the Adolescent and Young Adult Oncology Progress Review Group (AYAO PRG) recommendations. The AYAO PRG was co-sponsored by Lance Armstrong Foundation and the National Cancer Institute (NCI); both LIVESTRONG and NCI provide strategic oversight and guidance to the Alliance. Highlights and accomplishments: The Alliance accomplishments include the publication of disease-specific retrospective analyses, funding of an AYA cohort study and biorepository proposal, publication of two position statements on guidelines for care of AYAs with cancer and training for AYA oncology health professionals, promotion of an international charter of rights for AYA cancer patients, creation and distribution of a survey to college health professionals, creation and implementation of a Cancer Centers Working Group and Institutional Review Board Toolkit, and continued growth and collaboration through an annual meeting. The growth and success of the Alliance has coincided with the growth of AYA oncology as a field. The collaborative environment of the Alliance draws together a diverse group of individuals united in the effort to increase survival rates and improve the quality of life for adolescents and young adults diagnosed with cancer.

"Our Journey through Time": An Oral History Project Carried out by Young People with Learning Disabilities

ERIC Educational Resources Information Center

Bentley, Sarah; Nicholls, Rickie; Price, Maxine; Wilkinson, Aaron; Purcell, Matthew; Woodhall, Martin; Walmsley, Jan

2011-01-01

We are five young people with learning disabilities who found out about the history of hospitals for people with learning disabilities in our area, and made a film about the project. The project taught us what life had been like for some people with learning disabilities only 30 years ago. It was very different to our lives; we have more choice,…

Personal Narratives in Life History Research

ERIC Educational Resources Information Center

Germeten, Sidsel

2013-01-01

In this article I discuss how to create personal narratives in life history research methodology. People tell stories of their lives, and the researchers make these stories into life histories. Based on theoretical perspectives on "discourse" inspired by Michel Foucault, narratives are seen as ways of positioning oneself as a…

Lemur Biorhythms and Life History Evolution.

PubMed

Hogg, Russell T; Godfrey, Laurie R; Schwartz, Gary T; Dirks, Wendy; Bromage, Timothy G

2015-01-01

Skeletal histology supports the hypothesis that primate life histories are regulated by a neuroendocrine rhythm, the Havers-Halberg Oscillation (HHO). Interestingly, subfossil lemurs are outliers in HHO scaling relationships that have been discovered for haplorhine primates and other mammals. We present new data to determine whether these species represent the general lemur or strepsirrhine condition and to inform models about neuroendocrine-mediated life history evolution. We gathered the largest sample to date of HHO data from histological sections of primate teeth (including the subfossil lemurs) to assess the relationship of these chronobiological measures with life history-related variables including body mass, brain size, age at first female reproduction, and activity level. For anthropoids, these variables show strong correlations with HHO conforming to predictions, though body mass and endocranial volume are strongly correlated with HHO periodicity in this group. However, lemurs (possibly excepting Daubentonia) do not follow this pattern and show markedly less variability in HHO periodicity and lower correlation coefficients and slopes. Moreover, body mass is uncorrelated, and brain size and activity levels are more strongly correlated with HHO periodicity in these animals. We argue that lemurs evolved this pattern due to selection for risk-averse life histories driven by the unpredictability of the environment in Madagascar. These results reinforce the idea that HHO influences life history evolution differently in response to specific ecological selection regimes.

Lemur Biorhythms and Life History Evolution

PubMed Central

Hogg, Russell T.; Godfrey, Laurie R.; Schwartz, Gary T.; Dirks, Wendy; Bromage, Timothy G.

2015-01-01

Skeletal histology supports the hypothesis that primate life histories are regulated by a neuroendocrine rhythm, the Havers-Halberg Oscillation (HHO). Interestingly, subfossil lemurs are outliers in HHO scaling relationships that have been discovered for haplorhine primates and other mammals. We present new data to determine whether these species represent the general lemur or strepsirrhine condition and to inform models about neuroendocrine-mediated life history evolution. We gathered the largest sample to date of HHO data from histological sections of primate teeth (including the subfossil lemurs) to assess the relationship of these chronobiological measures with life history-related variables including body mass, brain size, age at first female reproduction, and activity level. For anthropoids, these variables show strong correlations with HHO conforming to predictions, though body mass and endocranial volume are strongly correlated with HHO periodicity in this group. However, lemurs (possibly excepting Daubentonia) do not follow this pattern and show markedly less variability in HHO periodicity and lower correlation coefficients and slopes. Moreover, body mass is uncorrelated, and brain size and activity levels are more strongly correlated with HHO periodicity in these animals. We argue that lemurs evolved this pattern due to selection for risk-averse life histories driven by the unpredictability of the environment in Madagascar. These results reinforce the idea that HHO influences life history evolution differently in response to specific ecological selection regimes. PMID:26267241

Life histories in occupational therapy clinical practice.

PubMed

Frank, G

1996-04-01

This article defines and compares several narrative methods used to describe and interpret patients' lives. The biographical methods presented are case histories, life-charts, life histories, life stories, assisted autobiography, hermeneutic case reconstruction, therapeutic employment, volitional narratives, and occupational storytelling and story making. Emphasis is placed the clinician as a collaborator and interpreter of the patient's life through ongoing interactions and dialogue.

Primates and the evolution of long, slow life histories.

PubMed

Jones, James Holland

2011-09-27

Primates are characterized by relatively late ages at first reproduction, long lives and low fertility. Together, these traits define a life-history of reduced reproductive effort. Understanding the optimal allocation of reproductive effort, and specifically reduced reproductive effort, has been one of the key problems motivating the development of life-history theory. Because of their unusual constellation of life-history traits, primates play an important role in the continued development of life-history theory. In this review, I present the evidence for the reduced reproductive effort life histories of primates and discuss the ways that such life-history tactics are understood in contemporary theory. Such tactics are particularly consistent with the predictions of stochastic demographic models, suggesting a key role for environmental variability in the evolution of primate life histories. The tendency for primates to specialize in high-quality, high-variability food items may make them particularly susceptible to environmental variability and explains their low reproductive-effort tactics. I discuss recent applications of life-history theory to human evolution and emphasize the continuity between models used to explain peculiarities of human reproduction and senescence with the long, slow life histories of primates more generally. Copyright © 2011 Elsevier Ltd. All rights reserved.

Life-History Traits and Population Structure of Pederson Cleaner Shrimps Ancylomenes pedersoni.

PubMed

Gilpin, Jessica A; Chadwick, Nanette E

2017-12-01

Cleaner organisms perform key functional roles in reducing rates of parasitism in marine communities. Pederson cleaner shrimps Ancylomenes pedersoni are major cleaners of reef fishes in the tropical western Atlantic and form obligate symbioses with host sea anemones. Information about their life-history traits would contribute to understanding how symbiosis impacts life-history evolution in crustaceans, but little is known about patterns of growth and reproduction in this anemone shrimp. We quantified growth, sexual reproduction, senescence, and mortality in individuals of A. pedersoni under laboratory conditions and their abundance and population size structure on coral reefs in St. Thomas, U.S. Virgin Islands. Von Bertalanffy growth curves were fitted to the data to determine age-size relationships, and the Beverton-Holt model was used to estimate mortality rates and size at maximum yield. Individuals grew rapidly when young, then slowed their growth after reaching sexual maturity at ~6 months. Individuals were gonochoric, with males attaining significantly smaller body sizes and shorter life spans than did females. Prior to death at <2 years, members of both genders exhibited senescence during which they ceased reproducing, shrank (females only), and decreased their activity levels over ~1-4 weeks. Field populations were abundant and composed mostly of juveniles during both years examined. Populations appeared to be stable but highly dynamic in terms of individuals, reaching maximum yield at 4 months of age. We conclude that obligate symbiosis with large sea anemones and cleaner mutualism with reef fishes both contribute to explaining aspects of the life history of Pederson shrimps, especially their apparent mating system of pure-search polygynandry. This life-history information also provides a scientific basis for sustainable fishery management and aquaculture of this key coral reef organism.

Globalization and Life History Research: Fragments of a Life Foretold

ERIC Educational Resources Information Center

Tierney, William G.

2010-01-01

The goal of this paper is to understand, by way of a life history of one low-income working-class youth, how globalization impacts the working class in a developing nation. The concept of globalization and the method of life history seem diametrically opposed. Globalization is an idea about large social forces that impact the economic and material…

Nutrition shapes life-history evolution across species

PubMed Central

Swanson, Eli M.; Espeset, Anne; Mikati, Ihab; Bolduc, Isaac; Kulhanek, Robert; White, William A.; Kenzie, Susan

2016-01-01

Nutrition is a key component of life-history theory, yet we know little about how diet quality shapes life-history evolution across species. Here, we test whether quantitative measures of nutrition are linked to life-history evolution across 96 species of butterflies representing over 50 independent diet shifts. We find that butterflies feeding on high nitrogen host plants as larvae are more fecund, but their eggs are smaller relative to their body size. Nitrogen and sodium content of host plants are also both positively related to eye size. Some of these relationships show pronounced lineage-specific effects. Testis size is not related to nutrition. Additionally, the evolutionary timing of diet shifts is not important, suggesting that nutrition affects life histories regardless of the length of time a species has been adapting to its diet. Our results suggest that, at least for some lineages, species with higher nutrient diets can invest in a range of fitness-related traits like fecundity and eye size while allocating less to each egg as offspring have access to a richer diet. These results have important implications for the evolution of life histories in the face of anthropogenic changes in nutrient availability. PMID:27412282

Life history dependent morphometric variation in stream-dwelling Atlantic salmon

USGS Publications Warehouse

Letcher, B.H.

2003-01-01

The time course of morphometric variation among life histories for stream-dwelling Atlantic salmon (Salmo salar L.) parr (age-0+ to age-2+) was analyzed. Possible life histories were combinations of parr maturity status in the autumn (mature or immature) and age at outmigration (smolt at age-2+ or later age). Actual life histories expressed with enough fish for analysis in the 1997 cohort were immature/age-2+ smolt, mature/age-2 +smolt, and mature/age-2+ non-smolt. Tagged fish were assigned to one of the three life histories and digital pictures from the field were analyzed using landmark-based geometric morphometrics. Results indicated that successful grouping of fish according to life history varied with fish age, but that fish could be grouped before the actual expression of the life histories. By March (age-1+), fish were successfully grouped using a descriptive discriminant function and successful assignment ranged from 84 to 97% for the remainder of stream residence. A jackknife of the discriminant function revealed an average life history prediction success of 67% from age-1+ summer to smolting. Low sample numbers for one of the life histories may have limited prediction success. A MANOVA on the shape descriptors (relative warps) also indicated significant differences in shape among life histories from age-1+ summer through to smolting. Across all samples, shape varied significantly with size. Within samples, shape did not vary significantly with size for samples from December (age-0+) to May (age-1+). During the age-1+ summer however, shape varied significantly with size, but the relationship between shape and size was not different among life histories. In the autumn (age-1+) and winter (age-2+), life history differences explained a significant portion of the change in shape with size. Life history dependent morphometric variation may be useful to indicate the timing of early expressions of life history variation and as a tool to explore temporal and

Family history associated with pelvic organ prolapse in young women.

PubMed

Alcalay, Menachem; Stav, Kobi; Eisenberg, Vered H

2015-12-01

Pelvic organ prolapse (POP) among young women is a relatively rare disorder with a unique clinical background. The objective of our study was to investigate the relative risk factors for POP and the relationship between family history and POP development in young women. In a retrospective longitudinal study we investigated 26 young patients (age <45 years) who underwent POP surgery and compared them to a control group of 26 patients (age >55 years) who underwent similar surgery and were matched with regard to parity. All women were interviewed for family history of POP, POP surgery among first-degree relatives, and hernia repair. Family history of POP was five times more prevalent among women in the study group than in the control group (46 % vs. 8 %, P < 0.01). Moreover, POP surgery among the first-degree relatives was significantly more prevalent in the study group (23.1 % vs. 3.8 %, p < 0.05). The prevalence of a family history of POP in more than one first-degree relative (11.5 % vs. 3.84 %, p = 0.3) and the family history of hernia repair among first-degree relatives (11.5 % vs. 15.4 %) did not differ between the groups. A family history of POP is significantly more common in younger affected women than in older affected women. We suggest that future genetic studies should concentrate on this specific population.

Life history diversity in Klamath River steelhead

USGS Publications Warehouse

Hodge, Brian W.; Wilzbach, Peggy; Duffy, Walter G.; Quinones, Rebecca M.; Hobbs, James A.

2016-01-01

Oncorhynchus mykiss exhibits a vast array of life histories, which increases its likelihood of persistence by spreading risk of extirpation among different pathways. The Klamath River basin (California–Oregon) provides a particularly interesting backdrop for the study of life history diversity in O. mykiss, in part because the river is slated for a historic and potentially influential dam removal and habitat recolonization project. We used scale and otolith strontium isotope (87Sr/86Sr) analyses to characterize life history diversity in wildO. mykiss from the lower Klamath River basin. We also determined maternal origin (anadromous or nonanadromous) and migratory history (anadromous or nonanadromous) of O. mykiss and compared length and fecundity at age between anadromous (steelhead) and nonanadromous (Rainbow Trout) phenotypes of O. mykiss. We identified a total of 38 life history categories at maturity, which differed in duration of freshwater and ocean rearing, age at maturation, and incidence of repeat spawning. Approximately 10% of adult fish sampled were nonanadromous. Rainbow Trout generally grew faster in freshwater than juvenile steelhead; however, ocean growth afforded adult steelhead greater length and fecundity than adult Rainbow Trout. Although 75% of individuals followed the migratory path of their mother, steelhead produced nonanadromous progeny and Rainbow Trout produced anadromous progeny. Overall, we observed a highly diverse array of life histories among Klamath River O. mykiss. While this diversity should increase population resilience, recent declines in the abundance of Klamath River steelhead suggest that life history diversity alone is not sufficient to stabilize a population. Our finding that steelhead and Rainbow Trout give rise to progeny of the alternate form (1) suggests that dam removal might lead to a facultatively anadromous O. mykiss population in the upper basin and (2) raises the question of whether both forms of

Primate energy expenditure and life history

PubMed Central

Pontzer, Herman; Raichlen, David A.; Gordon, Adam D.; Schroepfer-Walker, Kara K.; Hare, Brian; O’Neill, Matthew C.; Muldoon, Kathleen M.; Dunsworth, Holly M.; Wood, Brian M.; Isler, Karin; Burkart, Judith; Irwin, Mitchell; Shumaker, Robert W.; Lonsdorf, Elizabeth V.; Ross, Stephen R.

2014-01-01

Humans and other primates are distinct among placental mammals in having exceptionally slow rates of growth, reproduction, and aging. Primates’ slow life history schedules are generally thought to reflect an evolved strategy of allocating energy away from growth and reproduction and toward somatic investment, particularly to the development and maintenance of large brains. Here we examine an alternative explanation: that primates’ slow life histories reflect low total energy expenditure (TEE) (kilocalories per day) relative to other placental mammals. We compared doubly labeled water measurements of TEE among 17 primate species with similar measures for other placental mammals. We found that primates use remarkably little energy each day, expending on average only 50% of the energy expected for a placental mammal of similar mass. Such large differences in TEE are not easily explained by differences in physical activity, and instead appear to reflect systemic metabolic adaptation for low energy expenditures in primates. Indeed, comparisons of wild and captive primate populations indicate similar levels of energy expenditure. Broad interspecific comparisons of growth, reproduction, and maximum life span indicate that primates’ slow metabolic rates contribute to their characteristically slow life histories. PMID:24474770

Work-Life Conflict among Young Academics: Antecedents and Gender Effects

ERIC Educational Resources Information Center

Dorenkamp, Isabelle; Süß, Stefan

2017-01-01

Aligning work and private life is a significant challenge for young academics because of demanding working conditions (e.g. high workload, low job security). It is particularly strong for young female academics due to growing family responsibilities. Our study aims to identify the factors influencing the work-life conflict of young academics and…

Self-rated quality of life among the young unemployed and the young in work in northern Sweden.

PubMed

Hultman, Barbro; Hemlin, Sven

2008-01-01

This study analysed self-assessed quality of life (QoL), using a QoL questionnaire (Hörnquist's QLcs) covering life spheres, somatic health, mental well-being, cognitive ability, social and family life, activity, financial situation, meaning in life and a global score "entire life", for young people aged 18-24 in a population-based cross-sectional study in northern Sweden. Of these, 651 were unemployed and 2802 were in work (employed, students and in military service). Results showed that the young unemployed exhibited poorer QoL than the young in work and the greatest difference was found regarding their financial situation. Young men rated somatic health and mental well-being higher than young women. However, QoL in other essential domains was rated higher by young women in work. Close friends and money reserve were important for all participants, no matter whether they were employed or not. The risk of being young and unemployed was greater if the person had a worse financial situation, shorter education, and fewer leisure activities with other people. Finally, it was concluded that while QoL is poorer when in unemployment - both for the young and those who are older (aged 25-64) - psychological well-being, in contrast to several previous studies, is even poorer for young people than for those who are older. This is worrying in a public health perspective and could have implications for unemployment policies for younger and less well-educated age groups.

Life-History Patterns of Lizards of the World.

PubMed

Mesquita, Daniel O; Costa, Gabriel C; Colli, Guarino R; Costa, Taís B; Shepard, Donald B; Vitt, Laurie J; Pianka, Eric R

2016-06-01

Identification of mechanisms that promote variation in life-history traits is critical to understand the evolution of divergent reproductive strategies. Here we compiled a large life-history data set (674 lizard populations, representing 297 species from 263 sites globally) to test a number of hypotheses regarding the evolution of life-history traits in lizards. We found significant phylogenetic signal in most life-history traits, although phylogenetic signal was not particularly high. Climatic variables influenced the evolution of many traits, with clutch frequency being positively related to precipitation and clutches of tropical lizards being smaller than those of temperate species. This result supports the hypothesis that in tropical and less seasonal climates, many lizards tend to reproduce repeatedly throughout the season, producing smaller clutches during each reproductive episode. Our analysis also supported the hypothesis that viviparity has evolved in lizards as a response to cooler climates. Finally, we also found that variation in trait values explained by clade membership is unevenly distributed among lizard clades, with basal clades and a few younger clades showing the most variation. Our global analyses are largely consistent with life-history theory and previous results based on smaller and scattered data sets, suggesting that these patterns are remarkably consistent across geographic and taxonomic scales.

Deciphering life history transcriptomes in different environments

PubMed Central

Etges, William J.; Trotter, Meredith V.; de Oliveira, Cássia C.; Rajpurohit, Subhash; Gibbs, Allen G.; Tuljapurkar, Shripad

2014-01-01

We compared whole transcriptome variation in six preadult stages and seven adult female ages in two populations of cactophilic Drosophila mojavensis reared on two host plants in order to understand how differences in gene expression influence standing life history variation. We used Singular Value Decomposition (SVD) to identify dominant trajectories of life cycle gene expression variation, performed pair-wise comparisons of stage and age differences in gene expression across the life cycle, identified when genes exhibited maximum levels of life cycle gene expression, and assessed population and host cactus effects on gene expression. Life cycle SVD analysis returned four significant components of transcriptional variation, revealing functional enrichment of genes responsible for growth, metabolic function, sensory perception, neural function, translation and aging. Host cactus effects on female gene expression revealed population and stage specific differences, including significant host plant effects on larval metabolism and development, as well as adult neurotransmitter binding and courtship behavior gene expression levels. In 3 - 6 day old virgin females, significant up-regulation of genes associated with meiosis and oogenesis was accompanied by down-regulation of genes associated with somatic maintenance, evidence for a life history tradeoff. The transcriptome of D. mojavensis reared in natural environments throughout its life cycle revealed core developmental transitions and genome wide influences on life history variation in natural populations. PMID:25442828

Experimental reintroduction reveals novel life-history variation in Laysan Ducks (Anas laysanensis)

USGS Publications Warehouse

Walters, Jeffrey R.; Reynolds, Michelle H.

2013-01-01

Subfossil remains indicate that the Laysan Duck (Anas laysanensis) formerly occurred throughout the Hawaiian archipelago, but for more than 150 years it has been confined to a single, small atoll in the northwestern chain, Laysan Island. In 2004–2005, 42 ducks were reintroduced from Laysan to Midway Atoll, where they exhibited variation in life history never observed on Laysan. On Laysan, females have never been observed to breed successfully at age 1 year and few attempt it, whereas on Midway, females routinely raised young at <1 year of age. Mean (± SD) clutch size on Midway (7.0 ± 1.1, n = 41) was larger than the maximum clutch size of six eggs observed on Laysan. On Midway, renesting following nest failure (0.55 probability, n = 27) and double brooding (0.50, n = 54) were routine, and two instances of triple brooding were observed, whereas on Laysan, renesting and double brooding are rare (0.05 probability for both during our study; n = 21 and 19, respectively) and triple brooding has never been observed. Other novel life history on Midway included early cessation of parental care to renest. Altered life history on Midway is likely related to better feeding conditions and low population density compared with Laysan. An especially intriguing possibility is that the phenotypic plasticity observed represents exposure of hidden reaction norms evolved when the species inhabited a range of environments, but several alternative explanations exist. Future reintroductions of this species may provide opportunities to test hypotheses about mechanisms underlying phenotypic plasticity.

Are personality differences in a small iteroparous mammal maintained by a life-history trade-off?

PubMed Central

Dammhahn, Melanie

2012-01-01

Despite increasing interest, animal personality is still a puzzling phenomenon. Several theoretical models have been proposed to explain intraindividual consistency and interindividual variation in behaviour, which have been primarily supported by qualitative data and simulations. Using an empirical approach, I tested predictions of one main life-history hypothesis, which posits that consistent individual differences in behaviour are favoured by a trade-off between current and future reproduction. Data on life-history were collected for individuals of a natural population of grey mouse lemurs (Microcebus murinus). Using open-field and novel-object tests, I quantified variation in activity, exploration and boldness for 117 individuals over 3 years. I found systematic variation in boldness between individuals of different residual reproductive value. Young males with low current but high expected future fitness were less bold than older males with high current fecundity, and males might increase in boldness with age. Females have low variation in assets and in boldness with age. Body condition was not related to boldness and only explained marginal variation in exploration. Overall, these data indicate that a trade-off between current and future reproduction might maintain personality variation in mouse lemurs, and thus provide empirical support of this life-history trade-off hypothesis. PMID:22398164

The effect of life expectancy on aggression and generativity: a life history perspective.

PubMed

Dunkel, Curtis S; Mathes, Eugene; Papini, Dennis R

2010-09-23

Following a model that is inclusive of both dispositional and situational influences on life-history behaviors and attitudes, the effect of life expectancies on aggression and generativity was examined. Consistent with the hypotheses it was found that shorter life expectancies led to an increase in the desire to aggress and a decrease in the desire to engage in generative behaviors. The results are discussed in terms of how life history theory can be used to frame research on person-situation interactions.

Academic Oral History: Life Review in Spite of Itself.

ERIC Educational Resources Information Center

Ryant, Carl

The process and content of the life review should not be separated from the creation of an oral history. Several projects, undertaken at the University of Louisville Oral History Center, support the therapeutic aspects of reminiscence. The dichotomy between oral history, as an historical database, and life review, as a therapeutic exercise, breaks…

Phenological sequences reveal aggregate life history response to climatic warming.

PubMed

Post, Eric S; Pedersen, Christian; Wilmers, Christopher C; Forchhammer, Mads C

2008-02-01

Climatic warming is associated with organisms breeding earlier in the season than is typical for their species. In some species, however, response to warming is more complex than a simple advance in the timing of all life history events preceding reproduction. Disparities in the extent to which different components of the reproductive phenology of organisms vary with climatic warming indicate that not all life history events are equally responsive to environmental variation. Here, we propose that our understanding of phenological response to climate change can be improved by considering entire sequences of events comprising the aggregate life histories of organisms preceding reproduction. We present results of a two-year warming experiment conducted on 33 individuals of three plant species inhabiting a low-arctic site. Analysis of phenological sequences of three key events for each species revealed how the aggregate life histories preceding reproduction responded to warming, and which individual events exerted the greatest influence on aggregate life history variation. For alpine chickweed (Cerastium alpinum), warming elicited a shortening of the duration of the emergence stage by 2.5 days on average, but the aggregate life history did not differ between warmed and ambient plots. For gray willow (Salix glauca), however, all phenological events monitored occurred earlier on warmed than on ambient plots, and warming reduced the aggregate life history of this species by 22 days on average. Similarly, in dwarf birch (Betula nana), warming advanced flower bud set, blooming, and fruit set and reduced the aggregate life history by 27 days on average. Our approach provides important insight into life history responses of many organisms to climate change and other forms of environmental variation. Such insight may be compromised by considering changes in individual phenological events in isolation.

Implications of life-history strategies for obesity

PubMed Central

Maner, Jon K.; Dittmann, Andrea; Meltzer, Andrea L.; McNulty, James K.

2017-01-01

The association between low socioeconomic status (SES) and obesity is well documented. In the current research, a life history theory (LHT) framework provided an explanation for this association. Derived from evolutionary behavioral science, LHT emphasizes how variability in exposure to unpredictability during childhood gives rise to individual differences in a range of social psychological processes across the life course. Consistent with previous LHT research, the current findings suggest that exposure to unpredictability during childhood (a characteristic common to low SES environments) is associated with the adoption of a fast life-history strategy, one marked by impulsivity and a focus on short-term goals. We demonstrate that a fast life-history strategy, in turn, was associated with dysregulated weight-management behaviors (i.e., eating even in the absence of hunger), which were predictive of having a high body mass index (BMI) and being obese. In both studies, findings held while controlling for participants’ current socioeconomic status, suggesting that obesity is rooted in childhood experiences. A serial mediation model in study 2 confirmed that effects of childhood SES on adult BMI and obesity can be explained in part by exposure to unpredictability, the adoption of a fast life-history strategy, and dysregulated-eating behaviors. These findings suggest that weight problems in adulthood may be rooted partially in early childhood exposure to unpredictable events and environments. LHT provides a valuable explanatory framework for understanding the root causes of obesity. PMID:28739939

Quality of life, self-esteem and worries in young adult survivors of childhood cancer.

PubMed

Langeveld, N E; Grootenhuis, M A; Voûte, P A; de Haan, R J; van den Bos, C

2004-12-01

This study assessed quality of life, self-esteem and worries in young adult survivors of childhood cancer compared to a group of young adults with no history of cancer. The impact of demographic, medical and treatment factors and self-esteem on survivors' quality of life and worries was studied. Participants were 400 long-term survivors (LTS) of childhood cancer (age range 16-49 years, 45% female) who had completed treatment an average of 16 years previously and 560 persons (age range 16-53 years, 55% female) with no history of cancer. All participants completed the MOS-24 (Medical Outcome Study Scale), a Worry questionnaire consisting of three scales (cancer-specific concerns, general health concerns, present and future concerns), and the Rosenberg Self-Esteem Scale. Small to moderate differences were found in mean MOS-24 scores between the LTS group and controls (range effect sizes -0.36-0.22). No significant difference was found in the mean self-esteem scores between LTS and controls. Female LTS had more cancer-specific concerns than male LTS. In several related areas of general health, self-image and dying, the LTS group reported less worries than controls, but LTS worried significantly more about their fertility, getting/changing a job and obtaining insurance's. Multiple linear regression analysis revealed that female gender, unemployment, severe late effects/health problems and a low self-esteem were predictors of worse quality of life in survivors. In addition, age at follow-up, unemployment, years since completion of therapy and a low self-esteem were associated with a higher degree of survivors' worries. Quality of life and the level of self-esteem in LTS of childhood cancer is not different from their peers. Although many LTS worried not more or even less about health issues than their peers, they often are concerned about some present and future concerns. The investigated factors could explain poor quality of life and worries only to a limited extent

Human evolution, life history theory, and the end of biological reproduction.

PubMed

Last, Cadell

2014-01-01

Throughout primate history there have been three major life history transitions towards increasingly delayed sexual maturation and biological reproduction, as well as towards extended life expectancy. Monkeys reproduce later and live longer than do prosimians, apes reproduce later and live longer than do monkeys, and humans reproduce later and live longer than do apes. These life history transitions are connected to increased encephalization. During the last life history transition from apes to humans, increased encephalization co-evolved with increased dependence on cultural knowledge for energy acquisition. This led to a dramatic pressure for more energy investment in growth over current biological reproduction. Since the industrial revolution socioeconomic development has led to even more energy being devoted to growth over current biological reproduction. I propose that this is the beginning of an ongoing fourth major primate life history transition towards completely delayed biological reproduction and an extension of the evolved human life expectancy. I argue that the only fundamental difference between this primate life history transition and previous life history transitions is that this transition is being driven solely by cultural evolution, which may suggest some deeper evolutionary transition away from biological evolution is already in the process of occurring.

The Dark Triad Traits from a Life History Perspective in Six Countries.

PubMed

Jonason, Peter K; Foster, Joshua D; Egorova, Marina S; Parshikova, Oksana; Csathó, Árpád; Oshio, Atsushi; Gouveia, Valdiney V

2017-01-01

Work on the Dark Triad traits has benefited from the use of a life history framework but it has been limited to primarily Western samples and indirect assessments of life history strategies. Here, we examine how the Dark Triad traits (i.e., psychopathy, Machiavellianism, and narcissism) relate to two measures of individual differences in life history strategies. In Study 1 ( N = 937), we replicated prior observed links between life history strategies, as measured by the Mini- K , and the Dark Triad traits using samples recruited from three countries. In Study 2 ( N = 1032), we measured life history strategies using the Consideration of Future Consequences Scale and correlated it with the Dark Triad traits in samples recruited from three additional countries. While there was some variability across participants' sex and country, the results were generally consistent in that psychopathy and (to a lesser extent) Machiavellianism were related to faster life history strategies and narcissism was related to slower life history strategies. These results add cross-cultural data and the use of two measures of life history speed to understand the Dark Triad traits from a life history perspective.

Heritability of and strong single gene (Pgi) effects on life-history traits in the Glanville fritillary butterfly.

PubMed

Klemme, I; Hanski, I

2009-09-01

We estimated broad-sense heritabilities (H(2)) of 13 female and seven male life-history traits of the Glanville fritillary butterfly (Melitaea cinxia) under semi-natural conditions in a large outdoor population cage. The analysis was based on full-sib families collected as young larvae in the field and reared under common garden conditions. We found significant genetic variance in female lifespan, fecundity, number of matings and host-plant preference as well as in male body mass and mobility. Apart from host-plant preference, female traits that were more strongly correlated with lifetime reproductive success (LRS; measured as total number of eggs laid) had higher H(2). LRS itself exhibited significant heritability. Host-plant preference had very high H(2), consistent with a previously reported genetically determined geographical cline in host-plant preference in the study area. Lifespan and egg hatching rate were significantly associated with a SNP in the coding region of the Pgi gene, for which there is previous evidence for balancing selection. Selection on Pgi, which furthermore shows spatial and temporal variation, may maintain genetic variance in fitness-related life-history traits. In contrast, we found no strong evidence for life-history trade-offs.

Exploring life history characteristics of naturalized versus stocked chinook

USGS Publications Warehouse

Rogers, Mark W.; Kerns, Janice A; Bunnell, David B.; Claramunt, Randall M.; Collingsworth, Paris D.

2011-01-01

Naturalization of stocked populations can result in divergence of life-history traits from domestic stocks. Lake Michigan supports popular Chinook (Oncorhynchus tshawytscha) Salmon fisheries that have been sustained by stocking since the late 1960s. Natural recruitment of Chinook Salmon in Lake Michigan has increased in the last few decades and currently contributes over 50% of Chinook Salmon recruits. Samples collected as part of a lakewide mass-marking of Lake Michigan Chinook Salmon, starting with the 2006 year class, indicated hatchery fish average 30-mm longer and 130 grams heavier than naturalized fish at age-1. We hypothesized that selective forces differ for naturalized and hatchery populations resulting in divergent life-history characteristics with implications for Chinook Salmon population production and the Lake Michigan fishery. Specific life-history metrics of interest include: age- and size- at maturity, spawning run timing, fecundity, and sex ratio. Objectives: We evaluated life history characteristics between naturally recruited and stocked Chinook Salmon in Lake Michigan to help discern potential changes resulting from naturalization and implications for fisheries. A. Conduct an analysis of historical data to determine if life-history parameters changed through time as the Chinook Salmon population became increasingly naturalized. B. Conduct a two-year field study of naturalized and hatchery stocked Chinook Salmon spawning populations to quantify differences in life-history metrics of adults. C. Determine if reproductive potential differs between naturalized and hatchery stocked Chinook salmon by measuring egg thiamine levels.

Life History and Identity

ERIC Educational Resources Information Center

Tierney, William G.

2013-01-01

This article uses the life history method to chronicle the challenges of a low-income, first-generation student en route to college. The paper addresses three questions: how Manuel navigates college and related topics such as roommates, family, and money; how he creates social networks; and how he works with adults such as teachers and…

Unequal burdens of loss: examining the frequency and timing of homicide deaths experienced by young Black men across the life course.

PubMed

Smith, Jocelyn R

2015-07-01

I examined the frequency and developmental timing of traumatic loss resulting from the health disparity of homicide among young Black men in Baltimore, Maryland. Using a modified grounded theory approach, I conducted in-depth semistructured interviews with 40 Black men (aged 18-24 years) from January 2012 to June 2013. I also constructed adapted life history calendar tools using chronologies of loss, and (1) provided a comprehensive history of loss, (2) determined a specific frequency of homicide deaths, (3) indicated participants' relationship to the decedents, and (4) identified the developmental timing of deaths. On average, participants knew 3 homicide victims who were overwhelmingly peers. Participant experiences of homicide death started in early childhood, peaked in adolescence, and persisted into emerging adulthood. The traumatic loss of peer homicide was a significant developmental turning point and disrupted participants' social networks. The traumatic loss of peer homicide was a prevalent life course experience for young Black men and identified the need for trauma- and grief-informed interventions. Future research is needed to examine the physical and psychosocial consequences, coping resources and strategies, and developmental implications of traumatic loss for young Black men in urban contexts.

Unequal Burdens of Loss: Examining the Frequency and Timing of Homicide Deaths Experienced by Young Black Men Across the Life Course

PubMed Central

2015-01-01

Objectives. I examined the frequency and developmental timing of traumatic loss resulting from the health disparity of homicide among young Black men in Baltimore, Maryland. Methods. Using a modified grounded theory approach, I conducted in-depth semistructured interviews with 40 Black men (aged 18–24 years) from January 2012 to June 2013. I also constructed adapted life history calendar tools using chronologies of loss, and (1) provided a comprehensive history of loss, (2) determined a specific frequency of homicide deaths, (3) indicated participants’ relationship to the decedents, and (4) identified the developmental timing of deaths. Results. On average, participants knew 3 homicide victims who were overwhelmingly peers. Participant experiences of homicide death started in early childhood, peaked in adolescence, and persisted into emerging adulthood. The traumatic loss of peer homicide was a significant developmental turning point and disrupted participants’ social networks. Conclusions. The traumatic loss of peer homicide was a prevalent life course experience for young Black men and identified the need for trauma- and grief-informed interventions. Future research is needed to examine the physical and psychosocial consequences, coping resources and strategies, and developmental implications of traumatic loss for young Black men in urban contexts. PMID:25905836

Dental development and life history in living African and Asian apes.

PubMed

Kelley, Jay; Schwartz, Gary T

2010-01-19

Life-history inference is an important aim of paleoprimatology, but life histories cannot be discerned directly from the fossil record. Among extant primates, the timing of many life-history attributes is correlated with the age at emergence of the first permanent molar (M1), which can therefore serve as a means to directly compare the life histories of fossil and extant species. To date, M1 emergence ages exist for only a small fraction of extant primate species and consist primarily of data from captive individuals, which may show accelerated dental eruption compared with free-living individuals. Data on M1 emergence ages in wild great apes exist for only a single chimpanzee individual, with data for gorillas and orangutans being anecdotal. This paucity of information limits our ability to make life-history inferences using the M1 emergence ages of extinct ape and hominin species. Here we report reliable ages at M1 emergence for the orangutan, Pongo pygmaeus (4.6 y), and the gorilla, Gorilla gorilla (3.8 y), obtained from the dental histology of wild-shot individuals in museum collections. These ages and the one reported age at M1 emergence in a free-living chimpanzee of approximately 4.0 y are highly concordant with the comparative life histories of these great apes. They are also consistent with the average age at M1 emergence in relation to the timing of life-history events in modern humans, thus confirming the utility of M1 emergence ages for life-history inference and providing a basis for making reliable life-history inferences for extinct apes and hominins.

Dental development and life history in living African and Asian apes

PubMed Central

Kelley, Jay; Schwartz, Gary T.

2009-01-01

Life-history inference is an important aim of paleoprimatology, but life histories cannot be discerned directly from the fossil record. Among extant primates, the timing of many life-history attributes is correlated with the age at emergence of the first permanent molar (M1), which can therefore serve as a means to directly compare the life histories of fossil and extant species. To date, M1 emergence ages exist for only a small fraction of extant primate species and consist primarily of data from captive individuals, which may show accelerated dental eruption compared with free-living individuals. Data on M1 emergence ages in wild great apes exist for only a single chimpanzee individual, with data for gorillas and orangutans being anecdotal. This paucity of information limits our ability to make life-history inferences using the M1 emergence ages of extinct ape and hominin species. Here we report reliable ages at M1 emergence for the orangutan, Pongo pygmaeus (4.6 y), and the gorilla, Gorilla gorilla (3.8 y), obtained from the dental histology of wild-shot individuals in museum collections. These ages and the one reported age at M1 emergence in a free-living chimpanzee of approximately 4.0 y are highly concordant with the comparative life histories of these great apes. They are also consistent with the average age at M1 emergence in relation to the timing of life-history events in modern humans, thus confirming the utility of M1 emergence ages for life-history inference and providing a basis for making reliable life-history inferences for extinct apes and hominins. PMID:20080537

The Tsimane Health and Life History Project: Integrating anthropology and biomedicine.

PubMed

Gurven, Michael; Stieglitz, Jonathan; Trumble, Benjamin; Blackwell, Aaron D; Beheim, Bret; Davis, Helen; Hooper, Paul; Kaplan, Hillard

2017-04-01

The Tsimane Health and Life History Project, an integrated bio-behavioral study of the human life course, is designed to test competing hypotheses of human life-history evolution. One aim is to understand the bidirectional connections between life history and social behavior in a high-fertility, kin-based context lacking amenities of modern urban life (e.g. sanitation, banks, electricity). Another aim is to understand how a high pathogen burden influences health and well-being during development and adulthood. A third aim addresses how modernization shapes human life histories and sociality. Here we outline the project's goals, history, and main findings since its inception in 2002. We reflect on the implications of current findings and highlight the need for more coordinated ethnographic and biomedical study of contemporary nonindustrial populations to address broad questions that can situate evolutionary anthropology in a key position within the social and life sciences. © 2017 The Authors Evolutionary Anthropology: Issues, News, and Reviews Published by Wiley Periodicals, Inc.

Integrating the pace-of-life syndrome across species, sexes and individuals: covariation of life history and personality under pesticide exposure.

PubMed

Debecker, Sara; Sanmartín-Villar, Iago; de Guinea-Luengo, Miguel; Cordero-Rivera, Adolfo; Stoks, Robby

2016-05-01

The pace-of-life syndrome (POLS) hypothesis integrates covariation of life-history traits along a fast-slow continuum and covariation of behavioural traits along a proactive-reactive personality continuum. Few studies have investigated these predicted life-history/personality associations among species and between sexes. Furthermore, whether and how contaminants interfere with POLS patterns remains unexplored. We tested for covariation patterns in life history and in behaviour, and for life-history/personality covariation among species, among individuals within species and between sexes. Moreover, we investigated whether pesticide exposure affects covariation between life history and behaviour and whether species and sexes with a faster POLS strategy have a higher sensitivity to pesticides. We reared larvae of four species of Ischnura damselflies in a common garden experiment with an insecticide treatment (chlorpyrifos absent/present) in the final instar. We measured four life-history traits (larval growth rate during the pesticide treatment, larval development time, adult mass and life span) and two behavioural traits (larval feeding activity and boldness, each before and after the pesticide treatment). At the individual level, life-history traits and behavioural traits aligned along a fast-slow and a proactive-reactive continuum, respectively. Species-specific differences in life history, with fast-lived species having a faster larval growth and development, a lower mass at emergence and a shorter life span, suggested that time constraints in the larval stage were predictably driving life-history evolution both in the larval stage and across metamorphosis in the adult stage. Across species, females were consistently more slow-lived than males, reflecting that a large body size and a long life span are generally more important for females. In contrast to the POLS hypothesis, there was only little evidence for the expected positive coupling between life-history

Narratives from within: An Arendtian Approach to Life Histories and the Writing of History

ERIC Educational Resources Information Center

Tamboukou, Maria

2010-01-01

In this paper I draw on my current research of writing a genealogy of women artists, focusing in particular on the life history of the American working-class artist, May Stevens (1924-). I am particularly interested in how an analysis of the textual and visual narratives in her work, seen in the context of her life history, can intervene in the…

The Tsimane Health and Life History Project: Integrating anthropology and biomedicine

PubMed Central

Stieglitz, Jonathan; Trumble, Benjamin; Blackwell, Aaron D.; Beheim, Bret; Davis, Helen; Hooper, Paul; Kaplan, Hillard

2017-01-01

Abstract The Tsimane Health and Life History Project, an integrated bio‐behavioral study of the human life course, is designed to test competing hypotheses of human life‐history evolution. One aim is to understand the bidirectional connections between life history and social behavior in a high‐fertility, kin‐based context lacking amenities of modern urban life (e.g. sanitation, banks, electricity). Another aim is to understand how a high pathogen burden influences health and well‐being during development and adulthood. A third aim addresses how modernization shapes human life histories and sociality. Here we outline the project's goals, history, and main findings since its inception in 2002. We reflect on the implications of current findings and highlight the need for more coordinated ethnographic and biomedical study of contemporary nonindustrial populations to address broad questions that can situate evolutionary anthropology in a key position within the social and life sciences. PMID:28429567

Psychiatric disorders and treatment among newly homeless young adults with histories of foster care.

PubMed

Thompson, Ronald G; Hasin, Deborah

2012-09-01

Although foster care placement is often preceded by stressful events such as child abuse, foster care itself often exposes children to additional severe stressors. A history of foster care, as well as the childhood abuse that often precedes it, is common among homeless young adults. This study examined whether a history of foster care was associated with psychiatric disorders, prior psychiatric counseling, prescription of psychiatric medications, and prior psychiatric hospitalization among newly homeless young adults. A consecutive sample of 423 adults aged 18 to 21 years who sought emergency shelter for the first time between October 1, 2007, and February 29, 2008, were assessed at intake. Logistic regression analyses determined the associations between foster care and any psychiatric disorder (affective, anxiety, personality, and psychotic) and psychiatric treatment. The analyses adjusted for demographic characteristics, childhood abuse, substance use, prior arrest, unemployment, lack of high school diploma, and histories of psychiatric disorders and drug abuse among biological relatives. Homeless young adults with histories of foster care were 70% more likely than those without such histories to report any psychiatric disorder. They were more than twice as likely to have received mental health counseling for a psychiatric disorder, to have been prescribed psychiatric medication, and to have been hospitalized for psychiatric problems. Histories of foster care among homeless young adults should trigger screening for psychiatric disorders to aid in the provision of treatment (counseling, medication, and hospitalization) tailored to the psychiatric needs of this highly vulnerable population.

Timing of seasonal migration in mule deer: effects of climate, plant phenology, and life-history characteristics

USGS Publications Warehouse

Monteith, Kevin L.; Bleich, Vernon C.; Stephenson, Thomas R.; Pierce, Beck M.; Conner, Mary M.; Klaver, Robert W.; Bowyer, R. Terry

2011-01-01

Phenological events of plants and animals are sensitive to climatic processes. Migration is a life-history event exhibited by most large herbivores living in seasonal environments, and is thought to occur in response to dynamics of forage and weather. Decisions regarding when to migrate, however, may be affected by differences in life-history characteristics of individuals. Long-term and intensive study of a population of mule deer (Odocoileus hemionus) in the Sierra Nevada, California, USA, allowed us to document patterns of migration during 11 years that encompassed a wide array of environmental conditions. We used two new techniques to properly account for interval-censored data and disentangle effects of broad-scale climate, local weather patterns, and plant phenology on seasonal patterns of migration, while incorporating effects of individual life-history characteristics. Timing of autumn migration varied substantially among individual deer, but was associated with the severity of winter weather, and in particular, snow depth and cold temperatures. Migratory responses to winter weather, however, were affected by age, nutritional condition, and summer residency of individual females. Old females and those in good nutritional condition risked encountering severe weather by delaying autumn migration, and were thus risk-prone with respect to the potential loss of foraging opportunities in deep snow compared with young females and those in poor nutritional condition. Females that summered on the west side of the crest of the Sierra Nevada delayed autumn migration relative to east-side females, which supports the influence of the local environment on timing of migration. In contrast, timing of spring migration was unrelated to individual life-history characteristics, was nearly twice as synchronous as autumn migration, differed among years, was related to the southern oscillation index, and was influenced by absolute snow depth and advancing phenology of plants

Impact of Life History on Fear Memory and Extinction

PubMed Central

Remmes, Jasmin; Bodden, Carina; Richter, S. Helene; Lesting, Jörg; Sachser, Norbert; Pape, Hans-Christian; Seidenbecher, Thomas

2016-01-01

Behavioral profiles are strongly shaped by an individual's whole life experience. The accumulation of negative experiences over lifetime is thought to promote anxiety-like behavior in adulthood (“allostatic load hypothesis”). In contrast, the “mismatch hypothesis” of psychiatric disease suggests that high levels of anxiety-like behavior are the result of a discrepancy between early and late environment. The aim of the present study was to investigate how different life histories shape the expression of anxiety-like behavior and modulate fear memory. In addition, we aimed to clarify which of the two hypotheses can better explain the modulation of anxiety and fear. For this purpose, male mice grew up under either adverse or beneficial conditions during early phase of life. In adulthood they were further subdivided in groups that either matched or mismatched the condition experienced before, resulting in four different life histories. The main results were: (i) Early life benefit followed by late life adversity caused decreased levels of anxiety-like behavior. (ii) Accumulation of adversity throughout life history led to impaired fear extinction learning. Late life adversity as compared to late life benefit mainly affected extinction training, while early life adversity as compared to early life benefit interfered with extinction recall. Concerning anxiety-like behavior, the results do neither support the allostatic load nor the mismatch hypothesis, but rather indicate an anxiolytic effect of a mismatched early beneficial and later adverse life history. In contrast, fear memory was strongly affected by the accumulation of adverse experiences over the lifetime, therefore supporting allostatic load hypothesis. In summary, this study highlights that anxiety-like behavior and fear memory are differently affected by specific combinations of adverse or beneficial events experienced throughout life. PMID:27757077

Selection of trilateral continuums of life history strategies under food web interactions.

PubMed

Fujiwara, Masami

2018-03-14

The study of life history strategies has a long history in ecology and evolution, but determining the underlying mechanisms driving the evolution of life history variation and its consequences for population regulation remains a major challenge. In this study, a food web model with constant environmental conditions was used to demonstrate how multi-species consumer-resource interactions (food-web interactions) can create variation in the duration of the adult stage, age of maturation, and fecundity among species. The model included three key ecological processes: size-dependent species interactions, energetics, and transition among developmental stages. Resultant patterns of life history variation were consistent with previous empirical observations of the life history strategies of aquatic organisms referred to as periodic, equilibrium, and opportunistic strategies (trilateral continuums of life history strategies). Results from the simulation model suggest that these three life history strategies can emerge from food web interactions even when abiotic environmental conditions are held constant.

Life history and ecology of the elusive European short-snouted seahorse Hippocampus hippocampus.

PubMed

Curtis, J M R; Santos, S V; Nadeau, J L; Gunn, B; Bigney Wilner, K; Balasubramanian, H; Overington, S; Lesage, C-M; D'entremont, J; Wieckowski, K

2017-12-01

To improve the understanding of the life history and ecology of one of Europe's most elusive fishes, the short-snouted seahorse Hippocampus hippocampus, data from wild populations in a shallow coastal lagoon in southern Portugal were analysed. The data were collected from 17 tagged seahorses on a focal-study grid as well as from >350 seahorses encountered during underwater visual surveys and a fishery-independent study using beach seines. These populations of settled juveniles and adults had a mean population density of 0·009 m -2 . During the study period (2000-2004), reproduction peaked in July and August. Juveniles recruited to the lagoon at c. 66 mm standard length (L S ) and 0·5 years of age and established small home ranges (0·8 to 18·2 m 2 ). First reproduction was estimated at 100 mm and 1 year of age. Based on a fitted von Bertalanffy model, H. hippocampus grew quickly (growth coefficient K = 0·93) to a maximum theoretical size L ∞  = 150 mm and have a maximum lifespan of c. 3·2 years. Courtship behaviours were consistent with the maintenance of pair bonds and males brooded multiple batches of young per year. Estimated annual reproductive output averaged 871 young (±632). Together these analyses provide the first life-history parameters for this species and indicate that H. hippocampus bears characteristics of opportunist and intermediate strategists. Such populations are predicted to exhibit large fluctuations in abundance, making them vulnerable to extended periods of poor recruitment. © 2017 The Fisheries Society of the British Isles.

Life history theory and breast cancer risk: methodological and theoretical challenges: Response to "Is estrogen receptor negative breast cancer risk associated with a fast life history strategy?".

PubMed

Aktipis, Athena

2016-01-01

In a meta-analysis published by myself and co-authors, we report differences in the life history risk factors for estrogen receptor negative (ER-) and estrogen receptor positive (ER+) breast cancers. Our meta-analysis did not find the association of ER- breast cancer risk with fast life history characteristics that Hidaka and Boddy suggest in their response to our article. There are a number of possible explanations for the differences between their conclusions and the conclusions we drew from our meta-analysis, including limitations of our meta-analysis and methodological challenges in measuring and categorizing estrogen receptor status. These challenges, along with the association of ER+ breast cancer with slow life history characteristics, may make it challenging to find a clear signal of ER- breast cancer with fast life history characteristics, even if that relationship does exist. The contradictory results regarding breast cancer risk and life history characteristics illustrate a more general challenge in evolutionary medicine: often different sub-theories in evolutionary biology make contradictory predictions about disease risk. In this case, life history models predict that breast cancer risk should increase with faster life history characteristics, while the evolutionary mismatch hypothesis predicts that breast cancer risk should increase with delayed reproduction. Whether life history tradeoffs contribute to ER- breast cancer is still an open question, but current models and several lines of evidence suggest that it is a possibility. © The Author(s) 2016. Published by Oxford University Press on behalf of the Foundation for Evolution, Medicine, and Public Health.

Grandmothering life histories and human pair bonding.

PubMed

Coxworth, James E; Kim, Peter S; McQueen, John S; Hawkes, Kristen

2015-09-22

The evolution of distinctively human life history and social organization is generally attributed to paternal provisioning based on pair bonds. Here we develop an alternative argument that connects the evolution of human pair bonds to the male-biased mating sex ratios that accompanied the evolution of human life history. We simulate an agent-based model of the grandmother hypothesis, compare simulated sex ratios to data on great apes and human hunter-gatherers, and note associations between a preponderance of males and mate guarding across taxa. Then we explore a recent model that highlights the importance of mating sex ratios for differences between birds and mammals and conclude that lessons for human evolution cannot ignore mammalian reproductive constraints. In contradiction to our claim that male-biased sex ratios are characteristically human, female-biased ratios are reported in some populations. We consider the likelihood that fertile men are undercounted and conclude that the mate-guarding hypothesis for human pair bonds gains strength from explicit links with our grandmothering life history.

Life histories predict coral community disassembly under multiple stressors.

PubMed

Darling, Emily S; McClanahan, Timothy R; Côté, Isabelle M

2013-06-01

Climate change is reshaping biological communities against a background of existing human pressure. Evaluating the impacts of multiple stressors on community dynamics can be particularly challenging in species-rich ecosystems, such as coral reefs. Here, we investigate whether life-history strategies and cotolerance to different stressors can predict community responses to fishing and temperature-driven bleaching using a 20-year time series of coral assemblages in Kenya. We found that the initial life-history composition of coral taxa largely determined the impacts of bleaching and coral loss. Prior to the 1998 bleaching event, coral assemblages within no-take marine reserves were composed of three distinct life histories - competitive, stress-tolerant and weedy- and exhibited strong declines following bleaching with limited subsequent recovery. In contrast, fished reefs had lower coral cover, fewer genera and were composed of stress-tolerant and weedy corals that were less affected by bleaching over the long term. Despite these general patterns, we found limited evidence for cotolerance as coral genera and life histories were variable in their sensitivities to fishing and bleaching. Overall, fishing and bleaching have reduced coral diversity and led to altered coral communities of 'survivor' species with stress-tolerant and weedy life histories. Our findings are consistent with expectations that climate change interacting with existing human pressure will result in the loss of coral diversity and critical reef habitat. © 2013 Blackwell Publishing Ltd.

Life-history evolution in ants: the case of Cardiocondyla

PubMed Central

2017-01-01

Ants are important components of most terrestrial habitats, and a better knowledge of the diversity of their life histories is essential to understand many aspects of ecosystem functioning. The myrmicine genus Cardiocondyla shows a wide range of colony structures, reproductive behaviours, queen and male lifespans, and habitat use. Reconstructing the evolutionary pathways of individual and social phenotypic traits suggests that the ancestral life history of Cardiocondyla was characterized by the presence of multiple, short-lived queens in small-sized colonies and a male polyphenism with winged dispersers and wingless fighters, which engage in lethal combat over female sexuals within their natal nests. Single queening, queen polyphenism, the loss of winged males and tolerance among wingless males appear to be derived traits that evolved with changes in nesting habits, colony size and the spread from tropical to seasonal environments. The aim of this review is to bring together the information on life-history evolution in Cardiocondyla and to highlight the suitability of this genus for functional genomic studies of adaptation, phenotypic plasticity, senescence, invasiveness and other key life-history traits of ants. PMID:28298341

Mammalian brain development and our grandmothering life history.

PubMed

Hawkes, Kristen; Finlay, Barbara L

2018-05-02

Among mammals, including humans, adult brain size and the relative size of brain components depend precisely on the duration of a highly regular process of neural development. Much wider variation is seen in rates of body growth and the state of neural maturation at life history events like birth and weaning. Large brains result from slow maturation, which in humans is accompanied by weaning early with respect to both neural maturation and longevity. The grandmother hypothesis proposes this distinctive combination of life history features evolved as ancestral populations began to depend on foods that just weaned juveniles couldn't handle. Here we trace possible reciprocal connections between brain development and life history, highlighting the resulting extended neural plasticity in a wider cognitive ecology of allomaternal care that distinguishes human ontogeny with consequences for other peculiarities of our lineage. Copyright © 2018 Elsevier Inc. All rights reserved.

The Genetic Architecture Underlying the Evolution of a Rare Piscivorous Life History Form in Brown Trout after Secondary Contact and Strong Introgression.

PubMed

Jacobs, Arne; Hughes, Martin R; Robinson, Paige C; Adams, Colin E; Elmer, Kathryn R

2018-05-31

Identifying the genetic basis underlying phenotypic divergence and reproductive isolation is a longstanding problem in evolutionary biology. Genetic signals of adaptation and reproductive isolation are often confounded by a wide range of factors, such as variation in demographic history or genomic features. Brown trout ( Salmo trutta ) in the Loch Maree catchment, Scotland, exhibit reproductively isolated divergent life history morphs, including a rare piscivorous (ferox) life history form displaying larger body size, greater longevity and delayed maturation compared to sympatric benthivorous brown trout. Using a dataset of 16,066 SNPs, we analyzed the evolutionary history and genetic architecture underlying this divergence. We found that ferox trout and benthivorous brown trout most likely evolved after recent secondary contact of two distinct glacial lineages, and identified 33 genomic outlier windows across the genome, of which several have most likely formed through selection. We further identified twelve candidate genes and biological pathways related to growth, development and immune response potentially underpinning the observed phenotypic differences. The identification of clear genomic signals divergent between life history phenotypes and potentially linked to reproductive isolation, through size assortative mating, as well as the identification of the underlying demographic history, highlights the power of genomic studies of young species pairs for understanding the factors shaping genetic differentiation.

Does life history predict risk-taking behavior of wintering dabbling ducks?

USGS Publications Warehouse

Ackerman, Joshua T.; Eadie, J.M.; Moore, T.G.

2006-01-01

Life-history theory predicts that longer-lived, less fecund species should take fewer risks when exposed to predation than shorter-lived, more fecund species. We tested this prediction for seven species of dabbling ducks (Anas) by measuring the approach behavior (behavior of ducks when approaching potential landing sites) of 1099 duck flocks during 37 hunting trials and 491 flocks during 13 trials conducted immediately after the 1999-2000 waterfowl hunting season in California, USA. We also experimentally manipulated the attractiveness of the study site by using two decoy treatments: (1) traditional, stationary decoys only, and (2) traditional decoys in conjunction with a mechanical spinning-wing decoy. Approach behavior of ducks was strongly correlated with their life history. Minimum approach distance was negatively correlated with reproductive output during each decoy treatment and trial type. Similarly, the proportion of flocks taking risk (approaching landing sites to within 45 m) was positively correlated with reproductive output. We found similar patterns of approach behavior in relation to other life-history parameters (i.e., adult female body mass and annual adult female survival rate). Thus, species characterized by a slower life-history strategy (e.g., Northern Pintail [A. acuta]) were more risk-averse than species with a faster life-history strategy (e.g., Cinnamon Teal [A. cyanoptera]). Furthermore, although we were able to reduce risk-averseness using the spinning-wing decoy, we were unable to override the influence of life history on risk-taking behavior. Alternative explanations did not account for the observed correlation between approach behavior and life-history parameters. These results suggest that life history influences the risk-taking behavior of dabbling ducks and provide an explanation for the differential vulnerability of waterfowl to harvest. ?? The Cooper Ornithological Society 2006.

Sprecies profiles: Life histories and environmental requirements of coastal fishes and invertebrates (Mid-Atlantic): Bluefish

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

Pottern, G.B.; Huish, M.T.; Kerby, J.H.

1989-02-01

Species profiles are literature summaries of the taxonomy, morphology, distribution, life history, and environmental requirements of coastal fishes and invertebrates within a specified range. They are written to assist in environmental impact assessment and decision making by coastal planners and developers. Bluefish are the most important recreational fish in the United States, especially in the mid-Atlantic region. The commercial catch is smaller but has increased during recent years. One population spawns offshore during spring from northern Florida to North Carolina, and these young migrate into mid-Atlantic coastal waters to spend their summer and fall. A second population spawns offshore duringmore » summer from North Carolina to Massachusetts, but most of these young remain offshore for the remainder of the season. In late fall, young and adults of both populations migrate south until the following spring. Bluefish are migratory, opportunistic, pelagic predators throughout life, and their seasonal abundance may have profound community structuring effects. Schools of juvenile bluefish may be important forage for many pelagic predators, including adults of their own species. Photoperiod apparently triggers long-range migration, and temperature serves as a proximal cue to short-range migration. Bluefish are sensitive to bacterial infection in polluted water and have little tolerance for low oxygen conditions. 55 refs., 6 figs., 3 tabs.« less

Late-life and life history predictors of older adults' high-risk alcohol consumption and drinking problems.

PubMed

Moos, Rudolf H; Schutte, Kathleen K; Brennan, Penny L; Moos, Bernice S

2010-04-01

This prospective, longitudinal study focused on late-life and life history predictors of high-risk alcohol consumption and drinking problems during a 20-year interval as adults matured from age 55-65 to 75-85. A sample of older community residents (N=719) who had consumed alcohol in the past year or shortly before was surveyed at baseline and 10 and 20 years later. At each contact point, participants completed an inventory that assessed their alcohol consumption, drinking problems, and personal and life context factors. Participants also provided information about their life history of drinking and help-seeking. Older adults who, at baseline, had more friends who approved of drinking, relied on substances for tension reduction, and had more financial resources were more likely to engage in high-risk alcohol consumption and to incur drinking problems at 10- and 20-year follow-ups. With respect to life history factors, drinking problems by age 50 were associated with a higher likelihood of late-life high-risk alcohol consumption and drinking problems; having tried to cut down on drinking and participation in Alcoholics Anonymous were associated with a lower likelihood of high-risk consumption and problems. Specific late-life and life history factors can identify older adults likely to engage in excessive alcohol consumption 10 and 20 years later. Targeted screening that considers current alcohol consumption and life context, and history of drinking problems and help-seeking, could help identify older adults at higher risk for excessive or problematic drinking. Published by Elsevier Ireland Ltd.

The life-history basis of behavioural innovations

PubMed Central

Sol, Daniel; Sayol, Ferran; Ducatez, Simon; Lefebvre, Louis

2016-01-01

The evolutionary origin of innovativeness remains puzzling because innovating means responding to novel or unusual problems and hence is unlikely to be selected by itself. A plausible alternative is considering innovativeness as a co-opted product of traits that have evolved for other functions yet together predispose individuals to solve problems by adopting novel behaviours. However, this raises the question of why these adaptations should evolve together in an animal. Here, we develop the argument that the adaptations enabling animals to innovate evolve together because they are jointly part of a life-history strategy for coping with environmental changes. In support of this claim, we present comparative evidence showing that in birds, (i) innovative propensity is linked to life histories that prioritize future over current reproduction, (ii) the link is in part explained by differences in brain size, and (iii) innovative propensity and life-history traits may evolve together in generalist species that frequently expose themselves to novel or unusual conditions. Combined with previous evidence, these findings suggest that innovativeness is not a specialized adaptation but more likely part of a broader general adaptive system to cope with changes in the environment. PMID:26926277

Life history theory predicts fish assemblage response to hydrologic regimes.

PubMed

Mims, Meryl C; Olden, Julian D

2012-01-01

The hydrologic regime is regarded as the primary driver of freshwater ecosystems, structuring the physical habitat template, providing connectivity, framing biotic interactions, and ultimately selecting for specific life histories of aquatic organisms. In the present study, we tested ecological theory predicting directional relationships between major dimensions of the flow regime and life history composition of fish assemblages in perennial free-flowing rivers throughout the continental United States. Using long-term discharge records and fish trait and survey data for 109 stream locations, we found that 11 out of 18 relationships (61%) tested between the three life history strategies (opportunistic, periodic, and equilibrium) and six hydrologic metrics (two each describing flow variability, predictability, and seasonality) were statistically significant (P < or = 0.05) according to quantile regression. Our results largely support a priori hypotheses of relationships between specific flow indices and relative prevalence of fish life history strategies, with 82% of all significant relationships observed supporting predictions from life history theory. Specifically, we found that (1) opportunistic strategists were positively related to measures of flow variability and negatively related to predictability and seasonality, (2) periodic strategists were positively related to high flow seasonality and negatively related to variability, and (3) the equilibrium strategists were negatively related to flow variability and positively related to predictability. Our study provides important empirical evidence illustrating the value of using life history theory to understand both the patterns and processes by which fish assemblage structure is shaped by adaptation to natural regimes of variability, predictability, and seasonality of critical flow events over broad biogeographic scales.

Robin's Story: Life History of an Exemplary American Female Physical Education Teacher

ERIC Educational Resources Information Center

Cazers, Gunars; Curtner-Smith, Matthew D.

2017-01-01

Purpose: The purpose was to construct the life history of Robin, an exemplary female physical educator, to hear her voice, and to explore ways in which she experienced marginalization. Few life histories of exemplary physical educators have been recounted. Method: Robin's life history was investigated in light of the theory of occupational…

Metabolic syndrome and parental history of cardiovascular disease in young adults in urban Ghana.

PubMed

Yeboah, Kwame; Dodam, Kennedy Konlan; Affrim, Patrick Kormla; Adu-Gyamfi, Linda; Bado, Anormah Rashid; Owusu Mensah, Richard N A; Adjei, Afua Bontu; Gyan, Ben

2017-08-03

Metabolic syndrome (MetS) in young adults poses significant cardiovascular diseases (CVD) risk for later years. Parental history of CVDs is known to affect the prevalence of CVD risk in adulthood. In sub-Saharan Africa, the burden of MetS in young adults and its relationship with parental CVDs is largely unknown. We studied the gender-specific prevalence of MetS and its association with parental history of diabetes, hypertension and CVDs in young adults resident in urban Ghana. In a cross-sectional design, 364 young adults aged 20-30 years were randomly recruited from students of University of Ghana. A structured questionnaire was used to collect data on demography, lifestyle, medical and parental medical history. Anthropometric indices and blood pressures were measured. Fasting blood samples were collected to measure plasma levels of glucose, lipid profile, urea and creatinine. MetS was defined according to the Joint Scientific Statement criteria. The prevalence of MetS was 12.4%, higher in females than male participants (18.4% vs 5.7, p = 0.019). Female participants had higher levels of all the components of MetS than the male participants. Compared to participants with no history of parental CVDs, participants with parental CVDs had a higher proportion of abdominal obesity. A positive history of parental CVDs was associated with increase in odds of MetS [OR (95% CI): 1.23 (1.12-3.04), p = 0.037]. In our study population, there is relatively high prevalence of MetS; higher in females compared to male participants. Parental history of CVDs was associated with MetS.

Litter sex composition affects life-history traits in yellow-bellied marmots.

PubMed

Monclús, Raquel; Blumstein, Daniel T

2012-01-01

1. The presence of siblings might have long-lasting fitness consequences because they influence the early environment in which an animal develops. Several studies under laboratory conditions have shown long-lasting consequences from the presence of male siblings in utero on morphology and life-history traits. However, in wild animals, such effects of litter sex composition are unexplored. 2. We capitalized on a long-term study of individually marked yellow-bellied marmots (Marmota flaviventris) and documented the effects of weaned litter sex composition and anogenital distance on several life-history and fitness traits. 3. First, we demonstrated that the number of males in a litter influenced anogenital distance. Then, we found that masculinized females, those with larger anogenital distances, were less likely to survive their first hibernation, were more likely to disperse and were less likely to become pregnant and wean young. Males from male-biased litters had lower growth rates, but we failed to detect longer-term consequences. 4. Taken together, our results show profound sex-dependent effects of litter sex composition, probably due to differential prenatal exposure to androgens, in free-living animals. We conclude that masculinization might constitute an alternative mechanism explaining variation in different demographic traits. This finding highlights the importance of studying these maternal effects, and they enhance our concern over the widespread use of endocrine disrupting compounds. © 2011 The Authors. Journal of Animal Ecology © 2011 British Ecological Society.

Extraordinarily rapid life-history divergence between Cryptasterina sea star species.

PubMed

Puritz, Jonathan B; Keever, Carson C; Addison, Jason A; Byrne, Maria; Hart, Michael W; Grosberg, Richard K; Toonen, Robert J

2012-10-07

Life history plays a critical role in governing microevolutionary processes such as gene flow and adaptation, as well as macroevolutionary processes such speciation. Here, we use multilocus phylogeographic analyses to examine a speciation event involving spectacular life-history differences between sister species of sea stars. Cryptasterina hystera has evolved a suite of derived life-history traits (including internal self-fertilization and brood protection) that differ from its sister species Cryptasterina pentagona, a gonochoric broadcast spawner. We show that these species have only been reproductively isolated for approximately 6000 years (95% highest posterior density of 905-22 628), and that this life-history change may be responsible for dramatic genetic consequences, including low nucleotide diversity, zero heterozygosity and no gene flow. The rapid divergence of these species rules out some mechanisms of isolation such as adaptation to microhabitats in sympatry, or slow divergence by genetic drift during prolonged isolation. We hypothesize that the large phenotypic differences between species relative to the short divergence time suggests that the life-history differences observed may be direct responses to disruptive selection between populations. We speculate that local environmental or demographic differences at the southern range margin are possible mechanisms of selection driving one of the fastest known marine speciation events.

Talking (or not) about family health history in families of Latino young adults.

PubMed

Corona, Rosalie; Rodríguez, Vivian; Quillin, John; Gyure, Maria; Bodurtha, Joann

2013-10-01

Although individuals recognize the importance of knowing their family's health history for their own health, relatively few people (e.g., less than a third in one national survey) collect this type of information. This study examines the rates of family communication about family health history of cancer, and predictors of communication in a sample of English-speaking Latino young adults. A total of 224 Latino young adults completed a survey that included measures on family communication, cultural factors, religious commitment, and cancer worry. We found that few Latino young adults reported collecting information from their families for the purposes of creating a family health history (18%) or sharing information about hereditary cancer risk with family members (16%). In contrast, slightly more than half of the participants reported generally "talking with their mothers about their family's health history of cancer." Logistic regression results indicated that cancer worry (odds ratio [OR] = 2.31; 95% confidence interval [CI] = 1.08-4.93), being female (OR = 3.12; 95% CI = 1.02-8.08), and being older (OR = 1.33; 95% CI = 1.01-1.76) were associated with increased rates of collecting information from family members. In contrast, orientation to the Latino culture (OR = 2.81; 95% CI = 1.33-5.94) and religious commitment (OR = 1.54; 95% CI = 1.02-2.32) were associated with increased rates of giving cancer information. Results highlight the need for prevention programs to help further general discussions about a family's history of cancer to more specific information related to family health history.

How Life History Can Sway the Fixation Probability of Mutants

PubMed Central

Li, Xiang-Yi; Kurokawa, Shun; Giaimo, Stefano; Traulsen, Arne

2016-01-01

In this work, we study the effects of demographic structure on evolutionary dynamics when selection acts on reproduction, survival, or both. In contrast to the previously discovered pattern that the fixation probability of a neutral mutant decreases while the population becomes younger, we show that a mutant with a constant selective advantage may have a maximum or a minimum of the fixation probability in populations with an intermediate fraction of young individuals. This highlights the importance of life history and demographic structure in studying evolutionary dynamics. We also illustrate the fundamental differences between selection on reproduction and selection on survival when age structure is present. In addition, we evaluate the relative importance of size and structure of the population in determining the fixation probability of the mutant. Our work lays the foundation for also studying density- and frequency-dependent effects in populations when demographic structures cannot be neglected. PMID:27129737

Education and employment outcomes of young adults with a history of developmental language disorder

PubMed Central

Durkin, Kevin; Toseeb, Umar; Botting, Nicola; Pickles, Andrew

2017-01-01

Abstract Background Developmental language disorder (DLD) presents a considerable barrier for young adults to engage in further education and training. Early studies with young adults with DLD revealed poor educational achievement and lack of opportunities to progress in education. More recent studies have provided more positive findings. Relatively sparse data exist, however, on current cohorts and the factors that predict outcomes. Aims To examine educational and employment outcomes in young adulthood in a sample of people with histories of DLD compared with an age‐matched peer group without DLD. We ask: How do educational pathways and early jobs compare between those with and without DLD? Are young adults with DLD receiving similar levels of income as their peers? To what extent are language and literacy abilities associated with outcomes? Methods & Procedures Participants included 84 individuals with DLD (67% males) and 88 age‐matched peers without DLD (56% males). Participants were on average 24 years of age. They completed a battery of psycholinguistic, literacy and nonverbal skills assessments. Data were also collected on educational qualifications, current educational status, extent of educational support received, employment status, history and support, as well as current income. Outcomes & Results Those with DLD obtained lower academic and vocational qualifications. Higher educational/vocational qualifications were associated with better language, better reading and higher performance IQ (PIQ). There were few differences between the two groups in terms of engagement with education, but the mean age at leaving education was significantly earlier in the participants with DLD. Substantially more participants with DLD reported receiving support or dispensation from their educational institution. There was no significant difference between groups in the proportion of young people currently employed, though a higher proportion of the age‐matched peers was

Education and employment outcomes of young adults with a history of developmental language disorder.

PubMed

Conti-Ramsden, Gina; Durkin, Kevin; Toseeb, Umar; Botting, Nicola; Pickles, Andrew

2018-03-01

Developmental language disorder (DLD) presents a considerable barrier for young adults to engage in further education and training. Early studies with young adults with DLD revealed poor educational achievement and lack of opportunities to progress in education. More recent studies have provided more positive findings. Relatively sparse data exist, however, on current cohorts and the factors that predict outcomes. To examine educational and employment outcomes in young adulthood in a sample of people with histories of DLD compared with an age-matched peer group without DLD. We ask: How do educational pathways and early jobs compare between those with and without DLD? Are young adults with DLD receiving similar levels of income as their peers? To what extent are language and literacy abilities associated with outcomes? Participants included 84 individuals with DLD (67% males) and 88 age-matched peers without DLD (56% males). Participants were on average 24 years of age. They completed a battery of psycholinguistic, literacy and nonverbal skills assessments. Data were also collected on educational qualifications, current educational status, extent of educational support received, employment status, history and support, as well as current income. Those with DLD obtained lower academic and vocational qualifications. Higher educational/vocational qualifications were associated with better language, better reading and higher performance IQ (PIQ). There were few differences between the two groups in terms of engagement with education, but the mean age at leaving education was significantly earlier in the participants with DLD. Substantially more participants with DLD reported receiving support or dispensation from their educational institution. There was no significant difference between groups in the proportion of young people currently employed, though a higher proportion of the age-matched peers was in work full time. Participants with DLD were much more likely to be

Factors associated with young adults' knowledge regarding family history of Stroke 1

PubMed Central

Lima, Maria Jose Melo Ramos; Moreira, Thereza Maria Magalhães; Florêncio, Raquel Sampaio; Braga, Predro

2016-01-01

ABSTRACT Objective: to analyze the factors associated with young adults' knowledge regarding family history of stroke. Method: an analytical transversal study, with 579 young adults from state schools, with collection of sociodemographic, clinical and risk factor-related variables, analyzed using logistic regression (backward elimination). Results: a statistical association was detected between age, civil status, and classification of arterial blood pressure and abdominal circumference with knowledge of family history of stroke. In the final logistic regression model, a statistical association was observed between knowledge regarding family history of stroke and the civil status of having a partner (ORa=1.61[1.07-2.42]; p=0.023), abdominal circumference (ORa=0.98[0.96-0.99]; p=0.012) and normal arterial blood pressure (ORa=2.56[1.19-5.52]; p=0.016). Conclusion: an association was observed between socioeconomic factors and risk factors for stroke and knowledge of family history of stroke, suggesting the need for health education or even educational programs on this topic for the clientele in question. PMID:27878217

Healthy Behaviors and Lifestyles in Young Adults with a History of Developmental Disabilities

ERIC Educational Resources Information Center

Rurangirwa, Jacqueline; Braun, Kim Van Naarden; Schendel, Diana; Yeargin-Allsopp, Marshalyn

2006-01-01

Objective: Measure select Healthy People 2010 Leading Health Indicators in young adults with and without a history of developmental disabilities (DD) using a population-based cohort. Methods: Young adults were interviewed to assess the prevalence of seven Leading Health Indicators: physical activity, overweight and obesity, tobacco use, substance…

To Fairly Tell: Social Mobility, Life Histories, and the Anthropologist

ERIC Educational Resources Information Center

Benei, Veronique

2010-01-01

This article focuses on social agents' own understandings of socio-economic mobility and social achievement, exploring the possibilities offered by the tool of "family" life history in the context of formerly Untouchable communities in western India, Maharashtra. While arguing in favour of family life histories as both resource and…

Inadvertent Exemplars: Life History Portraits of Two Socially Just Principals

ERIC Educational Resources Information Center

Scanlan, Martin

2012-01-01

This study creates life history portraits of two White middle-class native-English-speaking principals demonstrating commitments to social justice in their work in public elementary schools serving disproportionately high populations of students who are marginalized by poverty, race, and linguistic heritage. Through self-reported life histories of…

Assessing the quality of life history information in publicly available databases.

PubMed

Thorson, James T; Cope, Jason M; Patrick, Wesley S

2014-01-01

Single-species life history parameters are central to ecological research and management, including the fields of macro-ecology, fisheries science, and ecosystem modeling. However, there has been little independent evaluation of the precision and accuracy of the life history values in global and publicly available databases. We therefore develop a novel method based on a Bayesian errors-in-variables model that compares database entries with estimates from local experts, and we illustrate this process by assessing the accuracy and precision of entries in FishBase, one of the largest and oldest life history databases. This model distinguishes biases among seven life history parameters, two types of information available in FishBase (i.e., published values and those estimated from other parameters), and two taxa (i.e., bony and cartilaginous fishes) relative to values from regional experts in the United States, while accounting for additional variance caused by sex- and region-specific life history traits. For published values in FishBase, the model identifies a small positive bias in natural mortality and negative bias in maximum age, perhaps caused by unacknowledged mortality caused by fishing. For life history values calculated by FishBase, the model identified large and inconsistent biases. The model also demonstrates greatest precision for body size parameters, decreased precision for values derived from geographically distant populations, and greatest between-sex differences in age at maturity. We recommend that our bias and precision estimates be used in future errors-in-variables models as a prior on measurement errors. This approach is broadly applicable to global databases of life history traits and, if used, will encourage further development and improvements in these databases.

ELASTICITY ANALYSIS OF AMPHIBIAN LIFE HISTORIES

EPA Science Inventory

By comparing life history parameters (e.g., age at metamorphosis, age at sexual maturation, egg number, longevity) and phenology of different species, we gain valuable insight into why growth rates differ across populations. Although the demography of most amphibians is lacking, ...

Reflections on the Life Histories of Today's LGBQ Postsecondary Students

ERIC Educational Resources Information Center

Olive, James L.

2012-01-01

This qualitative multiple-case study utilized a life history methodology in which written and oral narratives were obtained from six postsecondary students who self-identified as lesbian, gay, bisexual, and/or queer (LGBQ). Through the construction of life histories, the researcher endeavored to understand how past experiences and behaviors shaped…

Using Art to Teach History to Young Learners

ERIC Educational Resources Information Center

Christensen, Lois McFadyen

2006-01-01

This article describes how using authentic artwork, such as that of Bernice Sims, as an instructional strategy can help young learners inquire about historical events. The accompanying lesson illustrates how to use Sims's works and life experiences to gain new perspectives and a greater understanding of the civil rights movement and social justice…

Life history strategy of the honey bee, Apis mellifera.

PubMed

Seeley, Thomas D

1978-01-01

The feral honey bee queens (colonies) of central New York State (USA) show a K-type life history strategy. Their demographic characteristics include low early life mortality, low reproductive rate, long lifespan, high population stability and repeated reproductions. Identifying the life history strategy of these bees reveals the general pattern of selection for competitive ability, rather than productivity, which has shaped their societies. Selection for competitive power explains the adaptiveness (compared with alternatives found in many other insect societies) of the large perennial colonies, infrequent but expensive offspring, and efficient foraging which characterize the social organization of these bees.

Late-Life and Life History Predictors of Older Adults of High-Risk Alcohol Consumption and Drinking Problems

PubMed Central

Moos, Rudolf H.; Schutte, Kathleen K.; Brennan, Penny L.; Moos, Bernice S.

2009-01-01

Aims This prospective, longitudinal study focused on late-life and life history predictors of high-risk alcohol consumption and drinking problems during a 20-year interval as adults matured from age 55–65 to age 75–85. Design, Setting, Participants A sample of older community residents (N=719) who had consumed alcohol in the past year or shortly before was surveyed at baseline and 10 years and 20 years later. Measurements At each contact point, participants completed an inventory that assessed their alcohol consumption, drinking problems, and personal and life context factors. Participants also provided information about their life history of drinking and help-seeking. Results Older adults who, at baseline, had more friends who approved of drinking, relied on substances for tension reduction, and had more financial resources were more likely to engage in high-risk alcohol consumption and to incur drinking problems at 10-year and 20-year follow-ups. With respect to life history factors, drinking problems by age 50 were associated with a higher likelihood of late-life high-risk alcohol consumption and drinking problems; having tried to cut down on drinking and participation in Alcoholics Anonymous were associated with a lower likelihood of high-risk consumption and problems. Conclusion Specific late-life and life history factors can identify older adults likely to engage in excessive alcohol consumption 10 and 20 years later. Targeted screening that considers current alcohol consumption and life context, and history of drinking problems and help-seeking, could help identify older adults at higher risk for excessive or problematic drinking. PMID:19969428

Ovipositor morphology correlates with life history evolution in agaonid fig wasps

NASA Astrophysics Data System (ADS)

Elias, Larissa Galante; Kjellberg, Finn; Farache, Fernando Henrique Antoniolli; Almeida, Eduardo A. B.; Rasplus, Jean-Yves; Cruaud, Astrid; Peng, Yan-Qiong; Yang, Da-Rong; Pereira, Rodrigo Augusto Santinelo

2018-07-01

The high adaptive success of parasitic Hymenoptera might be related to the use of different oviposition sites, allowing niche partitioning among co-occurring species resulting in life history specialization and diversification. In this scenario, evolutionary changes in life history and resources for oviposition can be associated with changes in ovipositor structure, allowing exploitation of different substrates for oviposition. We used a formal phylogenetic framework to investigate the evolution of ovipositor morphology and life history in agaonid wasps. We sampled 24 species with different life histories belonging to all main clades of Agaonidae including representatives of all described genera of non-pollinating fig wasps (NPFW). Our results show an overall correlation between ovipositor morphology and life history in agaonid fig wasps. Ovipositor morphologies seem to be related to constraints imposed by features of the oviposition sites since ovipositor morphology has experienced convergent evolution at least four times in Sycophaginae (Agaonidae) according to the resource used. Non-galling species have more distantly spaced teeth with uneven spacing, as opposed to the observed morphology of galling species. Our results suggest that the ancestral condition for ovipositor morphology was most likely the presence of one or two apical teeth. Regarding life history, ovary galling species that oviposit in receptive figs possibly represent the ancestral condition. Different ovipositor characteristics allow exploitation of new niches and may be related to resource partitioning and species co-existence in the fig-fig wasp system.

Material security, life history, and moralistic religions: A cross-cultural examination.

PubMed

Purzycki, Benjamin Grant; Ross, Cody T; Apicella, Coren; Atkinson, Quentin D; Cohen, Emma; McNamara, Rita Anne; Willard, Aiyana K; Xygalatas, Dimitris; Norenzayan, Ara; Henrich, Joseph

2018-01-01

Researchers have recently proposed that "moralistic" religions-those with moral doctrines, moralistic supernatural punishment, and lower emphasis on ritual-emerged as an effect of greater wealth and material security. One interpretation appeals to life history theory, predicting that individuals with "slow life history" strategies will be more attracted to moralistic traditions as a means to judge those with "fast life history" strategies. As we had reservations about the validity of this application of life history theory, we tested these predictions with a data set consisting of 592 individuals from eight diverse societies. Our sample includes individuals from a wide range of traditions, including world religions such as Buddhism, Hinduism and Christianity, but also local traditions rooted in beliefs in animism, ancestor worship, and worship of spirits associated with nature. We first test for the presence of associations between material security, years of formal education, and reproductive success. Consistent with popular life history predictions, we find evidence that material security and education are associated with reduced reproduction. Building on this, we then test whether or not these demographic factors predict the moral concern, punitiveness, attributed knowledge-breadth, and frequency of ritual devotions towards two deities in each society. Here, we find no reliable evidence of a relationship between number of children, material security, or formal education and the individual-level religious beliefs and behaviors. We conclude with a discussion of why life-history theory is an inadequate interpretation for the emergence of factors typifying the moralistic traditions.

Life history strategies of fish species and biodiversity in eastern USA streams

USGS Publications Warehouse

Meador, Michael R.; Brown, Larry M.

2015-01-01

Predictive models have been used to determine fish species that occur less frequently than expected (decreasers) and those that occur more frequently than expected (increasers) in streams in the eastern U.S. Coupling life history traits with 51 decreaser and 38 increaser fish species provided the opportunity to examine potential mechanisms associated with predicted changes in fish species distributions in eastern streams. We assigned six life history traits – fecundity, longevity, maturation age, maximum total length, parental care, and spawning season duration – to each fish species. Decreaser species were significantly smaller in size and shorter-lived with reduced fecundity and shorter spawning seasons compared to increaser species. Cluster analysis of traits revealed correspondence with a life history model defining equilibrium (low fecundity, high parental care), opportunistic (early maturation, low parental care), and periodic (late maturation, high fecundity, low parental care) end-point strategies. Nearly 50 % of decreaser species were associated with an intermediate opportunistic-periodic strategy, suggesting that abiotic factors such as habitat specialization and streamflow alteration may serve as important influences on life history traits and strategies of decreaser species. In contrast, the percent of increaser species among life history strategy groups ranged from 21 to 32 %, suggesting that life history strategies of increaser species were more diverse than those of decreaser species. This study highlights the utility of linking life history theory to biodiversity to better understand mechanisms that contribute to fish species distributions in the eastern U.S.

Life history determines genetic structure and evolutionary potential of host-parasite interactions.

PubMed

Barrett, Luke G; Thrall, Peter H; Burdon, Jeremy J; Linde, Celeste C

2008-12-01

Measures of population genetic structure and diversity of disease-causing organisms are commonly used to draw inferences regarding their evolutionary history and potential to generate new variation in traits that determine interactions with their hosts. Parasite species exhibit a range of population structures and life-history strategies, including different transmission modes, life-cycle complexity, off-host survival mechanisms and dispersal ability. These are important determinants of the frequency and predictability of interactions with host species. Yet the complex causal relationships between spatial structure, life history and the evolutionary dynamics of parasite populations are not well understood. We demonstrate that a clear picture of the evolutionary potential of parasitic organisms and their demographic and evolutionary histories can only come from understanding the role of life history and spatial structure in influencing population dynamics and epidemiological patterns.

A trait-based framework to understand life history of mycorrhizal fungi.

PubMed

Chagnon, Pierre-Luc; Bradley, Robert L; Maherali, Hafiz; Klironomos, John N

2013-09-01

Despite the growing appreciation for the functional diversity of arbuscular mycorrhizal (AM) fungi, our understanding of the causes and consequences of this diversity is still poor. In this opinion article, we review published data on AM fungal functional traits and attempt to identify major axes of life history variation. We propose that a life history classification system based on the grouping of functional traits, such as Grime's C-S-R (competitor, stress tolerator, ruderal) framework, can help to explain life history diversification in AM fungi, successional dynamics, and the spatial structure of AM fungal assemblages. Using a common life history classification framework for both plants and AM fungi could also help in predicting probable species associations in natural communities and increase our fundamental understanding of the interaction between land plants and AM fungi. Copyright © 2013 Elsevier Ltd. All rights reserved.

The Digital Life History Project: Intergenerational Collaborative Research

ERIC Educational Resources Information Center

Loe, Meika

2013-01-01

This article describes the Digital Life History Project, a 10-week "lab" linked to a course on aging, in which students and community-dwelling elders work together to create a short digital story honoring the elder's life. After two interview sessions, the pair works together to produce a 3- to 5-minute digital life story narrated by the elder.…

Stressful life events and depressive symptoms in mothers and fathers of young children.

PubMed

Flouri, Eirini; Narayanan, Martina K; Nærde, Ane

2018-04-01

Parents of young children generally report more depressive symptoms than parents of adult children or people without children, mainly because the presence of young children increases exposure to significant stressors (such as stressful life events). However, most studies on the depressogenic role of stressful life events in parents of young children have focussed on mothers. Using data from 1138 families with young children in Norway, we investigated gender differences in the effect of stressful life events after a child's birth on the development of parental depressive symptoms in 3 follow-ups at child's ages 3-6 years. We also explored if gender differences in disposition (personality) may explain any gender differences in the depressogenic effect of life events. Nesting parents within families, we found a female gender bias for both neuroticism and depressive symptoms but no gender difference in the number of life events reported. Importantly, the number of stressful life events predicted the level and course of depressive symptoms similarly for mothers and fathers. Personality traits did not change the association between stressful life events and depressive symptoms in either mothers or fathers. Given the study design, causality cannot be inferred. There was no gender difference in the depressogenic effect of stressful life events in our sample. There was no evidence for a female dispositional sensitivity to the depressogenic effect of stressful life events, either. Stressful life events put both mothers and fathers of young children at risk of depression. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

The combined effects of parental divorce and parental history of depression on cannabis use in young adults in France.

PubMed

Sakyi, Kwame S; Melchior, Maria; Chollet, Aude; Surkan, Pamela J

2012-11-01

The joint effects of multiple social risk factors on substance use, such as parental divorce and parental history of depression, have rarely been studied in young adult offspring. We examined the combined effects of parental divorce and parental history of depression on current cannabis use among a community sample of young adults in France. Parental divorce was ascertained as divorce or separation before 2009. Parental history of depression based on parental reports of depression (1989-2009) and offspring reports of parental lifetime history of depression. Current cannabis use was defined as use at least once in the preceding 12 months. Data were analyzed using multiple logistic regression models controlling for young adult and parental socio-demographic variables. Approximately one fourth of youth (23%) reported consuming cannabis at least once in the past year. At the same time, 15% had parents who were divorced and 30% parents with a history of depression. The association between parental divorce and cannabis use in young adults was not statistically significant (adjusted OR: 1.50; 95% CI: 0.97-2.31). History of parental depression conferred a marginally statistically significant 42% higher odds of young adult cannabis use (adjusted OR: 1.42; 95% CI: 1.00-2.01). Young adults who experienced both parental history of divorce and depression were more than two times as likely to be current cannabis users compared to those who experienced neither of these (adjusted OR: 2.38; 95% CI: 1.26-4.48). Our findings highlight the critical importance of considering familial context in understanding cannabis use in young adults. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Identity and School History: The Perspective of Young People from the Netherlands and England

ERIC Educational Resources Information Center

Grever, Maria; Haydn, Terry; Ribbens, Kees

2008-01-01

The article presents the findings from a survey of over 400 young people in metropolitan areas in the Netherlands and England concerning their views on identity and school history. The research explored pupils' ideas about which facets of history were of interest to them, what history they believed should be taught in schools, and their views on…

The crowded life is a slow life: Population density and life history strategy.

PubMed

Sng, Oliver; Neuberg, Steven L; Varnum, Michael E W; Kenrick, Douglas T

2017-05-01

The world population has doubled over the last half century. Yet, research on the psychological effects of human population density, once a popular topic, has decreased over the past few decades. Applying a fresh perspective to an old topic, we draw upon life history theory to examine the effects of population density. Across nations and across the U.S. states (Studies 1 and 2), we find that dense populations exhibit behaviors corresponding to a slower life history strategy, including greater future-orientation, greater investment in education, more long-term mating orientation, later marriage age, lower fertility, and greater parental investment. In Studies 3 and 4, experimentally manipulating perceptions of high density led individuals to become more future-oriented. Finally, in Studies 5 and 6, experimentally manipulating perceptions of high density seemed to lead to life-stage-specific slower strategies, with college students preferring to invest in fewer rather than more relationship partners, and an older MTurk sample preferring to invest in fewer rather than more children. This research sheds new insight on the effects of density and its implications for human cultural variation and society at large. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Life History Correlates of Ministerial Success

ERIC Educational Resources Information Center

Umeda, John K.; Frey, David H.

1974-01-01

Life history or biodata correlates of ministerial success were investigated for a group of 92 Seventh-Day Adventist ministers. Two significant bivariate correlations indicated that successful ministers chose their career later than less successful ones and that earning college expenses was predictive of success. (Author/HMV)

Fixation of slightly beneficial mutations: effects of life history.

PubMed

Vindenes, Yngvild; Lee, Aline Magdalena; Engen, Steinar; Saether, Bernt-Erik

2010-04-01

Recent studies of rates of evolution have revealed large systematic differences among organisms with different life histories, both within and among taxa. Here, we consider how life history may affect the rate of evolution via its influence on the fixation probability of slightly beneficial mutations. Our approach is based on diffusion modeling for a finite, stage-structured population with stochastic population dynamics. The results, which are verified by computer simulations, demonstrate that even with complex population structure just two demographic parameters are sufficient to give an accurate approximation of the fixation probability of a slightly beneficial mutation. These are the reproductive value of the stage in which the mutation first occurs and the demographic variance of the population. The demographic variance also determines what influence population size has on the fixation probability. This model represents a substantial generalization of earlier models, covering a large range of life histories.

Life history determines genetic structure and evolutionary potential of host–parasite interactions

PubMed Central

Barrett, Luke G.; Thrall, Peter H.; Burdon, Jeremy J.; Linde, Celeste C.

2009-01-01

Measures of population genetic structure and diversity of disease-causing organisms are commonly used to draw inferences regarding their evolutionary history and potential to generate new variation in traits that determine interactions with their hosts. Parasite species exhibit a range of population structures and life-history strategies, including different transmission modes, life-cycle complexity, off-host survival mechanisms and dispersal ability. These are important determinants of the frequency and predictability of interactions with host species. Yet the complex causal relationships between spatial structure, life history and the evolutionary dynamics of parasite populations are not well understood. We demonstrate that a clear picture of the evolutionary potential of parasitic organisms and their demographic and evolutionary histories can only come from understanding the role of life history and spatial structure in influencing population dynamics and epidemiological patterns. PMID:18947899

Maturation characteristics and life history strategies of the Pacific Lamprey, Entosphenus tridentatus

USGS Publications Warehouse

Clemens, Benjamin J.; van de Wetering, Stan; Sower, Stacia A.; Schreck, Carl B.

2013-01-01

Lampreys (Petromyzontiformes) have persisted over millennia and now suffer a recent decline in abundance. Complex life histories may have factored in their persistence; anthropogenic perturbations in their demise. The complexity of life histories of lampreys is not understood, particularly for the anadromous Pacific lamprey, Entosphenus tridentatus Gairdner, 1836. Our goals were to describe the maturation timing and associated characteristics of adult Pacific lamprey, and to test the null hypothesis that different life histories do not exist. Females exhibited early vitellogenesis – early maturation stages; males exhibited spermatogonia – spermatozoa. Cluster analyses revealed an “immature” group and a “maturing–mature” group for each sex. We found statistically significant differences between these groups in the relationships between (i) body mass and total length in males; (ii) Fulton’s condition factor and liver lipids in males; (iii) the gonadosomatic index (GSI) and liver lipids in females; (iv) GSI and total length in females; (v) mean oocyte diameter and liver lipids; and (vi) mean oocyte diameter and GSI. We found no significant difference between the groups in the relationship of muscle lipids and body mass. Our analyses support rejection of the hypothesis of a single life history. We found evidence for an “ocean-maturing” life history that would likely spawn within several weeks of entering fresh water, in addition to the formerly recognized life history of spending 1 year in fresh water prior to spawning—the “stream-maturing” life history. Late maturity, semelparity, and high fecundity suggest that Pacific lamprey capitalize on infrequent opportunities for reproduction in highly variable environments.

Viviparity and K-selected life history in a Mesozoic marine plesiosaur (Reptilia, Sauropterygia).

PubMed

O'Keefe, F R; Chiappe, L M

2011-08-12

Viviparity is known in several clades of Mesozoic aquatic reptiles, but evidence for it is lacking in the Plesiosauria. Here, we report a Late Cretaceous plesiosaur fossil consisting of a fetus preserved within an adult of the same taxon. We interpret this occurrence as a gravid female and unborn young and hence as definitive evidence for plesiosaur viviparity. Quantitative analysis indicates that plesiosaurs gave birth to large, probably single progeny. The combination of viviparity, large offspring size, and small brood number differs markedly from the pattern seen in other marine reptiles but does resemble the K-selected strategy of all extant marine mammals and a few extant lizards. Plesiosaurs may have shared other life history traits with these clades, such as sociality and maternal care.

On the Psychometric Study of Human Life History Strategies.

PubMed

Richardson, George B; Sanning, Blair K; Lai, Mark H C; Copping, Lee T; Hardesty, Patrick H; Kruger, Daniel J

2017-01-01

This article attends to recent discussions of validity in psychometric research on human life history strategy (LHS), provides a constructive critique of the extant literature, and describes strategies for improving construct validity. To place the psychometric study of human LHS on more solid ground, our review indicates that researchers should (a) use approaches to psychometric modeling that are consistent with their philosophies of measurement, (b) confirm the dimensionality of life history indicators, and (c) establish measurement invariance for at least a subset of indicators. Because we see confirming the dimensionality of life history indicators as the next step toward placing the psychometrics of human LHS on more solid ground, we use nationally representative data and structural equation modeling to test the structure of middle adult life history indicators. We found statistically independent mating competition and Super-K dimensions and the effects of parental harshness and childhood unpredictability on Super-K were consistent with past research. However, childhood socioeconomic status had a moderate positive effect on mating competition and no effect on Super-K, while unpredictability did not predict mating competition. We conclude that human LHS is more complex than previously suggested-there does not seem to be a single dimension of human LHS among Western adults and the effects of environmental components seem to vary between mating competition and Super-K.

Behavioural mediators of genetic life-history trade-offs: a test of the pace-of-life syndrome hypothesis in field crickets.

PubMed

Santostefano, Francesca; Wilson, Alastair J; Niemelä, Petri T; Dingemanse, Niels J

2017-10-11

The pace-of-life syndrome (POLS) hypothesis predicts associations between life history and 'risky' behaviours. Individuals with 'fast' lifestyles should develop faster, reproduce earlier, exhibit more risk-prone behaviours, and die sooner than those with 'slow' lifestyles. While support for POLS has been equivocal to date, studies have relied on individual-level (phenotypic) patterns in which genetic trade-offs may be masked by environmental effects on phenotypes. We estimated genetic correlations between life history (development, lifespan, size) and risky behaviours (exploration, aggression) in a pedigreed population of Mediterranean field crickets ( Gryllus bimaculatus ). Path analyses showed that behaviours mediated some genetic relationships between life history traits, though not those involved in trade-offs. Thus, while specific predictions of POLS theory were not supported, genetic integration of behaviour and life history was present. This implies a major role for risky behaviours in life history evolution. © 2017 The Author(s).

Quality of life in young adults with cerebral palsy.

PubMed

Jiang, Benran; Walstab, Janet; Reid, Susan M; Davis, Elise; Reddihough, Dinah

2016-10-01

Little is known about the quality of life (QOL) of young adults with cerebral palsy. This cross-sectional analysis compares the QOL of a cohort of young Australian adults with CP with a cohort of able-bodied peers to explore the relationship between QOL and impairments, functioning, and social participation. Young adults identified from the Victorian Cerebral Palsy Register were invited to complete a survey about QOL, gross motor function, independence in self-care, and social participation. QOL was assessed with the Quality of Life Instrument for Young Adults (YAQOL). A general population sample of young North American adults, who had completed the YAQOL was selected for comparison. Surveys and consent forms were completed by 335 young adults or their proxies, an overall participation rate of 63% of those located. The mean age of the study participants was 24.7 [s.d = 2.8] years; 51% were male and 49% female. Two hundred and seven (62%) of the 335 participants self-reported their QOL. When compared with the general population sample, self-reporting participants had similar QOL scores for the social relationship and environmental context domains (p > 0.05), while QOL scores were lower for the physical health, psychological well-being, and role function domains (p < 0.001). There was no association between psychological well-being and variables related to body structure and gross motor function in young adults with CP. Contrary to the assumption that young adults with severe CP have low psychosocial well-being, it is apparent that these individuals can have good psychosocial well-being regardless of their disability. Copyright © 2016 Elsevier Inc. All rights reserved.

Organize! A Look at Labor History in Young Adult Books.

ERIC Educational Resources Information Center

Overstreet, Deborah Wilson

2001-01-01

Explores how labor history has been written in books for young readers. Discusses 12 books that focus on the "monstrous working conditions, the miserable poverty of the workers, and the callous apathy of the bosses." Notes that these novels avoid any meaningful discussion of the inherent injustices of capitalism, class structure, and the belief in…

Life-history correlations with seasonal cold hardiness in maritime pine.

PubMed

Prada, Eva; Climent, José; Alía, Ricardo; Díaz, Raquel

2016-12-01

Plants have developed mechanisms to withstand stressful environmental conditions, but the high energetic cost of these mechanisms may involve exchanges with other key functions. While trade-offs between cold hardiness and growth rates are a general assumption, we lack information regarding genetically based trade-offs between cold hardiness and other life-history traits. Such information has strong implications for tree conservation and breeding, especially in the context of ongoing climate change. We used a common garden progeny test to examine the relationships between seasonal cold hardiness and life-history traits of growth, reproduction, juvenile ontogeny, and phenology in 75 families of six maritime pine (Pinus pinaster Ait.) populations, three of continental and three of coastal origins. We found a clear differentiation among populations with regard to cold hardiness and life-history traits. Two continental Iberian populations showed high cold tolerance and slower growth, but faster ontogenetic development in relation to both vegetative heteroblastic change in juveniles and the onset of female reproduction. The coastal populations displayed the opposite behavior, while the continental Moroccan population presented a unique combination of traits. We confirmed trade-offs between cold-hardiness and growth at the population level, but not within populations. There were no trade-offs with other life-history traits at either level. Relevant local adaptation syndromes were identified in the relationship between cold hardiness and life-history traits. These should be considered in developing tree management guidelines aimed at increasing productivity or adaptability under the expected conditions of climate change. © 2016 Botanical Society of America.

Linking habitat structure to life history strategy: Insights from a Mediterranean killifish

NASA Astrophysics Data System (ADS)

Cavraro, Francesco; Daouti, Irini; Leonardos, Ioannis; Torricelli, Patrizia; Malavasi, Stefano

2014-01-01

Modern theories of life history evolution deal with finding links between environmental factors, demographic structure of animal populations and the optimal life history strategy. Small-sized teleost fish, occurring in fragmented populations under contrasting environments, have been widely used as study models to investigate these issues. In the present study, the Mediterranean killifish Aphanius fasciatus was used to investigate the relationships between some habitat features and life history strategy. We selected four sites in the Venice lagoon inhabited by this species, exhibiting different combinations of two factors: overall adult mortality, related to intertidal water coverage and a consequent higher level of predator exposure, and the level of sediment organic matter, as indicator of habitat trophic richness. Results showed that these were the two most important factors influencing demography and life history traits in the four sites. Fish from salt marshes with high predator pressure were smaller and produced a higher number of eggs, whereas bigger fish and a lower reproductive investment were found in the two closed, not tidally influenced habitats. Habitat richness was positively related with population density, but negatively related with growth rate. In particular the synergy between high resources and low predation level was found to be important in shaping peculiar life history traits. Results were discussed in the light of the interactions between selective demographic forces acting differentially on age/size classes, such as predation, and habitat trophic richness that may represent an important energetic constraint on life history traits. The importance to link habitat productivity and morphology to demographic factors for a better understanding of the evolution of life history strategy under contrasting environments was finally suggested.

Differences in sleep quality and health-related quality of life in young adults with allergies and asthma and their healthy peers.

PubMed

Molzon, Elizabeth S; Bonner, Margaret S; Hullmann, Stephanie E; Ramsey, Rachelle R; Suorsa, Kristina I; Chaney, John M; Mullins, Larry L

2013-01-01

The current study examined the relationship between sleep quality and health-related quality of life (HRQOL). Participants were 501 undergraduate students with allergies (167), asthma + allergies (167), or with no history of a chronic illness (167) completed study measures from August 2011 to April 2012. The undergraduate students completed questionnaires online as part of a larger study of psychosocial adjustment of young adults. Young adults with allergies and asthma + allergies reported significantly worse sleep quality and HRQOL than healthy peers. Additionally, those with allergies and asthma + allergies had significantly more sleep disturbances and used sleeping medication significantly more often in the previous month than healthy peers. These results highlight concerns regarding quality of life and sleep problems in an often-overlooked population. Importantly, sleep difficulties can result in difficulties in daily living and impairment in academic functioning.

Rapid weight gain after birth predicts life history and reproductive strategy in Filipino males

PubMed Central

Kuzawa, Christopher W.; McDade, Thomas W.; Adair, Linda S.; Lee, Nanette

2010-01-01

Ecological cues during prenatal and postnatal development may allow organisms to adjust reproductive strategy. The hypothalamic-pituitary-gonadal (HPG) axis is a prime candidate for adaptive plasticity as a result of its critical period of birth to 6 mo (B6M) in humans and the role of testosterone in the development and maintenance of costly sexually dimorphic somatic and behavioral traits. We hypothesized that weight velocity specific to B6M would predict male life history characteristics, including maturational timing, reproductive hormones, adult size, strength, and sexual activity. Data come from 770 Filipino men (age 20.5–22.5 y) followed since birth, with predictor variables including birth weight and weight velocities calculated at 6-mo intervals during the first 2 y of life. As expected, infants who were breastfed experienced less diarrhea, lived in wealthier households with better hygiene, and grew faster from B6M. Males with rapid B6M growth reached puberty earlier and, as young adults, had higher testosterone levels, were taller, more muscular, and had higher grip strength. They also had sex earlier and were more likely to report having had sex in the past month, resulting in more lifetime sex partners. Relationships between B6M weight gain and physical outcomes were generally not present or weaker in female subjects. We conclude that rapid weight gain specific to the brief postnatal hypothalamic-pituitary-gonadal critical period predicts early maturation and sexual activity, elevated hormone production, and more costly adult somatic characteristics among the male subjects in this sample. These findings provide evidence for early life developmental plasticity in male life history and reproductive strategy in humans. PMID:20837542

Social Confidence in Early Adulthood Among Young People With and Without a History of Language Impairment

PubMed Central

Durkin, Kevin; Toseeb, Umar; Botting, Nicola; Pickles, Andrew

2017-01-01

Purpose The purposes of this study were to test the predictions that lower self-esteem and higher shyness in individuals with a history of language impairment (LI) would continue from adolescence into early adulthood and that those with LI would have lower social self-efficacy in early adulthood. Method Participants were young people with a history of LI and a comparison group of age-matched peers. Both groups were tested at ages 17 and 24 years. Participants completed measures of language ability, nonverbal IQ, shyness, global self-esteem, and (at age 24 years only) social self-efficacy. Results Young adults with LI scored lower than age-matched peers on self-esteem, higher on shyness, and lower on social self-efficacy (medium to large effect sizes). In line with expectations, in the group with LI, language ability in adolescence predicted shyness in young adulthood, which, in turn, was negatively associated with self-esteem. There was also a direct association between language ability in adolescence and self-esteem in young adulthood. Conclusions Young people with a history of LI are likely to be entering adulthood less socially confident than their peers. Interventions may be desirable for young adults with LI, and the present findings indicate social self-efficacy as a key area of social confidence that calls for practitioners' attention. PMID:28586830

Dynamics of body time, social time and life history at adolescence.

PubMed

Worthman, Carol M; Trang, Kathy

2018-02-21

Recent opposing trends towards earlier physical maturation and later social maturation present a conundrum of apparent biological-social mismatch. Here we use life history analysis from evolutionary ecology to identify forces that drive these shifts. Together with findings in developmental science, our life history analysis indicates that adolescence is a distinctive period for biological embedding of culture. Ethnographic evidence shows that mass education is a novel feature of the globalizing cultural configurations of adolescence, which are driven by transformations in labour, livelihood and lifestyle. Evaluation of the life history trade-offs and sociocultural ecologies that are experienced by adolescents may offer a practical basis for enhancing their development.

Dynamics of body time, social time and life history at adolescence

NASA Astrophysics Data System (ADS)

Worthman, Carol M.; Trang, Kathy

2018-02-01

Recent opposing trends towards earlier physical maturation and later social maturation present a conundrum of apparent biological-social mismatch. Here we use life history analysis from evolutionary ecology to identify forces that drive these shifts. Together with findings in developmental science, our life history analysis indicates that adolescence is a distinctive period for biological embedding of culture. Ethnographic evidence shows that mass education is a novel feature of the globalizing cultural configurations of adolescence, which are driven by transformations in labour, livelihood and lifestyle. Evaluation of the life history trade-offs and sociocultural ecologies that are experienced by adolescents may offer a practical basis for enhancing their development.

Life Course Status and Exchanges of Support between Young Adults and Parents

ERIC Educational Resources Information Center

Bucx, Freek; van Wel, Frits; Knijn, Trudie

2012-01-01

The authors investigated intergenerational support exchanges in relation to young adults' life course status. In a sample of 2,022 young adults (ages 18-34 years) in The Netherlands, single young adults reported receiving more advice from parents than married young adults, and those with children of their own received more practical support.…

Predicting life-history adaptations to pollutants

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

Maltby, L.

1995-12-31

Animals may adapt to pollutant stress so that individuals from polluted environments are less susceptible than those from unpolluted environments. In addition to such direct adaptations, animals may respond to pollutant stress by life-history modifications; so-called indirect adaptations. This paper will demonstrate how, by combining life-history theory and toxicological data, it is possible to predict stress-induced alterations in reproductive output and offspring size. Pollutant-induced alterations in age-specific survival in favor of adults and reductions in juvenile growth, conditions are predicted to select for reduced investment in reproduction and the allocation of this investment into fewer, larger offspring. Field observations onmore » the freshwater crustaceans, Asellus aquaticus and Gammarus pulex, support these predictions. Females from metal-polluted sites had lower investment in reproduction and produced larger offspring than females of the same species from unpolluted sites. Moreover, interpopulation differences in reproductive biology persisted in laboratory cultures indicating that they had a genetic basis and were therefore due to adaptation rather than acclimation. The general applicability of this approach will be considered.« less

The History and Timing of Depression Onset as Predictors of Young Adult Self-Esteem

ERIC Educational Resources Information Center

Gayman, Mathew D.; Lloyd, Donald A.; Ueno, Koji

2011-01-01

Depression often emerges early in the lifecourse and is consistently shown to be associated with poor self-esteem. The 3 main objectives of the current study are to (1) evaluate the association between a history major depression and self-esteem in young adulthood, (2) assess the relationship between timing of depression onset and young adult…

Seedling architecture and life history evolution in pines

Treesearch

Steven H. Strauss; F. Thomas Ledig

1985-01-01

Much of the work on life history evolution in plants has dealt with allocation of reproductive effort (Abrahamson 1975; Abrahamson and Gadgil 1973; Gaines et al. 1974; McNaughton 1975; Oka 1976; Stearns 1976, 1977, 1980; Newell and Tramer 1978; Primack 1979). The juvenile period, however, occupies a major and critical portion of the life cycle of many species....

Relationship between family quality of life and day occupations of young people with Down syndrome.

PubMed

Foley, Kitty-Rose; Girdler, Sonya; Downs, Jenny; Jacoby, Peter; Bourke, Jenny; Lennox, Nick; Einfeld, Stewart; Llewellyn, Gwynnyth; Parmenter, Trevor R; Leonard, Helen

2014-09-01

To explore relationships between family quality of life, day occupations and activities of daily living (ADL) of young persons with Down syndrome. Data were collected from 150 families with a young person with Down syndrome aged 16-30 years participating in the Down syndrome "Needs Opinions Wishes" database. Data described the young person's characteristics (including functional abilities, behaviour and day occupations) and family characteristics (including income, family and community supports and quality of life). Compared to families of young people attending open employment, families of young people participating in sheltered employment tended to report poorer family quality of life, after adjusting for personal characteristics, behaviour and income (coeff -6.78, 95 % CI -14.38, 0.81). Family supports reduced this relationship (coeff -6.00, 95 % CI -12.76, 0.76). Families of young people with greater functioning in ADL reported better family quality of life regardless of personal and environmental factors (coeff 0.45, 95 % CI 0.05, 0.85) and inclusion of family factors such as family supports reduced this association (coeff 0.29, 95 % CI -0.10, 0.67). Participation of young people with Down syndrome in open employment may positively influence family quality of life. Services that facilitate functioning in ADL and assist the families in accessing suitable family supports have the potential to positively influence family quality of life.

Using Age-Based Life History Data to Investigate the Life Cycle and Vulnerability of Octopus cyanea

PubMed Central

Herwig, Jade N.; Depczynski, Martial; Roberts, John D.; Semmens, Jayson M.; Gagliano, Monica; Heyward, Andrew J.

2012-01-01

Octopus cyanea is taken as an unregulated, recreationally fished species from the intertidal reefs of Ningaloo, Western Australia. Yet despite its exploitation and importance in many artisanal fisheries throughout the world, little is known about its life history, ecology and vulnerability. We used stylet increment analysis to age a wild O. cyanea population for the first time and gonad histology to examine their reproductive characteristics. O. cyanea conforms to many cephalopod life history generalisations having rapid, non-asymptotic growth, a short life-span and high levels of mortality. Males were found to mature at much younger ages and sizes than females with reproductive activity concentrated in the spring and summer months. The female dominated sex-ratios in association with female brooding behaviours also suggest that larger conspicuous females may be more prone to capture and suggests that this intertidal octopus population has the potential to be negatively impacted in an unregulated fishery. Size at age and maturity comparisons between our temperate bordering population and lower latitude Tanzanian and Hawaiian populations indicated stark differences in growth rates that correlate with water temperatures. The variability in life history traits between global populations suggests that management of O. cyanea populations should be tailored to each unique set of life history characteristics and that stylet increment analysis may provide the integrity needed to accurately assess this. PMID:22912898

Evolution of monogamy, paternal investment, and female life history in Peromyscus.

PubMed

Jašarević, Eldin; Bailey, Drew H; Crossland, Janet P; Dawson, Wallace D; Szalai, Gabor; Ellersieck, Mark R; Rosenfeld, Cheryl S; Geary, David C

2013-02-01

The timing of reproductive development and associated trade-offs in quantity versus quality of offspring produced across the life span are well documented in a wide range of species. The relation of these aspects of maternal life history to monogamy and paternal investment in offspring is not well studied in mammals, due in part to the rarity of the latter. By using five large, captive-bred populations of Peromyscus species that range from promiscuous mating with little paternal investment (P. maniculatus bairdii) to social and genetic monogamy with substantial paternal investment (P. californicus insignis), we modeled the interaction between monogamy and female life history. Monogamy and high paternal investment were associated with smaller litter size, delayed maternal reproduction that extended over a longer reproductive life span, and larger, higher quality offspring. The results suggest monogamy and paternal investment can alter the evolution of female life-history trajectories in mammals. PsycINFO Database Record (c) 2013 APA, all rights reserved

A Life History Assessment of Early Childhood Sexual Abuse in Women

ERIC Educational Resources Information Center

Vigil, Jacob M.; Geary, David C.; Byrd-Craven, Jennifer

2005-01-01

Life history theory provided a framework for examining the relations among child sexual abuse (CSA), childhood adversity, and patterns of reproductive development and behavior. A community survey that assessed CSA, life history variables (e.g., age of menarche), and social and family background was administered to 623 women (mean age=26.9 years).…

The role of life histories and trophic interactions in population recovery.

PubMed

Audzijonyte, Asta; Kuparinen, Anna

2016-08-01

Factors affecting population recovery from depletion are at the focus of wildlife management. Particularly, it has been debated how life-history characteristics might affect population recovery ability and productivity. Many exploited fish stocks have shown temporal changes towards earlier maturation and reduced adult body size, potentially owing to evolutionary responses to fishing. Whereas such life-history changes have been widely documented, their potential role on stock's ability to recover from exploitation often remains ignored by traditional fisheries management. We used a marine ecosystem model parameterized for Southeastern Australian ecosystem to explore how changes towards "faster" life histories might affect population per capita growth rate r. We show that for most species changes towards earlier maturation during fishing have a negative effect (3-40% decrease) on r during the recovery phase. Faster juvenile growth and earlier maturation were beneficial early in life, but smaller adult body sizes reduced the lifetime reproductive output and increased adult natural mortality. However, both at intra- and inter-specific level natural mortality and trophic position of the species were as important in determining r as species longevity and age of maturation, suggesting that r cannot be predicted from life-history traits alone. Our study highlights that factors affecting population recovery ability and productivity should be explored in a multi-species context, where both age-specific fecundity and survival schedules are addressed simultaneously. It also suggests that contemporary life-history changes in harvested species are unlikely to increase their resilience and recovery ability. © 2016 Society for Conservation Biology.

Effects of maternal history of depression and early life maltreatment on children's health-related quality of life.

PubMed

Dittrich, Katja; Fuchs, Anna; Bermpohl, Felix; Meyer, Justus; Führer, Daniel; Reichl, Corinna; Reck, Corinna; Kluczniok, Dorothea; Kaess, Michael; Hindi Attar, Catherine; Möhler, Eva; Bierbaum, Anna-Lena; Zietlow, Anna-Lena; Jaite, Charlotte; Winter, Sibylle Maria; Herpertz, Sabine C; Brunner, Romuald; Bödeker, Katja; Resch, Franz

2018-01-01

There is a well-established link between maternal depression and child mental health. Similar effects have been found for maternal history of early life maltreatment (ELM). However, studies investigating the relationship of children's quality of life and maternal depression are scarce and none have been conducted for the association with maternal ELM. The aim of the present study was to investigate the effects of maternal history of ELM and depression on children's health-related quality of life and to identify mediating factors accounting for these effects. Our study involved 194 mothers with and without history of depression and/or ELM and their children between five and 12 years. Children's health-related quality of life was assessed by maternal proxy- and child self-ratings using the KIDSCREEN. We considered maternal sensitivity and maternal parenting stress as potential mediators. We found an effect of maternal history of depression but not of maternal history of ELM on health-related quality of life. Maternal stress and sensitivity mediated the effects of maternal depression on child global health-related quality of life, as well as on the dimensions Autonomy & Parent Relation, School Environment (maternal and child rating), and Physical Wellbeing (child rating). Due to the cross-sectional design of the study, causal interpretations must be made with caution. Some scales yielded low internal consistency. Maternal impairments in areas of parenting which possibly developed during acute depression persist even after remission of acute affective symptoms. Interventions should target parenting stress and sensitivity in parents with prior depression. Copyright © 2017 Elsevier B.V. All rights reserved.

Are Expectations the Missing Link between Life History Strategies and Psychopathology?

PubMed

Kavanagh, Phillip S; Kahl, Bianca L

2018-01-01

Despite advances in knowledge and thinking about using life history theory to explain psychopathology there is still a missing link. That is, we all have a life history strategy, but not all of us develop mental health problems. We propose that the missing link is expectations - a mismatch between expected environmental conditions (including social) set by variations in life history strategies and the current environmental conditions. The mismatch hypothesis has been applied at the biological level in terms of health and disease and we believe that it can also be applied more broadly at the psychological level in terms of perceived expectations in the social environment and the resulting distress-psychopathology-that manifests when our expectations are not met.

Histoires de vie et Formation de Nouveaux Savoirs Vitaux (Life Histories and the Formation of New Life Knowledge).

ERIC Educational Resources Information Center

Pineau, Gaston

1994-01-01

Describes the use of life histories as a means for making sense of personal events and their application to education. Distinguishes three models for the use of life histories in education: the biographical model, the autobiographical model, and the dialectical model. (22 citations) (MAB)

Age-Friendliness and Life Satisfaction of Young-Old and Old-Old in Hong Kong

PubMed Central

Au, Alma M. L.; Yip, H. M.; Kwok, Jackie Y. C.; Lai, K. Y.; Leung, K. M.; Lee, Anita L. F.; Lai, Daniel W. L.; Tsien, Teresa; Lai, Simon M. K.

2017-01-01

Age-friendliness, promoted by the World Health Organization (WHO), aims to enable and support individuals in different aspects of life for fostering life satisfaction and personal well-being as they age. We identified specific aspect(s) of age-friendliness associated with life satisfaction and examined similarities and differences in age-friendliness and life satisfaction in young-old and old-old adults. Six hundred and eighty-two ageing adults were asked to complete a survey questionnaire consisting of the Age-friendly City Scale, Satisfaction with Life Scale, and sociodemographic variables. Multiple linear regression analysis was used to examine the effects of various domains of age-friendliness on life satisfaction among the young-old adults (aged 65 to 74, n = 351) and the old-old adults (aged 75 to 97, n = 331). Common domains associated with life satisfaction in both young-old and old-old groups were transportation and social participation. Community and health services were associated with life satisfaction for the young-old group only. On the other hand, civic participation and employment was significantly associated with the old-old group only. Social participation is important for the young-old and the old-old. Ageing older adults can be a resource to the society. Implications for promoting and implementing age-friendliness were discussed in the context of successful and productive ageing and the need for a more refined taxonomy of social activities. PMID:28348584

Unravelling the life history of Amazonian fishes through otolith microchemistry

PubMed Central

Hermann, Theodore W.; Stewart, Donald J.; Limburg, Karin E.; Castello, Leandro

2016-01-01

Amazonian fishes employ diverse migratory strategies, but the details of these behaviours remain poorly studied despite numerous environmental threats and heavy commercial exploitation of many species. Otolith microchemistry offers a practical, cost-effective means of studying fish life history in such a system. This study employed a multi-method, multi-elemental approach to elucidate the migrations of five Amazonian fishes: two ‘sedentary’ species (Arapaima sp. and Plagioscion squamosissimus), one ‘floodplain migrant’ (Prochilodus nigricans) and two long-distance migratory catfishes (Brachyplatystoma rousseauxii and B. filamentosum). The Sr : Ca and Zn : Ca patterns in Arapaima were consistent with its previously observed sedentary life history, whereas Sr : Ca and Mn : Ca indicated that Plagioscion may migrate among multiple, chemically distinct environments during different life-history stages. Mn : Ca was found to be potentially useful as a marker for identifying Prochilodus's transition from its nursery habitats into black water. Sr : Ca and Ba : Ca suggested that B. rousseauxii resided in the Amazon estuary for the first 1.5–2 years of life, shown by the simultaneous increase/decrease of otolith Sr : Ca/Ba : Ca, respectively. Our results further suggested that B. filamentosum did not enter the estuary during its life history. These results introduce what should be a productive line of research desperately needed to better understand the migrations of these unique and imperilled fishes. PMID:27429777

Quantitative genetics of immunity and life history under different photoperiods.

PubMed

Hammerschmidt, K; Deines, P; Wilson, A J; Rolff, J

2012-05-01

Insects with complex life-cycles should optimize age and size at maturity during larval development. When inhabiting seasonal environments, organisms have limited reproductive periods and face fundamental decisions: individuals that reach maturity late in season have to either reproduce at a small size or increase their growth rates. Increasing growth rates is costly in insects because of higher juvenile mortality, decreased adult survival or increased susceptibility to parasitism by bacteria and viruses via compromised immune function. Environmental changes such as seasonality can also alter the quantitative genetic architecture. Here, we explore the quantitative genetics of life history and immunity traits under two experimentally induced seasonal environments in the cricket Gryllus bimaculatus. Seasonality affected the life history but not the immune phenotypes. Individuals under decreasing day length developed slower and grew to a bigger size. We found ample additive genetic variance and heritability for components of immunity (haemocyte densities, proPhenoloxidase activity, resistance against Serratia marcescens), and for the life history traits, age and size at maturity. Despite genetic covariance among traits, the structure of G was inconsistent with genetically based trade-off between life history and immune traits (for example, a strong positive genetic correlation between growth rate and haemocyte density was estimated). However, conditional evolvabilities support the idea that genetic covariance structure limits the capacity of individual traits to evolve independently. We found no evidence for G × E interactions arising from the experimentally induced seasonality.

Life history migrations of adult Yellowstone Cutthroat Trout in the upper Yellowstone River

USGS Publications Warehouse

Ertel, Brian D.; McMahon, Thomas E.; Koel, Todd M.; Gresswell, Robert E.; Burckhardt, Jason

2017-01-01

Knowledge of salmonid life history types at the watershed scale is increasingly recognized as a cornerstone for effective management. In this study, we used radiotelemetry to characterize the life history movements of Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri in the upper Yellowstone River, an extensive tributary that composes nearly half of the drainage area of Yellowstone Lake. In Yellowstone Lake, Yellowstone Cutthroat Trout have precipitously declined over the past 2 decades primarily due to predation from introduced Lake Trout Salvelinus namaycush. Radio tags were implanted in 152 Yellowstone Cutthroat Trout, and their movements monitored over 3 years. Ninety-six percent of tagged trout exhibited a lacustrine–adfluvial life history, migrating upstream a mean distance of 42.6 km to spawn, spending an average of 24 d in the Yellowstone River before returning to Yellowstone Lake. Once in the lake, complex postspawning movements were observed. Only 4% of radio-tagged trout exhibited a fluvial or fluvial–adfluvial life history. Low prevalence of fluvial and fluvial–adfluvial life histories was unexpected given the large size of the upper river drainage. Study results improve understanding of life history diversity in potamodromous salmonids inhabiting relatively undisturbed watersheds and provide a baseline for monitoring Yellowstone Cutthroat Trout response to management actions in Yellowstone Lake.

Life Transitions and Mental Health in a National Cohort of Young Australian Women

ERIC Educational Resources Information Center

Lee, Christiana; Gramotnev, Helen

2007-01-01

Young adulthood, a time of major life transitions and risk of poor mental health, may affect emotional well-being throughout adult life. This article uses longitudinal survey data to examine young Australian women's transitions across 4 domains: residential independence, relationships, work and study, and motherhood. Changes over 3 years in…

Understanding a Pakistani Science Teacher's Practice through a Life History Study

ERIC Educational Resources Information Center

Halai, Nelofer

2011-01-01

The purpose of the single case life history study was to understand a female science teacher's conceptions of the nature of science as explicit in her practice. While this paper highlights these understandings, an additional purpose is to give a detailed account of the process of creating a life history account through more than 13 in-depth…

Fast–slow continuum and reproductive strategies structure plant life-history variation worldwide

PubMed Central

Salguero-Gómez, Roberto; Jones, Owen R.; Jongejans, Eelke; Blomberg, Simon P.; Hodgson, David J.; Mbeau-Ache, Cyril; Zuidema, Pieter A.; de Kroon, Hans; Buckley, Yvonne M.

2016-01-01

The identification of patterns in life-history strategies across the tree of life is essential to our prediction of population persistence, extinction, and diversification. Plants exhibit a wide range of patterns of longevity, growth, and reproduction, but the general determinants of this enormous variation in life history are poorly understood. We use demographic data from 418 plant species in the wild, from annual herbs to supercentennial trees, to examine how growth form, habitat, and phylogenetic relationships structure plant life histories and to develop a framework to predict population performance. We show that 55% of the variation in plant life-history strategies is adequately characterized using two independent axes: the fast–slow continuum, including fast-growing, short-lived plant species at one end and slow-growing, long-lived species at the other, and a reproductive strategy axis, with highly reproductive, iteroparous species at one extreme and poorly reproductive, semelparous plants with frequent shrinkage at the other. Our findings remain consistent across major habitats and are minimally affected by plant growth form and phylogenetic ancestry, suggesting that the relative independence of the fast–slow and reproduction strategy axes is general in the plant kingdom. Our findings have similarities with how life-history strategies are structured in mammals, birds, and reptiles. The position of plant species populations in the 2D space produced by both axes predicts their rate of recovery from disturbances and population growth rate. This life-history framework may complement trait-based frameworks on leaf and wood economics; together these frameworks may allow prediction of responses of plants to anthropogenic disturbances and changing environments. PMID:26699477

Fast-slow continuum and reproductive strategies structure plant life-history variation worldwide.

PubMed

Salguero-Gómez, Roberto; Jones, Owen R; Jongejans, Eelke; Blomberg, Simon P; Hodgson, David J; Mbeau-Ache, Cyril; Zuidema, Pieter A; de Kroon, Hans; Buckley, Yvonne M

2016-01-05

The identification of patterns in life-history strategies across the tree of life is essential to our prediction of population persistence, extinction, and diversification. Plants exhibit a wide range of patterns of longevity, growth, and reproduction, but the general determinants of this enormous variation in life history are poorly understood. We use demographic data from 418 plant species in the wild, from annual herbs to supercentennial trees, to examine how growth form, habitat, and phylogenetic relationships structure plant life histories and to develop a framework to predict population performance. We show that 55% of the variation in plant life-history strategies is adequately characterized using two independent axes: the fast-slow continuum, including fast-growing, short-lived plant species at one end and slow-growing, long-lived species at the other, and a reproductive strategy axis, with highly reproductive, iteroparous species at one extreme and poorly reproductive, semelparous plants with frequent shrinkage at the other. Our findings remain consistent across major habitats and are minimally affected by plant growth form and phylogenetic ancestry, suggesting that the relative independence of the fast-slow and reproduction strategy axes is general in the plant kingdom. Our findings have similarities with how life-history strategies are structured in mammals, birds, and reptiles. The position of plant species populations in the 2D space produced by both axes predicts their rate of recovery from disturbances and population growth rate. This life-history framework may complement trait-based frameworks on leaf and wood economics; together these frameworks may allow prediction of responses of plants to anthropogenic disturbances and changing environments.

Personality trait changes among young Finns: the role of life events and transitions.

PubMed

Leikas, Sointu; Salmela-Aro, Katariina

2015-02-01

Recent research has shown that personality traits continue to develop throughout the life span, but most profound changes are typically found during young adulthood. Increasing evidence suggests that life events play a significant role in many of these changes. The present longitudinal study examined the role of work, education, social, and health-related life events in the development of the Big Five traits among young Finns. Participants were originally recruited in 2004 through elementary schools in a middle-sized Finnish city. Participants' Big Five traits and life events were measured via self-reports at ages 20 and 23 (Ns = 597 and 588, respectively). Entering work life, beginning a relationship, and studying in university predicted increases in Conscientiousness, trying drugs predicted increases in Neuroticism, and onset of a chronic disease predicted increases in Neuroticism and Conscientiousness between ages 20 and 23. The results suggest that mature life transitions relate to stronger increases in Conscientiousness in young adulthood, and that non-normative life choices and events may predict increases in Neuroticism. © 2014 Wiley Periodicals, Inc.

Life History Theory and Social Deviance: The Mediating Role of Executive Function

ERIC Educational Resources Information Center

Wenner, C. J.; Bianchi, J.; Figueredo, A. J.; Rushton, J. Philippe; Jacobs, W. J.

2013-01-01

The present work examined predicted relations among Life History strategies, Executive Functions, socially antagonistic attitudes, socially antagonistic behaviors, and general intelligence. Life History (LH) theory predicts that Executive Functions and socially antagonistic attitudes and behaviors underpin an interrelated and coherent set of…

Life stories of young women who experience rejection from their mothers.

PubMed

Mosman, Selina C; Poggenpoel, Marie; Myburgh, Chris

2015-08-12

When a daughter perceives rejection from her mother, she is bound to be sensitive to rejection for most if not all of her life. Such an experience influences almost all future relationships. The purpose of this research was to explore and describe the life stories of young women who perceived rejection from their mothers and to formulate guidelines to assist them. A phenomenological interpretive method that is explorative, descriptive, and contextual was used to explore everyday life experiences. Network sampling was used. In-depth phenomenological interviews were conducted with the young women so that they could define the most important dimensions of their life stories and elaborate on what is relevant to them. They were asked: 'Tell me your life story.' One of the authors also had a life story of perceived maternal rejection; hence an auto-ethnography was critical and was included in the study. Thematic data analysis was applied. Themes that emerged from the data were that the young women: (1) perceive ongoing challenges in forming and sustaining relationships in their lives; (2) experience their lives as conflicted because their relationship with the central core of their existence, their mother, is perceived as tumultuous; and (3) experience fundamental links to be missing in their 'mother-daughter relationship'. Only a few women were interviewed regarding perceived rejection from their mothers. Further research in this regard is imperative.

Telling Modernization: Three Voices. Life History, Gender and the Discourse of Modernization. Roskilde University Life History Project Paper.

ERIC Educational Resources Information Center

Anderson, Linda

The relationship between life history, gender, and the discourse of modernization was examined from the perspective of a researcher with extensive experience performing evaluations about modernization within human services in Denmark. Three stories about site-based management in two human service institutionsa youth center and a boarding school…

Seedling architechture and life history evolution in pines

Treesearch

Steven H. Strauss; F. Thomas Ledig

1985-01-01

Much of the work on life history evolution in plants has dealt with allocation of reproductive effort (Abrahamson 1975; Abrahamson and Gadgil 1973; Gaines et al. 1974; McNaughton 1975; Oka 1976; Stearns 1976, 1977, 1980; Newel1 and Tramer 1978; Primack 1979). The juvenile period, however, occupies a major and critical portion of the life cycle of many species....

Family history and outcome of young patients with breast cancer in the UK (POSH study).

PubMed

Eccles, B K; Copson, E R; Cutress, R I; Maishman, T; Altman, D G; Simmonds, P; Gerty, S M; Durcan, L; Stanton, L; Eccles, D M

2015-07-01

Young patients presenting to surgical clinics with breast cancer are usually aware of their family history and frequently believe that a positive family history may adversely affect their prognosis. Tumour pathology and outcomes were compared in young British patients with breast cancer with and without a family history of breast cancer. Prospective Outcomes in Sporadic versus Hereditary breast cancer (POSH) is a large prospective cohort study of women aged less than 41 years with breast cancer diagnosed and treated in the UK using modern oncological management. Personal characteristics, tumour pathology, treatment and family history of breast/ovarian cancer were recorded. Follow-up data were collected annually. Family history data were available for 2850 patients. No family history was reported by 65·9 per cent, and 34·1 per cent reported breast/ovarian cancer in at least one first- or second-degree relative. Patients with a family history were more likely to have grade 3 tumours (63·3 versus 58·9 per cent) and less likely to have human epidermal growth factor receptor 2-positive tumours (24·7 versus 28·8 per cent) than those with no family history. In multivariable analyses, there were no significant differences in distant disease-free intervals for patients with versus those without a family history, either for the whole cohort (hazard ratio (HR) 0·89, 95 per cent c.i. 0·76 to 1·03; P = 0·120) or when stratified by oestrogen receptor (ER) status (ER-negative: HR 0·80, 0·62 to 1·04, P = 0·101; ER-positive: HR 0·95, 0·78 to 1·15, P = 0·589). Young British patients presenting to breast surgical clinics with a positive family history can be reassured that this is not a significant independent risk factor for breast cancer outcome. © 2015 BJS Society Ltd Published by John Wiley & Sons Ltd.

Early-Life Characteristics, Psychiatric History, and Cognition Trajectories in Later Life

ERIC Educational Resources Information Center

Brown, Maria Teresa

2010-01-01

Purpose of the Study: Although considerable attention has been paid to the relationship between later-life depression and cognitive function, the relationship between a history of psychiatric problems and cognitive function is not very well documented. Few studies of relationships between childhood health, childhood disadvantage, and cognitive…

The association between parental life history and offspring phenotype in Atlantic salmon.

PubMed

Van Leeuwen, Travis E; McLennan, Darryl; McKelvey, Simon; Stewart, David C; Adams, Colin E; Metcalfe, Neil B

2016-02-01

In many taxa there is considerable intraspecific variation in life history strategies from within a single population, reflecting alternative routes through which organisms can achieve successful reproduction. Atlantic salmon Salmo salar (Linnaeus) show some of the greatest within-population variability in life history strategies amongst vertebrates, with multiple discrete male and female life histories co-existing and interbreeding on many spawning grounds, although the effect of the various combinations of life histories on offspring traits remains unknown. Using crosses of wild fish we show here that the life history strategy of both parents was significantly associated with a range of offspring traits. Mothers that had spent longer at sea (2 versus 1 year) produced offspring that were heavier, longer and in better condition at the time of first feeding. However, these relationships disappeared shortly after fry had begun feeding exogenously. At this stage, the juvenile rearing environment (i.e. time spent in fresh water as juveniles) of the mother was a better predictor of offspring traits, with mothers that were faster to develop in fresh water (migrating to sea after two rather than three years of age) producing offspring that had higher maximal metabolic rates, aerobic scopes, and that grew faster. Faster developing fathers (1 year old sneaker males) tended to produce offspring that had higher maximal metabolic rates, were in better body condition and grew faster. The results suggest that both genetic effects and those related to parental early and late life history contribute to offspring traits. © 2016. Published by The Company of Biologists Ltd.

Life adversities and suicidal behavior in young individuals: a systematic review.

PubMed

Serafini, Gianluca; Muzio, Caterina; Piccinini, Giulia; Flouri, Eirini; Ferrigno, Gabriella; Pompili, Maurizio; Girardi, Paolo; Amore, Mario

2015-12-01

Suicidal behavior in young people is a significant public health problem. However, it is not yet clear whether adversities (adverse life events) may be related to suicidality in adolescence and early adulthood. This paper aimed to investigate systematically the association between the type/number of adverse life events and experiences and suicidal behavior in young people. We developed a detailed strategy to search relevant articles in Pubmed, Scopus, PsycInfo, and Science Direct (January 1980-January 2015) about adverse life events and suicidal behavior. Adverse life events and experiences included maltreatment and violence, loss events, intra-familial problems, school and interpersonal problems. Studies were restricted to suicidal behavior in young people aged 10-25 years. The search yielded 245 articles, of which 28 met our inclusion criteria. Most studies reported a strong association between adversities and suicidality (both suicidal ideation and attempts). Based on the main results, the number of adversities or negative life events experienced seemed to have a positive dose-response relationship with youth suicidal behavior. However, the type of event experienced also appeared to matter: one of the most consistent findings was the association between suicidal behavior and experience of sexual abuse. More prospective studies are needed to elucidate the relative importance of risk accumulation and risk specificity for youth suicide.

Youth and young adult suicide: a study of life trajectory.

PubMed

Séguin, Monique; Renaud, Johanne; Lesage, Alain; Robert, Marie; Turecki, Gustavo

2011-07-01

Explore the unique developmental challenges and early adversity faced by youth and young adult who died of suicide. Sixty-seven suicide victims (SG) were compared with 56 living control with no suicidal ideations in the last year, matched for age, gender, and geographical region. Mixed methods were used: consensus DSM-IV diagnoses were formulated based on Structured Clinical Interview for DSM-IV (SCID)-I and -II interviews complemented by medical charts. Life calendar method was conducted with closest third party informant. Life-history calendar served to measure life events and adversity throughout the life course and were analyzed by attributing burden of adversity score per five-year segment, which was then cluster-analyzed to define suicide victim profiles. During the last year, mood disorders, abuse and dependence disorders, and anxiety disorder were between 8 and 63 times more likely to be present in the suicide group. Between 0 and 4 years old, 50% of children in the SG were exposed to abuse, physical and/or sexual violence; 60% between 5 and 9 years old; and by the time they were 10-14 years old, 77% were exposed to these forms of violence. In the control group, the respective figures were 14%, 18% and 34%. In the suicide group, the trajectories leading to suicide are different as we observe two different subgroups, one with early-onset and one with later-onset of adversity. To a large extent, people in the suicide group were exposed to major adversity and they were more likely to present cumulative comorbid disorders. Copyright © 2011 Elsevier Ltd. All rights reserved.

Melanin-specific life-history strategies.

PubMed

Emaresi, Guillaume; Bize, Pierre; Altwegg, Res; Henry, Isabelle; van den Brink, Valentijn; Gasparini, Julien; Roulin, Alexandre

2014-02-01

The maintenance of genetic variation is a long-standing issue because the adaptive value of life-history strategies associated with each genetic variant is usually unknown. However, evidence for the coexistence of alternative evolutionary fixed strategies at the population level remains scarce. Because in the tawny owl (Strix aluco) heritable melanin-based coloration shows different physiological and behavioral norms of reaction, we investigated whether coloration is associated with investment in maintenance and reproduction. Light melanic owls had lower adult survival compared to dark melanic conspecifics, and color variation was related to the trade-off between offspring number and quality. When we experimentally enlarged brood size, light melanic males produced more fledglings but in poorer condition, and they were less often recruited in the local breeding population than those of darker melanic conspecifics. Our results also suggest that dark melanic males allocate a constant effort to raise their brood independently of environmental conditions, whereas lighter melanic males finely adjust reproductive effort in relation to changes in environmental conditions. Color traits can therefore be associated with life-history strategies, and stochastic environmental perturbation can temporarily favor one phenotype over others. The existence of fixed strategies implies that some phenotypes can sometimes display a "maladapted" strategy. Long-term population monitoring is therefore vital for a full understanding of how different genotypes deal with trade-offs.

Person to Person: A Collection of Life History Stories.

ERIC Educational Resources Information Center

Fraenkel, Brenda; Hadfield, Sara

1988-01-01

An oral history project paired deaf high school students with deaf senior citizens for five meetings over a two-month period. The students then wrote up life history stories. The experience gave students experience in interviewing skills, notetaking, and writing as well as developing friendships and increased understanding of deaf older people.…

Young children's family history of stuttering and their articulation, language and attentional abilities: An exploratory study.

PubMed

Choi, Dahye; Conture, Edward G; Tumanova, Victoria; Clark, Chagit E; Walden, Tedra A; Jones, Robin M

The purpose of this study was to determine whether young children who do (CWS) and do not stutter (CWNS) with a positive versus negative family history of stuttering differ in articulation, language and attentional abilities and family histories of articulation, language and attention related disorders. Participants were 25 young CWS and 50 young CWNS. All 75 participants' caregivers consistently reported a positive or negative family history of stuttering across three consecutive time points that were about 8 months apart for a total of approximately 16 months. Each participant's family history focused on the same, relatively limited number of generations (i.e., participants' parents & siblings). Children's family history of stuttering as well as articulation, language, and attention related disorders was obtained from one or two caregivers during an extensive interview. Children's speech and language abilities were measured using four standardized articulation and language tests and their attentional abilities were measured using caregiver reports of temperament. Findings indicated that (1) most caregivers (81.5% or 75 out 92) were consistent in their reporting of positive or negative history of stuttering; (2) CWNS with a positive family history of stuttering, compared to those with a negative family history of stuttering, were more likely to have reported a positive family history of attention deficit/hyperactivity disorder (ADHD), and (3) CWNS with a positive family history of stuttering had lower language scores than those with a negative family history of stuttering. However, there were no such significant differences in family histories of ADHD and language scores for CWS with a positive versus negative family history of stuttering. In addition, although 24% of CWS versus 12% of CWNS's caregivers reported a positive family history of stuttering, inferential analyses indicated no significant differences between CWS and CWNS in relative proportions of family

Psychological needs, purpose in life, and problem video game playing among Chinese young adults.

PubMed

Wu, Anise M S; Lei, Lamis L M; Ku, Lisbeth

2013-01-01

The negative impacts of excessive and problematic video game playing on both children and adults are attracting increasing concern. Based on self-determination theory (SDT; Ryan & Deci, 2000), this study hypothesized that the three basic psychological needs of autonomy, competence, and relatedness are positively associated with purpose in life, which in turn acts as a protective factor against problem video game playing among Chinese young adult players. Through a questionnaire survey with a sample of 165 Chinese adults aged between 18 and 30 years (mean age = 22.7 years), we found that perceived autonomy, competence, relatedness, and purpose in life were all negatively correlated with problem game playing. The demographic and psychological factors explained 38% of the variances of problem game playing. Specifically, gender, perceived relatedness, and purpose in life emerged as the three most salient predictors of problem game playing among the Chinese young adults. The mediating role of purpose in life was evidenced and it was found that purpose in life mediated the influences of the psychological needs proposed by SDT on problem game playing. Moreover, young men were significantly more susceptible to problem game playing than their female counterparts. To conclude, psychological needs and purpose in life influenced Chinese young adults' vulnerability to problem game playing directly or indirectly. Intervention programs that encourage social involvement and voluntary work, as well as counseling service that helps clients to search for life purpose, are suggested for intervening in problem game playing among Chinese young adults.

From Environment to Mating Competition and Super-K in a Predominantly Urban Sample of Young Adults.

PubMed

Richardson, George B; Dariotis, Jacinda K; Lai, Mark H C

2017-01-01

Recent research suggests human life history strategy (LHS) may be subsumed by multiple dimensions, including mating competition and Super-K, rather than one. In this study, we test whether a two-dimensional structure best fit data from a predominantly urban sample of young adults ages 18-24. We also test whether latent life history dimensions are associated with environmental harshness and unpredictability as predicted by life history theory. Results provide evidence that a two-dimensional model best fit the data. Furthermore, a moderate inverse residual correlation between mating competition and Super-K was found, consistent with a life history trade-off. Our findings suggest that parental socioeconomic status may enhance investment in mating competition, that harshness might persist into young adulthood as an important correlate of LHS, and that unpredictability may not have significant effects in young adulthood. These findings further support the contention that human LHS is multidimensional and environmental effects on LHS are more complex than previously suggested. The model presented provides a parsimonious explanation of an array of human behaviors and traits and can be used to inform public health initiatives, particularly with respect to the potential impact of environmental interventions.

Dynamics and life histories of northern ungulates in changing environments

NASA Astrophysics Data System (ADS)

Hendrichsen, D. K.

2011-12-01

Regional climate and local weather conditions can profoundly influence life history parameters (growth, survival, fecundity) and population dynamics in northern ungulates (Post and Stenseth 1999, Coulson et al. 2001). The influence is both direct, for example through reduced growth or survival (Aanes et al. 2000, Tyler et al. 2008), and indirect, for example through changes in resource distribution, phenology and quality, changes which subsequently influence consumer dynamics (Post et al. 2008). By comparing and contrasting data from three spatially independent populations of ungulates, I discuss how variation in local weather parameters and vegetation growth influence spatial and temporal dynamics through changes in life history parameters and/or behavioural dynamics. The data originate from long term (11-15 years) monitoring data from three populations of ungulates in one subarctic and two high Arctic sites; semi-domesticated reindeer (Rangifer tarandus tarandus) in northern Norway, Svalbard reindeer (R. t. platyrhynchus) on Spitsbergen and muskoxen (Ovibos moschatus) in Northeast Greenland. The results show that juvenile animals can be particularly vulnerable to changes in their environment, and that this is mirrored to different degrees in the spatio-temporal dynamics of the three populations. Adverse weather conditions, acting either directly or mediated through access to and quality of vegetation, experienced by young early in life, or even by their dams during pregnancy, can lead to reduced growth, lower survival and reduced reproductive performance later in life. The influence of current climatic variation, and the predictions of how local weather conditions may change over time, differs between the three sites, resulting in potentially different responses in the three populations. Aanes R, Saether BE and Øritsland NA. 2000. Fluctuations of an introduced population of Svalbard reindeer: the effects of density dependence and climatic variation. Ecography

Girls Like Us: Looking at History through the American Girl Series

ERIC Educational Resources Information Center

Philpott, Sarah Lewis

2014-01-01

Quality historical fiction enables readers to imagine what life might have been like for a variety of people, particularly those not typically written about in history texts. Social history of an era is often of particular interest to young students. This article looks at using the American Girl Series to interest students in history and provides…

Do pioneers have r-selected traits? Life history patterns among colonizing terrestrial gastropods.

PubMed

Bengtsson, J; Baur, B

1993-05-01

We examine whether pioneer species of terrestrial gastropods (snails and slugs) possess particular life history traits commonly associated with r-selection, using data on gastropod colonization in four areas in north-west Europe (the Kvarken and Tvärminne archipelagos in the Baltic, polder woods in IJsselmeer, and a rehabilitated quarry near Maastricht). Data on age at first reproduction, longevity, clutch size, egg size and lifetime fecundity were gathered from the literature. In order to control for potentially confounding effects of body size on life history traits, we compared the residuals from the allometric relations between life history traits and body size for pioneers and non-pioneers. In snails, all life history traits examined were related to body size. In slugs, all traits except age at first reproduction scaled with body size. Body sizes did not differ between pioneers and non-pioneers in any area. In all four areas, there were no significant differences between pioneers and non-pioneers in any of the life history traits examined, after body size had been taken into account. This indicates that pioneer terrestrial gastropods generally cannot be regarded as r-selected. Pioneer species may possess any of several life history strategies, and the combinations of traits shown by them may have little in common with the r-K selection concept.

Reevaluating geographic variation in life-history traits of a widespread Nearctic amphibian

USGS Publications Warehouse

Davenport, Jon M.; Hossack, Blake R.

2016-01-01

Animals from cold environments are usually larger than animals from warm environments, which often produce clines in body size. Because variation in body size can lead to trade-offs between growth and reproduction, life-history traits should also vary across climatic gradients. To determine if life-history traits of wood frogs Rana sylvatica vary with climate, we examined female and male body length, clutch size, and ovum size from 37 locations across an unprecedented 32° of latitude. In conflict with recent research, body size, and ovum size decreased in cold climates and at higher latitudes. Clutch size did not vary with climate or latitude, but reproductive effort (clutch size:female size) did, suggesting selection for a life-history traits that favors maximizing propagule number over propagule size in cold climates. With accelerating climate change that will expose populations to novel environmental conditions, it is important to identify the limits of adaptation, which can be informed by greater understanding of variation in life-history traits.

Transcriptomic and macroevolutionary evidence for phenotypic uncoupling between frog life history phases

PubMed Central

Wollenberg Valero, Katharina C.; Garcia-Porta, Joan; Rodríguez, Ariel; Arias, Mónica; Shah, Abhijeet; Randrianiaina, Roger Daniel; Brown, Jason L.; Glaw, Frank; Amat, Felix; Künzel, Sven; Metzler, Dirk; Isokpehi, Raphael D.; Vences, Miguel

2017-01-01

Anuran amphibians undergo major morphological transitions during development, but the contribution of their markedly different life-history phases to macroevolution has rarely been analysed. Here we generate testable predictions for coupling versus uncoupling of phenotypic evolution of tadpole and adult life-history phases, and for the underlying expression of genes related to morphological feature formation. We test these predictions by combining evidence from gene expression in two distantly related frogs, Xenopus laevis and Mantidactylus betsileanus, with patterns of morphological evolution in the entire radiation of Madagascan mantellid frogs. Genes linked to morphological structure formation are expressed in a highly phase-specific pattern, suggesting uncoupling of phenotypic evolution across life-history phases. This gene expression pattern agrees with uncoupled rates of trait evolution among life-history phases in the mantellids, which we show to have undergone an adaptive radiation. Our results validate a prevalence of uncoupling in the evolution of tadpole and adult phenotypes of frogs. PMID:28504275

Libraries of life: using life history books with depressed care home residents.

PubMed

Plastow, Nicola Ann

2006-01-01

Depression is a common, and often undetected, psychiatric disorder in geriatric care home residents. Reminiscence, an independent nursing therapy used by a variety of health and social care professionals, can prevent or reduce depression. This practice development project explored the use of reminiscence life history books as an interpersonal therapeutic tool with 3 depressed care-home residents living in residential care and skilled nursing facilities. The process of choosing to produce a book, assessment of capabilities, and methods of construction are described using 3 illustrative case studies. Three themes emerged: reviewing the past, accepting the present, and dreaming of an alternative future. This project demonstrated that life history books, tailored to individual needs and abilities, can facilitate reminiscence and reduce depression by increasing social interaction. The benefits to residents, their families, and care staff are discussed and the relevance to nursing practice highlighted.

Connecting proximate mechanisms and evolutionary patterns: pituitary gland size and mammalian life history.

PubMed

Kamilar, J M; Tecot, S R

2015-11-01

At the proximate level, hormones are known to play a critical role in influencing the life history of mammals, including humans. The pituitary gland is directly responsible for producing several hormones, including those related to growth and reproduction. Although we have a basic understanding of how hormones affect life history characteristics, we still have little knowledge of this relationship in an evolutionary context. We used data from 129 mammal species representing 14 orders to investigate the relationship between pituitary gland size and life history variation. Because pituitary gland size should be related to hormone production and action, we predicted that species with relatively large pituitaries should be associated with fast life histories, especially increased foetal and post-natal growth rates. Phylogenetic analyses revealed that total pituitary size and the size of the anterior lobe of the pituitary significantly predicted a life history axis that was correlated with several traits including body mass, and foetal and post-natal growth rates. Additional models directly examining the association between relative pituitary size and growth rates produced concordant results. We also found that relative pituitary size variation across mammals was best explained by an Ornstein-Uhlenbeck model of evolution, suggesting an important role of stabilizing selection. Our results support the idea that the size of the pituitary is linked to life history variation through evolutionary time. This pattern is likely due to mediating hormone levels but additional work is needed. We suggest that future investigations incorporating endocrine gland size may be critical for understanding life history evolution. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

Stressful life events, sexual orientation, and cardiometabolic risk among young adults in the United States.

PubMed

Hatzenbuehler, Mark L; Slopen, Natalie; McLaughlin, Katie A; McLaughlin, Kate A

2014-10-01

The goal of the present study was to examine whether sexual minority young adults are more vulnerable to developing cardiometabolic risk following exposure to stressful life events than heterosexual young adults. Data came from the National Longitudinal Study for Adolescent Health (Shin, Edwards, & Heeren, 2009; Brummett et al., 2013), a prospective nationally representative study of U.S. adolescents followed into young adulthood. A total of 306 lesbian, gay, and bisexual (LGB) respondents and 6,667 heterosexual respondents met inclusion criteria for this analysis. Measures of cumulative stressful life events were drawn from all 4 waves of data collection; sexual orientation and cardiometabolic biomarkers were assessed at Wave 4 (2008-2009). Gay/bisexual men exposed to 1-2 (β = 0.71, p = .01) and 5+ (β = 0.87, p = .01) stressful life events had a statistically significant elevation in cardiometabolic risk, controlling for demographics, health behaviors, and socioeconomic status. Moreover, in models adjusted for all covariates, lesbian/bisexual (β = 0.52, p = .046) women with 5+ stressful life events had a statistically significant elevation in cardiometabolic risk. There was no relationship between stressful life events and cardiometabolic risk among heterosexual men or women. Stressful life events during childhood, adolescence, and young adulthood place LGB young adults at heightened risk for elevated cardiometabolic risk as early as young adulthood. The mechanisms underlying this relationship require future study.

Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (Mid-Atlantic)

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

Rogers, S.G.; Van Den Avyle, M.J.

1989-08-01

Species profiles are literature summaries of the life history, distribution and environmental requirements of coastal fishes and invertebrates. Profiles are prepared to assist with environmental impact assessment. The Atlantic menhaden (Brevoortia tyrannus) is an important commercial fish along the Atlantic coast. In the South Atlantic Region, Atlantic menhaden spawn during winter in continental shelf waters. Adults then move inshore and northward in spring; some move into estuaries as far as the brackish-freshwater boundary. Atlantic menhaden larvae in the South Atlantic Region enter estuaries after 1 to 3 months at sea. Young fish move into the shallow regions of estuaries andmore » seem to prefer vegetated marsh habitats. Atlantic menhaden are size-selective plankton feeders as larvae, and filter feeders as juveniles and adults. Due to their large population size, individual growth rates, and seasonal movements, Atlantic menhaden annually consume and redistribute large amounts of energy and materials. They are also important prey for large game fishes such as bluefish (Pomatomus saltatrix), striped bass (Morone saxatilis), and bluefin tuna (Thunnus thynnus). The Atlantic menhaden is associated with estuarine and nearshore systems during all phases of its life cycle. Young menhaden require these food-rich habitats to survive and grown. Destruction of estuarine wetlands has decreased nursery habitat available to Atlantic menhaden and other estuarine wetlands has decreased nursery habitat available to Atlantic menhaden and other estuarine-dependent species. 115 refs., 2 figs., 2 tabs.« less

Understanding the relationship transitions and associated end of life clinical needs of young adults with life-limiting illnesses: A triangulated longitudinal qualitative study

PubMed Central

Johnston, Bridget; Jindal-Snape, Divya; Pringle, Jan; Gold, Libby; Grant, Jayne; Dempsey, Raymond; Scott, Ros; Carragher, Pat

2016-01-01

Background: Care of young adults with life-limiting illnesses can often be complex due to the fact that they are growing and developing within the continuing presence of their illness. There is little research conducted nationally and internationally, which has examined the life issues of young adults or taken a longitudinal approach to understand such issues over a period of time. Aim: To gain clear understanding of one particular and pertinent life issue—relationship transition—occurring in the context of being a young adult with a life-limiting illness and the clinical needs arising from this. Design: This was a triangulated, longitudinal, qualitative study involving young adults with life-limiting illnesses and their significant others, namely, family members and healthcare professionals. Semi-structured interviews were conducted with participants and analysed using thematic analysis. Clinical case note reviews were also carried out. Setting/participants: A total of 12 young adults (aged between 17 and 23 years) from 2 hospices and 22 nominated significant others participated in a total of 58 interviews. Results: Thematic analysis revealed 4 main themes and 11 subthemes. The main themes were ‘Dependence dichotomy’, ‘In it together’, ‘Biographical uncertainty’, and ‘Conserving integrity’. These themes helped to establish the nature of relationship transitions that the young adult participants from the study experienced and additionally allowed insight into their possible needs at their end of life. Conclusion: This study has identified the nature of relationship transitions pertinent to young adults and has highlighted associated end of life clinical needs. This study can influence further research into the transitions and end of life needs of this particular patient group receiving palliative care, while informing the lacking evidence base which exists internationally. PMID:27781097

Unfinalisability and the authorship of life - Narratives of young-old women from Taiwan.

PubMed

Kok, Jin Kuan; Li, Ming-Chin

2017-08-01

This study investigates and presents the narratives of Taiwanese women who have reached the young-old stage. The narrative interview method was used for data collection from 12 Taiwanese women. After analysing the recurring themes emerging from the women's life histories, it is found that the meanings of these Taiwanese women's narratives could not be finalised according to traditional Confucian norms. These women rebelled, resisted, and resumed authorship to make changes to their lives in a patriarchal society. The women were reflexive, and had constant struggles. The findings also reveal a prominent characteristic of Taiwanese culture that emphasises relationships. The women were able to pursue their dreams to involve themselves in self-care, leisure, aesthetic activities, and classes for their personal growth and pleasure. Copyright © 2017 Elsevier Inc. All rights reserved.

Migration and HIV risk: Life histories of Mexican-born men living with HIV in North Carolina

PubMed Central

Mann, Lilli; Valera, Erik; Hightow-Weidman, Lisa B.; Barrington, Clare

2015-01-01

Latino men in the Southeastern USA are disproportionately affected by HIV, but little is known about how the migration process influences HIV-related risk. In North Carolina (NC), a relatively new immigrant destination, Latino men are predominantly young and from Mexico. We conducted 31 iterative life history interviews with 15 Mexican-born men living with HIV. We used holistic content narrative analysis methods to examine HIV vulnerability in the context of migration and to identify important turning points. Major themes included the prominence of traumatic early life experiences, migration as an ongoing process rather than a finite event, and HIV diagnosis as a final turning point in migration trajectories. Findings provide a nuanced understanding of HIV vulnerability throughout the migration process and have implications including the need for bi-national HIV prevention approaches, improved outreach around early testing and linkage to care, and attention to mental health. PMID:24866206

Generation time, life history and the substitution rate of neutral mutations.

PubMed

Lehtonen, Jussi; Lanfear, Robert

2014-11-01

Our understanding of molecular evolution is hampered by a lack of quantitative predictions about how life-history (LH) traits should correlate with substitution rates. Comparative studies have shown that neutral substitution rates vary substantially between species, and evidence shows that much of this diversity is associated with variation in LH traits. However, while these studies often agree, some unexplained and contradictory results have emerged. Explaining these results is difficult without a clear theoretical understanding of the problem. In this study, we derive predictions for the relationships between LH traits and substitution rates in iteroparous species by using demographic theory to relate commonly measured life-history traits to genetic generation time, and by implication to neutral substitution rates. This provides some surprisingly simple explanations for otherwise confusing patterns, such as the association between fecundity and substitution rates. The same framework can be applied to more complex life histories if full life-tables are available. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Development and Validation of the Health Competence Beliefs Inventory in Young Adults With and Without a History of Childhood Cancer

PubMed Central

DeRosa, Branlyn Werba; Doshi, Kinjal; Schwartz, Lisa A.; Ginsberg, Jill; Mao, Jun J.; Straton, Joseph; Hobbie, Wendy; Rourke, Mary T.; Carlson, Claire; Ittenbach, Richard F.

2012-01-01

Background Adolescent and young adult survivors of childhood cancer are a vulnerable population. Health beliefs may be related to necessary follow-up care. Purpose This study seeks to develop a measure of health beliefs for adolescents and young adults with and without a history of cancer. Methods Inductive and deductive methods and focus groups were used to develop the Health Competence Beliefs Inventory. Cancer survivors (n=138) and comparison participants (n=130) completed the Health Competence Beliefs Inventory and other measures. Healthcare providers reported current medical problems. Results A series of iterative exploratory factor analyses generated a 21-item four-factor solution: (1) Health Perceptions; (2) Satisfaction with Healthcare; (3) Cognitive Competence; and (4) Autonomy. Survivors reported significantly different Health Competence Beliefs Inventory scale scores than comparisons (p<.05). The Health Competence Beliefs Inventory was associated with beliefs, affect, quality of life, posttraumatic stress symptoms, and medical problems. Conclusions The Health Competence Beliefs Inventory is a promising measure of adolescent and young adult perceptions of health and well-being. PMID:20936390

The Impact of Motherhood on the Career Pattern of Working Women: Differences in the Life Histories and Career Status of Employed Mothers and Working Women without Children.

ERIC Educational Resources Information Center

Owings, Jeffrey A.; And Others

A study compared employed mothers with working women who do not have children along dimensions reflective of their life histories and labor market experiences. It utilized data from two nationwide longitudinal surveys--the National Longitudinal Survey of Young Women aged 14 to 24 and the National Longitudinal Study of the High School Class of…

Consilience and Life History Theory: From Genes to Brain to Reproductive Strategy

ERIC Educational Resources Information Center

Figueredo, Aurelio Jose; Vasquez, Geneva; Brumbach, Barbara H.; Schneider, Stephanie M. R.; Sefcek, Jon A.; Tal, Ilanit R.; Hill, Dawn; Wenner, Christopher J.; Jacobs, W. Jake

2006-01-01

We describe an integrated theory of individual differences that traces the behavioral development of life history from genes to brain to reproductive strategy. We provide evidence that a single common factor, the K-Factor, underpins a variety of life-history parameters, including an assortment of sexual, reproductive, parental, familial, and…

[Evaluation of quality of life in school children with a history of early severe malnutrition].

PubMed

De Grandis, E S; Armelini, P A; Cuestas, E

2014-12-01

Severe malnutrition in young children may lead to long-term complications, in particular learning and psychosocial disorders linked to health related quality of life (HRQOL). The aim of this study was to evaluate HRQOL in children whit a history of severe malnutrition before 2 years of life, expecting to find lower scores in these patients. A comparative study was performed on schoolchildren between 5 and 12 years with a history of early severe malnutrition, excluding those with chronic diseases. The Controls were healthy siblings of patients. The sample size was estimated as 26 subjects per group (Total=52). Sociodemographic variables were recorded and the HRQOL was assessed with PedsQL4.0. Chi square and Student t test were applied. Significance level: P<.05. A total of 25 patients and 28 controls were studied. The HRQOL scores obtained from PedsQL for children with history of malnutrition, compared with their healthy siblings, were: Total: 80.82±1.94 vs 89.18±1.84 P<.0001), physical health/dimension: 87.75±3.37 vs 94.75±1.87 (P<.0001), psychosocial health: 77.77±2.90 vs 86.57±1.42 (P<.0001), emotional dimension: 67.80±4.40 vs 78.75±2.96 (P<.0001), social dimension: 88.80±3.05 vs 95.71±1.52 (P<.0001), and school dimension: 74.58±3.80 vs 85.00±3.51 (P<.0001). Patients with a history of early severe malnutrition, showed significantly lower HRQOL scores compared with controls. Copyright © 2013 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

Brief Self-Report Scales Assessing Life History Dimensions of Mating and Parenting Effort.

PubMed

Kruger, Daniel J

2017-01-01

Life history theory (LHT) is a powerful evolutionary framework for understanding physiological, psychological, and behavioral variation both between and within species. Researchers and theorists are increasingly integrating LHT into evolutionary psychology, as it provides a strong foundation for research across many topical areas. Human life history variation has been represented in psychological and behavioral research in several ways, including indicators of conditions in the developmental environment, indicators of conditions in the current environment, and indicators of maturation and life milestones (e.g., menarche, initial sexual activity, first pregnancy), and in self-report survey scale measures. Survey scale measures have included constructs such as time perspective and future discounting, although the most widely used index is a constellation of indicators assessing the K-factor, thought to index general life history speed (from fast to slow). The current project examined the utility of two brief self-report survey measures assessing the life history dimensions of mating effort and parenting effort with a large undergraduate sample in the United States. Consistent with the theory, items reflected two inversely related dimensions. In regressions including the K-factor, the Mating Effort Scale proved to be a powerful predictor of other constructs and indicators related to life history variation. The Parenting Effort Scale had less predictive power overall, although it explained unique variance across several constructs and was the only unique predictor of the number of long-term (serious and committed) relationships. These scales may be valuable additions to self-report survey research projects examining life history variation.

Ecological volatility and human evolution: a novel perspective on life history and reproductive strategy.

PubMed

Wells, Jonathan C K

2012-11-01

Humans are characterized by a suite of traits that seem to differentiate them profoundly from closely related apes such as the gorilla, chimpanzee, and orang-utan. These traits include longevity, cooperative breeding, stacking of offspring, lengthy maturation, and a complex life-course profile of adiposity. When, how, and why these traits emerged during our evolutionary history is currently attracting considerable attention. Most approaches to life history emphasize dietary energy availability and the risk of mortality as the two key stresses shaping life-history variability between and within species. The high energy costs of the large Homo brain are also seen as the central axis around which other life-history traits were reorganized. I propose that ecological volatility may have been a key stress, selecting in favor of the suite of traits in order to tolerate periods of energy scarcity, and increase reproductive output during periods of good conditions. Theses life-history adaptations may have preceded and enabled the trend toward encephalization. Copyright © 2012 Wiley Periodicals, Inc.

Predicting responses to climate change requires all life-history stages.

PubMed

Zeigler, Sara

2013-01-01

In Focus: Radchuk, V., Turlure, C. & Schtickzelle, N. (2013) Each life stage matters: the importance of assessing response to climate change over the complete life cycle in butterflies. Journal of Animal Ecology, 82, 275-285. Population-level responses to climate change depend on many factors, including unexpected interactions among life history attributes; however, few studies examine climate change impacts over complete life cycles of focal species. Radchuk, Turlure & Schtickzelle () used experimental and modelling approaches to predict population dynamics for the bog fritillary butterfly under warming scenarios. Although they found that warming improved fertility and survival of all stages with one exception, populations were predicted to decline because overwintering larvae, whose survival declined with warming, were disproportionately important contributors to population growth. This underscores the importance of considering all life history stages in analyses of climate change's effects on population dynamics. © 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society.

Stressful Life Events, Sexual Orientation, and Cardiometabolic Risk Among Young Adults in the United States

PubMed Central

Hatzenbuehler, Mark L.; Slopen, Natalie; McLaughlin, Kate A.

2015-01-01

Objective The goal of the present study was to examine whether sexual minority young adults are more vulnerable to developing cardiometabolic risk following exposure to stressful life events than heterosexual young adults. Method Data came from the National Longitudinal Study for Adolescent Health (Shin, Edwards, & Heeren, 2009; Brummett et al., 2013), a prospective nationally representative study of U.S. adolescents followed into young adulthood. A total of 306 lesbian, gay, and bisexual (LGB) respondents and 6,667 heterosexual respondents met inclusion criteria for this analysis. Measures of cumulative stressful life events were drawn from all 4 waves of data collection; sexual orientation and cardiometabolic biomarkers were assessed at Wave 4 (2008–2009). Results Gay/bisexual men exposed to 1–2 (β = 0.71, p = .01) and 5 + (β = 0.87, p = .01) stressful life events had a statistically significant elevation in cardiometabolic risk, controlling for demographics, health behaviors, and socioeconomic status. Moreover, in models adjusted for all covariates, lesbian/bisexual (β = 0.52, p = .046) women with 5 + stressful life events had a statistically significant elevation in cardiometabolic risk. There was no relationship between stressful life events and cardiometabolic risk among heterosexual men or women. Conclusion Stressful life events during childhood, adolescence, and young adulthood place LGB young adults at heightened risk for elevated cardiometabolic risk as early as young adulthood. The mechanisms underlying this relationship require future study. PMID:25133830

Material security, life history, and moralistic religions: A cross-cultural examination

PubMed Central

Ross, Cody T.; Apicella, Coren; Atkinson, Quentin D.; Cohen, Emma; McNamara, Rita Anne; Willard, Aiyana K.; Xygalatas, Dimitris; Norenzayan, Ara; Henrich, Joseph

2018-01-01

Researchers have recently proposed that “moralistic” religions—those with moral doctrines, moralistic supernatural punishment, and lower emphasis on ritual—emerged as an effect of greater wealth and material security. One interpretation appeals to life history theory, predicting that individuals with “slow life history” strategies will be more attracted to moralistic traditions as a means to judge those with “fast life history” strategies. As we had reservations about the validity of this application of life history theory, we tested these predictions with a data set consisting of 592 individuals from eight diverse societies. Our sample includes individuals from a wide range of traditions, including world religions such as Buddhism, Hinduism and Christianity, but also local traditions rooted in beliefs in animism, ancestor worship, and worship of spirits associated with nature. We first test for the presence of associations between material security, years of formal education, and reproductive success. Consistent with popular life history predictions, we find evidence that material security and education are associated with reduced reproduction. Building on this, we then test whether or not these demographic factors predict the moral concern, punitiveness, attributed knowledge-breadth, and frequency of ritual devotions towards two deities in each society. Here, we find no reliable evidence of a relationship between number of children, material security, or formal education and the individual-level religious beliefs and behaviors. We conclude with a discussion of why life-history theory is an inadequate interpretation for the emergence of factors typifying the moralistic traditions. PMID:29513766

Positive Psychology: Transforming Young Lives

ERIC Educational Resources Information Center

Brendtro, Larry K.; Mitchell, Martin L.

2011-01-01

To reach responsible independence, young people must become invested in setting their life course. A rich history of research and practice shows that democratic group climates foster autonomy and prosocial behavior. This article explores principles and practices for creating positive peer cultures to develop strengths and help youth meet their…

Gender, sexuality and the participatory dimensions of a comparative life history policy study.

PubMed

Macdonnell, Judith A

2011-12-01

Gender, sexuality and the participatory dimensions of a comparative life history policy study In this paper, I explore how a critical feminist lens was a crucial element in creating a participatory policy study which used a qualitative design and comparative life history methodology. This study focused on Canadian nurses' political practice related to advocacy for lesbian health. Findings show that the combination of the gender lens and life history approach offers potential to create knowledge in ways aligned with health-promoting and emancipatory outcomes. However, the nature of participation and interaction by researcher and participants is contexualized and contested given complex dynamics of power that shape all aspects of this doctoral study process. The critical feminist lens with its focus on reflexivity informed the content and process of knowledge production in this study and shaped key turning points: the ways in which this policy study was conceptualized, the choice of comparative life history methodology, ethical considerations, data collection and analysis and representation of findings. Life history is unlikely to be the methodology that first comes to mind when undertaking a policy study. Its historical roots are associated with biographical, oral history and narrative approaches, which typically aim to elicit understanding of lived experience. Yet, it was this very aspect, this focus on lived experience, which rendered life history methodology fitting as I contemplated how to examine the relationship between nurses and policy. I was interested in understanding nurses' political practice, how policy influenced nurses' capacity to advocate in their everyday lives, as well as nurses' impacts on policy processes and their larger social worlds. © 2011 Blackwell Publishing Ltd.

BRIDGING SCALES IN THE EVOLUTION OF INFECTIOUS DISEASE LIFE HISTORIES: APPLICATION

PubMed Central

Mideo, Nicole; Nelson, William A.; Reece, Sarah E.; Bell, Andrew S.; Read, Andrew F.; Day, Troy

2014-01-01

Within- and between-host disease processes occur on the same timescales, therefore changes in the within-host dynamics of parasites, resources, and immunity can interact with changes in the epidemiological dynamics to affect evolutionary outcomes. Consequently, studies of the evolution of disease life histories, that is, infection-age-specific patterns of transmission and virulence, have been constrained by the need for a mechanistic understanding of within-host disease dynamics. In a companion paper (Day et al. 2011), we develop a novel approach that quantifies the relevant within-host aspects of disease through genetic covariance functions. Here, we demonstrate how to apply this theory to data. Using two previously published datasets from rodent malaria infections, we show how to translate experimental measures into disease life-history traits, and how to quantify the covariance in these traits. Our results show how patterns of covariance can interact with epidemiological dynamics to affect evolutionary predictions for disease life history. We also find that the selective constraints on disease life-history evolution can vary qualitatively, and that “simple” virulence-transmission trade-offs that are often the subject of experimental investigation can be obscured by trade-offs within one trait alone. Finally, we highlight the type and quality of data required for future applications. PMID:22023593

Masked expression of life-history traits in a highly variable environment

USGS Publications Warehouse

DeBoer, Jason A.; Fontaine, Joseph J.; Chizinski, Christopher J.; Pope, Kevin L.

2015-01-01

Differing life-history strategies may act as a constraint on reproductive expression that ultimately limits the ability of individual species to respond to changes in the magnitude or frequency of environmental variation, and potentially underlies the variation often inherent in phenotypic and evolved responses to anthropogenic change. Alternatively, if there are environmental cues that predict reproductive potential, differential expression of life-history strategies may represent differences in the adaptive capacity to optimize current reproductive value given variation in environmental conditions. We compared several aspects of walleye Sander vitreus spawning ecology at two reservoirs that differ in environmental variability (i.e., annual water-level fluctuation) to identify the capacity of phenotypic expression and the corresponding association with age. Despite significant differences in female body and liver masses between reservoirs that differ in environmental variability, we found no difference in reproductive investment measured by egg size and fecundity. Walleye in a highly variable environment appear to exhibit reproductive traits more typical of a short-lived life-history strategy, which may be resultant from the interaction of environmental and anthropogenic pressures. This finding emphasizes the need to identify the degree to which life-history expression represents physiological constraints versus ecological optimization, particularly as anthropogenic change continues to alter environmental conditions. 

Breast cancer, psychological distress and life events among young women

PubMed Central

Peled, Ronit; Carmil, Devora; Siboni-Samocha, Orly; Shoham-Vardi, Ilana

2008-01-01

Since 1983, studies have suggested an interaction between the severe life events, psychological distress and the etiology of Cancer. However, these associations are still under dispute. The aim of the present study was to examine the relationship between life events, psychological distress and Breast Cancer (BC) among young women. Methods A case control study. The study population included 622 women, under the age of 45 years. 255 were diagnosed for BC, and 367 were healthy women. A validated Brief Symptom Inventory (BSI) and Life Event Questionnaire were used. Results The cases presented significantly higher scores of depression compared to the controls and significant lower scores of happiness and optimism. A significant difference was found when comparing the groups according to the cumulative number of life events (two or more events). A multivariate analysis suggest that exposure to more than one life event is positively associated with BC [Odds Ratio(OR) :1.62 95% Confidence Interval (CI): 1.09–2.40], and that a general feeling of happiness and optimism has a "protective effect" on the etiology of BC. (OR-0.75, 95% CI:0.64–0.86). Conclusion Young women who were exposed to a number of life events, should be considered as a risk group for BC and treated accordingly. PMID:18721454

Factors influencing young adults' attitudes and knowledge of late-life sexuality among older women.

PubMed

Allen, Rebecca S; Petro, Kathryn N; Phillips, Laura L

2009-03-01

Although sexuality is valued throughout the lifespan, older women's sexual expression can be influenced by physical, mental and social factors, including attitudes and stereotypes held by younger generations. By gaining an understanding of what influences negative attitudes toward sexuality and beliefs about sexual consent capacity, the stigma associated with sexuality in late life may be reduced. Using vignette methodology in an online survey, we examined older women's health and young adults' (N = 606; mean age = 18.86, SD = 1.42, range 17-36) general knowledge and attitudes toward aging and sexuality, personal sexual behavior, religious beliefs and perceived closeness with an older adult on attitudes towards sexual behavior and perceptions of consent capacity among older women. The health status of older women proved important in determining young adults' acceptance and perception of sexual consent capacity regarding late-life heterosexual/autoerotic and homosexual behaviors. Specifically, young adults expressed lower acceptance and more doubt regarding capacity to consent to sexual expression when the older woman was described as cognitively impaired. Additionally, young adults' personal attitudes toward late-life sexuality, but not knowledge, predicted acceptance toward sexual expression and belief in sexual consent capacity. Attention toward the influence of older women's cognitive health and young adults' attitudes toward late-life sexuality may prove beneficial in designing interventions to decrease the stigma associated with sexual activity in later life.

Does encephalization correlate with life history or metabolic rate in Carnivora?

PubMed

Finarelli, John A

2010-06-23

A recent analysis of brain size evolution reconstructed the plesiomorphic brain-body size allometry for the mammalian order Carnivora, providing an important reference frame for comparative analyses of encephalization (brain volume scaled to body mass). I performed phylogenetically corrected regressions to remove the effects of body mass, calculating correlations between residual values of encephalization with basal metabolic rate (BMR) and six life-history variables (gestation time, neonatal mass, weaning time, weaning mass, litter size, litters per year). No significant correlations were recovered between encephalization and any life-history variable or BMR, arguing against hypotheses relating encephalization to maternal energetic investment. However, after correcting for clade-specific adaptations, I recovered significant correlations for several variables, and further analysis revealed a conserved carnivoran reproductive strategy, linking degree of encephalization to the well-documented mammalian life-history trade-off between neonatal mass and litter size. This strategy of fewer, larger offspring correlating with increased encephalization remains intact even after independent changes in encephalization allometries in the evolutionary history of this clade.

Does encephalization correlate with life history or metabolic rate in Carnivora?

PubMed Central

Finarelli, John A.

2010-01-01

A recent analysis of brain size evolution reconstructed the plesiomorphic brain–body size allometry for the mammalian order Carnivora, providing an important reference frame for comparative analyses of encephalization (brain volume scaled to body mass). I performed phylogenetically corrected regressions to remove the effects of body mass, calculating correlations between residual values of encephalization with basal metabolic rate (BMR) and six life-history variables (gestation time, neonatal mass, weaning time, weaning mass, litter size, litters per year). No significant correlations were recovered between encephalization and any life-history variable or BMR, arguing against hypotheses relating encephalization to maternal energetic investment. However, after correcting for clade-specific adaptations, I recovered significant correlations for several variables, and further analysis revealed a conserved carnivoran reproductive strategy, linking degree of encephalization to the well-documented mammalian life-history trade-off between neonatal mass and litter size. This strategy of fewer, larger offspring correlating with increased encephalization remains intact even after independent changes in encephalization allometries in the evolutionary history of this clade. PMID:20007169

Effects of (un)employment on young couples' health and life satisfaction.

PubMed

Haid, Marja-Lena; Seiffge-Krenke, Inge

2013-01-01

This study investigated effects of employed and unemployed job status on health outcomes with questionnaires in 50 young couples. Analysis of variance revealed higher pessimism, higher stress levels, and lower life satisfaction in couples in which one partner was unemployed. These couples also exhibited more health risk behaviours compared to couples in which both partners were working. The dyadic analysis of data, using an actor-partner interdependence model, demonstrated strong actor and partner effects for male partner's job status. Being unemployed was significantly associated not only with male partner's life satisfaction but also with the life satisfaction of his female partner. In addition, male partner's pessimism was identified as a significant variable which mediates between male partner's job status and female partner's life satisfaction. The study highlights the relevance of the accomplishment of tasks in the domains of work and partnership during young adulthood and it emphasises the gender specific importance.

Biologic History and the Cardinal Rule of Life

NASA Astrophysics Data System (ADS)

Schopf, J. W.

2004-12-01

In broad perspective, the history of life is remarkably static -- once set, a system that has changed little over all of geological time. The basic chemistry of living systems (CHONSP, and the monomers and polymers they compose), the genetics and cellular structure of life, even the ecologic division of the biologic world into "eaters" (heterotrophs) and "eatees" (autotrophs), are innovations all dating from the Archean that have carried over to the present. Throughout Earth history, biology has followed the Cardinal Rule of Life -- avoid change, never evolve at all! Biology maintains the status quo, opportunistically responding only if conditions change. Life's credo might well be "if it ain't broken, don't fix it." Of course, biomolecules do get "broken," by mutations, but living systems have many biochemical repair mechanisms. Evolution is a result of small changes that slip through unfixed. We see the results of evolution in the fossil record only because of the vastness, the true enormity, of geological time. What events punctuated this static underpinning to produce the modern living world? Only three, each in its own way shaping the course of life's history. The earliest, photosynthesis, freed life from dependence on foodstuffs made by nonbiologic processes. The advent of the advanced form of this process, oxygenic ("green plant") photosynthesis -- also an Archean innovation -- pumped oxygen into the environment (markedly increasing energy yields), "rusted the Earth" (evidenced by banded iron-formations), and, by ˜2,300 Ma ago, led to establishment of an aerobic-anaerobic ecosystem like that today. Not surprisingly, given the Cardinal Rule of Life, the inventors of this innovation, microbial cyanobacteria, evolved little over billions of years. The second major innovation was sex. In the modern world, this reproductive process is exhibited only by nucleated (eukaryotic) cells, derived from non-sexual eukaryotic ancestors. Although eukaryotes date from ˜2

Dysmenorrhea: Prevalence and Impact on Quality of Life among Young Adult Jordanian Females.

PubMed

Al-Jefout, Moamar; Seham, Abu-Fraijeh; Jameel, Hijazeen; Randa, Al-Qaisi; Ola, Al-Ma'aitah; Oday, Al-Ma'aitah; Luscombe, Georgina

2015-06-01

To establish the prevalence and impact on quality of life of dysmenorrhea among young adult Jordanian females. Cross-sectional study based on quantitative self-reported anonymous questionnaire. University-based study. A total of 272 female medical students (aged 19-25 years). None. Self-reports of menstruation-related pain symptoms and methods of dealing with them. Of study subjects 152/272 (55.8%) participants had moderate and severe dysmenorrhea. Of them, 55.8% had a family history of severe dysmenorrhea compared with 33.1% of those without dysmenorrhea (χ2 = 13.40, df = 1, P < .001). There was strong association between severity of dysmenorrhea and poor university attendance (χ(2) = 45.35, df = 2, P < .001), poor social activities (χ2 = 32.06, df = 2, P < .001), poor relationships with family (χ2 = 18.46, df = 2, P < .001) and friends (χ2 = 19.14, df = 2, P < .001), and poor sport activities (χ2 = 12.15, df = 2, P = .002). Dysmenorrhea worsens during examination periods in 50% of cases. The most common pain symptom was low back pain (60.2%). Body mass index, family monthly income and early age at menarche had no correlation with the occurrence of dysmenorrhea. Of those with dysmenorrhea, 69.4% were using analgesics. Mothers were the main source of information regarding menstruation. Dysmenorrhea is highly prevalent among young adult Jordanian females and seems to negatively affect quality of life, particularly as related to university attendance and performance and social relationships. Copyright © 2015 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

Young People's Life-Skills and the Future. Research Report Series.

ERIC Educational Resources Information Center

Powney, Janet; Lowden, Kevin; Hall, Stuart

A study investigated what Scottish and English young people consider important life skills, how they believe they develop them, and how necessary they see them to their future lives. More than 200 16-21-year-olds examined photographs of events related to basic life tasks, family, close relationships, work or school and leisure activities and then…

Density-dependence interacts with extrinsic mortality in shaping life histories

PubMed Central

Burger, Oskar; Kozłowski, Jan

2017-01-01

The role of extrinsic mortality in shaping life histories is poorly understood. However, substantial evidence suggests that extrinsic mortality interacts with density-dependence in crucial ways. We develop a model combining Evolutionarily Stable Strategies with a projection matrix that allows resource allocation to growth, tissue repairs, and reproduction. Our model examines three cases, with density-dependence acting on: (i) mortality, (ii) fecundity, and (iii) production rate. We demonstrate that density-independent extrinsic mortality influences the rate of aging, age at maturity, growth rate, and adult size provided that density-dependence acts on fertility or juvenile mortality. However, density-independent extrinsic mortality has no effect on these life history traits when density-dependence acts on survival. We show that extrinsic mortality interacts with density-dependence via a compensation mechanism: the higher the extrinsic mortality the lower the strength of density-dependence. However, this compensation fully offsets the effect of extrinsic mortality only if density-dependence acts on survival independently of age. Both the age-pattern and the type of density-dependence are crucial for shaping life history traits. PMID:29049399

Life-history evolution and the microevolution of intermediary metabolism: activities of lipid-metabolizing enzymes in life-history morphs of a wing-dimorphic cricket.

PubMed

Zera, Anthony J; Zhao, Zhangwu

2003-03-01

Although a considerable amount of information is available on the ecology, genetics, and physiology of life-history traits, much more limited data are available on the biochemical and genetic correlates of life-history variation within species. Specific activities of five enzymes of lipid biosynthesis and two enzymes of amino acid catabolism were compared among lines selected for flight-capable (LW[f]) versus flightless (SW) morphs of the cricket Gryllus firmus. These morphs, which exist in natural populations, differ genetically in ovarian growth (100-400% higher in SW) and aspects of flight capability including the size of wings and flight muscles, and the concentration of triglyceride flight fuel (40% greater in LW[f]). Consistently higher activity of each enzyme in LW(f) versus SW-selected lines, and strong co-segregation between morph and enzyme activity, demonstrated genetically based co-variance between wing morph and enzyme activity. Developmental profiles of enzyme activities strongly paralleled profiles of triglyceride accumulation during adulthood and previous measures of in vivo lipid biosynthesis. These data strongly imply that genetically based elevation in activities of lipogenic enzymes, and enzymes controlling the conversion of amino acids into lipids, is an important cause underlying the elevated accumulation of triglyceride in the LW(f) morph, a key biochemical component of the trade-off between elevated early fecundity and flight capability. Global changes in lipid and amino-acid metabolism appear to have resulted from microevolutionary alteration of regulators of metabolism. Finally, strong genotype x environment (diet) interactions were observed for most enzyme activities. Future progress in understanding the functional causes of life-history evolution requires a more detailed synthesis of the fields of life-history evolution and metabolic biochemistry. Wing polymorphism is a powerful experimental model in such integrative studies.

Individual heterogeneity in life histories and eco-evolutionary dynamics

PubMed Central

Vindenes, Yngvild; Langangen, Øystein

2015-01-01

Individual heterogeneity in life history shapes eco-evolutionary processes, and unobserved heterogeneity can affect demographic outputs characterising life history and population dynamical properties. Demographic frameworks like matrix models or integral projection models represent powerful approaches to disentangle mechanisms linking individual life histories and population-level processes. Recent developments have provided important steps towards their application to study eco-evolutionary dynamics, but so far individual heterogeneity has largely been ignored. Here, we present a general demographic framework that incorporates individual heterogeneity in a flexible way, by separating static and dynamic traits (discrete or continuous). First, we apply the framework to derive the consequences of ignoring heterogeneity for a range of widely used demographic outputs. A general conclusion is that besides the long-term growth rate lambda, all parameters can be affected. Second, we discuss how the framework can help advance current demographic models of eco-evolutionary dynamics, by incorporating individual heterogeneity. For both applications numerical examples are provided, including an empirical example for pike. For instance, we demonstrate that predicted demographic responses to climate warming can be reversed by increased heritability. We discuss how applications of this demographic framework incorporating individual heterogeneity can help answer key biological questions that require a detailed understanding of eco-evolutionary dynamics. PMID:25807980

Seed after-ripening and dormancy determine adult life history independently of germination timing.

PubMed

de Casas, Rafael Rubio; Kovach, Katherine; Dittmar, Emily; Barua, Deepak; Barco, Brenden; Donohue, Kathleen

2012-05-01

• Seed dormancy can affect life history through its effects on germination time. Here, we investigate its influence on life history beyond the timing of germination. • We used the response of Arabidopsis thaliana to chilling at the germination and flowering stages to test the following: how seed dormancy affects germination responses to the environment; whether variation in dormancy affects adult phenology independently of germination time; and whether environmental cues experienced by dormant seeds have an effect on adult life history. • Dormancy conditioned the germination response to low temperatures, such that prolonged periods of chilling induced dormancy in nondormant seeds, but stimulated germination in dormant seeds. The alleviation of dormancy through after-ripening was associated with earlier flowering, independent of germination date. Experimental dormancy manipulations showed that prolonged chilling at the seed stage always induced earlier flowering, regardless of seed dormancy. Surprisingly, this effect of seed chilling on flowering time was observed even when low temperatures did not induce germination. • In summary, seed dormancy influences flowering time and hence life history independent of its effects on germination timing. We conclude that the seed stage has a pronounced effect on life history, the influence of which goes well beyond the timing of germination. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

"It's Not Much of a Life": The Benefits and Ethics of Using Life History Methods With People Who Inject Drugs in Qualitative Harm Reduction Research.

PubMed

Harris, Magdalena; Rhodes, Tim

2018-06-01

A life history approach enables study of how risk or health protection is shaped by critical transitions and turning points in a life trajectory and in the context of social environment and time. We employed visual and narrative life history methods with people who inject drugs to explore how hepatitis C protection was enabled and maintained over the life course. We overview our methodological approach, with a focus on the ethics in practice of using life history timelines and life-grids with 37 participants. The life-grid evoked mixed emotions for participants: pleasure in receiving a personalized visual history and pain elicited by its contents. A minority managed this pain with additional heroin use. The methodological benefits of using life history methods and visual aids have been extensively reported. Crucial to consider are the ethical implications of this process, particularly for people who lack socially ascribed markers of a "successful life."

New perspectives in the history of twentieth-century life sciences: historical, historiographical and epistemological themes.

PubMed

Meunier, Robert; Nickelsen, Kärin

2018-01-18

The history of twentieth-century life sciences is not exactly a new topic. However, in view of the increasingly rapid development of the life sciences themselves over the past decades, some of the well-established narratives are worth revisiting. Taking stock of where we stand on these issues was the aim of a conference in 2015, entitled "Perspectives for the History of Life Sciences" (Munich, Oct 30-Nov 1, 2015). The papers in this topical collection are based on work presented and discussed at and around this meeting. Just as the conference, the collection aims at exploring fields in the history of life sciences that appear understudied, sources that have been overlooked, and novel ways of engaging with this material. The papers convened in this collection may not be representative of the field as a whole; but we feel that they do indicate some elements that have received emphasis in recent years, and may become more central in the years to come, such as the history of previously neglected contexts and domains of the life sciences, the question of continuity and change on the level of practices, the history of complexity and diversity in twentieth-century life sciences and the reconsideration of the relationship between history and philosophy of life sciences.

Hormonal correlates of male life history stages in wild white-faced capuchin monkeys (Cebus capucinus)

PubMed Central

Jack, Katharine M.; Schoof, Valérie A.M.; Sheller, Claire R.; Rich, Catherine I.; Klingelhofer, Peter P.; Ziegler, Toni E.; Fedigan, Linda

2014-01-01

Much attention has been paid to hormonal variation in relation to male dominance status and reproductive seasonality, but we know relatively little about how hormones vary across life history stages. Here we examine fecal testosterone (fT), dihydrotestosterone (fDHT), and glucocorticoid (fGC) profiles across male life history stages in wild white-faced capuchins (Cebus capucinus). Study subjects included 37 males residing in three habituated social groups in the Área de Conservacíon Guanacaste, Costa Rica. Male life history stages included infant (0 to <12 months; N = 3), early juvenile (1 to <3 years; N = 10), late juvenile (3 to <6 years; N = 9), subadult (6 to <10 years; N = 8), subordinate adult (≥10 years; N = 3), and alpha adult (≥ 10 years; N = 4, including one recently deposed alpha). Life history stage was a significant predictor of fT; levels were low throughout the infant and juvenile phases, doubled in subadult and subordinate adults, and were highest for alpha males. Life history stage was not a significant predictor of fDHT, fDHT:fT, or fGC levels. Puberty in white-faced capuchins appears to begin in earnest during the subadult male phase, indicated by the first significant rise in fT. Given their high fT levels and exaggerated secondary sexual characteristics, we argue that alpha adult males represent a distinctive life history stage not experienced by all male capuchins. This study is the first to physiologically validate observable male life history stages using patterns of hormone excretion in wild Neotropical primates, with evidence for a strong association between fT levels and life history stage. PMID:24184868

Evolution of reproductive life histories in island birds worldwide

PubMed Central

Covas, Rita

2012-01-01

Island environments typically share characteristics such as impoverished biotas and less-seasonal climates, which should be conducive to specific adaptations by organisms. However, with the exception of morphological studies, broad-scale tests of patterns of adaptation on islands are rare. Here, I examine reproductive patterns in island birds worldwide. Reproductive life histories are influenced by latitude, which could affect the response to insularity; therefore, I additionally test this hypothesis. Island colonizers showed mostly bi-parental care, but there was a significant increase in cooperative breeding on islands. Additionally, I found support for previous suggestions of reduced fecundity, longer developmental periods and increased investment in young on islands. However, clutch size increased with latitude at a rate nearly five times faster on the mainland than on the islands revealing a substantially stronger effect of insularity at higher latitudes. Latitude and insularity may also interact to determine egg volume and incubation periods, but these effects were less clear. Analyses of reproductive success did not support an effect of reduced nest predation as a driver of reproductive change, but this requires further study. The effect of latitude detected here suggests that the evolutionary changes associated with insularity relate to environmental stability and improved adult survival. PMID:22072609

Gifted and Talented Young Women: Antecedents and Correlates of Life Satisfaction.

ERIC Educational Resources Information Center

Hollinger, Constance L.; Fleming, Elyse S.

1988-01-01

The study examined the antecedents and correlates of general life satisfaction as reported by 108 gifted and talented young women. Results of the six-year longitudinal analyses supported the predicted centrality of instrumental self perception to social self esteem, occupational confidence, and general life satisfaction. (Author/DB)

Implications of ecological energetics and biophysical and developmental constraints for life history variation in dinosaurs

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

Dunham, A.E.; Overall, K.L.; Forster, C.A.

1988-01-01

There has been much recent speculation concerning the nature of life history variation in dinosaurs (Case, 1978; Bakker, 1986; Horner, 1982, 1984a). The purpose of this paper is to review the data on dinosaur life histories and to examine the nature and magnitude of the demographic and physiological factors that must have constrained life history variation in this group. 145 refs., 8 figs., 3 tabs.

Bridging scales in the evolution of infectious disease life histories: application.

PubMed

Mideo, Nicole; Nelson, William A; Reece, Sarah E; Bell, Andrew S; Read, Andrew F; Day, Troy

2011-11-01

Within- and between-host disease processes occur on the same timescales, therefore changes in the within-host dynamics of parasites, resources, and immunity can interact with changes in the epidemiological dynamics to affect evolutionary outcomes. Consequently, studies of the evolution of disease life histories, that is, infection-age-specific patterns of transmission and virulence, have been constrained by the need for a mechanistic understanding of within-host disease dynamics. In a companion paper (Day et al. 2011), we develop a novel approach that quantifies the relevant within-host aspects of disease through genetic covariance functions. Here, we demonstrate how to apply this theory to data. Using two previously published datasets from rodent malaria infections, we show how to translate experimental measures into disease life-history traits, and how to quantify the covariance in these traits. Our results show how patterns of covariance can interact with epidemiological dynamics to affect evolutionary predictions for disease life history. We also find that the selective constraints on disease life-history evolution can vary qualitatively, and that "simple" virulence-transmission trade-offs that are often the subject of experimental investigation can be obscured by trade-offs within one trait alone. Finally, we highlight the type and quality of data required for future applications. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.

Linkages between mitochondrial lipids and life history in temperate and tropical birds.

PubMed

Calhoon, Elisabeth A; Jimenez, Ana Gabriela; Harper, James M; Jurkowitz, Marianne S; Williams, Joseph B

2014-01-01

Temperate birds tend to have a fast pace of life and short life spans with high reproductive output, whereas tropical birds tend to have a slower pace of life, invest fewer resources in reproduction, and have higher adult survival rates. How these differences in life history at the organismal level are rooted in differences at the cellular level is a major focus of current research. Here, we cultured fibroblasts from phylogenetically paired tropical and temperate species, isolated mitochondria from each, and compared their mitochondrial membrane lipids. We also correlated the amounts of these lipids with an important life history parameter, clutch size. We found that tropical birds tended to have less mitochondrial lipid per cell, especially less cardiolipin per cell, suggesting that cells from tropical birds have fewer mitochondria or less inner mitochondrial membrane per cell. We also found that the mitochondria of tropical birds and the species with the smallest clutch sizes had higher amounts of plasmalogens, a lipid that could serve as an antioxidant. Overall, our findings are consistent with the idea that there are underlying molecular and cellular physiological traits that could account for the differences in whole-animal physiology between animals with different life histories.

How Metamorphosis Is Different in Plethodontids: Larval Life History Perspectives on Life-Cycle Evolution

PubMed Central

Beachy, Christopher K.; Ryan, Travis J.; Bonett, Ronald M.

2017-01-01

Plethodontid salamanders exhibit biphasic, larval form paedomorphic, and direct developing life cycles. This diversity of developmental strategies exceeds that of any other family of terrestrial vertebrate. Here we compare patterns of larval development among the three divergent lineages of biphasic plethodontids and other salamanders. We discuss how patterns of life-cycle evolution and larval ecology might have produced a wide array of larval life histories. Compared with many other salamanders, most larval plethodontids have relatively slow growth rates and sometimes exceptionally long larval periods (up to 60 mo). Recent phylogenetic analyses of life-cycle evolution indicate that ancestral plethodontids were likely direct developers. If true, then biphasic and paedomorphic lineages might have been independently derived through different developmental mechanisms. Furthermore, biphasic plethodontids largely colonized stream habitats, which tend to have lower productivity than seasonally ephemeral ponds. Consistent with this, plethodontid larvae grow very slowly, and metamorphic timing does not appear to be strongly affected by growth history. On the basis of this, we speculate that feeding schedules and stress hormones might play a comparatively reduced role in governing the timing of metamorphosis of stream-dwelling salamanders, particularly plethodontids. PMID:29269959

Mapping the social determinants of substance use for pregnant-involved young Aboriginal women

PubMed Central

Shahram, Sana Z.; Bottorff, Joan L.; Oelke, Nelly D.; Kurtz, Donna L. M.; Thomas, Victoria; Spittal, Patricia M.

2017-01-01

ABSTRACT There is a dearth of knowledge about the social determinants of substance use among young pregnant-involved Indigenous women in Canada from their perspectives. As part of life history interviews, 17 young pregnant-involved Indigenous women with experiences with substances completed a participant-generated mapping activity CIRCLES (Charting Intersectional Relationships in the Context of Life). As women created their maps, they discussed how different social determinants impacted their experiences with pregnancy and substance use. The social determinants identified and used by women to explain determinants of their substance use were grouped into 10 themes: traumatic life histories; socioeconomic status; culture, identity and spirituality; shame and guilt; mental wellness; family connections; romantic and platonic relationships; strength and hope; mothering; and the intersections of determinants. We conclude that understanding the context and social determinants of substance use from a woman-informed perspective is paramount to informing effective and appropriate programs to support young Indigenous women who use substances. PMID:28140776

Life stress and family history for depression: the moderating role of past depressive episodes.

PubMed

Monroe, Scott M; Slavich, George M; Gotlib, Ian H

2014-02-01

Three of the most consistently reported and powerful predictors of depression are a recent major life event, a positive family history for depression, and a personal history of past depressive episodes. Little research, however, has evaluated the inter-relations among these predictors in depressed samples. Such information is descriptively valuable and potentially etiologically informative. In the present article we summarize the existing literature and test four predictions in a sample of 62 clinically depressed individuals: (1) participants who experienced a major life event prior to onset would be less likely than participants who did not experience a major life event to have a positive family history for depression; (2) participants with a recent major life event would have fewer lifetime episodes of depression than would participants without; (3) participants with a positive family history for depression would have more lifetime episodes of depression than would participants with a negative family history for depression; and (4) we would obtain a 3-way interaction in which participants with a positive family history and without a major life event would have the most lifetime episodes, whereas participants with a negative family history and a major life event would have the fewest lifetime episodes. The first three predictions were confirmed, and the fourth prediction partially confirmed. These novel findings begin to elucidate the complex relations among these three prominent risk factors for depression, and point to avenues of research that may help illuminate the origins of depressive episodes. Copyright © 2013 Elsevier Ltd. All rights reserved.

Functional linkages for the pace of life, life-history, and environment in birds.

PubMed

Williams, Joseph B; Miller, Richard A; Harper, James M; Wiersma, Popko

2010-11-01

For vertebrates, body mass underlies much of the variation in metabolism, but among animals of the same body mass, metabolism varies six-fold. Understanding how natural selection can influence variation in metabolism remains a central focus of Physiological Ecologists. Life-history theory postulates that many physiological traits, such as metabolism, may be understood in terms of key maturational and reproductive characteristics over an organism's life-span. Although it is widely acknowledged that physiological processes serve as a foundation for life-history trade-offs, the physiological mechanisms that underlie the diversification of life-histories remain elusive. Data show that tropical birds have a reduced basal metabolism (BMR), field metabolic rate, and peak metabolic rate compared with temperate counterparts, results consistent with the idea that a low mortality, and therefore increased longevity, and low productivity is associated with low mass-specific metabolic rate. Mass-adjusted BMR of tropical and temperate birds was associated with survival rate, in accordance with the view that animals with a slow pace of life tend to have increased life spans. To understand the mechanisms responsible for a reduced rate of metabolism in tropical birds compared with temperate species, we summarized an unpublished study, based on data from the literature, on organ masses for both groups. Tropical birds had smaller hearts, kidneys, livers, and pectoral muscles than did temperate species of the same body size, but they had a relatively larger skeletal mass. Direct measurements of organ masses for tropical and temperate birds showed that the heart, kidneys, and lungs were significantly smaller in tropical birds, although sample sizes were small. Also from an ongoing study, we summarized results to date on connections between whole-organism metabolism in tropical and temperate birds and attributes of their dermal fibroblasts grown in cell culture. Cells derived from

Primate enamel evinces long period biological timing and regulation of life history.

PubMed

Bromage, Timothy G; Hogg, Russell T; Lacruz, Rodrigo S; Hou, Chen

2012-07-21

The factor(s) regulating the combination of traits that define the overall life history matrix of mammalian species, comprising attributes such as brain and body weight, age at sexual maturity, lifespan and others, remains a complete mystery. The principal objectives of the present research are (1) to provide evidence for a key variable effecting life history integration and (2) to provide a model for how one would go about investigating the metabolic mechanisms responsible for this rhythm. We suggest here that a biological rhythm with a period greater than the circadian rhythm is responsible for observed variation in primate life history. Evidence for this rhythm derives from studies of tooth enamel formation. Enamel contains an enigmatic periodicity in its microstructure called the striae of Retzius, which develops at species specific intervals in units of whole days. We refer to this enamel rhythm as the repeat interval (RI). For primates, we identify statistically significant relationships between RI and all common life history traits. Importantly, RI also correlates with basal and specific metabolic rates. With the exception of estrous cyclicity, all relationships share a dependence upon body mass. This dependence on body mass informs us that some aspect of metabolism is responsible for periodic energy allocations at RI timescales, regulating cell proliferation rates and growth, thus controlling the pace, patterning, and co-variation of life history traits. Estrous cyclicity relates to the long period rhythm in a body mass-independent manner. The mass-dependency and -independency of life history relationships with RI periodicity align with hypothalamic-mediated neurosecretory anterior and posterior pituitary outputs. We term this period the Havers-Halberg Oscillation (HHO), in reference to Clopton Havers, a 17th Century hard tissue anatomist, and Franz Halberg, a long-time explorer of long-period rhythms. We propose a mathematical model that may help elucidate

Life history of the vulnerable endemic crayfish Cambarus (Erebicambarus) maculatus Hobbs and Pflieger, 1988 (Decapoda: Astacoidea: Cambaridae) in Missouri, USA

USGS Publications Warehouse

DiStefano, Robert J.; Westhoff, Jacob T.; Ames, Catlin W.; Rosenberger, Amanda E.

2016-01-01

The vulnerable freckled crayfish, Cambarus maculatus Hobbs and Pflieger, 1988, is endemic to only one drainage in eastern Missouri, USA, which is impacted by heavy metals mining and adjacent to a rapidly-expanding urban area. We studied populations of C. maculatus in two small streams for 25 months to describe annual reproductive cycles, and gather information about fecundity, sex ratio, size at maturity, size-class structure, and growth, capturing a monthly average of more than 50 individuals from each of the two study populations. Information about the density of the species at supplemental sampling streams was also obtained. The species exhibited traits consistent with a K-strategist life history; long-lived, slow-growing, with fewer but larger eggs than sympatric crayfish species. Breeding season occurred in mid- to late autumn, potentially extending into early winter. Egg brooding occurred primarily in May. Young of year were first observed in June. We estimated that these populations contained four to six size-classes, observed smaller individuals grew faster than larger individuals, and most became sexually mature in their second year of life. Densities of C. maculatus were low relative to several sympatric species of Orconectes Cope, 1872. Life history information presented herein will be important for anticipated future conservation efforts.

Young Adult Outcome of Hyperactive Children: Adaptive Functioning in Major Life Activities

ERIC Educational Resources Information Center

Barkley, Russell A.; Fischer, Mariellen; Smallish, Lori; Fletcher, Kenneth

2006-01-01

Objective: The authors report the adaptive functioning of hyperactive and control children in southeastern Wisconsin (Milwaukee) followed to young adulthood. Method: Interviews with participants concerning major life activities were collected between 1992 and 1996 and used along with employer ratings and high school records at the young adult…

Unification theory of optimal life histories and linear demographic models in internal stochasticity.

PubMed

Oizumi, Ryo

2014-01-01

Life history of organisms is exposed to uncertainty generated by internal and external stochasticities. Internal stochasticity is generated by the randomness in each individual life history, such as randomness in food intake, genetic character and size growth rate, whereas external stochasticity is due to the environment. For instance, it is known that the external stochasticity tends to affect population growth rate negatively. It has been shown in a recent theoretical study using path-integral formulation in structured linear demographic models that internal stochasticity can affect population growth rate positively or negatively. However, internal stochasticity has not been the main subject of researches. Taking account of effect of internal stochasticity on the population growth rate, the fittest organism has the optimal control of life history affected by the stochasticity in the habitat. The study of this control is known as the optimal life schedule problems. In order to analyze the optimal control under internal stochasticity, we need to make use of "Stochastic Control Theory" in the optimal life schedule problem. There is, however, no such kind of theory unifying optimal life history and internal stochasticity. This study focuses on an extension of optimal life schedule problems to unify control theory of internal stochasticity into linear demographic models. First, we show the relationship between the general age-states linear demographic models and the stochastic control theory via several mathematical formulations, such as path-integral, integral equation, and transition matrix. Secondly, we apply our theory to a two-resource utilization model for two different breeding systems: semelparity and iteroparity. Finally, we show that the diversity of resources is important for species in a case. Our study shows that this unification theory can address risk hedges of life history in general age-states linear demographic models.

Unification Theory of Optimal Life Histories and Linear Demographic Models in Internal Stochasticity

PubMed Central

Oizumi, Ryo

2014-01-01

Life history of organisms is exposed to uncertainty generated by internal and external stochasticities. Internal stochasticity is generated by the randomness in each individual life history, such as randomness in food intake, genetic character and size growth rate, whereas external stochasticity is due to the environment. For instance, it is known that the external stochasticity tends to affect population growth rate negatively. It has been shown in a recent theoretical study using path-integral formulation in structured linear demographic models that internal stochasticity can affect population growth rate positively or negatively. However, internal stochasticity has not been the main subject of researches. Taking account of effect of internal stochasticity on the population growth rate, the fittest organism has the optimal control of life history affected by the stochasticity in the habitat. The study of this control is known as the optimal life schedule problems. In order to analyze the optimal control under internal stochasticity, we need to make use of “Stochastic Control Theory” in the optimal life schedule problem. There is, however, no such kind of theory unifying optimal life history and internal stochasticity. This study focuses on an extension of optimal life schedule problems to unify control theory of internal stochasticity into linear demographic models. First, we show the relationship between the general age-states linear demographic models and the stochastic control theory via several mathematical formulations, such as path–integral, integral equation, and transition matrix. Secondly, we apply our theory to a two-resource utilization model for two different breeding systems: semelparity and iteroparity. Finally, we show that the diversity of resources is important for species in a case. Our study shows that this unification theory can address risk hedges of life history in general age-states linear demographic models. PMID:24945258

An experimental manipulation of life-history trajectories and resistance to oxidative stress.

PubMed

Alonso-Alvarez, Carlos; Bertrand, Sophie; Devevey, Godefroy; Prost, Josiane; Faivre, Bruno; Chastel, Olivier; Sorci, Gabriele

2006-09-01

Optimal investment into life-history traits depends on the environmental conditions that organisms are likely to experience during their life. Evolutionary theory tells us that optimal investment in reproduction versus maintenance is likely to shape the pattern of age-associated decline in performance, also known as aging. The currency that is traded against different vital functions is, however, still debated. Here, we took advantage of a phenotypic manipulation of individual quality in early life to explore (1) long-term consequences on life-history trajectories, and (2) the possible physiological mechanism underlying the life-history adjustments. We manipulated phenotypic quality of a cohort of captive zebra finches (Taeniopygia guttata) by assigning breeding pairs to either an enlarged or a reduced brood. Nestlings raised in enlarged broods were in poorer condition than nestlings raised in reduced broods. Interestingly, the effect of environmental conditions experienced during early life extended to the age at first reproduction. Birds from enlarged broods delayed reproduction. Birds that delayed reproduction produced less offspring but lived longer, although neither fecundity nor longevity were directly affected by the experimental brood size. Using the framework of the life-table response experiment modeling, we also explored the effect of early environmental condition on population growth rate and aging. Birds raised in reduced broods tended to have a higher population growth rate, and a steeper decrease of reproductive value with age than birds reared in enlarged broods. Metabolic resources necessary to fight off the damaging effect of reactive oxygen species (ROS) could be the mechanism underlying the observed results, as (1) birds that engaged in a higher number of breeding events had a weaker red blood cell resistance to oxidative stress, (2) red blood cell resistance to oxidative stress predicted short-term mortality (but not longevity), and (3) was

Maternal investment, life-history strategy of the offspring and adult chronic disease risk in South Asian women in the UK.

PubMed

Wells, Jonathan C K; Yao, Pallas; Williams, Jane E; Gayner, Rebecca

2016-01-01

Patterns of development predict cardiovascular disease (CVD) risk, and ethnic differences therein, but it remains unclear why apparently 'adaptive plasticity' in early life should generate health costs in later life. We hypothesized that offspring receiving low maternal investment during fetal life, the primary period of organogenesis, should predict a shorter reproductive career and develop a fast life-history strategy, prioritizing reproduction over growth and homeostatic maintenance. We studied 58 young adult South Asian women living in the UK, a group with high susceptibility to CVD. We obtained gestational age, birth weight (BW) and menarcheal age by recall and measured anthropometry, body composition, resting metabolic rate (RMR) and blood pressure (BP). BW and gestational age were inversely associated with menarcheal age, indicating that lower maternal investment is associated with faster maturation. Menarcheal age was positively associated with height but inversely with adiposity, indicating that rapid maturation prioritizes lipid stores over somatic growth. BW was inversely associated with BP, whereas adiposity was positively associated, indicating that lower maternal investment reduces BP homeostasis. BW was positively associated with RMR, whereas menarche was inversely associated, indicating that maternal investment influences adult metabolism. Supporting our hypothesis, low maternal investment promoted faster life histories, demonstrated by earlier menarche, reduced growth and elevated adiposity. These traits were associated with poorer BP regulation. This is the first study demonstrating strategic adjustment of the balance between reproduction and metabolic health in response to the level of maternal investment during fetal life. © The Author(s) 2016. Published by Oxford University Press on behalf of the Foundation for Evolution, Medicine, and Public Health.

Later Life Parental Divorce and Widowhood: Impact on Young Adults' Assessment of Parent-Child Relations.

ERIC Educational Resources Information Center

Aquilino, William S.

1994-01-01

Explored implications of later life parental divorce and widowhood for relationship between parents and young adult children among 3,281 young adults who grew up in intact families. Family disruption that occurred after children were grown had sizable effects on parent-adult child relations, with later life divorce lowering relationship quality…

Immune defense and host life history.

PubMed

Zuk, Marlene; Stoehr, Andrew M

2002-10-01

Recent interest has focused on immune response in an evolutionary context, with particular attention to disease resistance as a life-history trait, subject to trade-offs against other traits such as reproductive effort. Immune defense has several characteristics that complicate this approach, however; for example, because of the risk of autoimmunity, optimal immune defense is not necessarily maximum immune defense. Two important types of cost associated with immunity in the context of life history are resource costs, those related to the allocation of essential but limited resources, such as energy or nutrients, and option costs, those paid not in the currency of resources but in functional or structural components of the organism. Resource and option costs are likely to apply to different aspects of resistance. Recent investigations into possible trade-offs between reproductive effort, particularly sexual displays, and immunity have suggested interesting functional links between the two. Although all organisms balance the costs of immune defense against the requirements of reproduction, this balance works out differently for males than it does for females, creating sex differences in immune response that in turn are related to ecological factors such as the mating system. We conclude that immune response is indeed costly and that future work would do well to include invertebrates, which have sometimes been neglected in studies of the ecology of immune defense.

"Ant" and "grasshopper" life-history strategies in Saccharomyces cerevisiae.

PubMed

Spor, Aymé; Wang, Shaoxiao; Dillmann, Christine; de Vienne, Dominique; Sicard, Delphine

2008-02-13

From the evolutionary and ecological points of view, it is essential to distinguish between the genetic and environmental components of the variability of life-history traits and of their trade-offs. Among the factors affecting this variability, the resource uptake rate deserves particular attention, because it depends on both the environment and the genetic background of the individuals. In order to unravel the bases of the life-history strategies in yeast, we grew a collection of twelve strains of Saccharomyces cerevisiae from different industrial and geographical origins in three culture media differing for their glucose content. Using a population dynamics model to fit the change of population size over time, we estimated the intrinsic growth rate (r), the carrying capacity (K), the mean cell size and the glucose consumption rate per cell. The life-history traits, as well as the glucose consumption rate, displayed large genetic and plastic variability and genetic-by-environment interactions. Within each medium, growth rate and carrying capacity were not correlated, but a marked trade-off between these traits was observed over the media, with high K and low r in the glucose rich medium and low K and high r in the other media. The cell size was tightly negatively correlated to carrying capacity in all conditions. The resource consumption rate appeared to be a clear-cut determinant of both the carrying capacity and the cell size in all media, since it accounted for 37% to 84% of the variation of those traits. In a given medium, the strains that consume glucose at high rate have large cell size and low carrying capacity, while the strains that consume glucose at low rate have small cell size but high carrying capacity. These two contrasted behaviors may be metaphorically defined as "ant" and "grasshopper" strategies of resource utilization. Interestingly, a strain may be "ant" in one medium and "grasshopper" in another. These life-history strategies are discussed

Life-history traits predict perennial species response to fire in a desert ecosystem

PubMed Central

Shryock, Daniel F; DeFalco, Lesley A; Esque, Todd C

2014-01-01

The Mojave Desert of North America has become fire-prone in recent decades due to invasive annual grasses that fuel wildfires following years of high rainfall. Perennial species are poorly adapted to fire in this system, and post-fire shifts in species composition have been substantial but variable across community types. To generalize across a range of conditions, we investigated whether simple life-history traits could predict how species responded to fire. Further, we classified species into plant functional types (PFTs) based on combinations of life-history traits and evaluated whether these groups exhibited a consistent fire-response. Six life-history traits varied significantly between burned and unburned areas in short (up to 4 years) or long-term (up to 52 years) post-fire datasets, including growth form, lifespan, seed size, seed dispersal, height, and leaf longevity. Forbs and grasses consistently increased in abundance after fire, while cacti were reduced and woody species exhibited a variable response. Woody species were classified into three PFTs based on combinations of life-history traits. Species in Group 1 increased in abundance after fire and were characterized by short lifespans, small, wind-dispersed seeds, low height, and deciduous leaves. Species in Group 2 were reduced by fire and distinguished from Group 1 by longer lifespans and evergreen leaves. Group 3 species, which also decreased after fire, were characterized by long lifespans, large non-wind dispersed seeds, and taller heights. Our results show that PFTs based on life-history traits can reliably predict the responses of most species to fire in the Mojave Desert. Dominant, long-lived species of this region possess a combination of traits limiting their ability to recover, presenting a clear example of how a novel disturbance regime may shift selective environmental pressures to favor alternative life-history strategies. PMID:25247062

Life-history traits predict perennial species response to fire in a desert ecosystem

USGS Publications Warehouse

Shryock, Daniel F.; DeFalco, Lesley A.; Esque, Todd C.

2014-01-01

The Mojave Desert of North America has become fire-prone in recent decades due to invasive annual grasses that fuel wildfires following years of high rainfall. Perennial species are poorly adapted to fire in this system, and post-fire shifts in species composition have been substantial but variable across community types. To generalize across a range of conditions, we investigated whether simple life-history traits could predict how species responded to fire. Further, we classified species into plant functional types (PFTs) based on combinations of life-history traits and evaluated whether these groups exhibited a consistent fire-response. Six life-history traits varied significantly between burned and unburned areas in short (up to 4 years) or long-term (up to 52 years) post-fire datasets, including growth form, lifespan, seed size, seed dispersal, height, and leaf longevity. Forbs and grasses consistently increased in abundance after fire, while cacti were reduced and woody species exhibited a variable response. Woody species were classified into three PFTs based on combinations of life-history traits. Species in Group 1 increased in abundance after fire and were characterized by short lifespans, small, wind-dispersed seeds, low height, and deciduous leaves. Species in Group 2 were reduced by fire and distinguished from Group 1 by longer lifespans and evergreen leaves. Group 3 species, which also decreased after fire, were characterized by long lifespans, large non-wind dispersed seeds, and taller heights. Our results show that PFTs based on life-history traits can reliably predict the responses of most species to fire in the Mojave Desert. Dominant, long-lived species of this region possess a combination of traits limiting their ability to recover, presenting a clear example of how a novel disturbance regime may shift selective environmental pressures to favor alternative life-history strategies.

Application of Diversity Indices to Quantify Early Life-History Diversity for Chinook Salmon

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

Johnson, Gary E.; Sather, Nichole K.; Skalski, John R.

2014-03-01

We developed an index of early life history diversity (ELHD) for Pacific salmon (Oncorhynchus spp.) Early life history diversity is the variation in morphological and behavioral traits expressed within and among populations by individual juvenile salmon during their downstream migration. A standard quantitative method does not exist for this prominent concept in salmon biology.

Agency and Female Teachers' Career Decisions: A Life History Study of 40 Women

ERIC Educational Resources Information Center

Smith, Joan

2011-01-01

This article reports on some of the findings of a wider, life history study on the factors affecting the career decisions of 40 female secondary school teachers in England. By using life history interviews, it was possible to gain rich and nuanced insights into the complexity of factors influencing women's career decisions. While acknowledging the…

Life Course Stage in Young Adulthood and Intergenerational Congruence in Family Attitudes

ERIC Educational Resources Information Center

Bucx, Freek; Raaijmakers, Quinten; van Wel, Frits

2010-01-01

We investigated how intergenerational congruence in family-related attitudes depends on life course stage in young adulthood. Recent data from the Netherlands Kinship Panel Study were used; the present sample included 2,041 dyads of young adults and their parents. Findings are discussed in terms of the elasticity in intergenerational attitude…

Life-history variability of non-native centrarchids in regulated river systems of the lower River Guadiana drainage (south-west Iberian Peninsula).

PubMed

Ribeiro, F; Collares-Pereira, M J

2010-02-01

Life-history variability of two non-native centrarchids, pumpkinseed Lepomis gibbosus and largemouth bass Micropterus salmoides, was evaluated in three stream stretches of the lower River Guadiana drainage (south-west Iberian Peninsula) with different degrees of regulated flows. Abundance, condition and population structure differed among populations for both species, but invasion success was lower in the least regulated river. Lepomis gibbosus were abundant and had multiple age classes in the three river sites, whereas M. salmoides were less abundant and mainly represented by young-of-the-year fish. Juvenile growth in L. gibbosus was similar in all three populations, though longevity was slightly greater in the population from the River Guadiana mainstream. Lepomis gibbosus exhibited a long reproductive season, but the duration of season, size at maturity and reproductive effort varied among populations. The life-history differences found demonstrate the importance of species adaptation to local conditions which might favour their invasion success. Lepomis gibbosus were more adaptable and resilient to local conditions, whereas M. salmoides seemed dependent on reservoirs and large rivers for maintenance of riverine populations.

Influence of the indirect effects of guppies on life-history evolution in Rivulus hartii.

PubMed

Walsh, Matthew R; Reznick, David N

2010-06-01

Early theories of life-history evolution predict that increased predation on young/small individuals selects for delayed maturation and decreased reproductive effort, but such theory only considers changes in mortality. Predators reduce prey abundance and increase food to survivors. Theory that incorporates such indirect effects yields different predictions. Trinidadian killifish, Rivulus hartii, inhabit communities with and without guppies. Guppies prey on young Rivulus and Rivulus densities decline and growth rates increase when guppies are present. Prior work showed that Rivulus phenotypes from communities with guppies matured earlier and had higher fecundity, consistent with theories that incorporate indirect effects. Here we examined the genetic basis of these differences by rearing 2nd generation, laboratory-born Rivulus from sites with and without guppies under two food levels that match natural differences in growth. Many locality x food interactions were significant, often reversing the relationship between communities. Such interactions imply that there are fitness trade-offs associated with adaptation to high or low resource environments. On high food, Rivulus from localities with guppies matured earlier, produced many small eggs, and exhibited increased reproductive investment; these differences reversed on low food. Our results suggest that indirect effects mold Rivulus evolution and thereby highlight connections between community processes and evolutionary change.

Stressful life experiences in adolescence and cardiometabolic risk factors in young adulthood.

PubMed

Wickrama, Kandauda A S; Lee, Tae-Kyoung; O'Neal, Catherine Walker

2015-04-01

An increasing number of studies have provided evidence for the persistent influence of childhood/adolescent socioeconomic adversities on subsequent health outcomes. However, less is known about the distinct and additive influences of these early socioeconomic adversities and adolescents' own stressful life experiences on health outcomes in young adulthood. We used data from 11,030 adolescents who participated in the National Longitudinal Study of Adolescent Health at Waves 1, 3, and 4 and provided biomarker data at Wave 4. Three early socioeconomic adversities (community socioeconomic adversity, family economic hardship, and low parental education) were evaluated. Adolescents' stressful transition to young adulthood was captured by six specific precocious life events as follows: early sex, early marriage or cohabitation, early leaving home, early pregnancy, early employment, and truncated education. A summary measure of cardiovascular and metabolic disease risk was assessed using nine biomarkers. Univariate, bivariate, and multivariate regression analyses were employed. Early socioeconomic adversities and stressful life transition events were uniquely associated with elevated levels of cardiometabolic (CM) biomarkers and cumulative CM disease risk. For all of the biomarkers, young adults in high-adversity/stress groups were more likely to be in the high CM disease risk groups (>75th percentile) than in the low-adversity/stress groups. These findings provide support for the influence of multiple early socioeconomic adversities and adolescents' stressful life transitions on their CM disease risk as young adults. Increased efforts to prevent and mitigate these experiences may improve disease risks across a number of biomarkers. Copyright © 2015 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Associations among Aspects of Meaning in Life and Death Anxiety in Young Adults

ERIC Educational Resources Information Center

Lyke, Jennifer

2013-01-01

This investigation explored the relationship between two aspects of meaning in life, presence of meaning in life and search for meaning in life, and the fear of death and dying in young adults. A community sample of participants ("N" = 168) completed measures of meaning in life and death anxiety. A multivariate analysis of variance was…

Blood, sweat and plaster casts: Reviewing the history, composition, and scientific value of the Raymond A. Dart Collection of African Life and Death Masks.

PubMed

Houlton, T M R; Billings, B K

2017-10-01

This paper addresses the history, composition and scientific value of one of the most comprehensive facemask collections in Africa, the Raymond A. Dart Collection of African Life and Death Masks. Housed within the School of Anatomical Sciences at the University of the Witwatersrand (South Africa), it comprises 1110 masks (397 life, 487 death, 226 unknown). Life masks represent populations throughout Africa; death masks predominately southern Africa. Males preponderate by 75%. Recorded ages are error prone, but suggest most life masks are those of <35 year-olds, death masks of 36+ year-olds. A total of 241 masks have associated skeletons, 209 presenting a complete skull. Life masks date between 1927 and c.1980s, death masks 1933 and 1963. This historical collection presents uncanny associations with outmoded typological and evolutionary theories. Once perceived an essential scientific resource, performed craniofacial superimpositions identify the nose as the only stable feature maintained, with the remaining face best preserved in young individuals with minimal body fat. The facemask collection is most viable for teaching and research within the history of science, specifically physical anthropology, and presents some value to craniofacial identification. Future research will have to be conducted with appropriate ethical considerations to science and medicine. Copyright © 2017 Elsevier GmbH. All rights reserved.

Access to and use of sexual health care services among young Canadians with and without a history of sexual coercion

PubMed Central

O’Sullivan, Lucia F.; Sandra Byers, E.; Brotto, Lori A.; Majerovich, Jo Ann

2015-01-01

Objective To determine access to and use of sexual health care services among adolescents and young adults with and without a history of sexual coercion, and to examine whether a history of sexual coercion was a barrier to using sexual health care services. Design Online survey. Setting Canada. Participants A total of 405 adolescents and young adults aged 16 to 21. Main outcome measures Participants’ sexual histories, sexual coercion histories, current psychological functioning, and perceptions and use of health care services. Results A history of sexual coercion was reported by 29.6% of participants; more female participants reported a history of sexual coercion than male participants did, and female participants reported more related distress than male participants did. Those with a history of sexual coercion reported more sexual health–related visits than those without a history of sexual coercion did. Among participants with and without sexual coercion histories, there were no differences in difficulty accessing care, perceived quality of care, or rates of unmet health needs. Among those who reported a history of sexual coercion, the odds of having a sexual health–related visit increased for those who had had a routine checkup in the previous year (odds ratio = 8.29) and those who believed it was not difficult to access care (odds ratio = 1.74). Conclusion Having a history of sexual coercion was not a barrier to the use of health care services among adolescents and young adults. In fact, rates of health care service use were higher among those with a history of sexual coercion than those without such a history. PMID:26759846

Diagnosing the dangerous demography of manta rays using life history theory.

PubMed

Dulvy, Nicholas K; Pardo, Sebastián A; Simpfendorfer, Colin A; Carlson, John K

2014-01-01

Background. The directed harvest and global trade in the gill plates of mantas, and devil rays, has led to increased fishing pressure and steep population declines in some locations. The slow life history, particularly of the manta rays, is cited as a key reason why such species have little capacity to withstand directed fisheries. Here, we place their life history and demography within the context of other sharks and rays. Methods. Despite the limited availability of data, we use life history theory and comparative analysis to estimate the intrinsic risk of extinction (as indexed by the maximum intrinsic rate of population increase r max) for a typical generic manta ray using a variant of the classic Euler-Lotka demographic model. This model requires only three traits to calculate the maximum intrinsic population growth rate r max: von Bertalanffy growth rate, annual pup production and age at maturity. To account for the uncertainty in life history parameters, we created plausible parameter ranges and propagate these uncertainties through the model to calculate a distribution of the plausible range of r max values. Results. The maximum population growth rate r max of manta ray is most sensitive to the length of the reproductive cycle, and the median r max of 0.116 year(-1) 95th percentile [0.089-0.139] is one of the lowest known of the 106 sharks and rays for which we have comparable demographic information. Discussion. In common with other unprotected, unmanaged, high-value large-bodied sharks and rays the combination of very low population growth rates of manta rays, combined with the high value of their gill rakers and the international nature of trade, is highly likely to lead to rapid depletion and potential local extinction unless a rapid conservation management response occurs worldwide. Furthermore, we show that it is possible to derive important insights into the demography extinction risk of data-poor species using well-established life history theory.

Diagnosing the dangerous demography of manta rays using life history theory

PubMed Central

Pardo, Sebastián A.; Simpfendorfer, Colin A.; Carlson, John K.

2014-01-01

Background. The directed harvest and global trade in the gill plates of mantas, and devil rays, has led to increased fishing pressure and steep population declines in some locations. The slow life history, particularly of the manta rays, is cited as a key reason why such species have little capacity to withstand directed fisheries. Here, we place their life history and demography within the context of other sharks and rays. Methods. Despite the limited availability of data, we use life history theory and comparative analysis to estimate the intrinsic risk of extinction (as indexed by the maximum intrinsic rate of population increase rmax) for a typical generic manta ray using a variant of the classic Euler–Lotka demographic model. This model requires only three traits to calculate the maximum intrinsic population growth rate rmax: von Bertalanffy growth rate, annual pup production and age at maturity. To account for the uncertainty in life history parameters, we created plausible parameter ranges and propagate these uncertainties through the model to calculate a distribution of the plausible range of rmax values. Results. The maximum population growth rate rmax of manta ray is most sensitive to the length of the reproductive cycle, and the median rmax of 0.116 year−1 95th percentile [0.089–0.139] is one of the lowest known of the 106 sharks and rays for which we have comparable demographic information. Discussion. In common with other unprotected, unmanaged, high-value large-bodied sharks and rays the combination of very low population growth rates of manta rays, combined with the high value of their gill rakers and the international nature of trade, is highly likely to lead to rapid depletion and potential local extinction unless a rapid conservation management response occurs worldwide. Furthermore, we show that it is possible to derive important insights into the demography extinction risk of data-poor species using well-established life history theory

Life Histories of Three Exemplary American Physical Educators

ERIC Educational Resources Information Center

Cazers, Gunars

2009-01-01

The purpose of the following article-style dissertation was to present the life histories of three exemplary physical educators, to give them voice, explore ways in which they experienced marginalization, and describe how they persevered in spite of difficulties they experienced in their careers. The participants included (a) Robin, a female…

The Relationship between the Self-Efficacy and Life Satisfaction of Young Adults

ERIC Educational Resources Information Center

Çakar, Firdevs Savi

2012-01-01

The aim of this study is to examine the relationship between self-efficacy and life satisfaction of young adults. This study is cross-sectional study and variables. Data were collected between March 2012 and April 2012 from young adults who were bachelor degree and attending the Celal Bayar University Pedagogical Formation Program the academic…

Intersections of life histories and science identities: the stories of three preservice elementary teachers

NASA Astrophysics Data System (ADS)

Avraamidou, Lucy

2016-03-01

Grounded within Connelly and Clandinin's conceptualization of teachers' professional identity in terms of 'stories to live by' and through a life-history lens, this multiple case study aimed to respond to the following questions: (a) How do three preservice elementary teachers view themselves as future science teachers? (b) How have the participants' life histories shaped their science identity trajectories? In order to characterize the participants' formation of science identities over time, various data regarding their life histories in relation to science were collected: science biographies, self-portraits, interviews, reflective journals, lesson plans, and classroom observations. The analysis of the data illustrated how the three participants' identities have been in formation from the early years of their lives and how various events, experiences, and interactions had shaped their identities through time and across contexts. These findings are discussed alongside implications for theory, specifically, identity and life-history intersections, for teacher preparation, and for research related to explorations of beginning elementary teachers' identity trajectories.

Putting all your eggs in one basket: life-history strategies, bet hedging, and diversification.

PubMed

White, Andrew Edward; Li, Yexin Jessica; Griskevicius, Vladas; Neuberg, Steven L; Kenrick, Douglas T

2013-05-01

Diversification of resources is a strategy found everywhere from the level of microorganisms to that of giant Wall Street investment firms. We examine the functional nature of diversification using life-history theory-a framework for understanding how organisms navigate resource-allocation trade-offs. This framework suggests that diversification may be adaptive or maladaptive depending on one's life-history strategy and that these differences should be observed under conditions of threat. In three studies, we found that cues of mortality threat interact with one index of life-history strategy, childhood socioeconomic status (SES), to affect diversification. Among those from low-SES backgrounds, mortality threat increased preferences for diversification. However, among those from high-SES backgrounds, mortality threat had the opposite effect, inclining people to put all their eggs in one basket. The same interaction pattern emerged with a potential biomarker of life-history strategy, oxidative stress. These findings highlight when, and for whom, different diversification strategies can be advantageous.

Family History of Sudden Cardiac Death of the Young: Prevalence and Associated Factors

PubMed Central

White, Michelle J.; Duquette, Debra; Bach, Janice; Rafferty, Ann P.; Fussman, Chris; Sharangpani, Ruta; Russell, Mark W.

2015-01-01

Sudden cardiac death of the young (SCDY) is a devastating event for families and communities. Family history is a significant risk factor for this potentially preventable cause of death, however a complete and detailed family history is not commonly obtained during routine health maintenance visits. To estimate the proportion of adults with a family history of SCDY, the Michigan Department of Health and Human Services (MDHHS) Genomics Program included two questions within the 2007 Michigan Behavioral Risk Factor Survey (MiBRFS). Prevalence estimates and 95% confidence intervals were calculated. Among adults in Michigan, 6.3% reported a family history of SCDY, with a greater prevalence among blacks, those with lower household income, and those with less education. Among those reporting a family history of SCDY, 42.3% had at least one first-degree relative and 26.2% had multiple affected family members. This is the first study to demonstrate the prevalence of family history of SCDY while also highlighting key sociodemographic characteristics associated with increased prevalence. These findings should guide evidence-based interventions to reach those at greatest risk. PMID:27417815

The Adolescent and Young Adult with Cancer: A Developmental Life Course Perspective.

PubMed

Docherty, Sharron L; Kayle, Mariam; Maslow, Gary R; Santacroce, Sheila Judge

2015-08-01

Using a Life Course Health Development framework, this article summarizes what is known about the impact of cancer and its treatment on the biopsychosocial world of the adolescent and young adult. Published peer reviewed literature, web-based resources, and cancer-related professional organizations' resources. Adolescents and young adults with cancer, between 15 and 29 years of age, have emerged as a distinct group requiring specialized care. The demands of cancer and its treatment are often directly counter to the developmental needs of this age group and often alter those life course experiences that contribute to resilience, thriving, and flourishing. Providing high-quality care to this age group requires a depth of understanding of the complexity of factors that merge to influence the developmental life course. Copyright © 2015 Elsevier Inc. All rights reserved.

Convergent and correlated evolution of major life-history traits in the angiosperm genus Leucadendron (Proteaceae).

PubMed

Tonnabel, Jeanne; Mignot, Agnès; Douzery, Emmanuel J P; Rebelo, Anthony G; Schurr, Frank M; Midgley, Jeremy; Illing, Nicola; Justy, Fabienne; Orcel, Denis; Olivieri, Isabelle

2014-10-01

Natural selection is expected to cause convergence of life histories among taxa as well as correlated evolution of different life-history traits. Here, we quantify the extent of convergence of five key life-history traits (adult fire survival, seed storage, degree of sexual dimorphism, pollination mode, and seed-dispersal mode) and test hypotheses about their correlated evolution in the genus Leucadendron (Proteaceae) from the fire-prone South African fynbos. We reconstructed a new molecular phylogeny of this highly diverse genus that involves more taxa and molecular markers than previously. This reconstruction identifies new clades that were not detected by previous molecular study and morphological classifications. Using this new phylogeny and robust methods that account for phylogenetic uncertainty, we show that the five life-history traits studied were labile during the evolutionary history of the genus. This diversity allowed us to tackle major questions about the correlated evolution of life-history strategies. We found that species with longer seed-dispersal distances tended to evolve lower pollen-dispersal distance, that insect-pollinated species evolved decreased sexual dimorphism, and that species with a persistent soil seed-bank evolved toward reduced fire-survival ability of adults. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

Fine scale relationships between sex, life history, and dispersal of masu salmon

USGS Publications Warehouse

Kitanishi, Shigeru; Yamamoto, Toshiaki; Koizumi, Itsuro; Dunham, Jason B.; Higashi, Seigo

2012-01-01

Identifying the patterns and processes driving dispersal is critical for understanding population structure and dynamics. In many organisms, sex-biased dispersal is related to the type of mating system. Considerably less is known about the influence of life history variability on dispersal. Here we investigated patterns of dispersal in masu salmon (Oncorhynchus masou) to evaluate influences of sex and life history on dispersal. As expected, assignment tests and isolation by distance analysis revealed that dispersal of marine-migratory masu salmon was male-biased. However, dispersal of resident and migratory males did not follow our expectation and marine-migratory individuals dispersed more than residents. This may be because direct competition between marine-migratory and resident males is weak or that the cost of dispersal is smaller for marine-migratory individuals. This study revealed that both sex and migratory life history influence patterns of dispersal at a local scale in masu salmon.

The conservation and management of tunas and their relatives: setting life history research priorities.

PubMed

Juan-Jordá, Maria José; Mosqueira, Iago; Freire, Juan; Dulvy, Nicholas K

2013-01-01

Scombrids (tunas, bonitos, Spanish mackerels and mackerels) support important fisheries in tropical, subtropical and temperate waters around the world, being one of the most economically- and socially-important marine species globally. Their sustainable exploitation, management and conservation depend on accurate life history information for the development of quantitative fisheries stock assessments, and in the fishery data-poor situations for the identification of vulnerable species. Here, we assemble life history traits (maximum size, growth, longevity, maturity, fecundity, spawning duration and spawning interval) for the 51 species of scombrids globally. We identify major biological gaps in knowledge and prioritize life history research needs in scombrids based on their biological gaps in knowledge, the importance of their fisheries and their current conservation status according to the International Union for Conservation of Nature Red List. We find that the growth and reproductive biology of tunas and mackerel species have been more extensively studied than for Spanish mackerels and bonitos, although there are notable exceptions in all groups. We also reveal that reproductive biology of species, particular fecundity, is the least studied biological aspect in scombrids. We identify two priority groups, including 32 species of scombrids, and several populations of principal market tunas, for which life history research should be prioritized following the species-specific life history gaps identified in this study in the coming decades. By highlighting the important gaps in biological knowledge and providing a priority setting for life history research in scombrid species this study provides guidance for management and conservation and serves as a guide for biologists and resource managers interested in the biology, ecology, and management of scombrid species.

The Conservation and Management of Tunas and Their Relatives: Setting Life History Research Priorities

PubMed Central

Juan-Jordá, Maria José; Mosqueira, Iago; Freire, Juan; Dulvy, Nicholas K.

2013-01-01

Scombrids (tunas, bonitos, Spanish mackerels and mackerels) support important fisheries in tropical, subtropical and temperate waters around the world, being one of the most economically- and socially-important marine species globally. Their sustainable exploitation, management and conservation depend on accurate life history information for the development of quantitative fisheries stock assessments, and in the fishery data-poor situations for the identification of vulnerable species. Here, we assemble life history traits (maximum size, growth, longevity, maturity, fecundity, spawning duration and spawning interval) for the 51 species of scombrids globally. We identify major biological gaps in knowledge and prioritize life history research needs in scombrids based on their biological gaps in knowledge, the importance of their fisheries and their current conservation status according to the International Union for Conservation of Nature Red List. We find that the growth and reproductive biology of tunas and mackerel species have been more extensively studied than for Spanish mackerels and bonitos, although there are notable exceptions in all groups. We also reveal that reproductive biology of species, particular fecundity, is the least studied biological aspect in scombrids. We identify two priority groups, including 32 species of scombrids, and several populations of principal market tunas, for which life history research should be prioritized following the species-specific life history gaps identified in this study in the coming decades. By highlighting the important gaps in biological knowledge and providing a priority setting for life history research in scombrid species this study provides guidance for management and conservation and serves as a guide for biologists and resource managers interested in the biology, ecology, and management of scombrid species. PMID:23950930

Evolution of dispersal and life history strategies – Tetrahymena ciliates

PubMed Central

Fjerdingstad, Else J; Schtickzelle, Nicolas; Manhes, Pauline; Gutierrez, Arnaud; Clobert, Jean

2007-01-01

Background Considerable attention has focused on how selection on dispersal and other core life-history strategies (reproductive effort, survival ability, colonization capacity) may lead to so-called dispersal syndromes. Studies on genetic variation in these syndromes within species could importantly increase our understanding of their evolution, by revealing whether traits co-vary across genetic lineages in the manner predicted by theoretical models, and by stimulating further hypotheses for experimental testing. Yet such studies remain scarce. Here we studied the ciliated protist Tetrahymena thermophila, a particularly interesting organism due to cells being able to transform into morphs differing dramatically in swim-speed. We investigated dispersal, morphological responses, reproductive performance, and survival in ten different clonal strains. Then, we examined whether life history traits co-varied in the manner classically predicted for ruderal species, examined the investment of different strains into short- and putative long-distance dispersal, while considering also the likely impact of semi-sociality (cell aggregation, secretion of 'growth factors') on dispersal strategies. Results Very significant among-strain differences were found with regard to dispersal rate, morphological commitment and plasticity, and almost all core life-history traits (e.g. survival, growth performance and strategy), with most of these traits being significantly intercorrelated. Some strains showed high short-distance dispersal rates, high colonization capacity, bigger cell size, elevated growth performance, and good survival abilities. These well performing strains, however, produced fewer fast-swimming dispersal morphs when subjected to environmental degradation than did philopatric strains performing poorly under normal conditions. Conclusion Strong evidence was found for a genetic covariation between dispersal strategies and core life history traits in T. thermophila, with a

Bringing Ancient History Back To Life: An Interview With Nancy Toff

ERIC Educational Resources Information Center

Curriculum Review, 2005

2005-01-01

Nancy Toff, editorial director of school and young adult publishing at Oxford University Press, is out to revolutionize the teaching of history in middle schools. In this interview, she discusses how two new Oxford series, the nine-book, The World in Ancient Times and the seven-book, The Medieval & Early Modern World, get away from the notion of…

Health-related quality of life of young women with breast cancer. Review of the literature.

PubMed

Yfantis, Aris; Intas, George; Tolia, Maria; Nikolaou, Michail; Tsoukalas, Nikolaos; Lymperi, Maria; Kyrgias, George; Zografos, George; Kontos, Michalis

2018-01-01

The purpose of the present article was to investigate the health related quality of life (QoL) of young women with breast cancer. For the purposes of this article, we reviewed the literature via the electronic databases Pubmed, Scopus and Google Scholar. Key words used were breast cancer, young women, health related quality of life, and quality of life. Young women reported fatigue, pain in the breast and hand problems with lymphedema as the most frequent physical effects of treatment. Other physical problems were the not periodic and painful menses, vaginal dryness and loss of libido. Many young women had depressive symptoms such as depressed mood, helplessness, hopelessness, sleep loss, psychomotor retardation and disorders of appetite. There were often concerns about the health monitoring and self-image, while they were anxious if they will have a baby in the future or if they can nurture the existing ones. Many problems arose in the career of young women. They faced discrimination in the labor supply and/or layoff because they were considered unable to do their job effectively. In addition, they reported isolation problems and feeling different from other women of similar age. Young women consider that their healthrelated QoL is worse compared with older women. Young women worry about their future, with particular reference to their role as mothers and especially to children-bearing. The free screening and non-exclusion of young women is particularly important for breast cancer prevention and women's well-being.

Effects and Effectiveness of Life Skills Education for HIV Prevention in Young People

ERIC Educational Resources Information Center

Yankah, Ekua; Aggleton, Peter

2008-01-01

For 20 years, "life skills" education has been advocated as a key component of HIV and AIDS education for young people. But what do terms such as life skills imply, and what evidence is there that a life skills-based approach really works? This article reviews the literature on the effects and effectiveness of life skills-based education for HIV…

Potential effects of changes in temperature and food resources on life history trajectories of juvenile Oncorhynchus mykiss

USGS Publications Warehouse

Benjamin, Joseph R.; Connolly, Patrick J.; Romine, Jason G.; Perry, Russell W.

2013-01-01

Increasing temperatures and changes in food resources owing to climate change may alter the growth and migratory behavior of organisms. This is particularly important for salmonid species like Oncorhynchus mykiss, where some individuals remain in freshwater to mature (nonanadromous Rainbow Trout) and others migrate to sea (anadromous Steelhead). Whether one strategy is adopted over the other may depend on the individual's growth and size. In this study, we explored (1) how water temperature in Beaver Creek, a tributary to the Methow River, Washington, may increase under four climate scenarios, (2) how these thermal changes may alter the life history trajectory followed by O. mykiss (i.e., when and if to smolt), and (3) how changes in food quality or quantity might interact with increasing temperatures. We combined bioenergetic and state-dependent life history models parameterized for O. mykiss in Beaver Creek to mimic baseline life history trajectories. Based on our simulations, when mean water temperature was increased by 0.6°C there was a reduction in life history diversity and a 57% increase in the number of individuals becoming smolts. When mean temperature was increased by 2.7°C, it resulted in 87% fewer smolts than in the baseline and fewer life history trajectories expressed. A reduction in food resources led to slower growth, more life history trajectories, and a greater proportion of smolts. In contrast, when food resources were increased, fish grew faster, which reduced the proportion of smolts and life history diversity. Our modeling suggests that warmer water temperatures associated with climate change could decrease the life history diversity of O. mykiss in the central portion of their range and thereby reduce resiliency to other disturbances. In addition, changes in food resources could mediate or exacerbate the effect of water temperature on the life history trajectories of O. mykiss.

Entry of Young People into Working Life. General Report.

ERIC Educational Resources Information Center

Organisation for Economic Cooperation and Development, Paris (France).

This booklet examines the problems encountered by youth while making the school-to-work transition and analyzes the measures undertaken in the Organization for Economic Co-operation and Development (OECD) member countries to deal with youth unemployment. Part I in an analysis of young people's difficulties in entering the working life describes…

Growth and life history variability of the grey reef shark (Carcharhinus amblyrhynchos) across its range.

PubMed

Bradley, Darcy; Conklin, Eric; Papastamatiou, Yannis P; McCauley, Douglas J; Pollock, Kydd; Kendall, Bruce E; Gaines, Steven D; Caselle, Jennifer E

2017-01-01

For broadly distributed, often overexploited species such as elasmobranchs (sharks and rays), conservation management would benefit from understanding how life history traits change in response to local environmental and ecological factors. However, fishing obfuscates this objective by causing complex and often mixed effects on the life histories of target species. Disentangling the many drivers of life history variability requires knowledge of elasmobranch populations in the absence of fishing, which is rarely available. Here, we describe the growth, maximum size, sex ratios, size at maturity, and offer a direct estimate of survival of an unfished population of grey reef sharks (Carcharhinus amblyrhynchos) using data from an eight year tag-recapture study. We then synthesized published information on the life history of C. amblyrhynchos from across its geographic range, and for the first time, we attempted to disentangle the contribution of fishing from geographic variation in an elasmobranch species. For Palmyra's unfished C. amblyrhynchos population, the von Bertalanffy growth function (VBGF) growth coefficient k was 0.05 and asymptotic length L∞ was 163.3 cm total length (TL). Maximum size was 175.5 cm TL from a female shark, length at maturity was estimated at 116.7-123.2 cm TL for male sharks, maximum lifespan estimated from VBGF parameters was 18.1 years for both sexes combined, and annual survival was 0.74 year-1. Consistent with findings from studies on other elasmobranch species, we found significant intraspecific variability in reported life history traits of C. amblyrhynchos. However, contrary to what others have reported, we did not find consistent patterns in life history variability as a function of biogeography or fishing. Ultimately, the substantial, but not yet predictable variability in life history traits observed for C. amblyrhynchos across its geographic range suggests that regional management may be necessary to set sustainable harvest

Old world versus new world: life-history alterations in a successful invader introduced across Europe.

PubMed

Fox, Michael G; Copp, Gordon H

2014-02-01

We examined differences in pumpkinseed (Lepomis gibbosus) life-history traits between native North American and introduced European populations, and tested three life-history predictions related to the effect of temperature, growth, waterbody size, and the presence/absence of predators on native and non-native populations. Pumpkinseed populations exhibit more 'opportunistic' traits (earlier maturity, smaller size at maturity, and higher reproductive allocation) in their introduced European range than those in their native range. Predictions of life-history traits were improved when indicators of juvenile growth rate (mean length at age 2), waterbody size (surface area), and thermal regime (air temperature degree-days above 10 °C) were incorporated into models along with continental location, but European pumpkinseed populations exhibit more opportunistic life-history traits than North American populations even when these factors are accounted for. Native pumpkinseed in waterbodies containing piscivores mature later and at a larger size, and have lower gonadosomatic indices than those in waterbodies lacking piscivores, whereas there is no significant difference in the same three life-history traits between European waterbodies containing or lacking piscivores. Because congeneric competitors of the pumpkinseed are absent from Europe, the apparent absence of a predator life-history effect there could also be due to the absence of the major sunfish competitors. In either case, the evolution and maintenance of more opportunistic traits in European pumpkinseed can likely be attributed to enemy release, and this may explain the successful establishment and spread of pumpkinseed in many parts of Europe.

Variation in reproductive life history traits between two populations of Blackbanded Darters (Percina nigrofasciata)

USGS Publications Warehouse

Hughey, Myra C.; Heins, David C.; Jelks, Howard L.; Ory, Bridget A.; Jordan, Frank

2012-01-01

We examined the life history of Blackbanded Darters (Percina nigrofasciata) from two streams in the Choctawhatchee River drainage, Florida, over a three-year study period. Blackbanded Darters from Turkey Creek were longer than fish from Ten Mile Creek; however, size-adjusted clutch and egg sizes were similar between populations. Larger females produced larger clutches, whereas egg size did not vary with female body size. Seasonally, clutch sizes were greater in May than in August. When contrasted with previous studies of Blackbanded Darters in Alabama and Louisiana, the reproductive season of Blackbanded Darters in Florida was unusually long, ceasing for only a few months in late fall. The reproductive season was longer in Turkey Creek than in Ten Mile Creek. Differences in thermal regime among streams may explain differences in life history traits among local and distant populations of Blackbanded Darters. This research, alone and in combination with previous studies of this species, emphasizes two main points. First, it reaffirms that life history studies based on a single locality or conducted at a single point in time may fail to capture the full range of variation in life history traits. Second, it highlights the extensive phenotypic variation found in species with broad geographic ranges. Such species lend themselves to comparative and experimental research on patterns and causes of life history variation.

Horizontal Gene Transfer and the History of Life

PubMed Central

Daubin, Vincent; Szöllősi, Gergely J.

2016-01-01

Microbes acquire DNA from a variety of sources. The last decades, which have seen the development of genome sequencing, have revealed that horizontal gene transfer has been a major evolutionary force that has constantly reshaped genomes throughout evolution. However, because the history of life must ultimately be deduced from gene phylogenies, the lack of methods to account for horizontal gene transfer has thrown into confusion the very concept of the tree of life. As a result, many questions remain open, but emerging methodological developments promise to use information conveyed by horizontal gene transfer that remains unexploited today. PMID:26801681

Rapid onset pressor response to exercise in young women with a family history of hypertension.

PubMed

Matthews, Evan L; Greaney, Jody L; Wenner, Megan M

2017-09-01

What is the central question of this study? Alterations in blood pressure control at exercise onset are apparent in older adults with established cardiovascular disease. It is currently not known whether these alterations are evident in young adults with a family history of hypertension. What is the main finding and its importance? We demonstrate that young women with a family history of hypertension display a larger change in blood pressure within the first 10 s of isometric exercise. These data suggest altered blood pressure control in young women with a family history of hypertension. Hypertensive adults demonstrate atypical increases in blood pressure (BP) and muscle sympathetic nerve activity (MSNA) at the immediate onset of static muscle contraction. However, it is unknown whether these abnormal responses occur in young, otherwise healthy adults at risk for developing future disease, such as those with a family history of hypertension (+FH). We tested the hypothesis that +FH young women have exaggerated increases in BP and MSNA at the onset of static muscle contraction compared with those without a family history of hypertension (-FH). We retrospectively examined beat-by-beat BP and MSNA during the initial 30 s of isometric handgrip exercise (30% of maximal voluntary contraction) in 16 +FH (22 ± 2 years old, 22 ± 3 kg m -2 ) and 16 -FH (22 ± 3 years old, 22 ± 3 kg m -2 ) women. Resting mean arterial pressure (+FH 80 ± 11 mmHg versus -FH 84 ± 13 mmHg), MSNA burst frequency (+FH 7 ± 3 bursts min -1 versus -FH 9 ± 5 bursts min -1 ) and burst incidence [+FH 12 ± 4 bursts (100 heart beats) -1 versus -FH 12 ± 8 bursts (100 heart beats) -1 ] were similar between groups (all P > 0.05). Within the first 10 s of exercise, changes in mean arterial pressure (+FH Δ8 ± 6 mmHg versus -FH Δ3 ± 2 mmHg, P < 0.05) and heart rate (+FH Δ8 ± 5 beats min -1 versus -FH Δ4 ± 4 beats min -1 , P < 0.05) were

Molecular Phylogenetics of the Genus Neoconocephalus (Orthoptera, Tettigoniidae) and the Evolution of Temperate Life Histories

PubMed Central

Snyder, Robert L.; Frederick-Hudson, Katy H.; Schul, Johannes

2009-01-01

Background The katydid genus Neoconocephalus (25+ species) has a prominent acoustic communication system and occurs in large parts of the Neotropics and Nearctic. This group has been subject of numerous behavioral, physiological, and evolutionary studies of its acoustic communication system. Two distinct life histories occur in this group: The tropical life history incorporates multiple generations/year and direct egg development without environmental triggers. Temperate life history is characterized by overwintering in the egg stage, cold trigger of egg development, and one generation/year. This study reconstructs the phylogenetic relationships within the genus to (1) determine the evolutionary history of the temperate life history, and (2) to support comparative studies of evolutionary and physiological problems in this genus. Methodology/Principal Findings We used Amplified Fragment Length Polymorphisms (AFLP), and sequences of two nuclear loci and one mitochondrial locus to reconstruct phylogenetic relationships. The analysis included 17 ingroup and two outgroup species. AFLP and mitochondrial data provided resolution at the species level while the two nuclear loci revealed only deeper nodes. The data sets were combined in a super-matrix to estimate a total evidence tree. Seven of the temperate species form a monophyletic group; however, three more temperate species were placed as siblings of tropical species. Conclusions/Significance Our analyses support the reliability of the current taxonomic treatment of the Neoconocephalus fauna of Caribbean, Central, and North America. Ancestral state reconstruction of life history traits was not conclusive, however at least four transitions between life histories occurred among our sample of species. The proposed phylogeny will strengthen conclusions from comparative work in this group. PMID:19779617

Survival on the ark: life history trends in captive parrots

PubMed Central

Young, Anna M.; Hobson, Elizabeth A.; Lackey, Laurie Bingaman; Wright, Timothy F.

2011-01-01

Members of the order Psittaciformes (parrots and cockatoos) are among the most long-lived and endangered avian species. Comprehensive data on lifespan and breeding are critical to setting conservation priorities, parameterizing population viability models, and managing captive and wild populations. To meet these needs, we analyzed 83, 212 life history records of captive birds from the International Species Information System and calculated lifespan and breeding parameters for 260 species of parrots (71% of extant species). Species varied widely in lifespan, with larger species generally living longer than smaller ones. The highest maximum lifespan recorded was 92 years in Cacatua moluccensis, but only 11 other species had a maximum lifespan over 50 years. Our data indicate that while some captive individuals are capable of reaching extraordinary ages, median lifespans are generally shorter than widely assumed, albeit with some increase seen in birds presently held in zoos. Species that lived longer and bred later in life tended to be more threatened according to IUCN classifications. We documented several individuals of multiple species that were able to breed for more than two decades, but the majority of clades examined had much shorter active reproduction periods. Post-breeding periods were surprisingly long and in many cases surpassed the duration of active breeding. Our results demonstrate the value of the ISIS database to estimate life history data for an at-risk taxon that is difficult to study in the wild, and provide life history data that is crucial for predictive modeling of future species endangerment and proactively managing captive populations of parrots. PMID:22389582

Prey life-history and bioenergetic responses across a predation gradient.

PubMed

Rennie, M D; Purchase, C F; Shuter, B J; Collins, N C; Abrams, P A; Morgan, G E

2010-10-01

To evaluate the importance of non-consumptive effects of predators on prey life histories under natural conditions, an index of predator abundance was developed for naturally occurring populations of a common prey fish, the yellow perch Perca flavescens, and compared to life-history variables and rates of prey energy acquisition and allocation as estimated from mass balance models. The predation index was positively related to maximum size and size at maturity in both male and female P. flavescens, but not with life span or reproductive investment. The predation index was positively related to size-adjusted specific growth rates and growth efficiencies but negatively related to model estimates of size-adjusted specific consumption and activity rates in both vulnerable (small) and invulnerable (large) size classes of P. flavescens. These observations suggest a trade-off between growth and activity rates, mediated by reduced activity in response to increasing predator densities. Lower growth rates and growth efficiencies in populations with fewer predators, despite increased consumption suggests either 1) a reduction in prey resources at lower predator densities or 2) an intrinsic cost of rapid prey growth that makes it unfavourable unless offset by a perceived threat of predation. This study provides evidence of trade-offs between growth and activity rates induced by predation risk in natural prey fish populations and illustrates how behavioural modification induced through predation can shape the life histories of prey fish species. © 2010 The Authors. Journal compilation © 2010 The Fisheries Society of the British Isles.

Life science research in space - risks and chances for young scientists

NASA Astrophysics Data System (ADS)

Horn, Eberhard R.

2007-09-01

Research in Space is well established in most fields of Life Science, and the number of scientific publications in highly ranked journals increases steadily. However, this kind of research, in particular, fundamental research is coming more and more under pressure, funding decreases, and the discussion about its benefit for men increases continuously. The question is whether these conditions are favorable to the young generation of scientists who are not only interested in this field of research but who is urgently needed for a successful continuation of Life Science research in Space. There are pros and cons that are related to science specific factors as well as to factors specific for space research and space technologies. A young scientist also faces obstacles such as the ever- coming questions about the benefit/cost relation and the sustainability of fundamental research in Space. Continuation of a successful Life Science research in Space with a high level of competitive power should be based on three columns, (1) high- ranked state- of- art experiments, (2) motivated young scientists, and (3) scientific security after completion of projects to avoid loss of knowledge. This aim has to be supported by politicians who express clearly (political) support of Space exploration programs, by universities and private research institutions including industry. Establishment of a European FALL- BACK PLAN (FBP) for situations when flight opportunities are lacking is a way to support young Space scientists in their efforts to regain competitiveness with respect to normal scientists on the basis of first rate peer reviewed research projects that will stand on its own, i.e., transiently with no competition with ground- researchers.

Short break and emergency respite care: what options for young people with life-limiting conditions?

PubMed

Mitchell, Tracy K; Knighting, Katherine; O'Brien, Mary R; Jack, Barbara A

2016-02-01

Service providers face difficult decisions about how best to develop services for the increasing numbers of young people with life-limiting conditions who require palliative care. To explore alternative short break and emergency respite care options to children's hospice care. A two-phase evaluation with young people, families and professionals. Phase 1: qualitative semi-structured interviews and focus groups (n=53). Phase 2: mixed-method survey (n=82), qualitative findings only. There were few, or no, appropriate short break and emergency respite care alternatives when children's hospice care was not available that can meet the need of young people with life-limiting conditions, creating anxiety for children's hospice users and those leaving the service as a result of reaching transition age or through no longer meeting the children's hospice eligibility criteria. Access to appropriate short break and emergency respite care is required to prevent lifelong negative consequences for young people with life-limiting conditions, their family and society. Research is undoubtedly required to explore the impact and outcomes of children's hospice discharge for young people and their family. Particular attention should be paid to the lack of services for an increasing population making the transition from children's hospices.

Cost-effectiveness of preparticipation screening for prevention of sudden cardiac death in young athletes.

PubMed

Wheeler, Matthew T; Heidenreich, Paul A; Froelicher, Victor F; Hlatky, Mark A; Ashley, Euan A

2010-03-02

Inclusion of 12-lead electrocardiography (ECG) in preparticipation screening of young athletes is controversial because of concerns about cost-effectiveness. To evaluate the cost-effectiveness of ECG plus cardiovascular-focused history and physical examination compared with cardiovascular-focused history and physical examination alone for preparticipation screening. Decision-analysis, cost-effectiveness model. Published epidemiologic and preparticipation screening data, vital statistics, and other publicly available data. Competitive athletes in high school and college aged 14 to 22 years. Lifetime. Societal. Nonparticipation in competitive athletic activity and disease-specific treatment for identified athletes with heart disease. Incremental health care cost per life-year gained. Addition of ECG to preparticipation screening saves 2.06 life-years per 1000 athletes at an incremental total cost of $89 per athlete and yields a cost-effectiveness ratio of $42 900 per life-year saved (95% CI, $21 200 to $71 300 per life-year saved) compared with cardiovascular-focused history and physical examination alone. Compared with no screening, ECG plus cardiovascular-focused history and physical examination saves 2.6 life-years per 1000 athletes screened and costs $199 per athlete, yielding a cost-effectiveness ratio of $76 100 per life-year saved ($62 400 to $130 000). Results are sensitive to the relative risk reduction associated with nonparticipation and the cost of initial screening. Effectiveness data are derived from 1 major European study. Patterns of causes of sudden death may vary among countries. Screening young athletes with 12-lead ECG plus cardiovascular-focused history and physical examination may be cost-effective. Stanford Cardiovascular Institute and the Breetwor Foundation.

Civil Rights Continued: How History Positions Young People to Contemplate Sexuality (In)justice

ERIC Educational Resources Information Center

Schmidt, Sandra J.

2014-01-01

Same-sex marriage is part of a global civil rights struggle for LGBQ rights. How this movement is framed, advanced, and critiqued across the globe can be linked to how young people in schools are prepared to deliberate social issues in the political sphere. This article examines national history books as cultural artifacts that present what is…

Rarity as a life-history correlate in Dudleya (Crassulaceae).

PubMed

Dorsey, Ann E; Wilson, Paul

2011-07-01

Differences in rarity among species can be caused by adaptation to local conditions along with correlated evolution in characters that limit geographic range size. For this kind of divergence, the resulting species differ in their ability to thrive in varying environments. Because rare species are more prone to extinction than widespread species, trade-offs in life history predispose the resulting lineages to clade selection. Nine Dudleya species live in the Santa Monica Mountains: five neoendemics, one species intermediate in rarity, and three with broader ranges. Life-history traits were correlated against one another. To understand habitat dependence, the species were grown in an inland garden and in a coastal garden, and the disparity in growth and reproduction in the two gardens was compared among species. Rare species reproduced earlier and grew to be smaller than common species. The small body size of the rare species was correlated with small reproductive outputs compared with those of the large-bodied common species. The growth disparity between plants in the two gardens was greatest for the rare species. The rare species had a lower tolerance for hot, dry conditions compared with the common species. In the Santa Monica Mountains, the habitat conditions required by the rare species are not as prevalent as those of the common species. The data are consistent with the view that differences in life histories constrained by trade-offs affect range size. Such differences in rarity become the grist for clade selection at the scale of macroevolution.

Quality of life of young patients with recurrent respiratory papillomatosis.

PubMed

Montaño-Velázquez, B B; Nolasco-Renero, J; Parada-Bañuelos, J E; Garcia-Vázquez, F; Flores-Medina, S; García-Romero, C S; Jáuregui-Renaud, K

2017-05-01

To assess quality of life of children and teenagers with recurrent respiratory papillomatosis, according to the evidence of infection by human papillomavirus types 6 and 11, compared with healthy volunteers and patients with chronic otitis media. Participants and their parents completed the Pediatric Quality of Life Inventory 4.0. Patients with recurrent respiratory papillomatosis and their parents reported lower quality of life than healthy subjects (p < 0.01), but similar quality of life to patients with chronic otitis media. Those with human papillomavirus type 11 showed the lowest scores among all participants (p < 0.05). Young Mexican patients with recurrent respiratory papillomatosis and their parents perceive a poor quality of life, and they may experience limitations in interactions with their peers. Infection by human papillomavirus type 11 may increase the impact of the disease on quality of life.

Life History Traits of an Extended Longevity Phenotype of Drosophila melanogaster.

PubMed

Deepashree, S; Shivanandappa, T; Ramesh, S R

2017-01-01

Aging or senescence is a complex biological phenomenon. Artificially selected Drosophila for extended longevity is one of the experimental models used to understand the mechanisms involved in aging and to test various theories. To examine the life history traits and biochemical defenses in relation to aging in an extended longevity phenotype of Drosophila melanogaster. Life history traits viz., survivability, fecundity, development time, dry weight, wing size, lipid content, starvation, desiccation and cold resistances, locomotory ability, antioxidant enzyme activities and reactive oxygen species level between control and selected lines of D. melanogaster were investigated. In our model of Drosophila, extended longevity is associated with no trade-off in fecundity and shows variable resistance to environmental stress such as starvation, cold and desiccation. Enhanced biochemical defense involving the antioxidant enzymes was positively correlated with longevity. Extended longevity phenotypes of Drosophila represent genomic plasticity associated with variable life history traits attributed to the genetic background of the progenitor population and the environment of selection. Oxidative stress resistance seems to be a significant factor in longevity. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Everyday Life of Young Adults with Intellectual Disabilities: Inclusionary and Exclusionary Processes among Young Adults of Parents with Intellectual Disability

ERIC Educational Resources Information Center

Starke, Mikaela

2013-01-01

Ten young adults with an intellectual disability whose parents, too, have an intellectual disability were interviewed and completed questionnaires for this exploratory study aimed at charting their experiences of everyday life. Most of the participants reported high life satisfaction, especially with the domains of friends, leisure time, and…

Life history factors, personality and the social clustering of sexual experience in adolescents.

PubMed

van Leeuwen, Abram J; Mace, Ruth

2016-10-01

Adolescent sexual behaviour may show clustering in neighbourhoods, schools and friendship networks. This study aims to assess how experience with sexual intercourse clusters across the social world of adolescents and whether predictors implicated by life history theory or personality traits can account for its between-individual variation and social patterning. Using data on 2877 adolescents from the Avon Longitudinal Study of Parents and Children, we ran logistic multiple classification models to assess the clustering of sexual experience by approximately 17.5 years in schools, neighbourhoods and friendship networks. We examined how much clustering at particular levels could be accounted for by life history predictors and Big Five personality factors. Sexual experience exhibited substantial clustering in friendship networks, while clustering at the level of schools and neighbourhoods was minimal, suggesting a limited role for socio-ecological influences at those levels. While life history predictors did account for some variation in sexual experience, they did not explain clustering in friendship networks. Personality, especially extraversion, explained about a quarter of friends' similarity. After accounting for life history factors and personality, substantial unexplained similarity among friends remained, which may reflect a tendency to associate with similar individuals or the social transmission of behavioural norms.

Life history factors, personality and the social clustering of sexual experience in adolescents

PubMed Central

2016-01-01

Adolescent sexual behaviour may show clustering in neighbourhoods, schools and friendship networks. This study aims to assess how experience with sexual intercourse clusters across the social world of adolescents and whether predictors implicated by life history theory or personality traits can account for its between-individual variation and social patterning. Using data on 2877 adolescents from the Avon Longitudinal Study of Parents and Children, we ran logistic multiple classification models to assess the clustering of sexual experience by approximately 17.5 years in schools, neighbourhoods and friendship networks. We examined how much clustering at particular levels could be accounted for by life history predictors and Big Five personality factors. Sexual experience exhibited substantial clustering in friendship networks, while clustering at the level of schools and neighbourhoods was minimal, suggesting a limited role for socio-ecological influences at those levels. While life history predictors did account for some variation in sexual experience, they did not explain clustering in friendship networks. Personality, especially extraversion, explained about a quarter of friends' similarity. After accounting for life history factors and personality, substantial unexplained similarity among friends remained, which may reflect a tendency to associate with similar individuals or the social transmission of behavioural norms. PMID:27853543

Natural history of idiopathic abducens nerve paresis in a young adult.

PubMed

Hussaindeen, Jameel Rizwana; Mani, Revathy; Rakshit, Archayeeta; Ramasubramanian, Srikanth; Vittal Praveen, Smitha

2016-01-01

The natural history of idiopathic abducens nerve paresis and the role of conservative management such as vision training during the recovery process is not well documented in the literature to the best of our knowledge. This case report presents the natural recovery process of idiopathic abducens nerve paresis in a young adult and the role of vision therapy in the recovery process. Copyright © 2016 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.

Bringing history to life: simulating landmark experiments in psychology.

PubMed

Boynton, David M; Smith, Laurence D

2006-05-01

The course in history of psychology can be challenging for students, many of whom enter it with little background in history and faced with unfamiliar names and concepts. The sheer volume of material can encourage passive memorization unless efforts are made to increase student involvement. As part of a trend toward experiential history, historians of science have begun to supplement their lectures with demonstrations of classic physics experiments as a way to bring the history of science to life. Here, the authors report on computer simulations of five landmark experiments from early experimental psychology in the areas of reaction time, span of attention, and apparent motion. The simulations are designed not only to permit hands-on replication of historically important results but also to reproduce the experimental procedures closely enough that students can gain a feel for the nature of early research and the psychological processes being studied.

Pace of life, predators and parasites: predator-induced life-history evolution in Trinidadian guppies predicts decrease in parasite tolerance.

PubMed

Stephenson, J F; van Oosterhout, C; Cable, J

2015-11-01

A common evolutionary response to predation pressure is increased investment in reproduction, ultimately resulting in a fast life history. Theory and comparative studies suggest that short-lived organisms invest less in defence against parasites than those that are longer lived (the pace of life hypothesis). Combining these tenets of evolutionary theory leads to the specific, untested prediction that within species, populations experiencing higher predation pressure invest less in defence against parasites. The Trinidadian guppy, Poecilia reticulata, presents an excellent opportunity to test this prediction: guppy populations in lower courses of rivers experience higher predation pressure, and as a consequence have evolved faster life histories, than those in upper courses. Data from a large-scale field survey showed that fish infected with Gyrodactylus parasites were of a lower body condition (quantified using the scaled mass index) than uninfected fish, but only in lower course populations. Although the evidence we present is correlational, it suggests that upper course guppies sustain lower fitness costs of infection, i.e. are more tolerant, than lower course guppies. The data are therefore consistent with the pace of life hypothesis of parasite defence allocation, and suggest that life-history traits mediate the indirect effect of predators on the parasites of their prey. © 2015 The Author(s).

Young Adult Identities and Their Pathways: A Developmental and Life Course Model

PubMed Central

Benson, Janel E.; Elder, Glen H.

2013-01-01

Developmental and life course studies of young adult identities have focused on two dimensions, subjective age and psychosocial maturity. This study examines the developmental synchrony of these two processes. In a longitudinal sample of young adults from Add Health (18 to 22), a person-centered analysis of indicators of these dimensions identified four identity profiles. Two depict early and late patterns of identity; the others represent contrasting types of discordance, “pseudo-adult”, subjective age more advanced than maturation level and “anticipatory”, with subjective age less advanced than maturational level. The profiles vary by gender, socioeconomic status, and race-ethnicity as well as by adolescent (ages12–16) pubertal maturation, psychosocial adjustment, and family context. These results provide support for a more holistic, interdisciplinary understanding of adult identity, and show that young adult identities in the Add Health sample follow differentiated paths into the adult years, with largely unknown consequences for the subsequent life course. PMID:21668096

Modeling tradeoffs in avian life history traits and consequences for population growth

USGS Publications Warehouse

Clark, M.E.; Martin, T.E.

2007-01-01

Variation in population dynamics is inherently related to life history characteristics of species, which vary markedly even within phylogenetic groups such as passerine birds. We computed the finite rate of population change (??) from a matrix projection model and from mark-recapture observations for 23 bird species breeding in northern Arizona. We used sensitivity analyses and a simulation model to separate contributions of different life history traits to population growth rate. In particular we focused on contrasting effects of components of reproduction (nest success, clutch size, number of clutches, and juvenile survival) versus adult survival on ??. We explored how changes in nest success or adult survival coupled to costs in other life history parameters affected ?? over a life history gradient provided by our 23 Arizona species, as well as a broader sample of 121 North American passerine species. We further examined these effects for more than 200 passeriform and piciform populations breeding across North America. Model simulations indicate nest success and juvenile survival exert the largest effects on population growth in species with moderate to high reproductive output, whereas adult survival contributed more to population growth in long-lived species. Our simulations suggest that monitoring breeding success in populations across a broad geographic area provides an important index for identifying neotropical migratory populations at risk of serious population declines and a potential method for identifying large-scale mechanisms regulating population dynamics. ?? 2007 Elsevier B.V. All rights reserved.

Population-specific life histories contribute to metapopulation viability

USGS Publications Warehouse

Halsey, Samniqueka J.; Bell, Timothy J.; McEachern, A. Kathryn; Pavlovic, Noel B.

2016-01-01

Restoration efforts can be improved by understanding how variations in life-history traits occur within populations of the same species living in different environments. This can be done by first understanding the demographic responses of natural occurring populations. Population viability analysis continues to be useful to species management and conservation with sensitivity analysis aiding in the understanding of population dynamics. In this study, using life-table response experiments and elasticity analyses, we investigated how population-specific life-history demographic responses contributed to the metapopulation viability of the Federally threatened Pitcher's thistle (Cirsium pitcheri). Specifically, we tested the following hypotheses: (1) Subpopulations occupying different environments within a metapopulation have independent demographic responses and (2) advancing succession results in a shift from a demographic response focused on growth and fecundity to one dominated by stasis. Our results showed that reintroductions had a positive contribution to the metapopulation growth rate as compared to native populations which had a negative contribution. We found no difference in succession on the contribution to metapopulation viability. In addition, we identified distinct population-specific contributions to metapopulation viability and were able to associate specific life-history demographic responses. For example, the positive impact of Miller High Dunes population on the metapopulation growth rate resulted from high growth contributions, whereas increased time of plant in stasis for the State Park Big Blowout population resulted in negative contributions. A greater understanding of how separate populations respond in their corresponding environment may ultimately lead to more effective management strategies aimed at reducing extinction risk. We propose the continued use of sensitivity analyses to evaluate population-specific demographic influences on

Restless Legs Syndrome, Sleep, and Quality of Life among Adolescents and Young Adults

PubMed Central

Silva, Graciela E.; Goodwin, James L.; Vana, Kimberly D.; Vasquez, Monica M.; Wilcox, Peter G.; Quan, Stuart F.

2014-01-01

Objective: Clinical reports in children implicate restless legs syndrome (RLS) with sleep and behavior problems. However, population-based studies on this association in adolescents and young adults are limited. Furthermore, few studies have evaluated the association between symptoms consistent with RLS and quality of life (QoL). Study Design: This cross-sectional study included 214 Caucasian and Hispanic adolescents and young adults aged 12-20 years. Symptoms consistent with RLS were based on four essential criteria and if the symptoms occurred ≥ 5 days/ month. Trouble falling asleep was present if reported “yes, still have the problem.” Quality of life (QoL) was assessed using the Pediatric QoL Inventory. Three summary QoL scores ranging from 0-100 were evaluated; higher scores indicated better QoL. Results: Participants were 50% male and 68.1% Caucasian. Prevalence of RLS was 8.4% (n = 18). RLS was associated with trouble falling asleep (OR = 3.1, p = 0.049), and trouble falling asleep was associated with worse Psychosocial Health scores (Coeff. −5.6, p = 0.004) and Total Scale scores for quality of life (Coeff. −4.6, p = 0.007). Conclusions: The prevalence of symptoms consistent with RLS in this community-based sample of adolescents and young adults, aged 12-20, is comparable to rates reported in older cohorts. Symptoms consistent with RLS may be associated with trouble falling asleep and psychosocial distress that may contribute to a lower health-related quality of life. Citation: Silva GE, Goodwin JL, Vana KD, Vasquez MM, Wilcox PG, Quan SF. Restless legs syndrome, sleep, and quality of life among adolescents and young adults. J Clin Sleep Med 2014;10(7):779-786. PMID:25024656

Evidence of panmixia between sympatric life history forms of coastal cutthroat trout in two lower Columbia River tributaries

USGS Publications Warehouse

Johnson, Jeffrey R.; Baumsteiger, Jason; Zydlewski, Joseph D.; Hudson, J. Michael; Ardren, William R.

2010-01-01

Coastal cutthroat trout Oncorhynchus clarkii clarkii exhibit resident and migratory life history strategies that often occur sympatrically, but the relationship between these forms within a population is poorly characterized. Through use of passive integrated transponder technology, migratory and resident coastal cutthroat trout were identified in two lower Columbia River tributaries (Abernathy Creek and the Chinook River) separated by more than 80 km. Genetic data from 17 highly variable microsatellite loci were used to ascertain the genetic population structure of these life history forms within and between streams. No distinct genetic separation was observed between the life history forms within a stream, as assessed by four different statistical approaches: permutation tests based on the genetic differentiation index F ST, principal components analysis of individuals, analysis of molecular variance, and contingency tests of allele frequency heterogeneity. Genetic differences were an order of magnitude higher between stream samples (F ST > 0.03) than between life history forms within a stream (F ST < 0.003). The contingency test detected allele frequency differences between migratory and resident life history forms in Abernathy Creek (P = 0.001), but this result was influenced more by age-class structure than by reproductive isolation between life history forms. Results are consistent with a single, randomly mating population in each stream producing both migratory and resident life history forms. These data suggest that individual life history strategy in coastal cutthroat trout is predominantly determined by phenotypic plasticity rather than genotype.

The work life and career development of young breast cancer survivors.

PubMed

Raque-Bogdan, Trisha L; Hoffman, Mary Ann; Ginter, Amanda C; Piontkowski, Sarah; Schexnayder, Kelci; White, Rachel

2015-10-01

Breast cancer survivors represent the largest proportion of cancer survivors, and the rate of young breast cancer survivors who are diagnosed before the age of 40 is increasing. Cancer survivorship scholarship has begun to address many aspects of survivors' quality of life, yet the role of work and career issues have been understudied, particularly for young survivors. To explore the work lives and career development of young breast cancer survivors, this study used consensual qualitative research methodology (Hill, Thompson, & Williams, 1997) to analyze data from qualitative interviews with 13 young women diagnosed with breast cancer before the age of 40. The 4 career-related domains that emerged from the data were (a) cancer-related work challenges, (b) coping with cancer-related work challenges, (c) reappraisal of career development after cancer, and (d) components of career and life satisfaction after cancer. Experiencing breast cancer at a young age was viewed by participants as contributing to an increased desire for work to provide a sense of meaning as well as financial security and insurance. Cancer was further viewed as contributing to lost control over career success and work choices, treatment side effects that interfere with work self-efficacy and capabilities, and interpersonal difficulties connecting within and outside of work. Women with more extensive cancer treatment and side effects reported greater work struggles. Despite this, participants' cancer narratives were characterized by a range of coping strategies, including reframing and seeking control, and by evidence of persistence, resilience, and hope. Implications for research and practice are discussed. (c) 2015 APA, all rights reserved).

GENOMIC BASIS OF AGING AND LIFE HISTORY EVOLUTION IN DROSOPHILA MELANOGASTER

PubMed Central

Remolina, Silvia C.; Chang, Peter L.; Leips, Jeff; Nuzhdin, Sergey V.; Hughes, Kimberly A.

2015-01-01

Natural diversity in aging and other life history patterns is a hallmark of organismal variation. Related species, populations, and individuals within populations show genetically based variation in life span and other aspects of age-related performance. Population differences are especially informative because these differences can be large relative to within-population variation and because they occur in organisms with otherwise similar genomes. We used experimental evolution to produce populations divergent for life span and late-age fertility and then used deep genome sequencing to detect sequence variants with nucleotide-level resolution. Several genes and genome regions showed strong signatures of selection, and the same regions were implicated in independent comparisons, suggesting that the same alleles were selected in replicate lines. Genes related to oogenesis, immunity, and protein degradation were implicated as important modifiers of late-life performance. Expression profiling and functional annotation narrowed the list of strong candidate genes to 38, most of which are novel candidates for regulating aging. Life span and early-age fecundity were negatively correlated among populations; therefore the alleles we identified also are candidate regulators of a major life-history trade-off. More generally, we argue that hitchhiking mapping can be a powerful tool for uncovering the molecular bases of quantitative genetic variation. PMID:23106705

Growth and life history variability of the grey reef shark (Carcharhinus amblyrhynchos) across its range

PubMed Central

Bradley, Darcy; Conklin, Eric; Papastamatiou, Yannis P.; McCauley, Douglas J.; Pollock, Kydd; Kendall, Bruce E.; Gaines, Steven D.; Caselle, Jennifer E.

2017-01-01

For broadly distributed, often overexploited species such as elasmobranchs (sharks and rays), conservation management would benefit from understanding how life history traits change in response to local environmental and ecological factors. However, fishing obfuscates this objective by causing complex and often mixed effects on the life histories of target species. Disentangling the many drivers of life history variability requires knowledge of elasmobranch populations in the absence of fishing, which is rarely available. Here, we describe the growth, maximum size, sex ratios, size at maturity, and offer a direct estimate of survival of an unfished population of grey reef sharks (Carcharhinus amblyrhynchos) using data from an eight year tag-recapture study. We then synthesized published information on the life history of C. amblyrhynchos from across its geographic range, and for the first time, we attempted to disentangle the contribution of fishing from geographic variation in an elasmobranch species. For Palmyra’s unfished C. amblyrhynchos population, the von Bertalanffy growth function (VBGF) growth coefficient k was 0.05 and asymptotic length L∞ was 163.3 cm total length (TL). Maximum size was 175.5 cm TL from a female shark, length at maturity was estimated at 116.7–123.2 cm TL for male sharks, maximum lifespan estimated from VBGF parameters was 18.1 years for both sexes combined, and annual survival was 0.74 year-1. Consistent with findings from studies on other elasmobranch species, we found significant intraspecific variability in reported life history traits of C. amblyrhynchos. However, contrary to what others have reported, we did not find consistent patterns in life history variability as a function of biogeography or fishing. Ultimately, the substantial, but not yet predictable variability in life history traits observed for C. amblyrhynchos across its geographic range suggests that regional management may be necessary to set sustainable harvest

Increased Mortality Exposure within the Family Rather than Individual Mortality Experiences Triggers Faster Life-History Strategies in Historic Human Populations

PubMed Central

Störmer, Charlotte; Lummaa, Virpi

2014-01-01

Life History Theory predicts that extrinsic mortality risk is one of the most important factors shaping (human) life histories. Evidence from contemporary populations suggests that individuals confronted with high mortality environments show characteristic traits of fast life-history strategies: they marry and reproduce earlier, have shorter birth intervals and invest less in their offspring. However, little is known of the impact of mortality experiences on the speed of life histories in historical human populations with generally higher mortality risk, and on male life histories in particular. Furthermore, it remains unknown whether individual-level mortality experiences within the family have a greater effect on life-history decisions or family membership explains life-history variation. In a comparative approach using event history analyses, we study the impact of family versus individual-level effects of mortality exposure on two central life-history parameters, ages at first marriage and first birth, in three historical human populations (Germany, Finland, Canada). Mortality experience is measured as the confrontation with sibling deaths within the natal family up to an individual's age of 15. Results show that the speed of life histories is not adjusted according to individual-level mortality experiences but is due to family-level effects. The general finding of lower ages at marriage/reproduction after exposure to higher mortality in the family holds for both females and males. This study provides evidence for the importance of the family environment for reproductive timing while individual-level mortality experiences seem to play only a minor role in reproductive life history decisions in humans. PMID:24421897

Increased mortality exposure within the family rather than individual mortality experiences triggers faster life-history strategies in historic human populations.

PubMed

Störmer, Charlotte; Lummaa, Virpi

2014-01-01

Life History Theory predicts that extrinsic mortality risk is one of the most important factors shaping (human) life histories. Evidence from contemporary populations suggests that individuals confronted with high mortality environments show characteristic traits of fast life-history strategies: they marry and reproduce earlier, have shorter birth intervals and invest less in their offspring. However, little is known of the impact of mortality experiences on the speed of life histories in historical human populations with generally higher mortality risk, and on male life histories in particular. Furthermore, it remains unknown whether individual-level mortality experiences within the family have a greater effect on life-history decisions or family membership explains life-history variation. In a comparative approach using event history analyses, we study the impact of family versus individual-level effects of mortality exposure on two central life-history parameters, ages at first marriage and first birth, in three historical human populations (Germany, Finland, Canada). Mortality experience is measured as the confrontation with sibling deaths within the natal family up to an individual's age of 15. Results show that the speed of life histories is not adjusted according to individual-level mortality experiences but is due to family-level effects. The general finding of lower ages at marriage/reproduction after exposure to higher mortality in the family holds for both females and males. This study provides evidence for the importance of the family environment for reproductive timing while individual-level mortality experiences seem to play only a minor role in reproductive life history decisions in humans.

Twelve fundamental life histories evolving through allocation-dependent fecundity and survival.

PubMed

Johansson, Jacob; Brännström, Åke; Metz, Johan A J; Dieckmann, Ulf

2018-03-01

An organism's life history is closely interlinked with its allocation of energy between growth and reproduction at different life stages. Theoretical models have established that diminishing returns from reproductive investment promote strategies with simultaneous investment into growth and reproduction (indeterminate growth) over strategies with distinct phases of growth and reproduction (determinate growth). We extend this traditional, binary classification by showing that allocation-dependent fecundity and mortality rates allow for a large diversity of optimal allocation schedules. By analyzing a model of organisms that allocate energy between growth and reproduction, we find twelve types of optimal allocation schedules, differing qualitatively in how reproductive allocation increases with body mass. These twelve optimal allocation schedules include types with different combinations of continuous and discontinuous increase in reproduction allocation, in which phases of continuous increase can be decelerating or accelerating. We furthermore investigate how this variation influences growth curves and the expected maximum life span and body size. Our study thus reveals new links between eco-physiological constraints and life-history evolution and underscores how allocation-dependent fitness components may underlie biological diversity.

Life-History and Developmental Antecedents of Female Vocational Preferences.

ERIC Educational Resources Information Center

Reichel, Laura S.; Muchinsky, Paul M.

1995-01-01

A group of 296 female undergraduates completed the Strong Interest Inventory, Biographical Questionnaire, Bem Sex-Role Inventory, and Self-Esteem Inventory. Life history was a better predictor of vocational interests than either sex-role orientation or self-esteem. The only significant exception was that Femininity correlated with interest in…

Religious People Are Trusted Because They Are Viewed as Slow Life-History Strategists.

PubMed

Moon, Jordan W; Krems, Jaimie Arona; Cohen, Adam B

2018-06-01

Religious people are more trusted than nonreligious people. Although most theorists attribute these perceptions to the beliefs of religious targets, religious individuals also differ in behavioral ways that might cue trust. We examined whether perceivers might trust religious targets more because they heuristically associate religion with slow life-history strategies. In three experiments, we found that religious targets are viewed as slow life-history strategists and that these findings are not the result of a universally positive halo effect; that the effect of target religion on trust is significantly mediated by the target's life-history traits (i.e., perceived reproductive strategy); and that when perceivers have direct information about a target's reproductive strategy, their ratings of trust are driven primarily by his or her reproductive strategy, rather than religion. These effects operate over and above targets' belief in moralizing gods and offer a novel theoretical perspective on religion and trust.

Life history and status of shortnose sturgeon (Acipenser brevirostrum) in the Potomac River

USGS Publications Warehouse

Kieffer, Micah

2009-01-01

We collected the first life history information on shortnose sturgeon (Acipenser brevirostrum) in any of the rivers to Chesapeake Bay, the geographic center of the species range. In the Potomac River, two telemetry-tagged adult females used 124 km of river: a saltwater/freshwater reach at river km (rkm) 63-141 was the foraging-wintering concentration area, and one female migrated to spawn at rkm 187 in Washington, DC. The spawning migration explained the life history context of an adult captured 122 years ago in Washington, DC, supporting the idea that a natal population once lived in the river. Repeated homing migrations to foraging and wintering areas suggested the adults were residents, not transient coastal migrants. All habitats that adults need to complete life history are present in the river. The Potomac River shortnose sturgeon offers a rare opportunity to learn about the natural rebuilding of a sturgeon population.

Worse quality of life in young and recently diagnosed breast cancer survivors compared with female survivors of other cancers: A cross-sectional study.

PubMed

Li, Jingmei; Humphreys, Keith; Eriksson, Mikael; Dar, Huma; Brandberg, Yvonne; Hall, Per; Czene, Kamila

2016-12-01

Literature focusing on health-related quality of life (HRQoL) by cancer site among women only is scarce. This study examines HRQoL of breast cancer (BC) survivors compared with female survivors of other cancers, and to understand which subgroups of BC survivors were particularly at risk of reduced HRQoL. We placed emphasis on young (<50 years) and recently diagnosed (≤5 years) survivors, where the deficits in HRQoL were most pronounced. The cross-sectional study consisted of 2,224 BC survivors, 8,504 non-cancer controls and 2,205 other cancer survivors in the Karma study. We examined HRQoL differences using linear regression analyses in the whole cohort and in a subset of young and recently diagnosed BC survivors (n = 242) and female survivors of other cancers (n = 140) with comparable ages at diagnosis (43.6 vs 43.6, p = 0.917) and time since diagnosis (2.3 vs 2.8 years, p < 0.001). HRQoL was assessed using the EORTC QLQ-C30 questionnaire. While only cognitive functioning was significantly compromised in BC survivors compared with survivors of other cancers when women of all ages were included, young BC survivors reported significantly lower HRQoL on multiple functional scales (global quality of life, emotional, role, social and cognitive functioning) and experienced more fatigue and insomnia. BC survivors with any prior medical history of mental disorders reported poorer HRQoL than those without such a history. We also observed a close-knit relationship between tumor and treatment characteristics. BC survivors perform poorly in HRQoL in comparison with female survivors of other cancers. Our results emphasize the importance of age- and gender-appropriate comparison groups. © 2016 UICC.

History of major depressive disorder prospectively predicts worse quality of life in women with breast cancer.

PubMed

Jim, Heather S L; Small, Brent J; Minton, Susan; Andrykowski, Michael; Jacobsen, Paul B

2012-06-01

Data are scarce about whether past history of major depressive disorder in the absence of current depression places breast cancer patients at risk for worse quality of life. The current study prospectively examined quality of life during chemotherapy in breast cancer patients with a history of resolved major depressive disorder (n = 29) and no history of depression (n = 144). Women with Stages 0-II breast cancer were assessed prior to and at the completion of chemotherapy. Major depressive disorder was assessed via structured interview and quality of life with the SF-36. Patients with past major depressive disorder displayed greater declines in physical functioning relative to patients with no history of depression (p ≤ 0.01). Findings suggest that breast cancer patients with a history of resolved major depressive disorder are at increased risk for declines in physical functioning during chemotherapy relative to patients with no history of depression.

Imitative and Direct Learning as Interacting Factors in Life History Evolution.

PubMed

Bullinaria, John A

2017-01-01

The idea that lifetime learning can have a significant effect on life history evolution has recently been explored using a series of artificial life simulations. These involved populations of competing individuals evolving by natural selection to learn to perform well on simplified abstract tasks, with the learning consisting of identifying regularities in their environment. In reality, there is more to learning than that type of direct individual experience, because it often includes a substantial degree of social learning that involves various forms of imitation of what other individuals have learned before them. This article rectifies that omission by incorporating memes and imitative learning into revised versions of the previous approach. To do this reliably requires formulating and testing a general framework for meme-based simulations that will enable more complete investigations of learning as a factor in any life history evolution scenarios. It does that by simulating imitative information transfer in terms of memes being passed between individuals, and developing a process for merging that information with the (possibly inconsistent) information acquired by direct experience, leading to a consistent overall body of learning. The proposed framework is tested on a range of learning variations and a representative set of life history factors to confirm the robustness of the approach. The simulations presented illustrate the types of interactions and tradeoffs that can emerge, and indicate the kinds of species-specific models that could be developed with this approach in the future.

The nature and dynamics of world religions: a life-history approach.

PubMed

Baumard, Nicolas; Chevallier, Coralie

2015-11-07

In contrast with tribal and archaic religions, world religions are characterized by a unique emphasis on extended prosociality, restricted sociosexuality, delayed gratification and the belief that these specific behaviours are sanctioned by some kind of supernatural justice. Here, we draw on recent advances in life history theory to explain this pattern of seemingly unrelated features. Life history theory examines how organisms adaptively allocate resources in the face of trade-offs between different life-goals (e.g. growth versus reproduction, exploitation versus exploration). In particular, recent studies have shown that individuals, including humans, adjust their life strategy to the environment through phenotypic plasticity: in a harsh environment, organisms tend to adopt a 'fast' strategy, pursuing smaller but more certain benefits, while in more affluent environments, organisms tend to develop a 'slow' strategy, aiming for larger but less certain benefits. Reviewing a range of recent research, we show that world religions are associated with a form of 'slow' strategy. This framework explains both the promotion of 'slow' behaviours such as altruism, self-regulation and monogamy in modern world religions, and the condemnation of 'fast' behaviours such as selfishness, conspicuous sexuality and materialism. This ecological approach also explains the diffusion pattern of world religions: why they emerged late in human history (500-300 BCE), why they are currently in decline in the most affluent societies and why they persist in some places despite this overall decline. © 2015 The Author(s).

The nature and dynamics of world religions: a life-history approach

PubMed Central

Baumard, Nicolas; Chevallier, Coralie

2015-01-01

In contrast with tribal and archaic religions, world religions are characterized by a unique emphasis on extended prosociality, restricted sociosexuality, delayed gratification and the belief that these specific behaviours are sanctioned by some kind of supernatural justice. Here, we draw on recent advances in life history theory to explain this pattern of seemingly unrelated features. Life history theory examines how organisms adaptively allocate resources in the face of trade-offs between different life-goals (e.g. growth versus reproduction, exploitation versus exploration). In particular, recent studies have shown that individuals, including humans, adjust their life strategy to the environment through phenotypic plasticity: in a harsh environment, organisms tend to adopt a ‘fast' strategy, pursuing smaller but more certain benefits, while in more affluent environments, organisms tend to develop a ‘slow' strategy, aiming for larger but less certain benefits. Reviewing a range of recent research, we show that world religions are associated with a form of ‘slow' strategy. This framework explains both the promotion of ‘slow' behaviours such as altruism, self-regulation and monogamy in modern world religions, and the condemnation of ‘fast' behaviours such as selfishness, conspicuous sexuality and materialism. This ecological approach also explains the diffusion pattern of world religions: why they emerged late in human history (500–300 BCE), why they are currently in decline in the most affluent societies and why they persist in some places despite this overall decline. PMID:26511055

Pathogen and host genotype differently affect pathogen fitness through their effects on different life-history stages.

PubMed

Bruns, Emily; Carson, Martin; May, Georgiana

2012-08-02

Adaptation of pathogens to their hosts depends critically on factors affecting pathogen reproductive rate. While pathogen reproduction is the end result of an intricate interaction between host and pathogen, the relative contributions of host and pathogen genotype to variation in pathogen life history within the host are not well understood. Untangling these contributions allows us to identify traits with sufficient genetic variation for selection to act and to identify mechanisms of coevolution between pathogens and their hosts. We investigated the effects of pathogen and host genotype on three life-history components of pathogen fitness; infection efficiency, latent period, and sporulation capacity, in the oat crown rust fungus, Puccinia coronata f.sp. avenae, as it infects oats (Avena sativa). We show that both pathogen and host genotype significantly affect total spore production but do so through their effects on different life-history stages. Pathogen genotype has the strongest effect on the early stage of infection efficiency, while host genotype most strongly affects the later life-history stages of latent period and sporulation capacity. In addition, host genotype affected the relationship between pathogen density and the later life-history traits of latent period and sporulation capacity. We did not find evidence of pathogen-by-host genotypic (GxG) interactions. Our results illustrate mechanisms by which variation in host populations will affect the evolution of pathogen life history. Results show that different pathogen life-history stages have the potential to respond differently to selection by host or pathogen genotype and suggest mechanisms of antagonistic coevolution. Pathogen populations may adapt to host genotypes through increased infection efficiency while their plant hosts may adapt by limiting the later stages of pathogen growth and spore production within the host.

Issues Using the Life History Calendar in Disability Research

PubMed Central

Scott, Tiffany N.; Harrison, Tracie

2011-01-01

Background Overall, there is a dearth of research reporting mixed-method data collection procedures using the LHC within disability research. Objective This report provides practical knowledge on use of the life history calendar (LHC) from the perspective of a mixed-method life history study of mobility impairment situated within a qualitative paradigm. Methods In this paper the method related literature referring to the LHC was reviewed along with its epistemological underpinnings. Further, the uses of the LHC in disability research were illustrated using preliminary data from reports of disablement in Mexican American and Non-Hispanic White women with permanent mobility impairment. Results From our perspective, the LHC was most useful when approached from an interpretive paradigm when gathering data from women of varied ethnic and socioeconomic strata. While we found the LHC the most useful tool currently available for studying disablement over the life course, there were challenges associated with its use. The LHC required extensive interviewer training. In addition, large segments of time were needed for completion depending on the type of participant responses. Conclusions Researchers planning to conduct a disability study may find our experience using the LHC valuable for anticipating issues that may arise when the LHC is used in mixed-method research. PMID:22014674

Cross-cultural Comparison of Learning in Human Hunting : Implications for Life History Evolution.

PubMed

MacDonald, Katharine

2007-12-01

This paper is a cross-cultural examination of the development of hunting skills and the implications for the debate on the role of learning in the evolution of human life history patterns. While life history theory has proven to be a powerful tool for understanding the evolution of the human life course, other schools, such as cultural transmission and social learning theory, also provide theoretical insights. These disparate theories are reviewed, and alternative and exclusive predictions are identified. This study of cross-cultural regularities in how children learn hunting skills, based on the ethnographic literature on traditional hunters, complements existing empirical work and highlights future areas for investigation.

Influence of History of Brain Disease or Brain Trauma on Psychopathological Abnormality in Young Male in Korea : Analysis of Multiphasic Personal Inventory Test

PubMed Central

Paik, Ho Kyu; Oh, Chang-Hyun; Choi, Kang; Kim, Chul-Eung; Yoon, Seung Hwan

2011-01-01

Objective The purpose of this study is to confirm whether brain disease or brain trauma actually affect psychopathology in young male group in Korea. Methods The authors manually reviewed the result of Korean military multiphasic personal inventory (KMPI) in the examination of conscription in Korea from January 2008 to May 2010. There were total 237 young males in this review. Normal volunteers group (n=150) was composed of those who do not have history of brain disease or brain trauma. Brain disease group (n=33) was consisted of those with history of brain disease. Brain trauma group (n=54) was consisted of those with history of brain trauma. The results of KMPI in each group were compared. Results Abnormal results of KMPI were found in both brain disease and trauma groups. In the brain disease group, higher tendencies of faking bad response, anxiety, depression, somatization, personality disorder, schizophrenic and paranoid psychopathy was observed and compared to the normal volunteers group. In the brain trauma group, higher tendencies of faking-good, depression, somatization and personality disorder was observed and compared to the normal volunteers group. Conclusion Young male with history of brain disease or brain trauma may have higher tendencies to have abnormal results of multiphasic personal inventory test compared to young male without history of brain disease or brain trauma, suggesting that damaged brain may cause psychopathology in young male group in Korea. PMID:22053230

Plant Species Loss Affects Life-History Traits of Aphids and Their Parasitoids

PubMed Central

Petermann, Jana S.; Roscher, Christiane; Weigelt, Alexandra; Weisser, Wolfgang W.; Schmid, Bernhard

2010-01-01

The consequences of plant species loss are rarely assessed in a multi-trophic context and especially effects on life-history traits of organisms at higher trophic levels have remained largely unstudied. We used a grassland biodiversity experiment and measured the effects of two components of plant diversity, plant species richness and the presence of nitrogen-fixing legumes, on several life-history traits of naturally colonizing aphids and their primary and secondary parasitoids in the field. We found that, irrespective of aphid species identity, the proportion of winged aphid morphs decreased with increasing plant species richness, which was correlated with decreasing host plant biomass. Similarly, emergence proportions of parasitoids decreased with increasing plant species richness. Both, emergence proportions and proportions of female parasitoids were lower in plots with legumes, where host plants had increased nitrogen concentrations. This effect of legume presence could indicate that aphids were better defended against parasitoids in high-nitrogen environments. Body mass of emerged individuals of the two most abundant primary parasitoid species was, however, higher in plots with legumes, suggesting that once parasitoids could overcome aphid defenses, they could profit from larger or more nutritious hosts. Our study demonstrates that cascading effects of plant species loss on higher trophic levels such as aphids, parasitoids and secondary parasitoids begin with changed life-history traits of these insects. Thus, life-history traits of organisms at higher trophic levels may be useful indicators of bottom-up effects of plant diversity on the biodiversity of consumers. PMID:20700511

Expression of lysozyme in the life history of the house fly (Musca domestica l.).

PubMed

Nayduch, Dana; Joyner, Chester

2013-07-01

From egg to adult, all life history stages of house flies associate with septic environments teeming with bacteria. House fly lysozyme was first identified in the larval midgut, where it is used for digestion of microbe-rich meals because of its broad-spectrum activity against gram-positive and gram-negative bacteria as well as fungi. This study aimed to determine the temporal expression of lysozyme in the life history of house flies (from egg through adults) on both the mRNA and protein level, and to determine the tissue-specific expression of lysozyme in adult flies induced by feeding Staphylococcus aureus. From 30-min postoviposition through adulthood, all life history stages of the house fly express lysozyme on the mRNA level. In adult flies, lysozyme is expressed both locally in the alimentary canal and systemically in the fat body. Interestingly, we found that during the normal life history of flies, lysozyme protein was only detected in larval stages and older adults, likely because of ingestion of immune-stimulating levels of bacteria, not experienced during egg, pupa, and teneral adult stages. Constitutive expression on the mRNA level implies that this effector is a primary defense molecule in all stages of the house fly life history, and that a mechanism for posttranscriptional control of mature lysozyme enzyme expression may be present. Lysozyme active enzyme primarily serves both a digestive and defensive function in larval and adult flies, and may be a key player in the ability of Musca domestica L. to thrive in microbe-rich environments.

Evolutionary ecology of endocrine-mediated life-history variation in the garter snake Thamnophis elegans.

PubMed

Sparkman, Amanda M; Vleck, Carol M; Bronikowski, Anne M

2009-03-01

The endocrine system plays an integral role in the regulation of key life-history traits. Insulin-like growth factor-1 (IGF-1) is a hormone that promotes growth and reproduction, and it has been implicated in the reduction of lifespan. IGF-1 is also capable of responding plastically to environmental stimuli such as resource availability and temperature. Thus pleiotropic control of life-history traits by IGF-1 could provide a mechanism for the evolution of correlated life-history traits in a new or changing environment. An ideal system in which to investigate the role of IGF-1 in life-history evolution exists in two ecotypes of the garter snake Thamnophis elegans, which derive from a single recent ancestral source but have evolved genetically divergent life-history characteristics. Snakes from meadow populations near Eagle Lake, California (USA) exhibit slower growth rates, lower annual reproductive output, and longer median adult lifespans relative to populations along the lakeshore. We hypothesized that the IGF-1 system has differentiated between these ecotypes and can account for increased growth and reproduction and reduced survival in lakeshore vs. meadow snakes. We tested for a difference in plasma IGF-1 levels in free-ranging snakes from replicate populations of each ecotype over three years. IGF-1 levels were significantly associated with adult body size, reproductive output, and season in a manner that reflects established differences in prey ecology and age/size-specific reproduction between the ecotypes. These findings are discussed in the context of theoretical expectations for a tradeoff between reproduction and lifespan that is mediated by pleiotropic endocrine mechanisms.

A review of Ruffe (Gymnocephalus cernuus) life history and implications for spread

EPA Science Inventory

Ruffe (Gymnocephalus cernuus) are among the most widespread fish invaders in Lake Superior. The objective of this study was to gather information on the complete life cycle of Ruffe in both their native and non-native ranges to characterize their life history strategies. A study ...

Early reproductive maturity among Pumé foragers: Implications of a pooled energy model to fast life histories.

PubMed

Kramer, Karen L; Greaves, Russell D; Ellison, Peter T

2009-01-01

Life history theory places central importance on relationships between ontogeny, reproduction, and mortality. Fast human life histories have been theoretically and empirically associated with high mortality regimes. This relationship, however, poses an unanswered question about energy allocation. In epidemiologically stressful environments, a greater proportion of energy is allocated to immune function. If growth and maintenance are competing energetic expenditures, less energy should be available for growth, and the mechanism to sustain rapid maturation remains unclear. The human pattern of extended juvenile provisioning and resource sharing may provide an important source of variation in energy availability not predicted by tradeoff models that assume independence at weaning. We consider a group of South American foragers to evaluate the effects that pooled energy budgets may have on early reproduction. Despite growing up in an environment with distinct seasonal under-nutrition, harsh epidemiological conditions, and no health care, Pumé girls mature quickly and initiate childbearing in their midteens. Pooled energy budgets compensate for the low productivity of girls not only through direct food transfers but importantly by reducing energy they would otherwise expend in foraging activities to meet metabolic requirements. We suggest that pooled energy budgets affect energy availability at both extrinsic and intrinsic levels. Because energy budgets are pooled, Pumé girls and young women are buffered from environmental downturns and can maximize energy allocated to growth completion and initiate reproduction earlier than a traditional bound-energy model would predict. 2009 Wiley-Liss, Inc.

Contrasting latitudinal patterns of life-history divergence in two genera of new world thrushes (Turdinae)

USGS Publications Warehouse

Boyce, Andy J.; Martin, Thomas E.

2017-01-01

Several long-standing hypotheses have been proposed to explain latitudinal patterns of life-history strategies. Here, we test predictions of four such hypotheses (seasonality, food limitation, nest predation and adult survival probability) by examining life-history traits and age-specific mortality rates of several species of thrushes (Turdinae) based on field studies at temperate and tropical sites and data gathered from the literature. Thrushes in the genus Catharus showed the typical pattern of slower life-history strategies in the tropics while co-occuring Turdus thrushes differed much less across latitudes. Seasonality is a broadly accepted hypothesis for latitudinal patterns, but the lack of concordance in latitudinal patterns between co-existing genera that experience the same seasonal patterns suggests seasonality cannot fully explain latitudinal trait variation in thrushes. Nest-predation also could not explain patterns based on our field data and literature data for these two genera. Total feeding rates were similar, and per-nestling feeding rates were higher at tropical latitudes in both genera, suggesting food limitation does not explain trait differences in thrushes. Latitudinal patterns of life histories in these two genera were closely associated with adult survival probability. Thus, our data suggest that environmental influences on adult survival probability may play a particularly strong role in shaping latitudinal patterns of life-history traits.

Effects of stressful life events in young black men with high blood pressure.

PubMed

Han, Hae-Ra; Kim, Miyong T; Rose, Linda; Dennison, Cheryl; Bone, Lee; Hill, Martha N

2006-01-01

1) To describe stressful life events as experienced by a sample of young Black men with high blood pressure (HBP) living in inner-city Baltimore, Maryland; and 2) to examine the effect of cumulative stressful life events on substance use, depression, and quality of life. Data were obtained over 48 months by interview from 210 men in an HBP management study. Stressors repeatedly occurring over time included death of family member or close friend (65.2%), having a new family member (32.9%), change in residence (31.4%), difficulty finding a job (24.3%), and fired or laid off from work (17.6%). Involvement with crime or legal matters was reported at least twice during the 48 months by 33.3% of men. When a cumulative stressful life events score was calculated by summing the number of events experienced at 6-month points over 48 months and tested for its relationship with the health outcomes, the findings of multivariate analyses revealed significant associations between cumulative life stressors and depression and quality of life. No significant relationship was found between stressful life events and substance use. The results suggest that cumulative stressful life events have a negative effect on mental health and quality of life in young Black men with HBP. Future study should focus on developing interventions to assist individuals in managing distress related to stressful events with necessary community resources.

Student Life in Canadian Universities: The Lessons of History.

ERIC Educational Resources Information Center

Axelrod, Paul

1990-01-01

The relationship between the history of the student and contemporary student life is explored, and enduring patterns are identified in three areas: the social origins of students; student culture and activism; and the perceived academic quality of students. It is concluded that students should be heard and taken more seriously. (MSE)

Health-related quality of life in young men with testicular cancer: validation of the Cancer Assessment for Young Adults (CAYA).

PubMed

Hoyt, Michael A; Cano, Stefan J; Saigal, Christopher S; Stanton, Annette L

2013-12-01

Patient-reported outcome instruments are needed to measure health-related quality of life (HRQOL) in young adults with cancer. The purpose of this project was to establish a conceptual model and measurement instrument for assessment of HRQOL in young men with testicular cancer. Patient interviews and a literature review were used to develop a conceptual framework of biopsychosocial domains of cancer-related quality of life and an initial pool of questionnaire items. Items were piloted and refined. Revised items were administered to a sample (N = 171) of young (ages 18-29) men with testicular cancer and repeated 4 weeks later. Rasch measurement methods guided item reduction and scale construction. Traditional psychometric analyses were also performed to allow for comparison with existing measures. The conceptual framework included seven biopsychosocial domains: physical, sexual, intrapersonal, cognitive-emotional, social-relational, educational-vocational-avocational, and spiritual to form independent scales of the resulting questionnaire, the Cancer Assessment for Young Adults-Testicular (CAYA-T). Each scale fulfilled Rasch and traditional psychometric criteria (i.e., person separation index, 0.34-0.82; Cronbach's alpha, 0.70-0.91; and an expected pattern of convergent and discriminant validity correlations). The CAYA-T can be used to assess HRQOL across a comprehensive set of domains as identified by young men with cancer. It passes strict psychometric criteria and has potential as a useful research and clinical tool. The CAYA-T has potential research and clinical value for addressing inter-related aspects of HRQOL in young adult men with cancer. The measure may assist with assessing and monitoring HRQOL across a range of domains and contributing to more comprehensive assessment of biopsychosocial needs of young adults.

Neuroethology and life history adaptations of the elasmobranch electric sense.

PubMed

Sisneros, Joseph A; Tricas, Timothy C

2002-01-01

The electric sense of elasmobranch fishes (sharks and rays) is an important sensory modality known to mediate the detection of bioelectric stimuli. Although the best known function for the use of the elasmobranch electric sense is prey detection, relatively few studies have investigated other possible biological functions. Here, we review recent studies that demonstrate the elasmobranch electrosensory system functions in a wide number of behavioral contexts including social, reproductive and anti-predator behaviors. Recent work on non-electrogenic stingrays demonstrates that the electric sense is used during reproduction and courtship for conspecific detection and localization. Electrogenic skates may use their electrosensory encoding capabilities and electric organ discharges for communication during social and reproductive interactions. The electric sense may also be used to detect and avoid predators during early life history stages in many elasmobranch species. Embryonic clearnose skates demonstrate a ventilatory freeze response when a weak low-frequency electric field is imposed upon the egg capsule. Peak frequency sensitivity of the peripheral electrosensory system in embryonic skates matches the low frequencies of phasic electric stimuli produced by natural fish egg-predators. Neurophysiology experiments reveal that electrosensory tuning changes across the life history of a species and also seasonally due to steroid hormone changes during the reproductive season. We argue that the ontogenetic and seasonal variation in electrosensory tuning represent an adaptive electrosensory plasticity that may be common to many elasmobranchs to enhance an individual's fitness throughout its life history.

Corticosterone and pace of life in two life-history ecotypes of the garter snake Thamnophis elegans.

PubMed

Palacios, Maria G; Sparkman, Amanda M; Bronikowski, Anne M

2012-02-01

Glucocorticoids are main candidates for mediating life-history trade-offs by regulating the balance between current reproduction and survival. It has been proposed that slow-living organisms should show higher stress-induced glucocorticoid levels that favor self-maintenance rather than current reproduction when compared to fast-living organisms. We tested this hypothesis in replicate populations of two ecotypes of the garter snake (Thamnophis elegans) that exhibit slow and fast pace of life strategies. We subjected free-ranging snakes to a capture-restraint protocol and compared the stress-induced corticosterone levels between slow- and fast-living snakes. We also used a five-year dataset to assess whether baseline corticosterone levels followed the same pattern as stress-induced levels in relation to pace of life. In accordance with the hypothesis, slow-living snakes showed higher stress-induced corticosterone levels than fast-living snakes. Baseline corticosterone levels showed a similar pattern with ecotype, although differences depended on the year of study. Overall, however, levels of glucocorticoids are higher in slow-living than fast-living snakes, which should favor self-maintenance and survival at the expense of current reproduction. The results of the present study are the first to relate glucocorticoid levels and pace of life in a reptilian system and contribute to our understanding of the physiological mechanisms involved in life-history evolution. Copyright © 2011 Elsevier Inc. All rights reserved.

History of Major Depressive Disorder Prospectively Predicts Worse Quality of Life in Women with Breast Cancer

PubMed Central

Small, Brent J.; Minton, Susan; Andrykowski, Michael; Jacobsen, Paul B.

2012-01-01

Background Data are scarce about whether past history of major depressive disorder in the absence of current depression places breast cancer patients at risk for worse quality of life. Purpose The current study prospectively examined quality of life during chemotherapy in breast cancer patients with a history of resolved major depressive disorder (n=29) and no history of depression (n=144). Methods Women with Stages 0–II breast cancer were assessed prior to and at the completion of chemotherapy. Major depressive disorder was assessed via structured interview and quality of life with the SF-36. Results Patients with past major depressive disorder displayed greater declines in physical functioning relative to patients with no history of depression (p≤0.01). Conclusions Findings suggest that breast cancer patients with a history of resolved major depressive disorder are at increased risk for declines in physical functioning during chemotherapy relative to patients with no history of depression. PMID:22167580

Stressful life events increase aggression and alcohol use in young carriers of the GABRA2 rs279826/rs279858 A-allele.

PubMed

Kiive, Evelyn; Laas, Kariina; Vaht, Mariliis; Veidebaum, Toomas; Harro, Jaanus

2017-08-01

Research of GABRA2 gene in alcohol use and impulse control suggests its role in aggressive behaviour. The purpose of the present study was to examine the effects of GABRA2 genotype and stressful life events on aggressive behaviour, alcohol use frequency and occurrence of alcohol use disorder in a population representative sample of adolescents followed up from third grade to 25 years of age. The sample consisted of the younger cohort of the longitudinal Estonian Children Personality, Behaviour and Health Study. Aggressive behaviour was rated with the activity scale of af Klinteberg, Illinois Bully Scale and Buss-Perry Aggression Questionnaire. Stressful life events and alcohol use were self-reported. Life history of aggression and lifetime occurrence of psychiatric disorders were estimated in a structured interview. The sample was genotyped for GABRA2 rs279826 and rs279858 polymorphisms that are in strong linkage disequilibrium and yielded very similar findings: Higher number of stressful life events reported at age 15 was associated with increased fighting in A-allele carriers, but not in GG homozygotes. At age 25, A-allele carriers with more stressful life events scored higher on physical aggression than those with less stress, and this was also observed regarding life history of aggression. A-allele carriers exposed to higher stress had consumed alcoholic beverages more frequently at age 15, and by age 25, they had alcohol use disorder with higher prevalence. The results of the present study suggest that the GABRA2 genotype interacts with stress in young people with impact on the development of alcohol use and aggressive behaviour. Copyright © 2017 Elsevier B.V. and ECNP. All rights reserved.

Life history and status of shortnose sturgeon (Acipenser brevirostrum) in the potomac river

USGS Publications Warehouse

Kynard, B.; Breece, M.; Atcheson, M.; Kieffer, M.; Mangold, M.

2009-01-01

We collected the first life history information on shortnose sturgeon (Acipenser brevirostrum) in any of the rivers to Chesapeake Bay, the geographic center of the species range. In the Potomac River, two telemetry-tagged adult females used 124 km of river: A saltwater/freshwater reach at river km (rkm) 63-141 was the foraging-wintering concentration area, and one female migrated to spawn at rkm 187 in Washington, DC. The spawning migration explained the life history context of an adult captured 122 years ago in Washington, DC, supporting the idea that a natal population once lived in the river. Repeated homing migrations to foraging and wintering areas suggested the adults were residents, not transient coastal migrants. All habitats that adults need to complete life history are present in the river. The Potomac River shortnose sturgeon offers a rare opportunity to learn about the natural rebuilding of a sturgeon population. ?? 2009 Blackwell Verlag, Berlin.

A Brief History of Family Life Education in Romania

ERIC Educational Resources Information Center

Momanu, Mariana; Popa, Nicoleta Laura; Samoila, Magda-Elena

2018-01-01

Starting from the state of conceptual diversity, semantic ambiguity, and poor connection of family life education practices to current policies and theoretical models in Romania, our study aims at understanding the underlying meanings of these issues by recourse to the history of approaches in the field. To this purpose, we carried out a…

Contributions of dynamic environmental signals during life-cycle transitions to early life-history traits in lodgepole pine (Pinus contorta Dougl.)

NASA Astrophysics Data System (ADS)

Liu, Y.; Wang, T.; El-Kassaby, Y. A.

2015-08-01

Environmental signals are important triggers in the life-cycle transitions and play a crucial role in the life-history evolution. Yet, very little is known about the leading ecological factors contributing to the variations of life-history traits in perennial plants. This paper explores both the causes and consequences for the evolution of life-history traits (i.e., seed dormancy and size) in lodgepole pine (Pinus contorta Dougl.) across British Columbia (B.C.), Canada. We selected 83 logepole pine populations covering 22 ecosystem zones of B.C. and through their geographic coordinate, 197 climatic variables were generated accordingly for the reference (1961-1990) and future (2041-2070) periods. We found that dynamic climatic variables rather than constant geographic variables are the true environmental driving forces in seed dormancy and size variations and thus provide reliable predictors in response to global climate change. Evapotranspiration and precipitation in the plant-to-seed chronology are the most critical climate variables for seed dormancy and size variations, respectively. Hence, we predicted that levels of seed dormancy in lodgepole pine would increase across large tracts of B.C. in 2050s. Winter-chilling is able to increase the magnitude of life-history plasticity and lower the bet-hedge strategy in the seed-to-plant transition; however, winter-chilling is likely to be insufficient in the north of 49° N in 2050s, which may delay germination while unfavourable conditions during dry summers may result in adverse consequences in the survival of seedlings owing to extended germination span.

The Teacher I Wish to Be: Exploring the Influence of Life Histories on Student Teacher Idealised Identities

ERIC Educational Resources Information Center

Furlong, Catherine

2013-01-01

This paper examines the influence of life histories and apprenticeship of observation on the formation of student teachers' idealised identities. The life histories of 15 student teachers are decoded. Through eliciting from the student teachers the teacher they wish to be, the paper focuses on the interplay between the personal histories and ideal…

Sharing stories: life history narratives in stuttering research.

PubMed

Kathard, H

2001-01-01

The life experiences of people who stutter (PWS) have not featured prominently in research. Historically, the profession of speech and language therapy has amassed data and developed its theory of stuttering within a positivistic frame. As a consequence, the existing over-arching theory of research and practice does not engage holistically with the dynamic personal, socio-cultural and political contexts of the individual who stutters. Therefore a conceptual shift is required in ontology, epistemology and methodology underpinning the knowledge construction process. The use of the life history narratives as a research tool is promoted. An exploratory study of a single participant is presented to illuminate the methodological approach and emerging theoretical constructs.

Life-history diversity and its importance to population stability and persistence of a migratory fish: steelhead in two large North American watersheds.

PubMed

Moore, Jonathan W; Yeakel, Justin D; Peard, Dean; Lough, Jeff; Beere, Mark

2014-09-01

Life-history strategies can buffer individuals and populations from environmental variability. For instance, it is possible that asynchronous dynamics among different life histories can stabilize populations through portfolio effects. Here, we examine life-history diversity and its importance to stability for an iconic migratory fish species. In particular, we examined steelhead (Oncorhynchus mykiss), an anadromous and iteroparous salmonid, in two large, relatively pristine, watersheds, the Skeena and Nass, in north-western British Columbia, Canada. We synthesized life-history information derived from scales collected from adult steelhead (N = 7227) in these watersheds across a decade. These migratory fishes expressed 36 different manifestations of the anadromous life-history strategy, with 16 different combinations of freshwater and marine ages, 7·6% of fish performing multiple spawning migrations, and up to a maximum of four spawning migrations per lifetime. Furthermore, in the Nass watershed, various life histories were differently prevalent through time - three different life histories were the most prevalent in a given year, and no life history ever represented more than 45% of the population. These asynchronous dynamics among life histories decreased the variability of numerical abundance and biomass of the aggregated population so that it was > 20% more stable than the stability of the weighted average of specific life histories: evidence of a substantial portfolio effect. Year of ocean entry was a key driver of dynamics; the median correlation coefficient of abundance of life histories that entered the ocean the same year was 2·5 times higher than the median pairwise coefficient of life histories that entered the ocean at different times. Simulations illustrated how different elements of life-history diversity contribute to stability and persistence of populations. This study provides evidence that life-history diversity can dampen fluctuations in

Relation of parental history of coronary heart disease to obesity in young adults.

PubMed

Grotto, I; Huerta, M; Kark, J D; Shpilberg, O; Meyerovitch, J

2003-03-01

To assess the association between obesity and parental coronary heart disease (CHD) history. Analysis of data from an ongoing, large-scale survey on medical status, health behaviour and attitudes. Representative samples of Israeli military personnel upon discharge from compulsory service at age 20-22 y. Overall 14297 men and 11638 women were interviewed and examined upon release from military service between 1989 and 1999. Data on demographic characteristics, family history of CHD, lifestyle, weight and height were collected. Analysis of variance and logistic regression were used. Higher mean body mass index (BMI) and obesity (BMI>30 kg/m(2)) were associated with paternal CHD history in both sexes, and with maternal CHD history among men. Offspring of a parent with a positive CHD history had a higher mean BMI (23.22 vs 22.86 kg/m(2), P<0.001) and were more likely to be obese (5.4 vs 3.7%, P<0.001) than offspring of parents with no history of CHD. Multivariate adjustment for demographic and behavioural variables associated with obesity attenuated the association (adjusted odds ratio for obesity 1.37, 95% confidence interval: 1.15, 1.64). When stratified by sex, this association remained statistically significant only among males. Young adults with a parental history of CHD are more likely to be overweight. This high-risk group should be targeted for early preventive activities.

Toxic hydrogen sulphide and dark caves: pronounced male life-history divergence among locally adapted Poecilia mexicana (Poeciliidae).

PubMed

Riesch, R; Plath, M; Schlupp, I

2011-03-01

Chronic environmental stress is known to induce evolutionary change. Here, we assessed male life-history trait divergence in the neotropical fish Poecilia mexicana from a system that has been described to undergo incipient ecological speciation in adjacent, but reproductively isolated toxic/nontoxic and surface/cave habitats. Examining both field-caught and common garden-reared specimens, we investigated the extent of differentiation and plasticity of life-history strategies employed by male P. mexicana. We found strong site-specific life-history divergence in traits such as fat content, standard length and gonadosomatic index. The majority of site-specific life-history differences were also expressed under common garden-rearing conditions. We propose that apparent conservatism of male life histories is the result of other (genetically based) changes in physiology and behaviour between populations. Together with the results from previous studies, this is strong evidence for local adaptation as a result of ecologically based divergent selection. © 2010 The Authors. Journal of Evolutionary Biology © 2010 European Society For Evolutionary Biology.

Is continence status associated with quality of life in young children with spina bifida?

PubMed

Freeman, Kurt A; Smith, Kathryn; Adams, Elizabeth; Mizokawa, Stacey; Neville-Jan, Ann

2013-01-01

To evaluate the relationship between child- and parent-reported quality of life (QOL) and bowel and bladder continence among young children with spina bifida (SB). 104 children ages 5-12 years and one of their parents/guardians completed the Pediatric Quality of Life Inventory - Generic Form (PedsQL; parent and child) and the Quality of Life in Spina Bifida Questionnaire (QOLSBQ, parent only). Data on continence, child age, and condition-specific variables were obtained by chart review. Parent and child QOL scores (on all measures of QOL) were positively correlated; parents rated child QOL lower than children's self report. QOL scores did not differ based on continence status. Total PedsQL scores were associated with age and mobility based on child report and with mobility based on parent report. QOL may not be affected by continence status among young children with SB, though demographic (i.e., age) and condition-specific (i.e., functional mobility status) variables appear relevant. Additional research is needed to further evaluate condition-specific variables, other protective variables, and possible measurement issues that influence QOL in young children with SB.

In Search of Historical Consciousness: An Investigation into Young South Africans' Knowledge and Understanding of "Their" National Histories

ERIC Educational Resources Information Center

Angier, Kate

2017-01-01

This study reports the findings of an investigation into young South Africans' knowledge and understanding of their national past derived from narrative accounts of South African history written by 27 university students who had recently completed the national school history curriculum. Analysis of these narratives indicates two fundamental…

The Role of Perceived Stress and Self-Efficacy in Young People's Life Satisfaction: A Longitudinal Study.

PubMed

Burger, Kaspar; Samuel, Robin

2017-01-01

Life satisfaction is an important indicator of successful development. However, adolescents' life satisfaction tends to be relatively unsteady, and environmental influences play a critical role in shaping life satisfaction among adolescents in the transition to young adulthood. Given the paramount importance that education plays in adolescents' lives, adolescents' life satisfaction may vary as a function of school-related stress experience. At the same time, coping resources may help reduce adverse effects of stress on life satisfaction. With this in mind, we examined whether, and to what extent, perceived stress in education and general self-efficacy (a resource that facilitates coping) affect the life satisfaction of adolescents in transition to young adulthood. We distinguished between baseline levels of stress and self-efficacy and within-person change in stress and self-efficacy to determine whether life satisfaction is sensitive to fluctuations in stress and self-efficacy when person-specific levels of stress and self-efficacy are taken into account. Estimating growth curve models on data from a panel study on the life trajectories of compulsory-school leavers (n = 5126, 55.3 % female), we found that baseline levels of stress and self-efficacy, as well as within-person change in stress and self-efficacy, affected adolescents' life satisfaction. Moreover, our results showed that baseline self-efficacy mitigated the negative effect of baseline stress on life satisfaction. These findings improve our understanding of two major psychological determinants of adolescents' life satisfaction and extend our knowledge of life satisfaction trajectories during the transition to young adulthood.

Life-history strategies associated with local population variability confer regional stability.

PubMed

Pribil, Stanislav; Houlahan, Jeff E

2003-07-07

A widely held ecological tenet is that, at the local scale, populations of K-selected species (i.e. low fecundity, long lifespan and large body size) will be less variable than populations of r-selected species (i.e. high fecundity, short lifespan and small body size). We examined the relationship between long-term population trends and life-history attributes for 185 bird species in the Czech Republic and found that, at regional spatial scales and over moderate temporal scales (100-120 years), K-selected bird species were more likely to show both large increases and decreases in population size than r-selected species. We conclude that life-history attributes commonly associated with variable populations at the local scale, confer stability at the regional scale.

Demography, life history, and the evolution of age-dependent social behaviour.

PubMed

Rodrigues, António M M

2018-06-14

Since the inception of modern social evolution theory, a vast majority of studies have sought to explain cooperation using relatedness-driven hypotheses. Natural populations, however, show a substantial amount of variation in social behaviour that is uncorrelated with relatedness. Age offers a major alternative explanation for variation in behaviour that remains unaccounted for. Most natural populations are structured into age-classes, with ageing being a nearly universal feature of most major taxa, including eukaryotic and prokaryotic organisms. Despite this, the theoretical underpinnings of age-dependent social behaviour remain limited. Here, we investigate how group age-composition, demography, and life history shape trajectories of age-dependent behaviours that are expressed conditionally on an actor and recipient's age. We show that demography introduces novel age-dependent selective pressures acting on social phenotypes. Furthermore, we find that life history traits influence the costs and benefits of cooperation directly, but also indirectly. Life history has a strong impact not only on the genetic structure of the population but also on the distribution of group age-compositions, with both of these processes influencing the expression of age-dependent cooperation. Age of peak reproductive performance, in particular, is of chief importance for the evolution of cooperation, as this will largely determine the age and relatedness of social partners. Moreover, our results suggest that later-life reproductive senescence may occur because of demographic effects alone, which opens new vistas on the evolution of menopause and related phenomena. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

The Mass-Longevity Triangle: Pareto Optimality and the Geometry of Life-History Trait Space

PubMed Central

Szekely, Pablo; Korem, Yael; Moran, Uri; Mayo, Avi; Alon, Uri

2015-01-01

When organisms need to perform multiple tasks they face a fundamental tradeoff: no phenotype can be optimal at all tasks. This situation was recently analyzed using Pareto optimality, showing that tradeoffs between tasks lead to phenotypes distributed on low dimensional polygons in trait space. The vertices of these polygons are archetypes—phenotypes optimal at a single task. This theory was applied to examples from animal morphology and gene expression. Here we ask whether Pareto optimality theory can apply to life history traits, which include longevity, fecundity and mass. To comprehensively explore the geometry of life history trait space, we analyze a dataset of life history traits of 2105 endothermic species. We find that, to a first approximation, life history traits fall on a triangle in log-mass log-longevity space. The vertices of the triangle suggest three archetypal strategies, exemplified by bats, shrews and whales, with specialists near the vertices and generalists in the middle of the triangle. To a second approximation, the data lies in a tetrahedron, whose extra vertex above the mass-longevity triangle suggests a fourth strategy related to carnivory. Each animal species can thus be placed in a coordinate system according to its distance from the archetypes, which may be useful for genome-scale comparative studies of mammalian aging and other biological aspects. We further demonstrate that Pareto optimality can explain a range of previous studies which found animal and plant phenotypes which lie in triangles in trait space. This study demonstrates the applicability of multi-objective optimization principles to understand life history traits and to infer archetypal strategies that suggest why some mammalian species live much longer than others of similar mass. PMID:26465336

Extinction-effective population index: incorporating life-history variations in population viability analysis.

PubMed

Fujiwara, Masami

2007-09-01

Viability status of populations is a commonly used measure for decision-making in the management of populations. One of the challenges faced by managers is the need to consistently allocate management effort among populations. This allocation should in part be based on comparison of extinction risks among populations. Unfortunately, common criteria that use minimum viable population size or count-based population viability analysis (PVA) often do not provide results that are comparable among populations, primarily because they lack consistency in determining population size measures and threshold levels of population size (e.g., minimum viable population size and quasi-extinction threshold). Here I introduce a new index called the "extinction-effective population index," which accounts for differential effects of demographic stochasticity among organisms with different life-history strategies and among individuals in different life stages. This index is expected to become a new way of determining minimum viable population size criteria and also complement the count-based PVA. The index accounts for the difference in life-history strategies of organisms, which are modeled using matrix population models. The extinction-effective population index, sensitivity, and elasticity are demonstrated in three species of Pacific salmonids. The interpretation of the index is also provided by comparing them with existing demographic indices. Finally, a measure of life-history-specific effect of demographic stochasticity is derived.

Herbivore-mediated ecological costs of reproduction shape the life history of an iteroparous plant.

PubMed

Miller, Tom E X; Tenhumberg, Brigitte; Louda, Svata M

2008-02-01

Plant reproduction yields immediate fitness benefits but can be costly in terms of survival, growth, and future fecundity. Life-history theory posits that reproductive strategies are shaped by trade-offs between current and future fitness that result from these direct costs of reproduction. Plant reproduction may also incur indirect ecological costs if it increases susceptibility to herbivores. Yet ecological costs of reproduction have received little empirical attention and remain poorly integrated into life-history theory. Here, we provide evidence for herbivore-mediated ecological costs of reproduction, and we develop theory to examine how these costs influence plant life-history strategies. Field experiments with an iteroparous cactus (Opuntia imbricata) indicated that greater reproductive effort (proportion of meristems allocated to reproduction) led to greater attack by a cactus-feeding insect (Narnia pallidicornis) and that damage by this herbivore reduced reproductive success. A dynamic programming model predicted strongly divergent optimal reproductive strategies when ecological costs were included, compared with when these costs were ignored. Meristem allocation by cacti in the field matched the optimal strategy expected under ecological costs of reproduction. The results indicate that plant reproductive allocation can strongly influence the intensity of interactions with herbivores and that associated ecological costs can play an important selective role in the evolution of plant life histories.

Life history trade-offs and relaxed selection can decrease bacterial virulence in environmental reservoirs.

PubMed

Mikonranta, Lauri; Friman, Ville-Petri; Laakso, Jouni

2012-01-01

Pathogen virulence is usually thought to evolve in reciprocal selection with the host. While this might be true for obligate pathogens, the life histories of opportunistic pathogens typically alternate between within-host and outside-host environments during the infection-transmission cycle. As a result, opportunistic pathogens are likely to experience conflicting selection pressures across different environments, and this could affect their virulence through life-history trait correlations. We studied these correlations experimentally by exposing an opportunistic bacterial pathogen Serratia marcescens to its natural protist predator Tetrahymena thermophila for 13 weeks, after which we measured changes in bacterial traits related to both anti-predator defence and virulence. We found that anti-predator adaptation (producing predator-resistant biofilm) caused a correlative attenuation in virulence. Even though the direct mechanism was not found, reduction in virulence was most clearly connected to a predator-driven loss of a red bacterial pigment, prodigiosin. Moreover, life-history trait evolution was more divergent among replicate populations in the absence of predation, leading also to lowered virulence in some of the 'predator absent' selection lines. Together these findings suggest that the virulence of non-obligatory, opportunistic bacterial pathogens can decrease in environmental reservoirs through life history trade-offs, or random accumulation of mutations that impair virulence traits under relaxed selection.

A Spurious Correlation in an Interpopulation Comparison of Atlantic Salmon Life Histories.

PubMed

Myers, Ransom A; Hutchings, Jeffrey A

1987-12-01

We tested two hypotheses concerning geographical variation in Atlantic salmon (Salmo salar) life histories: (1) mean age at first reproduction is positively correlated with growth rate at sea and (2) within-population variation in age at first reproduction first increases and then decreases with latitude. Data on growth and age at first reproduction were compiled from 41 populations in eastern North America. Data reliability was checked by a redetermination of ages based on scale examination. The proportion of fish that were incorrectly aged was small (°0.7%); however, aging errors were primarily of one kind; salmon that had previously spawned were misclassified as virgin fish of an older age class. Growth rate at sea was found not to be positively correlated with age at maturation. Schaffer and Elson's (1975) positive correlation between growth and age at first reproduction can be attributed to a subtle statistical artifact caused by aging errors. We also found that within-population variation of age at maturation was not related to latitude. We conclude that tests of life history theories should not assume constancy in life history traits, such as mortality, among populations. © 1987 by the Ecological Society of America.

Partitioning the non‑consumptive effects of predators on preywith complex life histories

USGS Publications Warehouse

Davenport, Jon M.; Hossack, Blake R.; Lowe, Winsor H.

2014-01-01

Non-consumptive effects (NCEs) of predators on prey can be as strong as consumptive effects (CEs) and may be driven by numerous mechanisms, including predator characteristics. Previous work has highlighted the importance of predator characteristics in predicting NCEs, but has not addressed how complex life histories of prey could mediate predator NCEs. We conducted a meta-analysis to compare the effects of predator gape limitation (gape limited or not) and hunting mode (active or sit-and-pursue) on the activity, larval period, and size at metamorphosis of larval aquatic amphibians and invertebrates. Larval prey tended to reduce their activity and require more time to reach metamorphosis in the presence of all predator functional groups, but the responses did not differ from zero. Prey metamorphosed at smaller size in response to non-gape-limited, active predators, but counter to expectations, prey metamorphosed larger when confronted by non-gape-limited, sit-and-pursue predators. These results indicate NCEs on larval prey life history can be strongly influenced by predator functional characteristics. More broadly, our results suggest that understanding predator NCEs would benefit from greater consideration of how prey life history attributes mediate population and community-level outcomes.

Comparing life history characteristics of Lake Michigan’s naturalized and stocked Chinook Salmon

USGS Publications Warehouse

Kerns, Janice A; Rogers, Mark W.; Bunnell, David B.; Claramunt, Randall M.; Collingsworth, Paris D.

2016-01-01

Lake Michigan supports popular fisheries for Chinook Salmon Oncorhynchus tshawytscha that have been sustained by stocking since the late 1960s. Natural recruitment of Chinook Salmon in Lake Michigan has increased in the past few decades and currently contributes more than 50% of Chinook Salmon recruits. We hypothesized that selective forces differ for naturalized populations born in the wild and hatchery populations, resulting in divergent life history characteristics with implications for Chinook Salmon population production and the Lake Michigan fishery. First, we conducted a historical analysis to determine if life history characteristics changed through time as the Chinook Salmon population became increasingly naturalized. Next, we conducted a 2-year field study of naturalized and hatchery stocked Chinook Salmon spawning populations to quantify differences in fecundity, egg size, timing of spawning, and size at maturity. In general, our results did not indicate significant life history divergence between naturalized and hatchery-stocked Chinook Salmon populations in Lake Michigan. Although historical changes in adult sex ratio were correlated with the proportion of naturalized individuals, changes in weight at maturity were better explained by density-dependent factors. The field study revealed no divergence in fecundity, timing of spawning, or size at maturity, and only small differences in egg size (hatchery > naturalized). For the near future, our results suggest that the limited life history differences observed between Chinook Salmon of naturalized and hatchery origin will not lead to large differences in characteristics important to the dynamics of the population or fishery.

A review of Ruffe (Gymnocephalus cernuus) life history in its ...

EPA Pesticide Factsheets

Ruffe (Gymnocephalus cernuus) have caused and have the potential to cause great ecological damage as invasive species in North America, parts of the European Union, Scandinavian countries, and the United Kingdom. The objectives of this review are to define the Ruffe's native and non-native range, examine the life history requirements of Ruffe, explore the Ruffe life cycle, and differentiate between the life stages. We compare Ruffe in their native range to Ruffe in their non-native range to determine if there are any differences in habitat, size, age, genotype, or migratory patterns in the winter. Literature from both the native and non-native ranges of Ruffe, with a particular emphasis on rare translated literature, is used. Ruffe have variability and plasticity in their chemical, physical, biological, and habitat requirements in their native and non-native ranges. Adult Ruffe have a suite of characteristics that make them adaptable to novel environments, including age and size at maturity, maximum age and length (and/ or weight), reproduction type, genotype, feeding habits, seasonal movements, and spawning movements. There is variability among these characteristics seen between the Ruffe's native, non-native North American, and European non-native populations. Based on the Ruffe's variable life history strategies and their recent range expansion, all of the Great Lakes and many other regions in the U.K., Europe, and Scandinavian countries could be vulnerable t

Extreme plasticity in life-history strategy allows a migratory predator (jumbo squid) to cope with a changing climate.

PubMed

Hoving, Henk-Jan T; Gilly, William F; Markaida, Unai; Benoit-Bird, Kelly J; -Brown, Zachary W; Daniel, Patrick; Field, John C; Parassenti, Liz; Liu, Bilin; Campos, Bernardita

2013-07-01

Dosidicus gigas (jumbo or Humboldt squid) is a semelparous, major predator of the eastern Pacific that is ecologically and commercially important. In the Gulf of California, these animals mature at large size (>55 cm mantle length) in 1-1.5 years and have supported a major commercial fishery in the Guaymas Basin during the last 20 years. An El Niño event in 2009-2010, was accompanied by a collapse of this fishery, and squid in the region showed major changes in the distribution and life-history strategy. Large squid abandoned seasonal coastal-shelf habitats in 2010 and instead were found in the Salsipuedes Basin to the north, an area buffered from the effects of El Niño by tidal upwelling and a well-mixed water column. The commercial fishery also relocated to this region. Although large squid were not found in the Guaymas Basin from 2010 to 2012, small squid were abundant and matured at an unusually small mantle-length (<30 cm) and young age (approximately 6 months). Juvenile squid thus appeared to respond to El Niño with an alternative life-history trajectory in which gigantism and high fecundity in normally productive coastal-shelf habitats were traded for accelerated reproduction at small size in an offshore environment. Both small and large mature squid, were present in the Salsipuedes Basin during 2011, indicating that both life- history strategies can coexist. Hydro-acoustic data, reveal that squid biomass in this study area nearly doubled between 2010 and 2011, primarily due to a large increase in small squid that were not susceptible to the fishery. Such a climate-driven switch in size-at-maturity may allow D. gigas to rapidly adapt to and cope with El Niño. This ability is likely to be an important factor in conjunction with longerterm climate-change and the potential ecological impacts of this invasive predator on marine ecosystems. © 2013 Blackwell Publishing Ltd.

Ecology, Life History, and Management of Tropilaelaps Mites.

PubMed

de Guzman, Lilia I; Williams, Geoffrey R; Khongphinitbunjong, Kitiphong; Chantawannakul, Panuwan

2017-04-01

Parasitic mites are the major threat to the Western honey bee, Apis mellifera L. For much of the world, Varroa destructor Anderson & Trueman single-handedly inflicts unsurmountable problems to A. mellifera beekeeping. However, A. mellifera in Asia is also faced with another genus of destructive parasitic mite, Tropilaelaps. The life history of these two parasitic mites is very similar, and both have the same food requirements (i.e., hemolymph of developing brood). Hence, parasitism by Tropilaelaps spp., especially Tropilaelaps mercedesae and Tropilaelaps clareae, also results in death of immature brood or wing deformities in infested adult bees. The possible introduction of Tropilaelaps mites outside their current range heightens existing dilemmas brought by Varroa mites. In this review, we provide historic, as well as current information on the taxonomic status, life history, distribution and host range, diagnosis, and control of Tropilaelaps mites. Because the biology of Tropilaelaps mites is not well known, we also suggest areas of research that demand immediate attention. Any biological information about Tropilaelaps mites will provide useful information for the development of control measures against them. Published by Oxford University Press on behalf of Entomological Society of America 2017. This work is written by US Government employees and is in the public domain in the US.

The impact of acne vulgaris on quality of life and psychic health in young adolescents in Greece. Results of a population survey*

PubMed Central

Tasoula, Eleni; Gregoriou, Stamatis; Chalikias, John; Lazarou, Dimitris; Danopoulou, Ifigenia; Katsambas, Andreas; Rigopoulos, Dimitris

2012-01-01

BACKGROUND Acne vulgaris can severely affect social and psychological functioning. OBJECTIVE The aim of this study was to investigate the impact of acne vulgaris and its severity on Quality of Life of young adolescents in Greece. METHODS We conducted a questionnaire based survey among 1560 adolescent between the ages of 11 and 19 years old and 1531 of these were completed. Adolescents with acne filled all the questions including the Children Dermatology Life Quality Index. Adolescents without acne filled the questions about age, family history of acne, stress and smoking. Data were analyzed with Pearson Chi Square test. RESULTS Acne prevalence was 51.2% affecting both sexes equally. Self reported mild acne was present in 71.2% and moderate-severe acne in 28.8% of the study population. The mean age of the study population was 15.77y. The median score of Children Dermatology Life Quality Index was 4.02. The impact of acne on quality of life is associated with the severity of the acne (p<0.0001). Patients with moderate/severe acne experience greater psychosocial and emotional impairment (p<0.0001). Body image is modified proportionally to the severity of acne (p<0.0001). Symptoms and treatment of acne are factors that also influence their quality of life. Girls and boys are equally affected. Stress and heredity are correlated with acne and its severity (p<0.0001). We didn't find any correlation between smoking and acne. CONCLUSION Acne affects Quality of Life of young adolescents in Greece. The impact is proportional to the severity of acne. More severe acne is associated with greater effect on quality of life with implications for self esteem, body image and relationships with others. PMID:23197205

Physical maturation, life-history classes and age estimates of free-ranging western gorillas--insights from Mbeli Bai, Republic of Congo.

PubMed

Breuer, Thomas; Hockemba, Mireille Breuer-Ndoundou; Olejniczak, Claudia; Parnell, Richard J; Stokes, Emma J

2009-02-01

Physical maturation and life-history parameters are seen as evolutionary adaptations to different ecological and social conditions. Comparison of life-history patterns of closely related species living in diverse environments helps to evaluate the validity of these assumptions but empirical data are lacking. The two gorilla species exhibit substantial differences in their environment, which allows investigation into the role of increased frugivory in shaping western gorilla life histories. We present behavioral and morphological data on western gorilla physical maturation and life-history parameters from a 12.5-year study at Mbeli Bai, a forest clearing in the Nouabalé-Ndoki National Park in northern Congo. We assign photographs of known individuals to different life-history classes and propose new age boundaries for life-history classes in western gorillas, which can be used and tested at other western gorilla research sites. Our results show that western gorillas are weaned at a later age compared with mountain gorillas and indicate slower physical maturation of immatures. These findings support the risk-aversion hypothesis for more frugivorous species. However, our methods need to be applied and tested with other gorilla populations. The slow life histories of western gorillas could have major consequences for social structure, mortality patterns and population growth rates that will affect recovery from population crashes of this critically endangered species. We emphasize that long-term studies can provide crucial demographic and life-history data that improve our understanding of life-history evolution and adaptation and help to refine conservation strategies. (c) 2008 Wiley-Liss, Inc.

Difficulties in everyday life: young persons with attention-deficit/hyperactivity disorder and autism spectrum disorders perspectives. A chat-log analysis.

PubMed

Ahlström, Britt H; Wentz, Elisabet

2014-01-01

This study focuses on the everyday life of young persons with attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). There are follow-up studies describing ADHD, and ASD in adults, and residual impairments that affect life. Few qualitative studies have been conducted on the subject of their experiences of everyday life, and even fewer are from young persons' perspectives. This study's aim was to describe how young persons with ADHD and ASD function and how they manage their everyday life based on analyses of Internet-based chat logs. Twelve young persons (7 males and 5 females aged 15-26) diagnosed with ADHD and ASD were included consecutively and offered 8 weeks of Internet-based Support and Coaching (IBSC). Data were collected from 12 chat logs (445 pages of text) produced interactively by the participants and the coaches. Qualitative content analysis was applied. The text was coded and sorted into subthemes and further interpreted into themes. The findings revealed two themes: "fighting against an everyday life lived in vulnerability" with the following subthemes: "difficult things," "stress and rest," and "when feelings and thoughts are a concern"; and the theme "struggling to find a life of one's own" with the following subthemes: "decide and carry out," "making life choices," and "taking care of oneself." Dealing with the problematic situations that everyday encompasses requires personal strength and a desire to find adequate solutions, as well as to discover a role in society. This study, into the provision of support and coaching over the Internet, led to more in-depth knowledge about these young persons' everyday lives and revealed their ability to use IBSC to express the complexity of everyday life for young persons with ADHD and ASD. The implications of the findings are that using online coaching makes available new opportunities for healthcare professionals to acknowledge these young persons' problems.

From metamorphosis to maturity in complex life cycles: equal performance of different juvenile life history pathways.

PubMed

Schmidt, Benedikt R; Hödl, Walter; Schaub, Michael

2012-03-01

Performance in one stage of a complex life cycle may affect performance in the subsequent stage. Animals that start a new stage at a smaller size than conspecifics may either always remain smaller or they may be able to "catch up" through plasticity, usually elevated growth rates. We study how size at and date of metamorphosis affected subsequent performance in the terrestrial juvenile stage and lifetime fitness of spadefoot toads (Pelobates fuscus). We analyzed capture-recapture data of > 3000 individuals sampled during nine years with mark-recapture models to estimate first-year juvenile survival probabilities and age-specific first-time breeding probabilities of toads, followed by model selection to assess whether these probabilities were correlated with size at and date of metamorphosis. Males attained maturity after two years, whereas females reached maturity 2-4 years after metamorphosis. Age at maturity was weakly correlated with metamorphic traits. In both sexes, first-year juvenile survival depended positively on date of metamorphosis and, in males, also negatively on size at metamorphosis. In males, toads that metamorphosed early at a small size had the highest probability to reach maturity. However, because very few toadlets metamorphosed early, the vast majority of male metamorphs had a very similar probability to reach maturity. A matrix projection model constructed for females showed that different juvenile life history pathways resulted in similar lifetime fitness. We found that the effects of date of and size at metamorphosis on different juvenile traits cancelled each other out such that toads that were small or large at metamorphosis had equal performance. Because the costs and benefits of juvenile life history pathways may also depend on population fluctuations, ample phenotypic variation in life history traits may be maintained.

Muscogee Nation Indian Territory: From Oral History to Found Poetry

ERIC Educational Resources Information Center

Treat, James

2017-01-01

The Indian-Pioneer History Project began in the spring of 1937, when scores of young field workers set out to interview elderly Oklahomans who could recall life during territorial days. Funded by the federal government's Works Progress Administration and sponsored by the Oklahoma Historical Society (OHS) in cooperation with the University of…

A Perspective on Quercus Life History Characteristics and Forest Diturbance

Treesearch

Richard P. Guyette; Rose-Marie Muzika; John Kabrick; Michael C. Stambaugh

2004-01-01

Plant strategy theory suggests that life history characteristics reflect growth and reproductive adaptations to environmental disturbance. Species characteristics and abundance should correspond to predictions based on competitive ability and maximizing fitness in a given disturbance environment. A significant canonical correlation between oak growth attributes (height...

Contributions of dynamic environmental signals during life-cycle transitions to early life-history traits in lodgepole pine (Pinus contorta Dougl.)

NASA Astrophysics Data System (ADS)

Liu, Yang; Wang, Tongli; El-Kassaby, Yousry A.

2016-05-01

Environmental signals are important triggers in the life-cycle transitions and play a crucial role in the life-history evolution. Yet very little is known about the leading ecological factors contributing to the variations of life-history traits in perennial plants. This paper explores both the causes and consequences for the evolution of life-history traits (i.e., seed dormancy and size) in lodgepole pine (Pinus contorta Dougl.) across British Columbia (B.C.), Canada. We selected 83 logepole pine populations covering 22 ecosystem zones of B.C. and through their geographic coordinate, 197 climatic variables were generated accordingly for the reference (1961-1990) and future (2041-2070) periods. We found that dynamic climatic variables rather than constant geographic variables are the true environmental driving forces in seed dormancy and size variations and thus provide reliable predictors in response to global climate change. Evapotranspiration and precipitation in the plant-to-seed chronology are the most critical climate variables for seed dormancy and size variations, respectively. Hence, we predicted that levels of seed dormancy in lodgepole pine would increase across large tracts of B.C. in 2050s. Winter-chilling is able to increase the magnitude of life-history plasticity and lower the bet-hedge strategy in the seed-to-plant transition; however, winter-chilling is likely to be insufficient in the north of 49° N in 2050s, which may delay germination while unfavorable conditions during dry summers may result in adverse consequences in the survival of seedlings owing to extended germination span. These findings provide useful information to studies related to assessments of seed transfer and tree adaptation.

Love, Sex, and Personality Pathology: A Life History View of Personality Pathologies and Sociosexuality.

PubMed

Jonason, Peter K; Zeigler-Hill, Virgil; Hashmani, Talia

2018-05-24

Love and sex are fundamental needs of most people, yet little research has examined such aspects of life in relation to personality pathologies. We examined the associations between pathological personality traits (i.e., negative affectivity, disinhibition, antagonism, psychoticism, and detachment) and sociosexuality (i.e., short-term mating orientation, long-term mating orientation, and sexual behavior) among 702 university students. In addition, we examined the mediating role of life history speed and tested whether sex moderated the associations that these pathological personality traits had with sociosexuality. Detachment, antagonism, disinhibition, and psychoticism had positive associations with short-term mating interests and negative associations with long-term mating interests. Life history speed mediated the associations that detachment and disinhibition had with short-term mating orientation and long-term mating orientation. Although sex did moderate the association that negative affectivity had with previous sexual behavior, we found no evidence that these mediational processes differed between men and women. Results are discussed in terms of the way personality traits shape the sociosexuality of men and women using a life history paradigm.

Climatic and geographic predictors of life history variation in Eastern Massasauga (Sistrurus catenatus): A range-wide synthesis.

PubMed

Hileman, Eric T; King, Richard B; Adamski, John M; Anton, Thomas G; Bailey, Robyn L; Baker, Sarah J; Bieser, Nickolas D; Bell, Thomas A; Bissell, Kristin M; Bradke, Danielle R; Campa, Henry; Casper, Gary S; Cedar, Karen; Cross, Matthew D; DeGregorio, Brett A; Dreslik, Michael J; Faust, Lisa J; Harvey, Daniel S; Hay, Robert W; Jellen, Benjamin C; Johnson, Brent D; Johnson, Glenn; Kiel, Brooke D; Kingsbury, Bruce A; Kowalski, Matthew J; Lee, Yu Man; Lentini, Andrew M; Marshall, John C; Mauger, David; Moore, Jennifer A; Paloski, Rori A; Phillips, Christopher A; Pratt, Paul D; Preney, Thomas; Prior, Kent A; Promaine, Andrew; Redmer, Michael; Reinert, Howard K; Rouse, Jeremy D; Shoemaker, Kevin T; Sutton, Scott; VanDeWalle, Terry J; Weatherhead, Patrick J; Wynn, Doug; Yagi, Anne

2017-01-01

Elucidating how life history traits vary geographically is important to understanding variation in population dynamics. Because many aspects of ectotherm life history are climate-dependent, geographic variation in climate is expected to have a large impact on population dynamics through effects on annual survival, body size, growth rate, age at first reproduction, size-fecundity relationship, and reproductive frequency. The Eastern Massasauga (Sistrurus catenatus) is a small, imperiled North American rattlesnake with a distribution centered on the Great Lakes region, where lake effects strongly influence local conditions. To address Eastern Massasauga life history data gaps, we compiled data from 47 study sites representing 38 counties across the range. We used multimodel inference and general linear models with geographic coordinates and annual climate normals as explanatory variables to clarify patterns of variation in life history traits. We found strong evidence for geographic variation in six of nine life history variables. Adult female snout-vent length and neonate mass increased with increasing mean annual precipitation. Litter size decreased with increasing mean temperature, and the size-fecundity relationship and growth prior to first hibernation both increased with increasing latitude. The proportion of gravid females also increased with increasing latitude, but this relationship may be the result of geographically varying detection bias. Our results provide insights into ectotherm life history variation and fill critical data gaps, which will inform Eastern Massasauga conservation efforts by improving biological realism for models of population viability and climate change.

Climatic and geographic predictors of life history variation in Eastern Massasauga (Sistrurus catenatus): A range-wide synthesis

PubMed Central

King, Richard B.; Adamski, John M.; Anton, Thomas G.; Bailey, Robyn L.; Baker, Sarah J.; Bieser, Nickolas D.; Bell, Thomas A.; Bissell, Kristin M.; Bradke, Danielle R.; Campa, Henry; Casper, Gary S.; Cedar, Karen; Cross, Matthew D.; DeGregorio, Brett A.; Dreslik, Michael J.; Faust, Lisa J.; Harvey, Daniel S.; Hay, Robert W.; Jellen, Benjamin C.; Johnson, Brent D.; Johnson, Glenn; Kiel, Brooke D.; Kingsbury, Bruce A.; Kowalski, Matthew J.; Lee, Yu Man; Lentini, Andrew M.; Marshall, John C.; Mauger, David; Moore, Jennifer A.; Paloski, Rori A.; Phillips, Christopher A.; Pratt, Paul D.; Preney, Thomas; Prior, Kent A.; Promaine, Andrew; Redmer, Michael; Reinert, Howard K.; Rouse, Jeremy D.; Shoemaker, Kevin T.; Sutton, Scott; VanDeWalle, Terry J.; Weatherhead, Patrick J.; Wynn, Doug; Yagi, Anne

2017-01-01

Elucidating how life history traits vary geographically is important to understanding variation in population dynamics. Because many aspects of ectotherm life history are climate-dependent, geographic variation in climate is expected to have a large impact on population dynamics through effects on annual survival, body size, growth rate, age at first reproduction, size–fecundity relationship, and reproductive frequency. The Eastern Massasauga (Sistrurus catenatus) is a small, imperiled North American rattlesnake with a distribution centered on the Great Lakes region, where lake effects strongly influence local conditions. To address Eastern Massasauga life history data gaps, we compiled data from 47 study sites representing 38 counties across the range. We used multimodel inference and general linear models with geographic coordinates and annual climate normals as explanatory variables to clarify patterns of variation in life history traits. We found strong evidence for geographic variation in six of nine life history variables. Adult female snout-vent length and neonate mass increased with increasing mean annual precipitation. Litter size decreased with increasing mean temperature, and the size–fecundity relationship and growth prior to first hibernation both increased with increasing latitude. The proportion of gravid females also increased with increasing latitude, but this relationship may be the result of geographically varying detection bias. Our results provide insights into ectotherm life history variation and fill critical data gaps, which will inform Eastern Massasauga conservation efforts by improving biological realism for models of population viability and climate change. PMID:28196149

Fracture history in osteoporosis: risk factors and its effect on quality of life.

PubMed

Kuru, Pınar; Akyüz, Gülseren; Cerşit, Hülya Peynirci; Çelenlioğlu, Alp Eren; Cumhur, Ahmet; Biricik, Şefikcan; Kozan, Seda; Gökşen, Aylin; Özdemir, Mikail; Lüleci, Emel

2014-12-01

Fractures are one of the main outcomes in osteoporosis and have an important effect on the general health status. The purpose of this study was to determine the effect of major fracture history on quality of life. We also investigated the important risk factors and their effect on bone mineral density and fracture history. Cross-sectional study. We recruited 105 patients who were admitted to an osteoporosis outpatient clinic. Medical history, family history, calcium intake, physical activity level and biochemical tests were evaluated. Lumbar spine and femur neck bone mineral density were measured. The Qualeffo-41 questionnaire was also used for evaluating quality of life. The average age of the 105 patients included in the study was 56.04±13.73 and 89% of them were post-menopausal women. The average body mass index was 26.84±5.99, which means that the women were overweight. Also, 48.5% of the patients were diagnosed with osteoporosis and 51.5% of them were diagnosed as low bone density. A total of 34 patients had a fracture history with minor trauma and some of the patients had more than one fracture (12 ankle and foot, 10 forearm, 9 vertebral, 4 hand, 3 hip, 2 rib, 1 tibial). When the patients with and without fracture history were compared, the mean Qualeffo-41 score in patients with fracture was 43.85±2.57 and in the non-fracture group was 36.27±2.01. Forearm, ankle and foot fractures can be commonly seen in osteoporosis patients with fracture history. We suggest that it is important to recognise osteoporosis prior to first fracture and disease-specific quality of life assessment should be done.

Life satisfaction and happiness among young adults with schizophrenia.

PubMed

Fervaha, Gagan; Agid, Ofer; Takeuchi, Hiroyoshi; Foussias, George; Remington, Gary

2016-08-30

People with schizophrenia often experience persistent symptoms and impairments in community functioning; however, despite this, many individuals with the illness report high levels of well-being. We explored the level of subjective well-being in a sample of relatively young outpatients with schizophrenia and matched healthy controls. Seventy-five outpatients with schizophrenia and 72 demographically matched healthy controls, aged 18-35 years, participated in the present study. Subjective well-being was defined as a combination of happiness and satisfaction with life, each of which were measured using validated instruments. Symptom severity, insight, and cognition were also evaluated. People with schizophrenia endorsed significantly lower levels of subjective well-being than healthy controls although, there was substantial overlap in scores, and many participants with schizophrenia endorsed a high level of well-being. Both depressive symptoms and motivational deficits demonstrated significant independent predictive value for determining level of well-being. At a group level, the mean level of happiness and life satisfaction was lower among people with schizophrenia than healthy comparison participants. However, despite this mean difference, there exists marked overlap in individual scores between those with and without schizophrenia, demonstrating that many young people with schizophrenia do, in fact, endorse high levels of subjective well-being. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

History + Mystery = Inquiring Young Historians

ERIC Educational Resources Information Center

Kirchner, Jana; Helm, Allison; Pierce, Kristin; Galloway, Michele

2011-01-01

While social studies content about communities, neighborhood jobs, and maybe even some state history is taught in the early elementary grades, often the upper elementary grades are the first time students learn about the larger progression of history. How do teachers begin to teach the progression of U.S. history and the themes and questions that…

Modelling the sensitivity of life history traits to climate change in a temporary pool crustacean.

PubMed

Pinceel, Tom; Vanschoenwinkel, Bram; Brendonck, Luc; Buschke, Falko

2016-07-11

Temporary pool inhabitants face altered inundation regimes under climate change. While their exposure to these changes has received considerable attention, few studies have investigated their sensitivity or adaptability. Here, we use zooplankton as a model to explore how decreasing hydroperiods affect extinction risks and assess whether changes in life history traits could promote persistence. For this, we construct a three-stage matrix population model parameterised with realistic life-history values for the fairy shrimp Branchipodopsis wolfi from pools with varying hydroperiods. Our results suggest that extinction risks increase drastically once the median hydroperiod drops below a critical threshold. Although changes in life-history parameters could potentially compensate for this risk, the relative importance of each trait for population growth depends on the median hydroperiod. For example, survival of dormant eggs seemed to be most important when hydroperiods were short while the survival of freshly laid eggs and adult individuals were more important in longer-lived pools. Overall, this study demonstrates that zooplankton species are sensitive to climate change and that the adaptive capacity of organisms from temporary pools with dissimilar hydrology hinges on selection of different life history traits.

[TRANSFORMATIONS OF LIFE CYCLES IN THE EVOLUTIONARY HISTORY OF TRYPANOSOMATIDAE. EXOTRANSFORMATIONS].

PubMed

Frolov, A O; Malysheva, M N; Kostygov, A Yu

2015-01-01

The present review is devoted to the analysis of exotransformations of life cycles in the evolutionary history of trypanosomatids (Kinetoplastea: Trypanosomatidae). Exotransformations are treated as processes associated with the transition of a trypanosomatid to a new host. The result of these transformations comprises both the inclusion of new hosts in life cycles of parasites and also epy formation of parasitic systems de novo. It is shown that exotransformations are one of the main modi in the evolution of trypanosomatids. Different examples of exotransformations of life cycle in all the taxonomic groups of Trypanosomatidae are given.

[TRANSFORMATIONS OF LIFE CYCLES IN THE EVOLUTIONARY HISTORY OF TRYPANOSOMATIDS. MACROTRANSFORMATIONS].

PubMed

Frolov, A O; Malysheva, M N; Kostygov, A Yu

2015-01-01

The review concerns analysis of life cycle macrotransformations in the evolutionary history of trypanosomatids. The term "macrotransformations" stands for evolutionary processes leading to the establishment of heteroxenous and secondary homoxenous life cycles within Trypanosomatidae. There were three direct macrotransformations in the evolution of the group resulting in the rise of heteroxenous genera Leishmania, Trypanosoma and Phytomonas, and one case of reverse macrotransformation in trypanosomes of T. (b.) brucei group. The issues of the origin, diversity and phylogeny of taxa whose emergence resulted from macrotransformations of life cycles of homoxenous trypanosomatids.

Breathing Life into History: Using Role-Playing to Engage Students

ERIC Educational Resources Information Center

Cruz, Barbara C.; Murthy, Shalini A.

2006-01-01

Alternately referred to as historical role-playing, dramatic improvisation, sociodrama, or first-person characterization, role playing is a teaching strategy that often uses official accounts, personal narratives, and diaries to recreate a particular time period, specific event, or breathe life into a character from history. Historical…

Switch between life history strategies due to changes in glycolytic enzyme gene dosage in Saccharomyces cerevisiae.

PubMed

Wang, Shaoxiao; Spor, Aymé; Nidelet, Thibault; Montalent, Pierre; Dillmann, Christine; de Vienne, Dominique; Sicard, Delphine

2011-01-01

Adaptation is the process whereby a population or species becomes better fitted to its habitat through modifications of various life history traits which can be positively or negatively correlated. The molecular factors underlying these covariations remain to be elucidated. Using Saccharomyces cerevisiae as a model system, we have investigated the effects on life history traits of varying the dosage of genes involved in the transformation of resources into energy. Changing gene dosage for each of three glycolytic enzyme genes (hexokinase 2, phosphoglucose isomerase, and fructose-1,6-bisphosphate aldolase) resulted in variation in enzyme activities, glucose consumption rate, and life history traits (growth rate, carrying capacity, and cell size). However, the range of effects depended on which enzyme was expressed differently. Most interestingly, these changes revealed a genetic trade-off between carrying capacity and cell size, supporting the discovery of two extreme life history strategies already described in yeast populations: the "ants," which have lower glycolytic gene dosage, take up glucose slowly, and have a small cell size but reach a high carrying capacity, and the "grasshoppers," which have higher glycolytic gene dosage, consume glucose more rapidly, and allocate it to a larger cell size but reach a lower carrying capacity. These results demonstrate antagonist pleiotropy for glycolytic genes and show that altered dosage of a single gene drives a switch between two life history strategies in yeast.

Deciphering the adjustment between environment and life history in annuals: lessons from a geographically-explicit approach in Arabidopsis thaliana.

PubMed

Manzano-Piedras, Esperanza; Marcer, Arnald; Alonso-Blanco, Carlos; Picó, F Xavier

2014-01-01

The role that different life-history traits may have in the process of adaptation caused by divergent selection can be assessed by using extensive collections of geographically-explicit populations. This is because adaptive phenotypic variation shifts gradually across space as a result of the geographic patterns of variation in environmental selective pressures. Hence, large-scale experiments are needed to identify relevant adaptive life-history traits as well as their relationships with putative selective agents. We conducted a field experiment with 279 geo-referenced accessions of the annual plant Arabidopsis thaliana collected across a native region of its distribution range, the Iberian Peninsula. We quantified variation in life-history traits throughout the entire life cycle. We built a geographic information system to generate an environmental data set encompassing climate, vegetation and soil data. We analysed the spatial autocorrelation patterns of environmental variables and life-history traits, as well as the relationship between environmental and phenotypic data. Almost all environmental variables were significantly spatially autocorrelated. By contrast, only two life-history traits, seed weight and flowering time, exhibited significant spatial autocorrelation. Flowering time, and to a lower extent seed weight, were the life-history traits with the highest significant correlation coefficients with environmental factors, in particular with annual mean temperature. In general, individual fitness was higher for accessions with more vigorous seed germination, higher recruitment and later flowering times. Variation in flowering time mediated by temperature appears to be the main life-history trait by which A. thaliana adjusts its life history to the varying Iberian environmental conditions. The use of extensive geographically-explicit data sets obtained from field experiments represents a powerful approach to unravel adaptive patterns of variation. In a

Relationship between a history of consistent maternal employment and depression in young adults.

PubMed

Chambliss, Catherine; Termine, Kim; Norton, Jenifer; Barry, Oliver; Bahm, Jonathan; Papas, Adam; Papas, Harris

2010-12-01

Research on the correlates of maternal employment has yielded inconsistent results. In this study, 79 male and 120 female undergraduates with mothers who had been employed from the students' infancy through their adolescence scored higher on the Beck Depression Inventory-II than those whose mothers had not been employed. This relationship between children's depressive symptoms and mothers' employment history was not evident among young adults whose mothers' employment was perceived to be financially unnecessary.

Life-history variation and allometry for sexual size dimorphism in Pacific salmon and trout

PubMed Central

Young, Kyle A.

2005-01-01

Allometry for sexual size dimorphism (SSD) is common in animals, but how different evolutionary processes interact to determine allometry remains unclear. Among related species SSD (male:female) typically increases with average body size, resulting in slopes of less than 1 when female size is regressed on male size: an allometric relationship formalized as ‘Rensch's rule’ . Empirical studies show that taxa with male-biased SSD are more likely to satisfy Rensch's rule and that a taxon's mean SSD is negatively correlated with allometric slope, implicating sexual selection on male size as an important mechanism promoting allometry for SSD. I use body length (and life-history) data from 628 (259) populations of seven species of anadromous Pacific salmon and trout (Oncorhynchus spp.) to show that in this genus life-history variation appears to regulate patterns of allometry both within and between species. Although all seven species have intraspecific allometric slopes of less than 1, contrary to expectation slope is unrelated to species' mean SSD, but is instead negatively correlated with two life-history variables: the species' mean marine age and variation in marine age. Second, because differences in marine age among species render SSD and body size uncorrelated, the interspecific slope is isometric. Together, these results provide an example of how evolutionary divergence in life history among related species can affect patterns of allometry for SSD across taxonomic scales. PMID:15695207

The rate-size trade-off structures intraspecific variation in Daphnia ambigua life history parameters.

PubMed

DeLong, John P; Hanley, Torrance C

2013-01-01

The identification of trade-offs is necessary for understanding the evolution and maintenance of diversity. Here we employ the supply-demand (SD) body size optimization model to predict a trade-off between asymptotic body size and growth rate. We use the SD model to quantitatively predict the slope of the relationship between asymptotic body size and growth rate under high and low food regimes and then test the predictions against observations for Daphnia ambigua. Close quantitative agreement between observed and predicted slopes at both food levels lends support to the model and confirms that a 'rate-size' trade-off structures life history variation in this population. In contrast to classic life history expectations, growth and reproduction were positively correlated after controlling for the rate-size trade-off. We included 12 Daphnia clones in our study, but clone identity explained only some of the variation in life history traits. We also tested the hypothesis that growth rate would be positively related to intergenic spacer length (i.e. the growth rate hypothesis) across clones, but we found that clones with intermediate intergenic spacer lengths had larger asymptotic sizes and slower growth rates. Our results strongly support a resource-based optimization of body size following the SD model. Furthermore, because some resource allocation decisions necessarily precede others, understanding interdependent life history traits may require a more nested approach.

Reflex syncope, anxiety level, and family history of cardiovascular disease in young women: case-control study.

PubMed

Zyśko, D; Szewczuk-Bogusławska, M; Kaczmarek, M; Agrawal, A K; Rudnicki, J; Gajek, J; Melander, O; Sutton, R; Fedorowski, A

2015-02-01

Anxiety is an emotion, which stimulates sympathetic nervous outflow potentially facilitating vasovagal reflex syncope (VVS) but reports on anxiety levels in patients with VVS are sparse. We studied anxiety levels in young women (21-40 years) referred for unexplained transient loss of consciousness (TLOC), and age-matched female controls with or without past history of TLOC (≈probable VVS). Referred patients underwent head-up tilt (HUT) according to current ESC Guidelines. State and Trait Anxiety Inventory questionnaire evaluated anxiety levels plus a questionnaire explored risk factors for cardiovascular disease (CVD). Sixty-five of 91 women were diagnosed with VVS on HUT. Among 549 controls, 223 (40.6%) reported at least one episode of TLOC. State-anxiety level in patients with VVS undergoing HUT (42.4 ± 9.3) was higher compared with both controls with (38.3 ± 10.2; P < 0.01) and without past TLOC history (35.9 ± 9.8; P < 0.001). Trait anxiety in patients with VVS (42.7 ± 8.4), and controls with TLOC history (42.4 ± 8.4) was higher compared with controls without TLOC history (39.7 ± 8.5; P < 0.01). In the logistic regression using controls without TLOC as reference, both VVS diagnosis and past history of TLOC were associated with family history of CVD [odds ratio (OR) 2.4, 95% confidence interval (CI), 1.3-4.4; P = 0.007, and 2.3, 1.4-3.6; P = 0.001, respectively], and this association was independent of anxiety level. Trait anxiety and family history of CVD are increased in both young women with VVS and controls with history of TLOC. However, the height of anxiety level does not explain CVD heredity and other mechanisms may link syncope with CVD. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

Potential fitness benefits of the half-pounder life history in Klamath River steelhead

USGS Publications Warehouse

Hodge, Brian W.; Wilzbach, Peggy; Duffy, Walter G.

2014-01-01

Steelhead Oncorhynchus mykiss from several of the world's rivers display the half-pounder life history, a variant characterized by an amphidromous (and, less often, anadromous) return to freshwater in the year of initial ocean entry. We evaluated factors related to expression of the half-pounder life history in wild steelhead from the lower Klamath River basin, California. We also evaluated fitness consequences of the half-pounder phenotype using a simple life history model that was parameterized with our empirical data and outputs from a regional survival equation. The incidence of the half-pounder life history differed among subbasins of origin and smolt ages. Precocious maturation occurred in approximately 8% of half-pounders and was best predicted by individual length in freshwater preceding ocean entry. Adult steelhead of the half-pounder phenotype were smaller and less fecund at age than adult steelhead of the alternative (ocean contingent) phenotype. However, our data suggest that fish of the half-pounder phenotype are more likely to spawn repeatedly than are fish of the ocean contingent phenotype. Models predicted that if lifetime survivorship were equal between phenotypes, the fitness of the half-pounder phenotype would be 17–28% lower than that of the ocean contingent phenotype. To meet the condition of equal fitness between phenotypes would require that first-year ocean survival be 21–40% higher among half-pounders in freshwater than among their cohorts at sea. We concluded that continued expression of the half-pounder phenotype is favored by precocious maturation and increased survival relative to that of the ocean contingent phenotype.

Premature menopause in young breast cancer: effects on quality of life and treatment interventions

PubMed Central

Partridge, Ann H.

2013-01-01

Many young women are at increased risk for premature menopause following adjuvant treatment for breast cancer. These women must deal with consequences of menopause, including loss of fertility and physiologic symptoms such as night sweats, hot flashes, vaginal dryness, and weight gain. These symptoms can be particularly distressing for young women and can adversely affect both health-related and psychosocial quality of life (QOL). While there are a wide range of pharmacologic and non-pharmacologic interventions available to help with these symptoms and in turn, improve QOL, there is little data available about the use and efficacy of these interventions in younger women who become menopausal as a result of their breast cancer treatment. Future studies should focus on this vulnerable population, with the goal of identifying effective strategies to relieve symptoms and improve quality of life in young breast cancer survivors. PMID:23819028

Experiences of using life histories with health workers in post-conflict and crisis settings: methodological reflections

PubMed Central

Namakula, Justine; Alonso-Garbayo, Alvaro; Wurie, Haja; Theobald, Sally; Mashange, Wilson; Ros, Bandeth; Buzuzi, Stephen; Mangwi, Richard; Martineau, Tim

2017-01-01

Abstract Introduction: Life history is a research tool which has been used primarily in sociology and anthropology to document experiences of marginalized individuals and communities. It has been less explored in relation to health system research. In this paper, we examine our experience of using life histories to explore health system trajectories coming out of conflict through the eyes of health workers. Methods: Life histories were used in four inter-related projects looking at health worker incentives, the impact of Ebola on health workers, deployment policies, and gender and leadership in the health sector. In total 244 health workers of various cadres were interviewed in Uganda, Sierra Leone, Zimbabwe and Cambodia. The life histories were one element within mixed methods research. Results: We examine the challenges faced and how these were managed. They arose in relation to gaining access, data gathering, and analysing and presenting findings from life histories. Access challenges included lack of familiarity with the method, reluctance to expose very personal information and sentiments, lack of trust in confidentiality, particularly given the traumatized contexts, and, in some cases, cynicism about research and its potential to improve working lives. In relation to data gathering, there was variable willingness to draw lifelines, and some reluctance to broach sensitive topics, particularly in contexts where policy-related issues and legitimacy are commonly still contested. Presentation of lifeline data without compromising confidentiality is also an ethical challenge. Conclusion: We discuss how these challenges were (to a large extent) surmounted and conclude that life histories with health staff can be a very powerful tool, particularly in contexts where routine data sources are absent or weak, and where health workers constitute a marginalized community (as is often the case for mid-level cadres, those serving in remote areas, and staff who have lived

Life histories of female elementary teachers and their science/teacher role construction

NASA Astrophysics Data System (ADS)

Ramseur, Aletha Johnson

The research conducted in this study focuses on life histories of female elementary teachers and their science/teacher role construction. Identity theorists argue that the self consists of a collection of identities founded on occupying a particular role. Who we are depends on the roles we occupy. These roles are often referred to as "role identities". In the case of these participants, many role identities (mother, wife, sibling, and teacher) exist. This study focuses primarily on their (science) teacher role identity. Literature on women's lives, as learners and teachers, suggest that women's experiences, currently and throughout history influenced their teacher role construction. There is however, little knowledge of women's lives as elementary teachers of science and the affect of their experiences, currently and throughout history, on their (science) teacher identity construction. Schools delineated by race, class, and gender relations, are similar to other sectors of society's, social and cultural spheres within which race, class, and gender identities are constructed. Using in-depth-interviews female elementary teachers were encouraged to actively reconstruct their life and work-life experiences focusing on family, school and science interactions. They addressed the intellectual and emotional connections between their life and work experiences by focusing on details of their past and present experiences and examining the meaning of those experiences. It was the scrutiny of these connections between their life and work experiences, the meaning derived from them and historical events, and the constraints imposed on their personal choices by broader power relations, such as those of class, race, and gender that informed why we teach, how we teach, and what we teach.

Individual covariation in life-history traits: seeing the trees despite the forest

USGS Publications Warehouse

Cam, E.; Link, W.A.; Cooch, E.G.; Monnat, J.-Y.; Danchin, E.

2002-01-01

We investigated the influence of age on survival and breeding rates in a long-lived species Rissa tridactyla using models with individual random effects permitting variation and covariation in fitness components among individuals. Differences in survival or breeding probabilities among individuals are substantial, and there was positive covariation between survival and breeding probability; birds that were more likely to survive were also more likely to breed, given that they survived. The pattern of age-related variation in these rates detected at the individual level differed from that observed at the population level. Our results provided confirmation of what has been suggested by other investigators: within-cohort phenotypic selection can mask senescence. Although this phenomenon has been extensively studied in humans and captive animals, conclusive evidence of the discrepancy between population-level and individual-level patterns of age-related variation in life-history traits is extremely rare in wild animal populations. Evolutionary studies of the influence of age on life-history traits should use approaches differentiating population level from the genuine influence of age: only the latter is relevant to theories of life-history evolution. The development of models permitting access to individual variation in fitness is a promising advance for the study of senescence and evolutionary processes.

Growth patterns and life-history strategies in Placodontia (Diapsida: Sauropterygia)

PubMed Central

Klein, Nicole; Neenan, James M.; Scheyer, Torsten M.; Griebeler, Eva Maria

2015-01-01

Placodontia is a clade of durophagous, near shore marine reptiles from Triassic sediments of modern-day Europe, Middle East and China. Although much is known about their primary anatomy and palaeoecology, relatively little has been published regarding their life history, i.e. ageing, maturation and growth. Here, growth records derived from long bone histological data of placodont individuals are described and modelled to assess placodont growth and life-history strategies. Growth modelling methods are used to confirm traits documented in the growth record (age at onset of sexual maturity, age when asymptotic length was achieved, age at death, maximum longevity) and also to estimate undocumented traits. Based on these growth models, generalized estimates of these traits are established for each taxon. Overall differences in bone tissue types and resulting growth curves indicate different growth patterns and life-history strategies between different taxa of Placodontia. Psephoderma and Paraplacodus grew with lamellar-zonal bone tissue type and show growth patterns as seen in modern reptiles. Placodontia indet. aff. Cyamodus and some Placodontia indet. show a unique combination of fibrolamellar bone tissue regularly stratified by growth marks, a pattern absent in modern sauropsids. The bone tissue type of Placodontia indet. aff. Cyamodus and Placodontia indet. indicates a significantly increased basal metabolic rate when compared with modern reptiles. Double lines of arrested growth, non-annual rest lines in annuli, and subcycles that stratify zones suggest high dependence of placodont growth on endogenous and exogenous factors. Histological and modelled differences within taxa point to high individual developmental plasticity but sexual dimorphism in growth patterns and the presence of different taxa in the sample cannot be ruled out. PMID:26587259

Entanglement is a costly life-history stage in large whales.

PubMed

van der Hoop, Julie; Corkeron, Peter; Moore, Michael

2017-01-01

Individuals store energy to balance deficits in natural cycles; however, unnatural events can also lead to unbalanced energy budgets. Entanglement in fishing gear is one example of an unnatural but relatively common circumstance that imposes energetic demands of a similar order of magnitude and duration of life-history events such as migration and pregnancy in large whales. We present two complementary bioenergetic approaches to estimate the energy associated with entanglement in North Atlantic right whales, and compare these estimates to the natural energetic life history of individual whales. Differences in measured blubber thicknesses and estimated blubber volumes between normal and entangled, emaciated whales indicate between 7.4 × 10 10  J and 1.2 × 10 11  J of energy are consumed during the course to death of a lethal entanglement. Increased thrust power requirements to overcome drag forces suggest that when entangled, whales require 3.95 × 10 9 to 4.08 × 10 10  J more energy to swim. Individuals who died from their entanglements performed significantly more work (energy expenditure × time) than those that survived; entanglement duration is therefore critical in determining whales' survival. Significant sublethal energetic impacts also occur, especially in reproductive females. Drag from fishing gear contributes up to 8% of the 4-year female reproductive energy budget, delaying time of energetic equilibrium (to restore energy lost by a particular entanglement) for reproduction by months to years. In certain populations, chronic entanglement in fishing gear can be viewed as a costly unnatural life-history stage, rather than a rare or short-term incident.

All in the Family? The Structure and Meaning of Family Life among Young People

ERIC Educational Resources Information Center

Turtiainen, Pirjo; Karvonen, Sakari; Rahkonen, Ossi

2007-01-01

The aim of this article is to explore young people's everyday family life with special reference to the use of time. First, we ask what kinds of activities young people engage in with their families, what kinds of families spend most time together, and whether this has changed over time. These analyses were based on two surveys conducted in the…

Genetic and life-history consequences of extreme climate events

PubMed Central

Mangel, Marc; Jesensek, Dusan; Garza, John Carlos; Crivelli, Alain J.

2017-01-01

Climate change is predicted to increase the frequency and intensity of extreme climate events. Tests on empirical data of theory-based predictions on the consequences of extreme climate events are thus necessary to understand the adaptive potential of species and the overarching risks associated with all aspects of climate change. We tested predictions on the genetic and life-history consequences of extreme climate events in two populations of marble trout Salmo marmoratus that have experienced severe demographic bottlenecks due to flash floods. We combined long-term field and genotyping data with pedigree reconstruction in a theory-based framework. Our results show that after flash floods, reproduction occurred at a younger age in one population. In both populations, we found the highest reproductive variance in the first cohort born after the floods due to a combination of fewer parents and higher early survival of offspring. A small number of parents allowed for demographic recovery after the floods, but the genetic bottleneck further reduced genetic diversity in both populations. Our results also elucidate some of the mechanisms responsible for a greater prevalence of faster life histories after the extreme event. PMID:28148745

Genetic and life-history consequences of extreme climate events.

PubMed

Vincenzi, Simone; Mangel, Marc; Jesensek, Dusan; Garza, John Carlos; Crivelli, Alain J

2017-02-08

Climate change is predicted to increase the frequency and intensity of extreme climate events. Tests on empirical data of theory-based predictions on the consequences of extreme climate events are thus necessary to understand the adaptive potential of species and the overarching risks associated with all aspects of climate change. We tested predictions on the genetic and life-history consequences of extreme climate events in two populations of marble trout Salmo marmoratus that have experienced severe demographic bottlenecks due to flash floods. We combined long-term field and genotyping data with pedigree reconstruction in a theory-based framework. Our results show that after flash floods, reproduction occurred at a younger age in one population. In both populations, we found the highest reproductive variance in the first cohort born after the floods due to a combination of fewer parents and higher early survival of offspring. A small number of parents allowed for demographic recovery after the floods, but the genetic bottleneck further reduced genetic diversity in both populations. Our results also elucidate some of the mechanisms responsible for a greater prevalence of faster life histories after the extreme event. © 2017 The Author(s).

Genetic effects on life-history traits in the Glanville fritillary butterfly.

PubMed

Duplouy, Anne; Wong, Swee C; Corander, Jukka; Lehtonen, Rainer; Hanski, Ilkka

2017-01-01

Adaptation to local habitat conditions may lead to the natural divergence of populations in life-history traits such as body size, time of reproduction, mate signaling or dispersal capacity. Given enough time and strong enough selection pressures, populations may experience local genetic differentiation. The genetic basis of many life-history traits, and their evolution according to different environmental conditions remain however poorly understood. We conducted an association study on the Glanville fritillary butterfly, using material from five populations along a latitudinal gradient within the Baltic Sea region, which show different degrees of habitat fragmentation. We investigated variation in 10 principal components, cofounding in total 21 life-history traits, according to two environmental types, and 33 genetic SNP markers from 15 candidate genes. We found that nine SNPs from five genes showed strong trend for trait associations ( p -values under 0.001 before correction). These associations, yet non-significant after multiple test corrections, with a total number of 1,086 tests, were consistent across the study populations. Additionally, these nine genes also showed an allele frequency difference between the populations from the northern fragmented versus the southern continuous landscape. Our study provides further support for previously described trait associations within the Glanville fritillary butterfly species across different spatial scales. Although our results alone are inconclusive, they are concordant with previous studies that identified these associations to be related to climatic changes or habitat fragmentation within the Åland population.

Genetic effects on life-history traits in the Glanville fritillary butterfly

PubMed Central

Corander, Jukka

2017-01-01

Background Adaptation to local habitat conditions may lead to the natural divergence of populations in life-history traits such as body size, time of reproduction, mate signaling or dispersal capacity. Given enough time and strong enough selection pressures, populations may experience local genetic differentiation. The genetic basis of many life-history traits, and their evolution according to different environmental conditions remain however poorly understood. Methods We conducted an association study on the Glanville fritillary butterfly, using material from five populations along a latitudinal gradient within the Baltic Sea region, which show different degrees of habitat fragmentation. We investigated variation in 10 principal components, cofounding in total 21 life-history traits, according to two environmental types, and 33 genetic SNP markers from 15 candidate genes. Results We found that nine SNPs from five genes showed strong trend for trait associations (p-values under 0.001 before correction). These associations, yet non-significant after multiple test corrections, with a total number of 1,086 tests, were consistent across the study populations. Additionally, these nine genes also showed an allele frequency difference between the populations from the northern fragmented versus the southern continuous landscape. Discussion Our study provides further support for previously described trait associations within the Glanville fritillary butterfly species across different spatial scales. Although our results alone are inconclusive, they are concordant with previous studies that identified these associations to be related to climatic changes or habitat fragmentation within the Åland population. PMID:28560112

Whale baleen trace element signatures: a predictor of environmental life history?

NASA Astrophysics Data System (ADS)

Wilcox Freeburg, E.; Brault, S.; Mayo, C.; Oktay, S.; Hannigan, R.

2009-12-01

The analysis of trace element composition of biogenic structures (e.g., otoliths, feathers) by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) provides unique insights into the environmental life history of individuals. We studied the trace element chemistry of right whale baleens in an attempt to reconstruct migration patterns. Though much is known about the feeding and breeding habitats of these whales, little is known about the location in which they spend most of their adult years. Baleens, made of keratin, grow continuously and are metabolically inactive. Previous work showed that the stable isotope chemistry along the length of a baleen records changes in diet, such as weaning. Baleen chemistry should, therefore, also record the environmental life history of the individual. Trace metal chemistry along a single baleen plate from a right whale were analyzed by LA-ICP-MS. Semi-quantitative elemental signatures were obtained using NIST 612 (glass standard) and MACS-3 (calcium carbonate standard). These concentrations were then compared for accuracy to acid digested baleen laterally adjacent to the laser ablation site via aqueous ICP-MS. Elemental chemistry was compared to known feeding/breeding locations of the individual (water chemistry). Using these comparisons as well as principal components analysis, life history of the individual was reconstructed. Development of an in-house keratin standard is in progress and is expected to strengthen the confidence in results. Future work is expected to bring a more complete knowledge of right whale wintering habits.

A Focus into the Charity "Young Enterprise Northern Ireland" and How Effective Their "Company Programme" Is at Increasing "Life Skills" in Young People

ERIC Educational Resources Information Center

McVeigh, Francis

2014-01-01

Purpose - This research project has investigated the "Company Programme" of the charity YE and how effective it is at increasing Life Skills in young people. Data has been obtained using student questionnaires and teacher interviews. Previous studies have been completed on "Life Skills" and "Enterprise Programmes",…

Voices of Young People with a History of Specific Language Impairment (SLI) in the First Year of Post-16 Education

ERIC Educational Resources Information Center

Palikara, Olympia; Lindsay, Geoff; Dockrell, Julie E.

2009-01-01

Background: Giving young people more and better opportunities to have their voices heard is a key feature of current educational policy and research internationally and in the UK. Aims: To examine the views of young people with a history of specific language impairment (SLI) as they entered post-16 education. Methods & Procedures: A total of…

Size-Mediated Tradeoffs in Life-History Traits in Dusky Salamanders

Treesearch

Richard C. Bruce

2013-01-01

Among salamanders of the genus Desmognathus, the larger species tend to be more aquatic and the smaller more terrestrial. I studied life histories in assemblages of Desmognathus in the southern Blue Ridge Mountains of North Carolina at sites in the Cowee and southern Nantahala Mountains. Traits evaluated included mortality/survival...

[Attitude toward sexual life of young adult medical and nursing students].

PubMed

Mroczek, Bozena; Karakiewicz, Beata

2004-01-01

Nowadays can observe not only changes of views on human sexuality but also of its nomenclature. These changes also apply to the issues related to human sexuality which plays an role in psychological purposes. The article discusses psychological and pedagogical aspects of human sexuality on the threshold of adult life. 83 students of post-GCSE faculties of the medical school were interviewed. The aim of the study was to determine the attitude towards sexual life expressed by young people entering their adult life. The study tool was a questionnaire technique. Results were statistically analyzed. The results showed that: the level of knowledge of sexual life is low among adults: lack of correlation between emotional and cognitive elements of attitudes towards human sexuality; sexual behaviours depend on human sex.

A life history study of the yellow throat

USGS Publications Warehouse

Stewart, R.E.

1953-01-01

Investigations concerning the life history of the Yellow-throat were made in southern Michigan during the spring and summer of 1938. Supplementary information was also obtained at Arlington, Virginia, in 1940 and at the Patuxent Research Refuge, Maryland, in 1947.....Resident males established territories almost immediately upon arrival in spring. In southern Michigan some resident males arrived at least as soon as, if not before, transient males. Most females appeared on their nesting ground about a week later. Adults were engaged in nesting activities from the time of their arrival in spring until the advent of the post-nuptial molt in late summer.....Typical Yellow-throat habitat consists of a mixture of a dense herbaceous vegetation and small woody plants in damp or wet situations. At Ann Arbor, the Yellow-throat was a common breeding species in its restricted suitable habitat. The population density in one area of suitable habitat was about 69 territorial males per 100 acres. Of 11 territorial males that were intensively studied, one was polygamous (with two mates), nine were monogamous, and one was probably monogamous (with at least one mate).....The song of the individual Yellow-throat was heard throughout the breeding season except for the courtship period. Two major types of song were the common song given while perched, and an occasional, more elaborate, flight song. Most males sing in spurts, singing at fairly regular intervals for a considerable period and then abruptly ceasing for another period. The vocabulary of both sexes included several types of call notes that appeared either to have special functions or to represent outward expressions of distinct emotional states of the bird.....Resident males were antagonistic toward each other throughout the breeding season. Most remained on well-established territories during this period. Territories of 10 monogamous males ranged in size from .8 to 1.8 acres but the territory of one polygamous male occupied

Acne Vulgaris and Quality of Life Among Young Adults in South India

PubMed Central

Durai, Priya Cinna T; Nair, Dhanya G

2015-01-01

Acne vulgaris is a chronic condition affecting more than 85% of adolescents and young adults. It is one of the most common diseases affecting humanity and its impact on quality of life (QoL) is important. The impact of acne on QoL in Indian patients remains undocumented. The study was undertaken to detect the impact of acne vulgaris and related factors that may influence the QoL. Materials and Methods: This was a hospital-based, prospective, cross-sectional, prestructured, questionnaire-based study done on 140 consenting individuals, who attended the Dermatology outpatient department. Acne vulgaris was graded using simple grading system. QoL was measured using a combination of skin disease-specific (Dermatological Life Quality Index (DLQI)) and acne-specific (Cardiff Acne Disability Index (CADI)) questionnaires. Results: Majority of our study population were students (103, 73.6%). Face (139, 99.3%) was the commonest site of acne and comedones 133, 95% were the commonest type of lesion. Most of the individuals 66, 47.1% were observed to have grade 1 acne. The mean DLQI score was 6.91 and the mean CADI score was 5.2. Association between the scores was statistically significant. Age, occupation, marital status, family, and treatment history played a role in affecting the QoL. Diet, smoking, and alcohol did not influence the QoL. Conclusion: Though acne had impact on patient's QoL, it was less severe in our study. It is important for health professionals to incorporate QoL measurements when managing acne patients to provide better and appropriate care. PMID:25657394

Psychometrics and life history strategy: the structure and validity of the High K Strategy Scale.

PubMed

Copping, Lee T; Campbell, Anne; Muncer, Steven

2014-03-22

In this paper, we critically review the conceptualization and implementation of psychological measures of life history strategy associated with Differential K theory. The High K Strategy Scale (HKSS: Giosan, 2006) was distributed to a large British sample (n = 809) with the aim of assessing its factor structure and construct validity in relation to theoretically relevant life history variables: age of puberty, age of first sexual encounter, and number of sexual partners. Exploratory and confirmatory factor analyses indicated that the HKSS in its current form did not show an adequate statistical fit to the data. Modifications to improve fit indicated four correlated factors (personal capital, environmental stability, environmental security, and social capital). Later puberty in women was positively associated with measures of the environment and personal capital. Among men, contrary to Differential K predictions but in line with female mate preferences, earlier sexual debut and more sexual partners were positively associated with more favorable environments and higher personal and social capital. We raise concerns about the use of psychometric indicators of lifestyle and personality as proxies for life history strategy when they have not been validated against objective measures derived from contemporary life history theory and when their status as causes, mediators, or correlates has not been investigated.

Voices of Young Adults with Autism and Their Perspective on Life Choices after Secondary Education

ERIC Educational Resources Information Center

Galler, Susan

2013-01-01

The purpose of this phenomenological qualitative research study was to explore how young adults who have an autism spectrum disorder perceive their life choices after secondary education. The focus participants in the sample were young adults with Autism Spectrum Disorder (ASD). For the purpose of this research, ASD includes autism and Asperger's…

Life-Course Pathways and the Psychosocial Adjustment of Young Adult Women

ERIC Educational Resources Information Center

Amato, Paul R.; Kane, Jennifer B.

2011-01-01

We examined 7 life-course pathways from adolescence through the early adult years and their links with general health and psychosocial adjustment among 2,290 women from the National Longitudinal Study of Adolescent Health. Young women who followed a pathway involving college attendance to full-time employment with no family-formation transitions…

The Inter-Life Project: Inter-Cultural Spaces for Young People to Use Creative Practices and Research to Assist with Life Changes and Transition

ERIC Educational Resources Information Center

Lally, Vic; Sclater, Madeleine

2012-01-01

The aim of the Inter-Life Project was to investigate the use of virtual worlds and creative practices to support the acquisition of transition skills for young people to enhance their management of important life events. In particular, the authors have been investigating the role of the Inter-Life virtual worlds in supporting the development of…

Distribution of early life history stages of fishes in selected pools of the upper Mississippi River

USGS Publications Warehouse

Holland, L.E.

1986-01-01

Effective management of the fishery resources of the Upper Mississippi River and successful mitigation of the loss of critical habitat depend in part on an understanding of the reproductive and early life history requirements of the affected fishes. However, little is known about the use of nursery areas by fishes in the river. Of the nearly 130 species identified in the adult ichthyofauna, only a few are represented proportionally in the available data on early life stages because study designs have not included consideration of the early stages, collection gears have not adequately sampled the young, and eggs and larvae of some species are difficult to sample by conventional approaches. For the species collected, information is available on seasonal variations in total densities, composition, and catch among different habitat types. However, the data are most accurate for species with buoyant early life stages, such as freshwater drum (Aplodinotus grunniens) and gizzard shad (Dorosoma cepedianum). Eggs and larvae of freshwater drum dominate collections made in the main channel, whereas other larval fishes are usually most abundant in backwater habitats. The species found there usually deposit eggs on the substrate or on vegetation. Habitat preferences (as indicated by relative abundance) often shift as development proceeds and physical and behavioral changes occur in the larvae. Only limited information is available on the distribution of larvae within habitats, but it is clear that variations within habitats are significant.

The Early History of Life

NASA Astrophysics Data System (ADS)

Nisbet, E. G.; Fowler, C. M. R.

2003-12-01

The youth of the Earth is strange to us. Many of the most fundamental constraints on life may have been different, especially the oxidation state of the surface. Should we suddenly land on its Hadean or early Archean surface by some sci-fi accident, we would not recognize our home. Above, the sky may have been green or some other unworldly color, and above that the weak young Sun might have been unrecognizable to someone trying to identify it from its spectrum. Below, seismology would show a hot, comparatively low-viscosity interior, possibly with a magma ocean in the deeper part of the upper mantle (Drake and Righter, 2002; Nisbet and Walker, 1982), and a core that, though present, was perhaps rather smaller than today. The continents may have been small islands in an icy sea, mostly frozen with some leads of open water, ( Sleep et al., 2001). Into these icy oceans, huge protruding Hawaii-like volcanoes would have poured out vast far-spreading floods of komatiite lavas in immense eruptions that may have created sudden local hypercane storms to disrupt the nearby icebergs. And meteorites would rain down.Or perhaps it was not so strange, nor so violent. The child is father to the man; young Earth was mother to Old Earth. Earth had hydrogen, silicate rock below and on the surface abundant carbon, which her ancient self retains today. Moreover, Earth was oxygen-rich, as today. Today, a tiny part of the oxygen is free, as air; then the oxygen would have been in the mantle while the surface oxygen was used to handcuff the hydrogen as dihydrogen monoxide. Oxygen dihydride is dense, unlikely to fly off to space, and at the poles, rock-forming. Of all the geochemical features that make Earth unique, the initial degassing (Genesis 2 : b) and then the sustained presence of liquid water is the defining oddity of this planet. Early Earth probably also kept much of its carbon, nitrogen, and sulfur as oxide or hydride. And, after the most cataclysmic events had passed, ˜4.5 Ga

Real-Life Spatial Skills, Handedness, and Family History of Handedness

ERIC Educational Resources Information Center

Ecuyer-Dab, I.; Tremblay, T.; Joanette, Y.; Passini, R.

2005-01-01

According to Annett (1985), pronounced left hemisphere lateralization for language abilities in women, as in female absolute right-handers, limits their right hemisphere capacity and spatial abilities. This study examines the degree of handedness and the family history of non-right-handedness with respect to real-life spatial abilities in women.…

To eject or to abandon? Life history traits of hosts and parasites interact to influence the fitness payoffs of alternative anti-parasite strategies.

PubMed

Servedio, M R; Hauber, M E

2006-09-01

Hosts either tolerate avian brood parasitism or reject it by ejecting parasitic eggs, as seen in most rejecter hosts of common cuckoos, Cuculus canorus, or by abandoning parasitized clutches, as seen in most rejecter hosts of brown-headed cowbirds, Molothrus ater. What explains consistent variation between alternative rejection behaviours of hosts within the same species and across species when exposed to different types of parasites? Life history theory predicts that when parasites decrease the fitness of host offspring, but not the future reproductive success of host adults, optimal clutch size should decrease. Consistent with this prediction, evolutionarily old cowbird hosts, but not cuckoo hosts, have lower clutch sizes than related rarely- or newly parasitized species. We constructed a mathematical model to calculate the fitness payoffs of egg ejector vs. nest abandoner hosts to determine if various aspects of host life history traits and brood parasites' virulence on adult and young host fitness differentially influence the payoffs of alternative host defences. These calculations showed that in general egg ejection was a superior anti-parasite strategy to nest abandonment. Yet, increasing parasitism rates and increasing fitness values of hosts' eggs in both currently parasitized and future replacement nests led to switch points in fitness payoffs in favour of nest abandonment. Nonetheless, nest abandonment became selectively more favourable only at lower clutch sizes and only when hosts faced parasitism by a cowbird- rather than a cuckoo-type brood parasite. We suggest that, in addition to evolutionary lag and gape-size limitation, our estimated fitness differences based on life history trait variation provide new insights for the consistent differences observed in the anti-parasite rejection strategies between many cuckoo- and cowbird-hosts.

A mechanism that maintains alternative life histories in a loggerhead sea turtle population.

PubMed

Hatase, Hideo; Omuta, Kazuyoshi; Tsukamoto, Katsumi

2013-11-01

Intrapopulation variation in habitat use is commonly seen among mobile animals, yet the mechanisms maintaining it have rarely been researched among untrackable species. To investigate how alternative life histories are maintained in a population of the loggerhead sea turtle (Caretta caretta), cumulative reproductive output was evaluated and compared between small planktivores inhabiting oceanic areas (with water depths > 200 m) and large benthivores inhabiting neritic areas (depths < 200 m) that sympatrically nested at Yakushima Island, Japan, from 1986 to 2011. In total, 362 nesting females sampled in three different years were classified into the two foraging groups based on stable isotope ratios in egg yolks. There were significant differences between the two foraging groups in most recorded life history parameters (clutch size, clutch frequency, breeding frequency, and remigration intervals), with the exception of emergence success. We did not find evidence of life history trade-offs, nor age-related changes in fecundity. Over the 26-year study period, we calculated a 2.4-fold greater reproductive output for neritic foragers than for oceanic ones, accounting for breeding and clutch frequency. Temporal consistencies in stable isotope ratios and remigration intervals within females suggested that female Japanese loggerheads show fidelity to respective foraging habitats throughout the adult stage. The large difference in productivity between the two groups was unlikely to be offset by the difference in survival during the period from aboveground emergence to first reproduction, suggesting that oceanic foragers have a lower level of fitness than neritic ones. Together with an absence of genetic structure between foraging groups, we infer that alternative life histories in a loggerhead turtle population are maintained by a conditional strategy.

Bridging developmental boundaries: lifelong dietary patterns modulate life histories in a parthenogenetic insect.

PubMed

Roark, Alison M; Bjorndal, Karen A

2014-01-01

Determining the effects of lifelong intake patterns on performance is challenging for many species, primarily because of methodological constraints. Here, we used a parthenogenetic insect (Carausius morosus) to determine the effects of limited and unlimited food availability across multiple life-history stages. Using a parthenogen allowed us to quantify intake by juvenile and adult females and to evaluate the morphological, physiological, and life-history responses to intake, all without the confounding influences of pair-housing, mating, and male behavior. In our study, growth rate prior to reproductive maturity was positively correlated with both adult and reproductive lifespans but negatively correlated with total lifespan. Food limitation had opposing effects on lifespan depending on when it was imposed, as it protracted development in juveniles but hastened death in adults. Food limitation also constrained reproduction regardless of when food was limited, although decreased fecundity was especially pronounced in individuals that were food-limited as late juveniles and adults. Additional carry-over effects of juvenile food limitation included smaller adult size and decreased body condition at the adult molt, but these effects were largely mitigated in insects that were switched to ad libitum feeding as late juveniles. Our data provide little support for the existence of a trade-off between longevity and fecundity, perhaps because these functions were fueled by different nutrient pools. However, insects that experienced a switch to the limited diet at reproductive maturity seem to have fueled egg production by drawing down body stores, thus providing some evidence for a life-history trade-off. Our results provide important insights into the effects of food limitation and indicate that performance is modulated by intake both within and across life-history stages.

Divergent life histories of invasive round gobies (Neogobius melanostomus) in Lake Michigan and its tributaries

USGS Publications Warehouse

Kornis, Matthew; Weidel, Brian C.; Vander Zanden, M. Jake

2017-01-01

Round gobies (Neogobius melanostomus) have invaded benthic habitats of the Laurentian Great Lakes and connected tributary streams. Although connected, these two systems generally differ in temperature (Great Lakes are typically colder), food availability (Dreissenid mussels are more prevalent in Great Lakes), and system size and openness. Here, we compare round goby life histories from inshore Lake Michigan and adjacent tributary systems—an uncommon case study of life-history differences between connected systems. Tributary round gobies grew much faster (average length-at-age of 122.3 vs. 65.7 mm for Age 2 +  round gobies), appeared to have shorter life spans (maximum observed age of 2 vs. 5) and had lower age-at-50% maturity (1.6 vs. 2.4 years; females only) compared to gobies from Lake Michigan. In addition, tributary gobies had greater fecundity at Ages 1–2 than lake gobies, but had fewer eggs for a given body size prior to the first spawning event of the summer. We were not able to determine the cause of the observed life-history differences. Nonetheless, the observed differences in growth, maturation and longevity were consistent with known effects of water temperature, as well as predictions of life-history theory for animals at invasion fronts exposed to novel environmental conditions. The high degree of phenotypic plasticity in connected populations of this invasive species has implications for our understanding of invasive species impacts in different habitats.

Natural Selection on Female Life-History Traits in Relation to Socio-Economic Class in Pre-Industrial Human Populations

PubMed Central

Pettay, Jenni E.; Helle, Samuli; Jokela, Jukka; Lummaa, Virpi

2007-01-01

Life-history theory predicts that resource scarcity constrains individual optimal reproductive strategies and shapes the evolution of life-history traits. In species where the inherited structure of social class may lead to consistent resource differences among family lines, between-class variation in resource availability should select for divergence in optimal reproductive strategies. Evaluating this prediction requires information on the phenotypic selection and quantitative genetics of life-history trait variation in relation to individual lifetime access to resources. Here, we show using path analysis how resource availability, measured as the wealth class of the family, affected the opportunity and intensity of phenotypic selection on the key life-history traits of women living in pre-industrial Finland during the 1800s and 1900s. We found the highest opportunity for total selection and the strongest selection on earlier age at first reproduction in women of the poorest wealth class, whereas selection favoured older age at reproductive cessation in mothers of the wealthier classes. We also found clear differences in female life-history traits across wealth classes: the poorest women had the lowest age-specific survival throughout their lives, they started reproduction later, delivered fewer offspring during their lifetime, ceased reproduction younger, had poorer offspring survival to adulthood and, hence, had lower fitness compared to the wealthier women. Our results show that the amount of wealth affected the selection pressure on female life-history in a pre-industrial human population. PMID:17622351

"A Slice of Life": The Interrelationships among Art, Play and the "Real" Life of the Young Child

ERIC Educational Resources Information Center

Bhroin, Maire Ni

2007-01-01

This study examines the interrelationships among art, play and "real" life, as perceived by young children. Twenty-one children aged four and five in their first year of formal schooling in Ireland, were observed during art-related play activities and classes over a period of four months in 2004. Research data consisted of art works…

The Treatment of Geological Time & the History of Life on Earth in High School Biology Textbooks

ERIC Educational Resources Information Center

Summers, Gerald; Decker, Todd; Barrow, Lloyd

2007-01-01

In spite of the importance of geological time in evolutionary biology, misconceptions about historical events in the history of life on Earth are common. Glenn (1990) has documented a decline from 1960 to 1989 in the amount of space devoted to the history of life in high school earth science textbooks, but we are aware of no similar study in…

Intrapopulation Genome Size Variation in D. melanogaster Reflects Life History Variation and Plasticity

PubMed Central

Ellis, Lisa L.; Huang, Wen; Quinn, Andrew M.; Ahuja, Astha; Alfrejd, Ben; Gomez, Francisco E.; Hjelmen, Carl E.; Moore, Kristi L.; Mackay, Trudy F. C.; Johnston, J. Spencer; Tarone, Aaron M.

2014-01-01

We determined female genome sizes using flow cytometry for 211 Drosophila melanogaster sequenced inbred strains from the Drosophila Genetic Reference Panel, and found significant conspecific and intrapopulation variation in genome size. We also compared several life history traits for 25 lines with large and 25 lines with small genomes in three thermal environments, and found that genome size as well as genome size by temperature interactions significantly correlated with survival to pupation and adulthood, time to pupation, female pupal mass, and female eclosion rates. Genome size accounted for up to 23% of the variation in developmental phenotypes, but the contribution of genome size to variation in life history traits was plastic and varied according to the thermal environment. Expression data implicate differences in metabolism that correspond to genome size variation. These results indicate that significant genome size variation exists within D. melanogaster and this variation may impact the evolutionary ecology of the species. Genome size variation accounts for a significant portion of life history variation in an environmentally dependent manner, suggesting that potential fitness effects associated with genome size variation also depend on environmental conditions. PMID:25057905

Niche partitioning in sympatric Gorilla and Pan from Cameroon: implications for life history strategies and for reconstructing the evolution of hominin life history.

PubMed

Macho, Gabriele A; Lee-Thorp, Julia A

2014-01-01

Factors influencing the hominoid life histories are poorly understood, and little is known about how ecological conditions modulate the pace of their development. Yet our limited understanding of these interactions underpins life history interpretations in extinct hominins. Here we determined the synchronisation of dental mineralization/eruption with brain size in a 20th century museum collection of sympatric Gorilla gorilla and Pan troglodytes from Central Cameroon. Using δ13C and δ15N of individuals' hair, we assessed whether and how differences in diet and habitat use may have impacted on ape development. The results show that, overall, gorilla hair δ13C and δ15N values are more variable than those of chimpanzees, and that gorillas are consistently lower in δ13C and δ15N compared to chimpanzees. Within a restricted, isotopically-constrained area, gorilla brain development appears delayed relative to dental mineralization/eruption [or dental development is accelerated relative to brains]: only about 87.8% of adult brain size is attained by the time first permanent molars come into occlusion, whereas it is 92.3% in chimpanzees. Even when M1s are already in full functional occlusion, gorilla brains lag behind those of chimpanzee (91% versus 96.4%), relative to tooth development. Both bootstrap analyses and stable isotope results confirm that these results are unlikely due to sampling error. Rather, δ15N values imply that gorillas are not fully weaned (physiologically mature) until well after M1 are in full functional occlusion. In chimpanzees the transition from infant to adult feeding appears (a) more gradual and (b) earlier relative to somatic development. Taken together, the findings are consistent with life history theory that predicts delayed development when non-density dependent mortality is low, i.e. in closed habitats, and with the "risk aversion" hypothesis for frugivorous species as a means to avert starvation. Furthermore, the results highlight

Niche Partitioning in Sympatric Gorilla and Pan from Cameroon: Implications for Life History Strategies and for Reconstructing the Evolution of Hominin Life History

PubMed Central

Macho, Gabriele A.; Lee-Thorp, Julia A.

2014-01-01

Factors influencing the hominoid life histories are poorly understood, and little is known about how ecological conditions modulate the pace of their development. Yet our limited understanding of these interactions underpins life history interpretations in extinct hominins. Here we determined the synchronisation of dental mineralization/eruption with brain size in a 20th century museum collection of sympatric Gorilla gorilla and Pan troglodytes from Central Cameroon. Using δ13C and δ15N of individuals’ hair, we assessed whether and how differences in diet and habitat use may have impacted on ape development. The results show that, overall, gorilla hair δ13C and δ15N values are more variable than those of chimpanzees, and that gorillas are consistently lower in δ13C and δ15N compared to chimpanzees. Within a restricted, isotopically-constrained area, gorilla brain development appears delayed relative to dental mineralization/eruption [or dental development is accelerated relative to brains]: only about 87.8% of adult brain size is attained by the time first permanent molars come into occlusion, whereas it is 92.3% in chimpanzees. Even when M1s are already in full functional occlusion, gorilla brains lag behind those of chimpanzee (91% versus 96.4%), relative to tooth development. Both bootstrap analyses and stable isotope results confirm that these results are unlikely due to sampling error. Rather, δ15N values imply that gorillas are not fully weaned (physiologically mature) until well after M1 are in full functional occlusion. In chimpanzees the transition from infant to adult feeding appears (a) more gradual and (b) earlier relative to somatic development. Taken together, the findings are consistent with life history theory that predicts delayed development when non-density dependent mortality is low, i.e. in closed habitats, and with the “risk aversion” hypothesis for frugivorous species as a means to avert starvation. Furthermore, the results

Managing the emotional aspects of end of life care for children and young people.

PubMed

Pearson, Helen

2010-09-01

Caring for a child at the end of life stage is one of the greatest challenges a nurse can encounter in practice. The way professionals help support, maintain and give comfort to the child and his or her family helps shape the experience the young patient is about to face. Whatever the stage of your nursing career it is likely you will provide end of life care to a child or young person and their family. This article is designed to help enable professionals to cope emotionally and provide the best quality of care in an emotionally charged situation. The information contained may be used as a guidance tool through is challenging and difficult time.

The Surprising History of Claims for Life on the Sun

NASA Astrophysics Data System (ADS)

Crowe, Michael J.

2011-11-01

Because astronomers are now convinced that it is impossible for life, especially intelligent life, to exist on the Sun and stars, it might be assumed that astronomers have always held this view. This paper shows that throughout most of the history of astronomy, some intellectuals, including a number of well-known astronomers, have advocated the existence of intelligent life on our Sun and thereby on stars. Among the more prominent figures discussed are Nicolas of Cusa, Giordano Bruno, William Whiston, Johann Bode, Roger Boscovich, William Herschel, Auguste Comte, Carl Gauss, Thomas Dick, John Herschel, and François Arago. One point in preparing this paper is to show differences between the astronomy of the past and that of the present.

Life history linked to immune investment in developing amphibians.

PubMed

Woodhams, Douglas C; Bell, Sara C; Bigler, Laurent; Caprioli, Richard M; Chaurand, Pierre; Lam, Brianna A; Reinert, Laura K; Stalder, Urs; Vazquez, Victoria M; Schliep, Klaus; Hertz, Andreas; Rollins-Smith, Louise A

2016-01-01

The broad diversity of amphibian developmental strategies has been shaped, in part, by pathogen pressure, yet trade-offs between the rate of larval development and immune investment remain poorly understood. The expression of antimicrobial peptides (AMPs) in skin secretions is a crucial defense against emerging amphibian pathogens and can also indirectly affect host defense by influencing the composition of skin microbiota. We examined the constitutive or induced expression of AMPs in 17 species at multiple life-history stages. We found that AMP defenses in tadpoles of species with short larval periods (fast pace of life) were reduced in comparison with species that overwinter as tadpoles and grow to a large size. A complete set of defensive peptides emerged soon after metamorphosis. These findings support the hypothesis that species with a slow pace of life invest energy in AMP production to resist potential pathogens encountered during the long larval period, whereas species with a fast pace of life trade this investment in defense for more rapid growth and development.

Child Abuse in Young, HIV-Positive Women: Linkages to Risk

PubMed Central

Clum, Gretchen A.; Andrinopoulos, Katherine; Muessig, Kathryn; Ellen, Jonathan M.

2010-01-01

In this article we explore the lives of young women living with HIV who experienced physical and/or sexual abuse in childhood. Using a modified version of the Life Story Interview, 40 women recruited from HIV clinics in three different states participated in a qualitative interview. Interviews covered abuse experiences, cognitive and emotional consequences of abuse, coping strategies, and sexual behavior and relationships. Overall, these young women had complex abuse histories, often experiencing more than one type of abuse in the context of other difficult life events. Avoidance and substance use were frequently utilized as coping strategies for abuse-related distress. Young women reported sexual and relationship concerns, including avoidance of sex, sexual dysfunction, sex as a trigger for abuse memories, and difficulty establishing intimacy and trust. Relationships between abuse-related reactions and sexual risk behavior, as well as recommendations for interventions, are discussed. PMID:19949224

Learning to Be Froebelian: Student Teachers' Life Histories 1952-1965

ERIC Educational Resources Information Center

Smedley, Sue; Hoskins, Kate

2017-01-01

Drawing on the life histories of nine women who were trained at Froebel College in the 1950s and 1960s, this paper examines the women's narratives as Froebelian student teachers and explores their remembered constructions of their experiences. Using an analytical framework underpinned by theories of identity and language their stories are shown to…

Fluctuating asymmetry and human male life-history traits in rural Belize.

PubMed Central

Waynforth, D

1998-01-01

Fluctuating asymmetry (FA), used as a measure of phenotypic quality, has proven to be a useful predictor of human life-history variation, but nothing is known about its effects in humans living in higher fecundity and mortality conditions, typical before industrialization and the demographic transition. In this research, I analyse data on male life histories for a relatively isolated population in rural Belize. Some of the 56 subjects practise subsistence-level slash-and-burn farming, and others are involved in the cash economy. Fecundity levels are quite high in this population, with men over the age of 40 averaging over eight children. Low FA successfully predicted lower morbidity and more offspring fathered, and was marginally associated with a lower age at first reproduction and more lifetime sex partners. These results indicate that FA may be important in predicting human performance in fecundity and morbidity in predemographic transition conditions. PMID:9744105

The contribution of developmental experience vs. condition to life history, trait variation, and individual differences