Women and Men in Sport Performance: The Gender Gap has not Evolved since 1983.

PubMed

Thibault, Valérie; Guillaume, Marion; Berthelot, Geoffroy; Helou, Nour El; Schaal, Karine; Quinquis, Laurent; Nassif, Hala; Tafflet, Muriel; Escolano, Sylvie; Hermine, Olivier; Toussaint, Jean-François

2010-01-01

Sex is a major factor influencing best performances and world records. Here the evolution of the difference between men and women's best performances is characterized through the analysis of 82 quantifiable events since the beginning of the Olympic era. For each event in swimming, athletics, track cycling, weightlifting and speed skating the gender gap is fitted to compare male and female records. It is also studied through the best performance of the top 10 performers in each gender for swimming and athletics. A stabilization of the gender gap in world records is observed after 1983, at a mean difference of 10.0% ± 2.94 between men and women for all events. The gender gap ranges from 5.5% (800-m freestyle, swimming) to 18.8% (long jump). The mean gap is 10.7% for running performances, 17.5% for jumps, 8.9% for swimming races, 7.0% for speed skating and 8.7% in cycling. The top ten performers' analysis reveals a similar gender gap trend with a stabilization in 1982 at 11.7%, despite the large growth in participation of women from eastern and western countries, that coincided with later- published evidence of state-institutionalized or individual doping. These results suggest that women will not run, jump, swim or ride as fast as men. Key pointsSex is a major factor influencing best performances and world records.A stabilization of the gender gap in world records is observed after 1983, at a mean difference of 10.0% ± 2.94 between men and women for all events.The gender gap ranges from 5.5% (800-m freestyle, swimming) to 36.8% (weight lifting).The top ten performers' analysis reveals a similar gender gap trend with a stabilization in 1982 at 11.7%.Results suggest that women will not run, jump, swim or ride as fast as men.

Women and Men in Sport Performance: The Gender Gap has not Evolved since 1983

PubMed Central

Thibault, Valérie; Guillaume, Marion; Berthelot, Geoffroy; Helou, Nour El; Schaal, Karine; Quinquis, Laurent; Nassif, Hala; Tafflet, Muriel; Escolano, Sylvie; Hermine, Olivier; Toussaint, Jean-François.

2010-01-01

Sex is a major factor influencing best performances and world records. Here the evolution of the difference between men and women’s best performances is characterized through the analysis of 82 quantifiable events since the beginning of the Olympic era. For each event in swimming, athletics, track cycling, weightlifting and speed skating the gender gap is fitted to compare male and female records. It is also studied through the best performance of the top 10 performers in each gender for swimming and athletics. A stabilization of the gender gap in world records is observed after 1983, at a mean difference of 10.0% ± 2.94 between men and women for all events. The gender gap ranges from 5.5% (800-m freestyle, swimming) to 18.8% (long jump). The mean gap is 10.7% for running performances, 17.5% for jumps, 8.9% for swimming races, 7.0% for speed skating and 8.7% in cycling. The top ten performers’ analysis reveals a similar gender gap trend with a stabilization in 1982 at 11.7%, despite the large growth in participation of women from eastern and western countries, that coincided with later- published evidence of state-institutionalized or individual doping. These results suggest that women will not run, jump, swim or ride as fast as men. Key points Sex is a major factor influencing best performances and world records. A stabilization of the gender gap in world records is observed after 1983, at a mean difference of 10.0% ± 2.94 between men and women for all events. The gender gap ranges from 5.5% (800-m freestyle, swimming) to 36.8% (weight lifting). The top ten performers’ analysis reveals a similar gender gap trend with a stabilization in 1982 at 11.7%. Results suggest that women will not run, jump, swim or ride as fast as men. PMID:24149688

Uniformitarianism and its Discontents: Microbial Evolution and Co-evolution of Life and Earth

NASA Astrophysics Data System (ADS)

Wing, B. A.

2016-12-01

For the first ≈4 billion years of Earth history, life was microscopic. There are ≈5x1030 bacteria and archaea on Earth today. Mean turnover times of natural microbial populations are days to millennia (10-2 to 103 years). Assuming that a similar-sized microbial biosphere has been maintained since ≈4 billion years ago, the number of microbes that have ever lived on Earth is awesome: >1037 to 1042. In broad brush, these numbers represent the individual microbial evolution experiments run by Nature. They are many, many orders of magnitude greater than the number of stars in the universe. Despite this numerical hurdle, the geological record is read with the assumption that microbes in the geological past were doing exactly what microbes do today. In this presentation, I will discuss evolutionary impacts on a critical microbial phentypic trait - sulfur isotope fractionation - that has played a critical role in our interpretations of the the evolution of the Earth system. The discussion will range from microbial evolution experiments to models of metabolic evolution, with an eye toward understanding the evolutionary weaknesses and strengths in our uniformiatrian world view.

Convergent evolution and parallelism in plant domestication revealed by an expanding archaeological record

PubMed Central

Fuller, Dorian Q; Denham, Tim; Arroyo-Kalin, Manuel; Lucas, Leilani; Stevens, Chris J.; Qin, Ling; Allaby, Robin G.; Purugganan, Michael D.

2014-01-01

Recent increases in archaeobotanical evidence offer insights into the processes of plant domestication and agricultural origins, which evolved in parallel in several world regions. Many different crop species underwent convergent evolution and acquired domestication syndrome traits. For a growing number of seed crop species, these traits can be quantified by proxy from archaeological evidence, providing measures of the rates of change during domestication. Among domestication traits, nonshattering cereal ears evolved more quickly in general than seed size. Nevertheless, most domestication traits show similarly slow rates of phenotypic change over several centuries to millennia, and these rates were similar across different regions of origin. Crops reproduced vegetatively, including tubers and many fruit trees, are less easily documented in terms of morphological domestication, but multiple lines of evidence outline some patterns in the development of vegecultural systems across the New World and Old World tropics. Pathways to plant domestication can also be compared in terms of the cultural and economic factors occurring at the start of the process. Whereas agricultural societies have tended to converge on higher population densities and sedentism, in some instances cultivation began among sedentary hunter–gatherers whereas more often it was initiated by mobile societies of hunter–gatherers or herder–gatherers. PMID:24753577

On the evolution of the Universe

NASA Astrophysics Data System (ADS)

Kondratenko, P. O.

2014-12-01

In this paper a model of creation and evolution of the universe in which the laws of physics are performed. The model implies that our Universe is a part of a Super-Universe as a separate layer in the fiber space, and the information communication exists between adjacent layers through the single point. During the formation of Super-Universe it was filled first a one-dimensional World of Field-time, then a two-dimensional (1+1) World was filled with energy and Planck's particles which carry the electric and magnetic charges. Completion of two-dimensional world filling leads to a "transfusion" of energy into the neighboring three-dimensional World which presents a world of known quarks which have the fractional electric charges, color charges, and spins. The next step is a "transfusion" of energy into the four-dimensional (3+1) World and the birth of the particles of this World. Evolution of this World has a completion by the brane creation of five-dimensional World. This evolution is accompanying by the birth of the entire set of stable and unstable heavy nuclei and atoms. A filling of each new layer at the fiber space does not bring the entropy into this space (i.e. cold and completely deterministic start of evolution). The proposed model supports the anthropic principle in the Universe.

On quantum effects in a theory of biological evolution.

PubMed

Martin-Delgado, M A

2012-01-01

We construct a descriptive toy model that considers quantum effects on biological evolution starting from Chaitin's classical framework. There are smart evolution scenarios in which a quantum world is as favorable as classical worlds for evolution to take place. However, in more natural scenarios, the rate of evolution depends on the degree of entanglement present in quantum organisms with respect to classical organisms. If the entanglement is maximal, classical evolution turns out to be more favorable.

On Quantum Effects in a Theory of Biological Evolution

PubMed Central

Martin-Delgado, M. A.

2012-01-01

We construct a descriptive toy model that considers quantum effects on biological evolution starting from Chaitin's classical framework. There are smart evolution scenarios in which a quantum world is as favorable as classical worlds for evolution to take place. However, in more natural scenarios, the rate of evolution depends on the degree of entanglement present in quantum organisms with respect to classical organisms. If the entanglement is maximal, classical evolution turns out to be more favorable. PMID:22413059

Mathematical analysis of running performance and world running records.

PubMed

Péronnet, F; Thibault, G

1989-07-01

The objective of this study was to develop an empirical model relating human running performance to some characteristics of metabolic energy-yielding processes using A, the capacity of anaerobic metabolism (J/kg); MAP, the maximal aerobic power (W/kg); and E, the reduction in peak aerobic power with the natural logarithm of race duration T, when T greater than TMAP = 420 s. Accordingly, the model developed describes the average power output PT (W/kg) sustained over any T as PT = [S/T(1 - e-T/k2)] + 1/T integral of T O [BMR + B(1 - e-t/k1)]dt where S = A and B = MAP - BMR (basal metabolic rate) when T less than TMAP; and S = A + [Af ln(T/TMAP)] and B = (MAP - BMR) + [E ln(T/TMAP)] when T greater than TMAP; k1 = 30 s and k2 = 20 s are time constants describing the kinetics of aerobic and anaerobic metabolism, respectively, at the beginning of exercise; f is a constant describing the reduction in the amount of energy provided from anaerobic metabolism with increasing T; and t is the time from the onset of the race. This model accurately estimates actual power outputs sustained over a wide range of events, e.g., average absolute error between actual and estimated T for men's 1987 world records from 60 m to the marathon = 0.73%. In addition, satisfactory estimations of the metabolic characteristics of world-class male runners were made as follows: A = 1,658 J/kg; MAP = 83.5 ml O2.kg-1.min-1; 83.5% MAP sustained over the marathon distance. Application of the model to analysis of the evolution of A, MAP, and E, and of the progression of men's and women's world records over the years, is presented.

Relaxed evolution in the tyrosine aminotransferase gene tat in old world fruit bats (Chiroptera: Pteropodidae).

PubMed

Shen, Bin; Fang, Tao; Yang, Tianxiao; Jones, Gareth; Irwin, David M; Zhang, Shuyi

2014-01-01

Frugivorous and nectarivorous bats fuel their metabolism mostly by using carbohydrates and allocate the restricted amounts of ingested proteins mainly for anabolic protein syntheses rather than for catabolic energy production. Thus, it is possible that genes involved in protein (amino acid) catabolism may have undergone relaxed evolution in these fruit- and nectar-eating bats. The tyrosine aminotransferase (TAT, encoded by the Tat gene) is the rate-limiting enzyme in the tyrosine catabolic pathway. To test whether the Tat gene has undergone relaxed evolution in the fruit- and nectar-eating bats, we obtained the Tat coding region from 20 bat species including four Old World fruit bats (Pteropodidae) and two New World fruit bats (Phyllostomidae). Phylogenetic reconstructions revealed a gene tree in which all echolocating bats (including the New World fruit bats) formed a monophyletic group. The phylogenetic conflict appears to stem from accelerated TAT protein sequence evolution in the Old World fruit bats. Our molecular evolutionary analyses confirmed a change in the selection pressure acting on Tat, which was likely caused by a relaxation of the evolutionary constraints on the Tat gene in the Old World fruit bats. Hepatic TAT activity assays showed that TAT activities in species of the Old World fruit bats are significantly lower than those of insectivorous bats and omnivorous mice, which was not caused by a change in TAT protein levels in the liver. Our study provides unambiguous evidence that the Tat gene has undergone relaxed evolution in the Old World fruit bats in response to changes in their metabolism due to the evolution of their special diet.

A Watched Ocean World Never Boils: Inspecting the Geochemical Impact on Ocean Worlds from Their Thermal Evolution

NASA Astrophysics Data System (ADS)

Spiers, E. M.; Schmidt, B. E.

2018-05-01

I aim to acquire better understanding of coupled thermal evolution and geochemical fluxes of an ocean world through a box model. A box model divides the system into plainer elements with realistically-solvable, dynamic equations.

Mirror Neurons in a New World Monkey, Common Marmoset

PubMed Central

Suzuki, Wataru; Banno, Taku; Miyakawa, Naohisa; Abe, Hiroshi; Goda, Naokazu; Ichinohe, Noritaka

2015-01-01

Mirror neurons respond when executing a motor act and when observing others' similar act. So far, mirror neurons have been found only in macaques, humans, and songbirds. To investigate the degree of phylogenetic specialization of mirror neurons during the course of their evolution, we determined whether mirror neurons with similar properties to macaques occur in a New World monkey, the common marmoset (Callithrix jacchus). The ventral premotor cortex (PMv), where mirror neurons have been reported in macaques, is difficult to identify in marmosets, since no sulcal landmarks exist in the frontal cortex. We addressed this problem using “in vivo” connection imaging methods. That is, we first identified cells responsive to others' grasping action in a clear landmark, the superior temporal sulcus (STS), under anesthesia, and injected fluorescent tracers into the region. By fluorescence stereomicroscopy, we identified clusters of labeled cells in the ventrolateral frontal cortex, which were confirmed to be within the ventrolateral frontal cortex including PMv after sacrifice. We next implanted electrodes into the ventrolateral frontal cortex and STS and recorded single/multi-units under an awake condition. As a result, we found neurons in the ventrolateral frontal cortex with characteristic “mirror” properties quite similar to those in macaques. This finding suggests that mirror neurons occur in a common ancestor of New and Old World monkeys and its common properties are preserved during the course of primate evolution. PMID:26696817

"Small World" architecture in brain connectivity and hippocampal volume in Alzheimer's disease: a study via graph theory from EEG data.

PubMed

Vecchio, Fabrizio; Miraglia, Francesca; Piludu, Francesca; Granata, Giuseppe; Romanello, Roberto; Caulo, Massimo; Onofrj, Valeria; Bramanti, Placido; Colosimo, Cesare; Rossini, Paolo Maria

2017-04-01

Brain imaging plays an important role in the study of Alzheimer's disease (AD), where atrophy has been found to occur in the hippocampal formation during the very early disease stages and to progress in parallel with the disease's evolution. The aim of the present study was to evaluate a possible correlation between "Small World" characteristics of the brain connectivity architecture-as extracted from EEG recordings-and hippocampal volume in AD patients. A dataset of 144 subjects, including 110 AD (MMSE 21.3) and 34 healthy Nold (MMSE 29.8) individuals, was evaluated. Weighted and undirected networks were built by the eLORETA solutions of the cortical sources' activities moving from EEG recordings. The evaluation of the hippocampal volume was carried out on a subgroup of 60 AD patients who received a high-resolution T1-weighted sequence and underwent processing for surface-based cortex reconstruction and volumetric segmentation using the Freesurfer image analysis software. Results showed that, quantitatively, more correlation was observed in the right hemisphere, but the same trend was seen in both hemispheres. Alpha band connectivity was negatively correlated, while slow (delta) and fast-frequency (beta, gamma) bands positively correlated with hippocampal volume. Namely, the larger the hippocampal volume, the lower the alpha and the higher the delta, beta, and gamma Small World characteristics of connectivity. Accordingly, the Small World connectivity pattern could represent a functional counterpart of structural hippocampal atrophying and related-network disconnection.

Phosphoenolpyruvate carboxykinase 1 gene (Pck1) displays parallel evolution between Old World and New World fruit bats.

PubMed

Zhu, Lei; Yin, Qiuyuan; Irwin, David M; Zhang, Shuyi

2015-01-01

Bats are an ideal mammalian group for exploring adaptations to fasting due to their large variety of diets and because fasting is a regular part of their life cycle. Mammals fed on a carbohydrate-rich diet experience a rapid decrease in blood glucose levels during a fast, thus, the development of mechanisms to resist the consequences of regular fasts, experienced on a daily basis, must have been crucial in the evolution of frugivorous bats. Phosphoenolpyruvate carboxykinase 1 (PEPCK1, encoded by the Pck1 gene) is the rate-limiting enzyme in gluconeogenesis and is largely responsible for the maintenance of glucose homeostasis during fasting in fruit-eating bats. To test whether Pck1 has experienced adaptive evolution in frugivorous bats, we obtained Pck1 coding sequence from 20 species of bats, including five Old World fruit bats (OWFBs) (Pteropodidae) and two New World fruit bats (NWFBs) (Phyllostomidae). Our molecular evolutionary analyses of these sequences revealed that Pck1 was under purifying selection in both Old World and New World fruit bats with no evidence of positive selection detected in either ancestral branch leading to fruit bats. Interestingly, however, six specific amino acid substitutions were detected on the ancestral lineage of OWFBs. In addition, we found considerable evidence for parallel evolution, at the amino acid level, between the PEPCK1 sequences of Old World fruit bats and New World fruit bats. Test for parallel evolution showed that four parallel substitutions (Q276R, R503H, I558V and Q593R) were driven by natural selection. Our study provides evidence that Pck1 underwent parallel evolution between Old World and New World fruit bats, two lineages of mammals that feed on a carbohydrate-rich diet and experience regular periods of fasting as part of their life cycle.

Phosphoenolpyruvate Carboxykinase 1 Gene (Pck1) Displays Parallel Evolution between Old World and New World Fruit Bats

PubMed Central

Irwin, David M.; Zhang, Shuyi

2015-01-01

Bats are an ideal mammalian group for exploring adaptations to fasting due to their large variety of diets and because fasting is a regular part of their life cycle. Mammals fed on a carbohydrate-rich diet experience a rapid decrease in blood glucose levels during a fast, thus, the development of mechanisms to resist the consequences of regular fasts, experienced on a daily basis, must have been crucial in the evolution of frugivorous bats. Phosphoenolpyruvate carboxykinase 1 (PEPCK1, encoded by the Pck1 gene) is the rate-limiting enzyme in gluconeogenesis and is largely responsible for the maintenance of glucose homeostasis during fasting in fruit-eating bats. To test whether Pck1 has experienced adaptive evolution in frugivorous bats, we obtained Pck1 coding sequence from 20 species of bats, including five Old World fruit bats (OWFBs) (Pteropodidae) and two New World fruit bats (NWFBs) (Phyllostomidae). Our molecular evolutionary analyses of these sequences revealed that Pck1 was under purifying selection in both Old World and New World fruit bats with no evidence of positive selection detected in either ancestral branch leading to fruit bats. Interestingly, however, six specific amino acid substitutions were detected on the ancestral lineage of OWFBs. In addition, we found considerable evidence for parallel evolution, at the amino acid level, between the PEPCK1 sequences of Old World fruit bats and New World fruit bats. Test for parallel evolution showed that four parallel substitutions (Q276R, R503H, I558V and Q593R) were driven by natural selection. Our study provides evidence that Pck1 underwent parallel evolution between Old World and New World fruit bats, two lineages of mammals that feed on a carbohydrate-rich diet and experience regular periods of fasting as part of their life cycle. PMID:25807515

Oligocene primates from China reveal divergence between African and Asian primate evolution.

PubMed

Ni, Xijun; Li, Qiang; Li, Lüzhou; Beard, K Christopher

2016-05-06

Profound environmental and faunal changes are associated with climatic deterioration during the Eocene-Oligocene transition (EOT) roughly 34 million years ago. Reconstructing how Asian primates responded to the EOT has been hindered by a sparse record of Oligocene primates on that continent. Here, we report the discovery of a diverse primate fauna from the early Oligocene of southern China. In marked contrast to Afro-Arabian Oligocene primate faunas, this Asian fauna is dominated by strepsirhines. There appears to be a strong break between Paleogene and Neogene Asian anthropoid assemblages. Asian and Afro-Arabian primate faunas responded differently to EOT climatic deterioration, indicating that the EOT functioned as a critical evolutionary filter constraining the subsequent course of primate evolution across the Old World. Copyright © 2016, American Association for the Advancement of Science.

SWS2 visual pigment evolution as a test of historically contingent patterns of plumage color evolution in warblers.

PubMed

Bloch, Natasha I; Morrow, James M; Chang, Belinda S W; Price, Trevor D

2015-02-01

Distantly related clades that occupy similar environments may differ due to the lasting imprint of their ancestors-historical contingency. The New World warblers (Parulidae) and Old World warblers (Phylloscopidae) are ecologically similar clades that differ strikingly in plumage coloration. We studied genetic and functional evolution of the short-wavelength-sensitive visual pigments (SWS2 and SWS1) to ask if altered color perception could contribute to the plumage color differences between clades. We show SWS2 is short-wavelength shifted in birds that occupy open environments, such as finches, compared to those in closed environments, including warblers. Phylogenetic reconstructions indicate New World warblers were derived from a finch-like form that colonized from the Old World 15-20 Ma. During this process, the SWS2 gene accumulated six substitutions in branches leading to New World warblers, inviting the hypothesis that passage through a finch-like ancestor resulted in SWS2 evolution. In fact, we show spectral tuning remained similar across warblers as well as the finch ancestor. Results reject the hypothesis of historical contingency based on opsin spectral tuning, but point to evolution of other aspects of visual pigment function. Using the approach outlined here, historical contingency becomes a generally testable theory in systems where genotype and phenotype can be connected. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

Relaxed Evolution in the Tyrosine Aminotransferase Gene Tat in Old World Fruit Bats (Chiroptera: Pteropodidae)

PubMed Central

Shen, Bin; Fang, Tao; Yang, Tianxiao; Jones, Gareth; Irwin, David M.; Zhang, Shuyi

2014-01-01

Frugivorous and nectarivorous bats fuel their metabolism mostly by using carbohydrates and allocate the restricted amounts of ingested proteins mainly for anabolic protein syntheses rather than for catabolic energy production. Thus, it is possible that genes involved in protein (amino acid) catabolism may have undergone relaxed evolution in these fruit- and nectar-eating bats. The tyrosine aminotransferase (TAT, encoded by the Tat gene) is the rate-limiting enzyme in the tyrosine catabolic pathway. To test whether the Tat gene has undergone relaxed evolution in the fruit- and nectar-eating bats, we obtained the Tat coding region from 20 bat species including four Old World fruit bats (Pteropodidae) and two New World fruit bats (Phyllostomidae). Phylogenetic reconstructions revealed a gene tree in which all echolocating bats (including the New World fruit bats) formed a monophyletic group. The phylogenetic conflict appears to stem from accelerated TAT protein sequence evolution in the Old World fruit bats. Our molecular evolutionary analyses confirmed a change in the selection pressure acting on Tat, which was likely caused by a relaxation of the evolutionary constraints on the Tat gene in the Old World fruit bats. Hepatic TAT activity assays showed that TAT activities in species of the Old World fruit bats are significantly lower than those of insectivorous bats and omnivorous mice, which was not caused by a change in TAT protein levels in the liver. Our study provides unambiguous evidence that the Tat gene has undergone relaxed evolution in the Old World fruit bats in response to changes in their metabolism due to the evolution of their special diet. PMID:24824435

Galapagos III World Evolution Summit: why evolution matters

PubMed Central

Paz-y-Miño-C, Guillermo; Espinosa, Avelina

2016-01-01

There is no place on Earth like the Galapagos Islands and no better destination to discuss the reality of evolution. Under the theme ‘Why Does Evolution Matter’, the University San Francisco of Quito (USFQ), Ecuador, and its Galapagos Institute for the Arts and Sciences (GAIAS), organized the III World Evolution Summit in San Cristóbal Island. The 200-attendee meeting took place on 1 to 5 June 2013; it included 12 keynote speakers, 20 oral presentations by international scholars, and 31 posters by faculty, postdocs, and graduate and undergraduate students. The Summit encompassed five sessions: evolution and society, pre-cellular evolution and the RNA world, behavior and environment, genome, and microbes and diseases. USFQ and GAIAS launched officially the Lynn Margulis Center for Evolutionary Biology and showcased the Galapagos Science Center, in San Cristóbal, an impressive research facility conceptualized in partnership with the University of North Carolina at Chapel Hill, USA. USFQ and GAIAS excelled at managing the conference with exceptional vision and at highlighting the relevance of Galapagos in the history of modern evolutionary thinking; Charles Darwin’s visit to this volcanic archipelago in 1835 unfolded unprecedented scientific interest in what today is a matchless World Heritage. PMID:26925190

The Morphology and Sedimentology of Fluvial Megascours

NASA Astrophysics Data System (ADS)

Bull, J. M.; Vardy, M. E.; Sambrook Smith, G.; Best, J.; Dixon, S. J.; Goodbred, S. L., Jr.

2015-12-01

Scour zones in the World's largest rivers, or so-called "megascours", are extensive and dynamic features that are currently poorly understood in terms of their morphology and kinematics. Such scours can erode c. 50-60 metres below the water surface, extend laterally for 100s metres to kilometres, and may migrate kilometres in a single year. Understanding the evolution of such scour zones has important implications for improved flood and bank erosion prediction, better infrastructure planning (e.g. bridges, embankments), and differentiating between autocyclic and allocyclic erosion in the geological record (e.g. sequence stratigraphic applications). Here, we present results from two field seasons using geophysical techniques (high-resolution multibeam bathymetry and seismic reflection data using Chirp and Boomer sources) to study six scour zones in the Ganges-Jamuna-Padma-Meghna river system of Bangladesh. These scours include some of the World's largest confluences, as well as smaller distributaries, and those with varying levels of tidal influence. Seismic data from repeat surveys permit an accurate characterization of short-term scour evolution and associated deposits across two monsoonal flood peaks. Meanwhile, the bathymetric data reveals widespread deep scours (30-40 m) even in small, downstream distributary tidal channels, illustrating that megascours are present all the way to the subaerial delta fringe. Bathymetric analysis also shows a complex relationship between these scours and bedform distribution and orientation. This suggests the need for a new scaling for sand dune dimensions at such sites, and the need for substantial revisions to current ideas on the use of dune-scale cross-stratification to infer palaeoflow depths in the ancient sedimentary record.

Failing to protect humanitarian workers: lessons from Britain and Voluntary Aid Detachments in the Second World War.

PubMed

Verma, Amol A

2017-09-01

This paper draws on official records of international and British organizations, newspaper reports, and volunteer memoirs to study the failure to protect humanitarian workers in the Second World War. The Second World War saw a significant expansion in the use of air warfare and flying missiles and these technological advances posed a grave threat to civilians and humanitarian workers. In this context, the International Committee of the Red Cross advocated unsuccessfully to restrict air warfare and create safe hospital zones. The British Government grappled with the tension between military and humanitarian objectives in setting its bombardment policy. Ultimately, humanitarian principles were neglected in pursuit of strategic aims, which endangered civilians and left humanitarian workers particularly vulnerable. British Voluntary Aid Detachment nurses experienced more than six-fold greater fatality rates than civil defence workers and the general population. The lessons from failures to protect humanitarian workers in the face of evolutions in warfare remain profoundly relevant.

Are there limits to swimming world records?

PubMed

Nevill, A M; Whyte, G P; Holder, R L; Peyrebrune, M

2007-12-01

The purpose of this article was to investigate whether swimming world records are beginning to plateau and whether the inequality between men and women's swimming performances is narrowing, similar to that observed in running world records. A flattened "S-shaped curve" logistic curve is fitted to 100-m, 200-m, and 400-m front-crawl world-record swimming speeds for men and women from 1 May 1957 to the present time, using the non-linear least-squares regression. The inequality between men and women's world records is also assessed using the ratio, Women's/Men's world record speeds. The results confirm that men and women's front-crawl swimming world-record speeds are plateauing and the ratio between women's and men's world records has remained stable at approximately 0.9. In conclusion, the logistic curves provide evidence that swimming world-record speeds experienced a period of "accelerated" growth/improvements during the 1960 - 1970s, but are now beginning to plateau. The period of acceleration corresponded with numerous advances in science and technology but also coincided with the anecdotal evidence for institutionalised doping. Also noteworthy, however, is the remarkably consistency in the women's/men's world record ratio, circa 0.9, similar to those observed in middle and long distance running performances. These finding supports the notion that a 10 % gender inequality exists for both swimming and running.

Parallel evolution of the glycogen synthase 1 (muscle) gene Gys1 between Old World and New World fruit bats (Order: Chiroptera).

PubMed

Fang, Lu; Shen, Bin; Irwin, David M; Zhang, Shuyi

2014-10-01

Glycogen synthase, which catalyzes the synthesis of glycogen, is especially important for Old World (Pteropodidae) and New World (Phyllostomidae) fruit bats that ingest high-carbohydrate diets. Glycogen synthase 1, encoded by the Gys1 gene, is the glycogen synthase isozyme that functions in muscles. To determine whether Gys1 has undergone adaptive evolution in bats with carbohydrate-rich diets, in comparison to insect-eating sister bat taxa, we sequenced the coding region of the Gys1 gene from 10 species of bats, including two Old World fruit bats (Pteropodidae) and a New World fruit bat (Phyllostomidae). Our results show no evidence for positive selection in the Gys1 coding sequence on the ancestral Old World and the New World Artibeus lituratus branches. Tests for convergent evolution indicated convergence of the sequences and one parallel amino acid substitution (T395A) was detected on these branches, which was likely driven by natural selection.

Evolutionary dynamics of Rh2 opsins in birds demonstrate an episode of accelerated evolution in the New World warblers (Setophaga)

PubMed Central

Price, Trevor D.

2015-01-01

Low rates of sequence evolution associated with purifying selection can be interrupted by episodic changes in selective regimes. Visual pigments are a unique system in which we can investigate the functional consequences of genetic changes, therefore connecting genotype to phenotype in the context of natural and sexual selection pressures. We study the RH2 and RH1 visual pigments (opsins) across 22 bird species belonging to two ecologically convergent clades, the New World warblers (Parulidae) and Old World warblers (Phylloscopidae), and evaluate rates of evolution in these clades along with data from 21 additional species. We demonstrate generally slow evolution of these opsins: both Rh1 and Rh2 are highly conserved across Old World and New World warblers. However, Rh2 underwent a burst of evolution within the New World genus Setophaga, where it accumulated substitutions at 6 amino acid sites across the species we studied. Evolutionary analyses revealed a significant increase in dN/dS in Setophaga, implying relatively strong selective pressures to overcome long-standing purifying selection. We studied the effects of each substitution on spectral tuning and found they do not cause large spectral shifts. Thus substitutions may reflect other aspects of opsin function, such as those affecting photosensitivity and/or dark-light adaptation. Although it is unclear what these alterations mean for color perception, we suggest that rapid evolution is linked to sexual selection, given the exceptional plumage colour diversification in Setophaga. PMID:25827331

Student world view as a framework for learning genetics and evolution in high school biology

NASA Astrophysics Data System (ADS)

McCoy, Roger Wesley

Statement of the problem. Few studies in biology education have examined the underlying presuppositions which guide thinking and concept learning in adolescents. The purpose of this study was to describe and understand the biological world views of a variety of high school students before they take biology courses. Specifically, the study examined student world views in the domains of Classification, Relationship and Causation related to the concepts of heredity, evolution and biotechnology. The following served as guiding questions: (1) What are the personal world views of high school students entering biology classes, related to the domain of Classification, Relationship and Causality? (2) How do these student world views confound or enhance the learning of basic concepts in genetics and evolution? Methods. An interpretive method was chosen for this study. The six student participants were ninth graders and represented a wide range of world view backgrounds. A series of three interviews was conducted with each participant, with a focus group used for triangulation of data. The constant comparative method was used to categorize the data and facilitate the search for meaningful patterns. The analysis included a thick description of each student's personal views of classification, evolution and the appropriate use of biotechnology. Results. The study demonstrates that world view is the basis upon which students build knowledge in biology. The logic of their everyday thinking may not match that of scientists. The words they use are sometimes inconsistent with scientific terminology. This study provides evidence that students voice different opinions depending on the social situation, since they are strongly influenced by peers. Students classify animals based on behaviors. They largely believe that the natural world is unpredictable, and that humans are not really part of that world. Half are unlikely to accept the evolution of humans, but may accept it in other species. Their views on causation of evolution vary widely, focusing on intentional changes made by animals. Students who hold world views which differ from scientific world views may become marginalized unless differences in world view are addressed. Researchers and teachers must be mindful of social pressures which cause students to reject certain ideas which may appear to be in opposition to their existing world view.

Progressive Climate Change on Titan: Implications for Habitability

NASA Technical Reports Server (NTRS)

Moore, J. M.; A. D. Howard

2014-01-01

Titan's landscape is profoundly shaped by its atmosphere and comparable in magnitude perhaps with only the Earth and Mars amongst the worlds of the Solar System. Like the Earth, climate dictates the intensity and relative roles of fluvial and aeolian activity from place to place and over geologic time. Thus Titan's landscape is the record of climate change. We have investigated three broad classes of Titan climate evolution hypotheses (Steady State, Progressive, and Cyclic), regulated by the role, sources, and availability of methane. We favor the Progressive hypotheses, which we will outline here, then discuss their implication for habitability.

Visual responses of ganglion cells of a New-World primate, the capuchin monkey, Cebus apella.

PubMed

Lee, B B; Silveira, L C; Yamada, E S; Hunt, D M; Kremers, J; Martin, P R; Troy, J B; da Silva-Filho, M

2000-11-01

1. The genetic basis of colour vision in New-World primates differs from that in humans and other Old-World primates. Most New-World primate species show a polymorphism; all males are dichromats and most females trichromats. 2. In the retina of Old-World primates such as the macaque, the physiological correlates of trichromacy are well established. Comparison of the retinae in New- and Old-World species may help constrain hypotheses as to the evolution of colour vision and the pathways associated with it. 3. Ganglion cell behaviour was recorded from trichromatic and dichromatic members of a New-World species (the capuchin monkey, Cebus apella) and compared with macaque data. Despite some differences in quantitative detail (such as a temporal response extended to higher frequencies), results from trichromatic animals strongly resembled those from the macaque. 4. In particular, cells of the parvocellular (PC) pathway showed characteristic frequency-dependent changes in responsivity to luminance and chromatic modulation, cells of the magnocellular (MC) pathway showed frequency-doubled responses to chromatic modulation, and the surround of MC cells received a chromatic input revealed on changing the phase of heterochromatically modulated lights. 5. Ganglion cells of dichromats were colour-blind versions of those of trichromats. 6. This strong physiological homology is consistent with a common origin of trichromacy in New- and Old-World monkeys; in the New-World primate the presence of two pigments in the middle-to-long wavelength range permits full expression of the retinal mechanisms of trichromatic vision.

The Cosmic Zoo: The (Near) Inevitability of the Evolution of Complex, Macroscopic Life

PubMed Central

Bains, William; Schulze-Makuch, Dirk

2016-01-01

Life on Earth provides a unique biological record from single-cell microbes to technologically intelligent life forms. Our evolution is marked by several major steps or innovations along a path of increasing complexity from microbes to space-faring humans. Here we identify various major key innovations, and use an analytical toolset consisting of a set of models to analyse how likely each key innovation is to occur. Our conclusion is that once the origin of life is accomplished, most of the key innovations can occur rather readily. The conclusion for other worlds is that if the origin of life can occur rather easily, we should live in a cosmic zoo, as the innovations necessary to lead to complex life will occur with high probability given sufficient time and habitat. On the other hand, if the origin of life is rare, then we might live in a rather empty universe. PMID:27376334

Five scientists at Johns Hopkins in the modern evolution of neuroscience.

PubMed

Harrison, T S

2000-08-01

Neuroscience's evolution at Johns Hopkins, from neurophysiology to the new field of neurobiology, though unplanned, was rapid and important. Beginning in 1933 when Philip Bard became professor of physiology at Johns Hopkins, members of his department concentrated initially on neuroanatomical control of placing reactions and sexual activity. Vernon Mountcastle, extending available techniques, discovered vertical somato-sensory columns in the 1950's. Stephen Kuffler, who arrived at Hopkins in 1947, was a pioneer in single unit microelectrode recording techniques. He soon attracted scientists from all over the world to his laboratory. Among them, Torsten Wiesel and David Hubel discovered vertical neuronal columns in the visual cortex. During several decades at Johns Hopkins, these five scientists set extremely high scientific standards and established a climate of inquiry in which ideas were shared and young scientists encouraged. They contributed significantly to the emerging discipline of neuroscience.

Geobiotropy: The Evolution of Rocks in Symbiosis with Prebiotic Chemistry

NASA Astrophysics Data System (ADS)

Bassez, M. P.

2017-07-01

In their interaction with water, minerals inside rocks transform with production of elements and small molecules which intervene in prebiotic syntheses. This chemical evolution between the world of rocks and the world of life is called geobiotropy.

Glycomics: revealing the dynamic ecology and evolution of sugar molecules.

PubMed

Springer, Stevan A; Gagneux, Pascal

2016-03-01

Sugars are the most functionally and structurally diverse molecules in the biological world. Glycan structures range from tiny single monosaccharide units to giant chains thousands of units long. Some glycans are branched, their monosaccharides linked together in many different combinations and orientations. Some exist as solitary molecules; others are conjugated to proteins and lipids and alter their collective functional properties. In addition to structural and storage roles, glycan molecules participate in and actively regulate physiological and developmental processes. Glycans also mediate cellular interactions within and between individuals. Their roles in ecology and evolution are pivotal, but not well studied because glycan biochemistry requires different methods than standard molecular biology practice. The properties of glycans are in some ways convenient, and in others challenging. Glycans vary on organismal timescales, and in direct response to physiological and ecological conditions. Their mature structures are physical records of both genetic and environmental influences during maturation. We describe the scope of natural glycan variation and discuss how studying glycans will allow researchers to further integrate the fields of ecology and evolution. Copyright © 2015 Elsevier B.V. All rights reserved.

Fossil evidence for the early ant evolution

NASA Astrophysics Data System (ADS)

Perrichot, Vincent; Lacau, Sébastien; Néraudeau, Didier; Nel, André

2008-02-01

Ants are one of the most studied insects in the world; and the literature devoted to their origin and evolution, systematics, ecology, or interactions with plants, fungi and other organisms is prolific. However, no consensus yet exists on the age estimate of the first Formicidae or on the origin of their eusociality. We review the fossil and biogeographical record of all known Cretaceous ants. We discuss the possible origin of the Formicidae with emphasis on the most primitive subfamily Sphecomyrminae according to its distribution and the Early Cretaceous palaeogeography. And we review the evidence of true castes and eusociality of the early ants regarding their morphological features and their manner of preservation in amber. The mid-Cretaceous amber forest from south-western France where some of the oldest known ants lived, corresponded to a moist tropical forest close to the shore with a dominance of gymnosperm trees but where angiosperms (flowering plants) were already diversified. This palaeoenvironmental reconstruction supports an initial radiation of ants in forest ground litter coincident with the rise of angiosperms, as recently proposed as an ecological explanation for their origin and successful evolution.

Different evolutionary pathways underlie the morphology of wrist bones in hominoids

PubMed Central

2013-01-01

Background The hominoid wrist has been a focus of numerous morphological analyses that aim to better understand long-standing questions about the evolution of human and hominoid hand use. However, these same analyses also suggest various scenarios of complex and mosaic patterns of morphological evolution within the wrist and potentially multiple instances of homoplasy that would benefit from require formal analysis within a phylogenetic context. We identify morphological features that principally characterize primate – and, in particular, hominoid (apes, including humans) - wrist evolution and reveal the rate, process and evolutionary timing of patterns of morphological change on individual branches of the primate tree of life. Linear morphological variables of five wrist bones – the scaphoid, lunate, triquetrum, capitate and hamate – are analyzed in a diverse sample of extant hominoids (12 species, 332 specimens), Old World (8 species, 43 specimens) and New World (4 species, 26 specimens) monkeys, fossil Miocene apes (8 species, 20 specimens) and Plio-Pleistocene hominins (8 species, 18 specimens). Result Results reveal a combination of parallel and synapomorphic morphology within haplorrhines, and especially within hominoids, across individual wrist bones. Similar morphology of some wrist bones reflects locomotor behaviour shared between clades (scaphoid, triquetrum and capitate) while others (lunate and hamate) indicate clade-specific synapomorphic morphology. Overall, hominoids show increased variation in wrist bone morphology compared with other primate clades, supporting previous analyses, and demonstrate several occurrences of parallel evolution, particularly between orangutans and hylobatids, and among hominines (extant African apes, humans and fossil hominins). Conclusions Our analyses indicate that different evolutionary processes can underlie the evolution of a single anatomical unit (the wrist) to produce diversity in functional and morphological adaptations across individual wrist bones. These results exemplify a degree of evolutionary and functional independence across different wrist bones, the potential evolvability of skeletal morphology, and help to contextualize the postcranial mosaicism observed in the hominin fossil record. PMID:24148262

NREL Achieves World Record Performance For Thin Film Solar Cell Technology

Science.gov Websites

World Record Performance For Thin Film Solar Cell Technology Golden, Colo., May 10, 1996 world record in the performance of an advanced solar cell technology designed to have a major impact on the cost of electricity from the sun. NREL established a new world record "sunlight-to

The fossil record of evolution: Data on diversification and extinction

NASA Technical Reports Server (NTRS)

Sepkoski, J. J., Jr.

1991-01-01

Understanding of the evolution of complex life, and of the roles that changing terrestrial and extraterrestrial environments played in life's history, is dependent upon synthetic knowledge of the fossil record. Paleontologists have been describing fossils for more that two centuries. However, much of this information is dispersed in monographs and journal articles published throughout the world. Over the past several years, this literature was surveyed, and a data base on times of origination and extinction of fossil genera was compiled. The data base, which now holds approximately 32,000 genera, covers all taxonomic groups of marine animals, incorporates the most recent taxonomic assignments, and uses a detailed global time framework that can resolve originations and extinctions to intervals averaging three million years in duration. These data can be used to compile patterns of global biodiversity, measure rates of taxic evolution, and test hypotheses concerning adaptive radiations, mass extinctions, etc. Thus far, considerable effort was devoted to using the data to test the hypothesis of periodicity of mass extinction. Rates of extinction measured from the data base have also been used to calibrate models of evolutionary radiations in marine environments. It was observed that new groups, or clades of animals (i.e., orders and classes) tend to reach appreciable diversity first in nearshore environments and then to radiate in more offshore environments; during decline, these clades may disappear from the nearshore while persisting in offshore, deep water habitats. These observations have led to suggestions that there is something special about stressful or perturbed environments that promotes the evolution of novel kinds of animals that can rapidly replace their predecessors. The numerical model that is being investigated to study this phenomenon treats environments along onshore-offshore gradients as if they were discrete habitats. Other aspects of this investigation are presented.

Acquiring Marine Data in the Canada Basin, Arctic Ocean

NASA Astrophysics Data System (ADS)

Hutchinson, Deborah R.; Jackson, H. Ruth; Shimeld, John W.; Chapman, C. Borden; Childs, Jonathan R.; Funck, Thomas; Rowland, Robert W.

2009-06-01

Despite the record minimum ice extent in the Arctic Ocean for the past 2 years, collecting geophysical data with towed sensors in ice-covered regions continues to pose enormous challenges. Significant parts of the Canada Basin in the western Arctic Ocean have remained largely unmapped because thick multiyear ice has limited access even by research vessels strengthened against ice [Jackson et al., 1990]. Because of the resulting paucity of data, the western Arctic Ocean is one of the few areas of ocean in the world where major controversies still exist with respect to its origin and tectonic evolution [Grantz et al., 1990; Lawver and Scotese, 1990; Lane, 1997; Miller et al., 2006]. This article describes the logistical challenges and initial data sets from geophysical seismic reflection, seismic refraction, and hydrographic surveys in the Canada Basin conducted by scientists with U.S. and Canadian government agencies (Figure 1a) to fulfill the requirements of the United Nations Convention on the Law of the Sea to determine sediment thickness, geological origin, and basin evolution in this unexplored part of the world. Some of these data were collected using a single ship, but the heaviest ice conditions necessitated using two icebreakers, similar to other recent Arctic surveys [e.g., Jokat, 2003].

A Missing Link in the Evolution of the Cumulative Recorder

ERIC Educational Resources Information Center

Asano, Toshio; Lattal, Kennon A.

2012-01-01

A recently recovered cumulative recorder provides a missing link in the evolution of the cumulative recorder from a modified kymograph to a reliably operating, scientifically and commercially successful instrument. The recorder, the only physical evidence of such an early precommercial cumulative recorder yet found, was sent to Keio University in…

Modeling Global Spatial-Temporal Evolution of Society: Hyperbolic Growth and Historical Cycles

NASA Astrophysics Data System (ADS)

Kurkina, E. S.

2011-09-01

The global historical processes are under consideration; and laws of global evolution of the world community are studied. The world community is considered as a united complex self-developing and self-organizing system. It supposed that the main driving force of social-economical evolution was the positive feedback between the population size and the level of technological development, which was a cause of growth in blow-up regime both of population and of global economic indexes. The study is supported by the results of mathematical modeling founded on a nonlinear heat equation with a source. Every social-economical epoch characterizes by own specific spatial distributed structures. So the global dynamics of world community during the whole history is investigated throughout the prism of the developing of spatial-temporal structures. The model parameters have been chosen so that 1) total population follows stable hyperbolic growth, consistently with the demographic data; 2) the evolution of the World-System goes through 11 stages corresponding to the main historical epochs.

A modern regional geological analysis of Venezuela - lessons from a major new world oil province on exploration in mature areas

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

Daly, M.; Audemard, F.; Valdes, G.

1993-09-01

Venezuela has produced some 44 billion bbl of oil since the early part of the century. As such, it represents one of the world's major oil producers and a mature petroleum province. However, major tracts of Venezuela's sedimentary basins remain underexplored and large discoveries are still being made in new and old reservoir systems. A regional geological analysis of Venezuela, focusing on basin evolution and sequence stratigraphy and incorporating data from the three national oil companies, is presented. The analysis presents a regionally consistent tectonostratigraphic model capable of explaining the evolution of the Mesozoic and Cenozoic basins of Venezuela andmore » placing the major reservoir facies in their regional tectonic and sequence stratigraphic context. Four regional cross sections describe the stratigraphic and structural model. The model recognizes a Jurassic rifting event and inversion, succeeded by an Early Cretaceous passive margin. In western Venezuela, the Early Cretaceous passive subsidence is enhanced locally by extension related to the Colombian active margin. Venezuela experienced a major change in the Campanian with the initial collision of the Caribbean arc, recorded by foreland structuring and widespread stratigraphic changes. From the Campanian onward, the tectonostratigraphic evolution can be modeled in terms of a progressive southeast-directed arc-continent collision and the migration of the associated foredeep and rift basins. Within the tectonic framework, the major sequence stratigraphic units are identified and the reservoir distribution interpreted. This model provides a strong predictive tool to extrapolate reservoir systems into Venezuela's underexplored areas and to readdress its traditional areas.« less

A quantitative philology of introspection

PubMed Central

Diuk, Carlos G.; Slezak, D. Fernandez; Raskovsky, I.; Sigman, M.; Cecchi, G. A.

2012-01-01

The cultural evolution of introspective thought has been recognized to undergo a drastic change during the middle of the first millennium BC. This period, known as the “Axial Age,” saw the birth of religions and philosophies still alive in modern culture, as well as the transition from orality to literacy—which led to the hypothesis of a link between introspection and literacy. Here we set out to examine the evolution of introspection in the Axial Age, studying the cultural record of the Greco-Roman and Judeo-Christian literary traditions. Using a statistical measure of semantic similarity, we identify a single “arrow of time” in the Old and New Testaments of the Bible, and a more complex non-monotonic dynamics in the Greco-Roman tradition reflecting the rise and fall of the respective societies. A comparable analysis of the twentieth century cultural record shows a steady increase in the incidence of introspective topics, punctuated by abrupt declines during and preceding the First and Second World Wars. Our results show that (a) it is possible to devise a consistent metric to quantify the history of a high-level concept such as introspection, cementing the path for a new quantitative philology and (b) to the extent that it is captured in the cultural record, the increased ability of human thought for self-reflection that the Axial Age brought about is still heavily determined by societal contingencies beyond the orality-literacy nexus. PMID:23015783

Recent Evolution of the Mont Saint-Michel Bay as seen by ALOS AVNIR-2 Data (ADEN AO 3643)

NASA Astrophysics Data System (ADS)

Deroin, Jean-Paul; Bilaudeau, Clelia; Deffontaines, Benoit

2008-11-01

The ALOS AVNIR-2 scene acquired on October 24, 2007 has been used for drawing a new map of the Mont Saint-Michel Bay. This area is characterised by a large dry-fallen tidal flat, one of the largest in the world. The tidal records indicate that the ALOS datatake was acquired in favorable conditions, the elevation of the sea at 2.56 m being very close to the theoretical minimum value (about 2.30 m). In these conditions, the largest tidal flat observed by a sun-synchronous satellite on the Mont Saint-Michel Bay is exposed.

Astrobiology Extends Biology into Deep Time and Space

NASA Technical Reports Server (NTRS)

Desmarais, David

2003-01-01

To understand our own origins and to search for biospheres beyond Earth, we need a more robust concept of life itself. We must learn how to discriminate between attributes that are fundamental to all living systems versus those that represent principally local outcomes of long-term survival on Earth. We should identify the most basic environmental needs of life, chart the distribution of other habitable worlds, and understand the factors that created their distribution. Studies of microbial communities and the geologic record will be summarized that offer clues about the early evolution of our own biosphere as well as the signatures of life that we might find in the heavens.

SWS2 visual pigment evolution as a test of historically contingent patterns of plumage color evolution in Warblers

PubMed Central

Bloch, Natasha I.; Morrow, James M.; Chang, Belinda S.W.; Price, Trevor D.

2014-01-01

Distantly related clades that occupy similar environments may differ due to the lasting imprint of their ancestors – historical contingency. The New World warblers (Parulidae) and Old World warblers (Phylloscopidae) are ecologically similar clades that differ strikingly in plumage coloration. We studied genetic and functional evolution of the short-wavelength sensitive visual pigments (SWS2 and SWS1) to ask if altered color perception could contribute to the plumage color differences between clades. We show SWS2 is short-wavelength shifted in birds that occupy open environments, such as finches, compared to those in closed environments, including warblers. Phylogenetic reconstructions indicate New World warblers were derived from a finch-like form that colonized from the Old World 15-20Ma. During this process the SWS2 gene accumulated 6 substitutions in branches leading to New World warblers, inviting the hypothesis that passage through a finch-like ancestor resulted in SWS2 evolution. In fact, we show spectral tuning remained similar across warblers as well as the finch ancestor. Results reject the hypothesis of historical contingency based on opsin spectral tuning, but point to evolution of other aspects of visual pigment function. Using the approach outlined here, historical contingency becomes a generally testable theory in systems where genotype and phenotype can be connected. PMID:25496318

Alternative Fuels Data Center: Silicon Valley-based Electric Vehicle Parade

Science.gov Websites

Breaks Guinness World Record Silicon Valley-based Electric Vehicle Parade Breaks Guinness World Parade Breaks Guinness World Record on Facebook Tweet about Alternative Fuels Data Center: Silicon Valley -based Electric Vehicle Parade Breaks Guinness World Record on Twitter Bookmark Alternative Fuels Data

Carbonaceous Chondrite Meteorites: the Chronicle of a Potential Evolutionary Path between Stars and Life

NASA Astrophysics Data System (ADS)

Pizzarello, Sandra; Shock, Everett

2017-09-01

The biogenic elements, H, C, N, O, P and S, have a long cosmic history, whose evolution can still be observed in diverse locales of the known universe, from interstellar clouds of gas and dust, to pre-stellar cores, nebulas, protoplanetary discs, planets and planetesimals. The best analytical window into this cosmochemical evolution as it neared Earth has been provided so far by the small bodies of the Solar System, some of which were not significantly altered by the high gravitational pressures and temperatures that accompanied the formation of larger planets and may carry a pristine record of early nebular chemistry. Asteroids have delivered such records, as their fragments reach the Earth frequently and become available for laboratory analyses. The Carbonaceous Chondrite meteorites (CC) are a group of such fragments with the further distinction of containing abundant organic materials with structures as diverse as kerogen-like macromolecules and simpler compounds with identical counterparts in Earth's biosphere. All have revealed a lineage to cosmochemical synthetic regimes. Several CC show that asteroids underwent aqueous alteration of their minerals or rock metamorphism but may yet yield clues to the reactivity of organic compounds during parent-body processes, on asteroids as well as larger ocean worlds and planets. Whether the exogenous delivery by meteorites held an advantage in Earth's molecular evolution remains an open question as many others regarding the origins of life are. Nonetheless, the natural samples of meteorites allow exploring the physical and chemical processes that might have led to a selected chemical pool amenable to the onset of life. [Figure not available: see fulltext.

Carbonaceous Chondrite Meteorites: the Chronicle of a Potential Evolutionary Path between Stars and Life.

PubMed

Pizzarello, Sandra; Shock, Everett

2017-09-01

The biogenic elements, H, C, N, O, P and S, have a long cosmic history, whose evolution can still be observed in diverse locales of the known universe, from interstellar clouds of gas and dust, to pre-stellar cores, nebulas, protoplanetary discs, planets and planetesimals. The best analytical window into this cosmochemical evolution as it neared Earth has been provided so far by the small bodies of the Solar System, some of which were not significantly altered by the high gravitational pressures and temperatures that accompanied the formation of larger planets and may carry a pristine record of early nebular chemistry. Asteroids have delivered such records, as their fragments reach the Earth frequently and become available for laboratory analyses. The Carbonaceous Chondrite meteorites (CC) are a group of such fragments with the further distinction of containing abundant organic materials with structures as diverse as kerogen-like macromolecules and simpler compounds with identical counterparts in Earth's biosphere. All have revealed a lineage to cosmochemical synthetic regimes. Several CC show that asteroids underwent aqueous alteration of their minerals or rock metamorphism but may yet yield clues to the reactivity of organic compounds during parent-body processes, on asteroids as well as larger ocean worlds and planets. Whether the exogenous delivery by meteorites held an advantage in Earth's molecular evolution remains an open question as many others regarding the origins of life are. Nonetheless, the natural samples of meteorites allow exploring the physical and chemical processes that might have led to a selected chemical pool amenable to the onset of life. Graphical Abstract ᅟ.

Refractory Sampling Links Efficiency and Costs of Sensory Encoding to Stimulus Statistics

PubMed Central

Song, Zhuoyi

2014-01-01

Sensory neurons integrate information about the world, adapting their sampling to its changes. However, little is understood mechanistically how this primary encoding process, which ultimately limits perception, depends upon stimulus statistics. Here, we analyze this open question systematically by using intracellular recordings from fly (Drosophila melanogaster and Coenosia attenuata) photoreceptors and corresponding stochastic simulations from biophysically realistic photoreceptor models. Recordings show that photoreceptors can sample more information from naturalistic light intensity time series (NS) than from Gaussian white-noise (GWN), shuffled-NS or Gaussian-1/f stimuli; integrating larger responses with higher signal-to-noise ratio and encoding efficiency to large bursty contrast changes. Simulations reveal how a photoreceptor's information capture depends critically upon the stochastic refractoriness of its 30,000 sampling units (microvilli). In daylight, refractoriness sacrifices sensitivity to enhance intensity changes in neural image representations, with more and faster microvilli improving encoding. But for GWN and other stimuli, which lack longer dark contrasts of real-world intensity changes that reduce microvilli refractoriness, these performance gains are submaximal and energetically costly. These results provide mechanistic reasons why information sampling is more efficient for natural/naturalistic stimulation and novel insight into the operation, design, and evolution of signaling and code in sensory neurons. PMID:24849356

Online evolution reconstruction from a single measurement record with random time intervals for quantum communication

NASA Astrophysics Data System (ADS)

Zhou, Hua; Su, Yang; Wang, Rong; Zhu, Yong; Shen, Huiping; Pu, Tao; Wu, Chuanxin; Zhao, Jiyong; Zhang, Baofu; Xu, Zhiyong

2017-10-01

Online reconstruction of a time-variant quantum state from the encoding/decoding results of quantum communication is addressed by developing a method of evolution reconstruction from a single measurement record with random time intervals. A time-variant two-dimensional state is reconstructed on the basis of recovering its expectation value functions of three nonorthogonal projectors from a random single measurement record, which is composed from the discarded qubits of the six-state protocol. The simulated results prove that our method is robust to typical metro quantum channels. Our work extends the Fourier-based method of evolution reconstruction from the version for a regular single measurement record with equal time intervals to a unified one, which can be applied to arbitrary single measurement records. The proposed protocol of evolution reconstruction runs concurrently with the one of quantum communication, which can facilitate the online quantum tomography.

Predicting the evolution of complex networks via similarity dynamics

NASA Astrophysics Data System (ADS)

Wu, Tao; Chen, Leiting; Zhong, Linfeng; Xian, Xingping

2017-01-01

Almost all real-world networks are subject to constant evolution, and plenty of them have been investigated empirically to uncover the underlying evolution mechanism. However, the evolution prediction of dynamic networks still remains a challenging problem. The crux of this matter is to estimate the future network links of dynamic networks. This paper studies the evolution prediction of dynamic networks with link prediction paradigm. To estimate the likelihood of the existence of links more accurate, an effective and robust similarity index is presented by exploiting network structure adaptively. Moreover, most of the existing link prediction methods do not make a clear distinction between future links and missing links. In order to predict the future links, the networks are regarded as dynamic systems in this paper, and a similarity updating method, spatial-temporal position drift model, is developed to simulate the evolutionary dynamics of node similarity. Then the updated similarities are used as input information for the future links' likelihood estimation. Extensive experiments on real-world networks suggest that the proposed similarity index performs better than baseline methods and the position drift model performs well for evolution prediction in real-world evolving networks.

The first whole genome and transcriptome of the cinereous vulture reveals adaptation in the gastric and immune defense systems and possible convergent evolution between the Old and New World vultures.

PubMed

Chung, Oksung; Jin, Seondeok; Cho, Yun Sung; Lim, Jeongheui; Kim, Hyunho; Jho, Sungwoong; Kim, Hak-Min; Jun, JeHoon; Lee, HyeJin; Chon, Alvin; Ko, Junsu; Edwards, Jeremy; Weber, Jessica A; Han, Kyudong; O'Brien, Stephen J; Manica, Andrea; Bhak, Jong; Paek, Woon Kee

2015-10-21

The cinereous vulture, Aegypius monachus, is the largest bird of prey and plays a key role in the ecosystem by removing carcasses, thus preventing the spread of diseases. Its feeding habits force it to cope with constant exposure to pathogens, making this species an interesting target for discovering functionally selected genetic variants. Furthermore, the presence of two independently evolved vulture groups, Old World and New World vultures, provides a natural experiment in which to investigate convergent evolution due to obligate scavenging. We sequenced the genome of a cinereous vulture, and mapped it to the bald eagle reference genome, a close relative with a divergence time of 18 million years. By comparing the cinereous vulture to other avian genomes, we find positively selected genetic variations in this species associated with respiration, likely linked to their ability of immune defense responses and gastric acid secretion, consistent with their ability to digest carcasses. Comparisons between the Old World and New World vulture groups suggest convergent gene evolution. We assemble the cinereous vulture blood transcriptome from a second individual, and annotate genes. Finally, we infer the demographic history of the cinereous vulture which shows marked fluctuations in effective population size during the late Pleistocene. We present the first genome and transcriptome analyses of the cinereous vulture compared to other avian genomes and transcriptomes, revealing genetic signatures of dietary and environmental adaptations accompanied by possible convergent evolution between the Old World and New World vultures.

Continuous 1.3-million-year record of East African hydroclimate, and implications for patterns of evolution and biodiversity

NASA Astrophysics Data System (ADS)

Lyons, Robert P.; Scholz, Christopher A.; Cohen, Andrew S.; King, John W.; Brown, Erik T.; Ivory, Sarah J.; Johnson, Thomas C.; Deino, Alan L.; Reinthal, Peter N.; McGlue, Michael M.; Blome, Margaret W.

2015-12-01

The transport of moisture in the tropics is a critical process for the global energy budget and on geologic timescales, has markedly influenced continental landscapes, migratory pathways, and biological evolution. Here we present a continuous, first-of-its-kind 1.3-My record of continental hydroclimate and lake-level variability derived from drill core data from Lake Malawi, East Africa (9-15° S). Over the Quaternary, we observe dramatic shifts in effective moisture, resulting in large-scale changes in one of the world's largest lakes and most diverse freshwater ecosystems. Results show evidence for 24 lake level drops of more than 200 m during the Late Quaternary, including 15 lowstands when water levels were more than 400 m lower than modern. A dramatic shift is observed at the Mid-Pleistocene Transition (MPT), consistent with far-field climate forcing, which separates vastly different hydroclimate regimes before and after ∼800,000 years ago. Before 800 ka, lake levels were lower, indicating a climate drier than today, and water levels changed frequently. Following the MPT high-amplitude lake level variations dominate the record. From 800 to 100 ka, a deep, often overfilled lake occupied the basin, indicating a wetter climate, but these highstands were interrupted by prolonged intervals of extreme drought. Periods of high lake level are observed during times of high eccentricity. The extreme hydroclimate variability exerted a profound influence on the Lake Malawi endemic cichlid fish species flock; the geographically extensive habitat reconfiguration provided novel ecological opportunities, enabling new populations to differentiate rapidly to distinct species.

Continuous 1.3-million-year record of East African hydroclimate, and implications for patterns of evolution and biodiversity.

PubMed

Lyons, Robert P; Scholz, Christopher A; Cohen, Andrew S; King, John W; Brown, Erik T; Ivory, Sarah J; Johnson, Thomas C; Deino, Alan L; Reinthal, Peter N; McGlue, Michael M; Blome, Margaret W

2015-12-22

The transport of moisture in the tropics is a critical process for the global energy budget and on geologic timescales, has markedly influenced continental landscapes, migratory pathways, and biological evolution. Here we present a continuous, first-of-its-kind 1.3-My record of continental hydroclimate and lake-level variability derived from drill core data from Lake Malawi, East Africa (9-15° S). Over the Quaternary, we observe dramatic shifts in effective moisture, resulting in large-scale changes in one of the world's largest lakes and most diverse freshwater ecosystems. Results show evidence for 24 lake level drops of more than 200 m during the Late Quaternary, including 15 lowstands when water levels were more than 400 m lower than modern. A dramatic shift is observed at the Mid-Pleistocene Transition (MPT), consistent with far-field climate forcing, which separates vastly different hydroclimate regimes before and after ∼800,000 years ago. Before 800 ka, lake levels were lower, indicating a climate drier than today, and water levels changed frequently. Following the MPT high-amplitude lake level variations dominate the record. From 800 to 100 ka, a deep, often overfilled lake occupied the basin, indicating a wetter climate, but these highstands were interrupted by prolonged intervals of extreme drought. Periods of high lake level are observed during times of high eccentricity. The extreme hydroclimate variability exerted a profound influence on the Lake Malawi endemic cichlid fish species flock; the geographically extensive habitat reconfiguration provided novel ecological opportunities, enabling new populations to differentiate rapidly to distinct species.

Food and nutrition labelling in Thailand: a long march from subsistence producers to international traders

PubMed Central

Rimpeekool, Wimalin; Seubsman, Sam-ang; Banwell, Cathy; Kirk, Martyn; Yiengprugsawan, Vasoontara; Sleigh, Adrian

2015-01-01

This paper reviews the evolution of Thai food and nutrition label policies and Thailand’s international role relating to food product safety and standards. The historical record has been interpreted to identify future trends and challenges related to food labelling. These challenges are arising in Thailand and many similar emerging economies. Thailand has a good reputation in world food markets and is now becoming a global leader in food production and export. It has become deeply involved with regulations and standards applied by World Trade Organization and Codex Alimentarius while serving its own population with a safe and secure food supply. For consumers considering Thai food products, food labels can provide useful nutrition information and help build trust. Thais began a century ago with policies and laws to enhance food safety and to protect Thai consumers. During the lengthy journey from national to global standards Thai food labels have evolved and now contribute to international food labelling policies. This contribution comes from the perspective of a leading middle income south-east Asian food producer now trading with high income countries around the world. The story of that journey – a case study for many other countries in a similar situation – has not previously been told. This article provides information for policy makers dealing with food labelling, embedding trends and tensions for one middle income food exporter in a long history. Information captured here should be helpful for other middle income countries, especially those with limited records. This strategic knowledge will enable better decisions for future policies. PMID:26538793

Multilocus phylogeny and phylogenomics of Eriochrysis P. Beauv. (Poaceae-Andropogoneae): Taxonomic implications and evidence of interspecific hybridization.

PubMed

Welker, Cassiano A D; Souza-Chies, Tatiana T; Longhi-Wagner, Hilda M; Peichoto, Myriam Carolina; McKain, Michael R; Kellogg, Elizabeth A

2016-06-01

Species delimitation is a vital issue concerning evolutionary biology and conservation of biodiversity. However, it is a challenging task for several reasons, including the low interspecies variability of markers currently used in phylogenetic reconstructions and the occurrence of reticulate evolution and polyploidy in many lineages of flowering plants. The first phylogeny of the grass genus Eriochrysis is presented here, focusing on the New World species, in order to examine its relationships to other genera of the subtribe Saccharinae/tribe Andropogoneae and to define the circumscriptions of its taxonomically complicated species. Molecular cloning and sequencing of five regions of four low-copy nuclear genes (apo1, d8, ep2-ex7 and ep2-ex8, kn1) were performed, as well as complete plastome sequencing. Trees were reconstructed using maximum parsimony, maximum likelihood, and Bayesian inference analyses. The present phylogenetic analyses indicate that Eriochrysis is monophyletic and the Old World E. pallida is sister to the New World species. Subtribe Saccharinae is polyphyletic, as is the genus Eulalia. Based on nuclear and plastome sequences plus morphology, we define the circumscriptions of the New World species of Eriochrysis: E. laxa is distinct from E. warmingiana, and E. villosa is distinct from E. cayennensis. Natural hybrids occur between E. laxa and E. villosa. The hybrids are probably tetraploids, based on the number of paralogues in the nuclear gene trees. This is the first record of a polyploid taxon in the genus Eriochrysis. Some incongruities between nuclear genes and plastome analyses were detected and are potentially caused by incomplete lineage sorting and/or ancient hybridization. The set of low-copy nuclear genes used in this study seems to be sufficient to resolve phylogenetic relationships and define the circumscriptions of other species complexes in the grass family and relatives, even in the presence of polyploidy and reticulate evolution. Complete plastome sequencing is also a promising tool for phylogenetic inference. Copyright © 2016 Elsevier Inc. All rights reserved.

In Galápagos … and Uncomfortable with Evolution

ERIC Educational Resources Information Center

Cotner, Sehoya; Graczyk, Hannah; Rodríguez Garcia, José Luis; Moore, Randy

2016-01-01

In June 2013, the third World Evolution Summit convened on San Cristóbal, hosting scientists from around the world (Paz-y-Miño-C and Espinosa 2013)--neither the first nor likely the last gathering of biologists on these remote islands. Clearly, both locals and an international audience perceive Galápagos as figuring prominently in discourse about…

Science, religion, and society: the problem of evolution in America.

PubMed

Coyne, Jerry A

2012-08-01

American resistance to accepting evolution is uniquely high among First World countries. This is due largely to the extreme religiosity of the United States, which is much higher than that of comparably advanced nations, and to the resistance of many religious people to the facts and supposed implications of evolution. The prevalence of religious belief in the United States suggests that outreach by scientists alone will not have a huge effect in increasing the acceptance of evolution, nor will the strategy of trying to convince the faithful that evolution is compatible with their religion. Because creationism is a symptom of religion, another strategy to promote evolution involves loosening the grip of faith on America. This is easier said than done, for recent sociological surveys show that religion is highly correlated with the dysfunctionality of a society, and various measures of societal health show that the United States is one of the most socially dysfunctional First World countries. Widespread acceptance of evolution in America, then, may have to await profound social change. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

12 CFR 309.4 - Publicly available records.

Code of Federal Regulations, 2010 CFR

2010-01-01

... INFORMATION § 309.4 Publicly available records. (a) Records available on the FDIC's World Wide Web page—(1... on the FDIC's World Wide Web page, located at: http://www.fdic.gov. The FDIC has elected to publish a broad range of materials on its World Wide Web page, including consumer guides; financial and...

Introducing Evolution to Non-Biology Majors via the Fossil Record: A Case Study from the Israeli High School System.

ERIC Educational Resources Information Center

Dodick, Jeff; Orion, Nir

2003-01-01

Discusses challenges faced in the teaching and learning of evolution. Presents a curricular program and a case study on evolutionary biology. Investigates students' conceptual knowledge after exposure to the program "From Dinosaurs to Darwin," which focuses on fossil records as evidence of evolution. (Contains 32 references.) (YDS)

Remote Sensing and Holocene Vegetation: History of Global Change

NASA Technical Reports Server (NTRS)

DAntoni, Hector; Schaebitz, Frank

1995-01-01

Predictions of the future evolution of the earth's atmospheric chemistry and its impact on global circulation patterns are based on Global Climate Models (GCM's) that integrate the complex interactions of the biosphere, atmosphere and the oceans. Most of the available records of climate and environment are shortterm records (from decades to a few hundred years) with convolved information of real trends and short-term fluctuations. GCM's must be tested beyond the short-term record of climate and environment to insure that predictions are based on trends and therefore are appropriate to support long term policy making. An appropriate timeframe should extend over the Holocene period (the last 10,000 years) when most contemporary climate and environmental processes began. Since its inception in 1916, pollen analysis has successfully reconstructed the paleoecology of the last 10,000 years for many sites around the world, thus providing a powerful time-link between short- and long-term processes in the biosphere. However, pollen analytic results cannot be used in physiological models driven by remotely sensed data. Further, modern ecology and climate data are necessary to calibrate pollen analytical models. These are available for extensive regions in the northern hemisphere, particularly for eastern United States and Canada, and western Europe. In other parts of the world, weather stations are scattered, records extend over a period of only few years, and there are no systematic climate records for large portions of the globe. This is the case of Patagonia in Argentina where a few weather stations are located close to the Atlantic seaports, fewer stations are in towns located near the eastern Andean foothill, and fewer still are scattered on the extensive Patagonian plateau. This problem became evident after completion of the Argentine-German Program of Palynology (PROPAL), a cooperative effort of National University of Mar del Plata (Argentina) and University Bamberg (Germany) to produce a modern pollen database for the Pampa and Patagonia regions.

NREL, University of Washington Scientists Elevate Quantum Dot Solar Cell

Science.gov Websites

World Record to 13.4 Percent | NREL | News | NREL NREL, University of Washington Scientists Elevate Quantum Dot Solar Cell World Record to 13.4 Percent News Release: NREL, University of Washington Scientists Elevate Quantum Dot Solar Cell World Record to 13.4 Percent October 27, 2017 Researchers at the

Holocene moisture variations over the arid central Asia revealed by a comprehensive sand-dune record from the central Tian Shan, NW China

NASA Astrophysics Data System (ADS)

Long, Hao; Shen, Ji; Chen, Jianhui; Tsukamoto, Sumiko; Yang, Linhai; Cheng, Hongyi; Frechen, Manfred

2017-10-01

Arid central Asia (ACA) is one of the largest arid (desert) areas in the world, and its climate is dominated by the westerlies. In this study, we examined sand dune evolution from the Bayanbulak Basin in the Tian Shan (Xinjiang, NW China), aiming to infer the Holocene moisture history of the ACA. Combined with stratigraphic observation and environmental proxies analysis (grain size, magnetic susceptibility and total organic content), large numbers of luminescence ages from multiple sites (eight sections, 79 samples) were applied to reconstruct the evolution of the sand dune accumulation in the study basin. The overall results imply very dry conditions characterized by sand dune accumulation at ∼12-6.5 ka, a wet interval between ∼6.5 and 0.8 ka when soil formation occurred, and decreased moisture during the last 0.8 ka. This moisture variation pattern is generally consistent with that inferred from many lacustrine records in the core zone of ACA, suggesting a widespread dry period in the early-to-middle Holocene and relatively wet middle-to-late Holocene. Thus, the moisture history derived from the current sand dune system contrasts with that in Asian monsoon areas, which are characterized by a strong monsoon (high precipitation) in the early and mid-Holocene and a weak monsoon (low precipitation and dry climate) during the late Holocene. Our results strongly suggest that the winter solar insolation and the external boundary conditions such as atmospheric CO2 concentration, ice sheets, and meltwater fluxes, have been major influential factors triggering the Holocene moisture evolution in the core zone of ACA.

Precipitation Records-HDSC/OWP

Science.gov Websites

resources and services. Greatest observed point precipitation values for the world and the USA US Comparison of the greatest point precipitation values for the world and the USA. World records (map, table) USA

Gaps in the Rock and Fossil Records and Implications for the Rate and Mode of Evolution.

ERIC Educational Resources Information Center

Smith, Grant Sackett

1988-01-01

Examines three types of gaps in the fossil record: real gaps, imaginary gaps, and temporary gaps. Reviews some recent evidence concerning evolution from the paleontological record of microfossils, invertebrates, and vertebrates in order to make some general conclusions regarding the manner in which life evolved on earth. (CW)

Getting the measure of extinction.

PubMed

Mace, G

1998-01-01

Like all species, plants, mammals, and birds have been subject to extinction as a fundamental part of evolution. Indeed, only about 2-4% of all the species that have ever lived during the 600 million years of the fossil record still survive today. Looking at the fossil record, it can be said that invertebrate species and mammals have had an average life span of 5-10 and 1-2 million years, respectively. More recent extinction records for birds and mammals lost over the last half of the century indicate that 1 out of 14,000 species becomes extinct each year, giving each species an average life span of 10,000 years--100 to 1000 times shorter than the lifetime of species in the fossil record. Drawing on the World's Conservation Union Red List of threatened animals (1996), species lifetimes of birds, mammals and reptiles are estimated at 300-500 years and 100-1000 years across broader groups. In general, these estimates show that extinction rates today are 1000 to 10,000 times higher than in the past, making current rates of species loss at least equivalent to the mass extinctions in the past. A major difference, however, is the fact that almost all extinctions that have transpired today are due to the impact of human activities.

Using modeling to understand how athletes in different disciplines solve the same problem: swimming versus running versus speed skating.

PubMed

de Koning, Jos J; Foster, Carl; Lucia, Alejandro; Bobbert, Maarten F; Hettinga, Florentina J; Porcari, John P

2011-06-01

Every new competitive season offers excellent examples of human locomotor abilities, regardless of the sport. As a natural consequence of competitions, world records are broken every now and then. World record races not only offer spectators the pleasure of watching very talented and highly trained athletes performing muscular tasks with remarkable skill, but also represent natural models of the ultimate expression of human integrated muscle biology, through strength, speed, or endurance performances. Given that humans may be approaching our species limit for muscular power output, interest in how athletes improve on world records has led to interest in the strategy of how limited energetic resources are best expended over a race. World record performances may also shed light on how athletes in different events solve exactly the same problem-minimizing the time required to reach the finish line. We have previously applied mathematical modeling to the understanding of world record performances in terms of improvements in facilities/equipment and improvements in the athletes' physical capacities. In this commentary, we attempt to demonstrate that differences in world record performances in various sports can be explained using a very simple modeling process.

Significance of the evolutionary α1,3-galactosyltransferase (GGTA1) gene inactivation in preventing extinction of apes and old world monkeys.

PubMed

Galili, Uri

2015-01-01

The α1,3-galactosyltransferase (α1,3GT or GGTA1) gene displays unique evolutionary characteristics. This gene appeared early in mammalian evolution and is absent in other vertebrates. The α1,3GT gene is active in marsupials, nonprimate placental mammals, lemurs (prosimians) and New World monkeys, encoding the α1,3GT enzyme that synthesizes a carbohydrate antigen called "α-gal epitope." The α-gal epitope is present in large numbers on cell membrane glycolipids and glycoproteins. The α1,3GT gene was inactivated in ancestral Old World monkeys and apes by frameshift single-base deletions forming premature stop codons. Because of this gene inactivation, humans, apes, and Old World monkeys lack α-gal epitopes and naturally produce an antibody called the "anti-Gal antibody" which binds specifically to α-gal epitopes and which is the most abundant antibody in humans. The evolutionary event that resulted in the inactivation of the α1,3GT gene in ancestral Old World primates could have been mediated by a pathogen endemic to Eurasia-Africa landmass that exerted pressure for selection of primate populations lacking the α-gal epitope. Once the α-gal epitope was eliminated, primates could produce the anti-Gal antibody, possibly as means of defense against pathogens expressing this epitope. This assumption is supported by the fossil record demonstrating an almost complete extinction of apes in the late Miocene and failure of Old World monkeys to radiate into multiple species before that period. A present outcome of this evolutionary event is the anti-Gal-mediated rejection of mammalian xenografts expressing α-gal epitopes in humans, apes, and Old World monkeys.

World Literature in the Age of Globalization: Reflections on an Anthology.

ERIC Educational Resources Information Center

Hassan, Wail S.

2000-01-01

Addresses the evolution of the most authoritative and widely used textbook in world literature courses in the United States, "The Norton Anthology of World Masterpieces." Questions if the "Norton Anthology" has provided educators who are committed to the teaching of world literature from non-Eurocentric perspectives with a…

Where Did We Come From?: A Communication Analysis of the Creation-Evolution Controversy as Depicted in "Time,""Newsweek," and "U.S. News and World Report."

ERIC Educational Resources Information Center

Pullum, Stephen J.

Noting the potential effect of print media on society, a study addressed the question of how "Time,""Newsweek," and "U.S. News and World Report" (USNWR) have presented the creation-evolution issue (particularly as taught in public schools) to its readers. Thirty-nine articles published form 1980 to 1992 were analyzed:…

Adaptation, plant evolution, and the fossil record

NASA Technical Reports Server (NTRS)

Knoll, A. H.; Niklas, K. J.

1987-01-01

The importance of adaptation in determining patterns of evolution has become an important focus of debate in evolutionary biology. As it pertains to paleobotany, the issue is whether or not adaptive evolution mediated by natural selection is sufficient to explain the stratigraphic distributions of taxa and character states observed in the plant fossil record. One means of addressing this question is the functional evaluation of stratigraphic series of plant organs set in the context of paleoenvironmental change and temporal patterns of floral composition within environments. For certain organ systems, quantitative estimates of biophysical performance can be made on the basis of structures preserved in the fossil record. Performance estimates for plants separated in time or space can be compared directly. Implicit in different hypotheses of the forces that shape the evolutionary record (e.g. adaptation, mass extinction, rapid environmental change, chance) are predictions about stratigraphic and paleoenvironmental trends in the efficacy of functional performance. Existing data suggest that following the evolution of a significant structural innovation, adaptation for improved functional performance can be a major determinant of evolutionary changes in plants; however, there are structural and development limits to functional improvement, and once these are reached, the structure in question may no longer figure strongly in selection until and unless a new innovation evolves. The Silurian-Devonian paleobotanical record is consistent with the hypothesis that the succession of lowland floodplain dominants preserved in the fossil record of this interval was determined principally by the repeated evolution of new taxa that rose to ecological importance because of competitive advantages conferred by improved biophysical performance. This does not seem to be equally true for Carboniferous-Jurassic dominants of swamp and lowland floodplain environments. In these cases, environmental disruption appears to have been a major factor in shaping the fossil record. This does not mean that continuing adaptation was not important during this interval, but it may indicate that adaptive evolution was strongest in environments other than those best represented in the paleobotanical record.

Adaptation, plant evolution, and the fossil record.

PubMed

Knoll, A H; Niklas, K J

1987-01-01

The importance of adaptation in determining patterns of evolution has become an important focus of debate in evolutionary biology. As it pertains to paleobotany, the issue is whether or not adaptive evolution mediated by natural selection is sufficient to explain the stratigraphic distributions of taxa and character states observed in the plant fossil record. One means of addressing this question is the functional evaluation of stratigraphic series of plant organs set in the context of paleoenvironmental change and temporal patterns of floral composition within environments. For certain organ systems, quantitative estimates of biophysical performance can be made on the basis of structures preserved in the fossil record. Performance estimates for plants separated in time or space can be compared directly. Implicit in different hypotheses of the forces that shape the evolutionary record (e.g. adaptation, mass extinction, rapid environmental change, chance) are predictions about stratigraphic and paleoenvironmental trends in the efficacy of functional performance. Existing data suggest that following the evolution of a significant structural innovation, adaptation for improved functional performance can be a major determinant of evolutionary changes in plants; however, there are structural and development limits to functional improvement, and once these are reached, the structure in question may no longer figure strongly in selection until and unless a new innovation evolves. The Silurian-Devonian paleobotanical record is consistent with the hypothesis that the succession of lowland floodplain dominants preserved in the fossil record of this interval was determined principally by the repeated evolution of new taxa that rose to ecological importance because of competitive advantages conferred by improved biophysical performance. This does not seem to be equally true for Carboniferous-Jurassic dominants of swamp and lowland floodplain environments. In these cases, environmental disruption appears to have been a major factor in shaping the fossil record. This does not mean that continuing adaptation was not important during this interval, but it may indicate that adaptive evolution was strongest in environments other than those best represented in the paleobotanical record.

Foundations of teamwork and collaboration.

PubMed

Driskell, James E; Salas, Eduardo; Driskell, Tripp

2018-01-01

The term teamwork has graced countless motivational posters and office walls. However, although teamwork is often easy to observe, it is somewhat more difficult to describe and yet more difficult to produce. At a broad level, teamwork is the process through which team members collaborate to achieve task goals. Teamwork refers to the activities through which team inputs translate into team outputs such as team effectiveness and satisfaction. In this article, we describe foundational research underlying current research on teamwork. We examine the evolution of team process models and outline primary teamwork dimensions. We discuss selection, training, and design approaches to enhancing teamwork, and note current applications of teamwork research in real-world settings. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

'Big Data' Collaboration: Exploring, Recording and Sharing Enterprise Knowledge

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

Sukumar, Sreenivas R; Ferrell, Regina Kay

2013-01-01

As data sources and data size proliferate, knowledge discovery from "Big Data" is starting to pose several challenges. In this paper, we address a specific challenge in the practice of enterprise knowledge management while extracting actionable nuggets from diverse data sources of seemingly-related information. In particular, we address the challenge of archiving knowledge gained through collaboration, dissemination and visualization as part of the data analysis, inference and decision-making lifecycle. We motivate the implementation of an enterprise data-discovery and knowledge recorder tool, called SEEKER based on real world case-study. We demonstrate SEEKER capturing schema and data-element relationships, tracking the data elementsmore » of value based on the queries and the analytical artifacts that are being created by analysts as they use the data. We show how the tool serves as digital record of institutional domain knowledge and a documentation for the evolution of data elements, queries and schemas over time. As a knowledge management service, a tool like SEEKER saves enterprise resources and time by avoiding analytic silos, expediting the process of multi-source data integration and intelligently documenting discoveries from fellow analysts.« less

Descent with modification and the archaeological record

PubMed Central

Shennan, Stephen

2011-01-01

Recent years have seen major advances in our understanding of the way in which cultural transmission takes place and the factors that affect it. The theoretical foundations of those advances have been built by postulating the existence of a variety of different processes and deriving their consequences mathematically or by simulation. The operation of these processes in the real world can be studied through experiment and naturalistic observation. In contrast, archaeologists have an ‘inverse problem’. For them the object of study is the residues of different behaviours represented by the archaeological record and the problem is to infer the microscale processes that produced them, a vital task for cultural evolution since this is the only direct record of past cultural patterns. The situation is analogous to that faced by population geneticists scanning large number of genes and looking for evidence of selection as opposed to drift, but more complicated for many reasons, not least the enormous variety of different forces that affect cultural transmission. This paper reviews the progress that has been made in inferring processes from patterns and the role of demography in those processes, together with the problems that have arisen. PMID:21357229

The planetary biology of cytochrome P450 aromatases.

PubMed

Gaucher, Eric A; Graddy, Logan G; Li, Tang; Simmen, Rosalia C M; Simmen, Frank A; Schreiber, David R; Liberles, David A; Janis, Christine M; Benner, Steven A

2004-08-17

Joining a model for the molecular evolution of a protein family to the paleontological and geological records (geobiology), and then to the chemical structures of substrates, products, and protein folds, is emerging as a broad strategy for generating hypotheses concerning function in a post-genomic world. This strategy expands systems biology to a planetary context, necessary for a notion of fitness to underlie (as it must) any discussion of function within a biomolecular system. Here, we report an example of such an expansion, where tools from planetary biology were used to analyze three genes from the pig Sus scrofa that encode cytochrome P450 aromatases-enzymes that convert androgens into estrogens. The evolutionary history of the vertebrate aromatase gene family was reconstructed. Transition redundant exchange silent substitution metrics were used to interpolate dates for the divergence of family members, the paleontological record was consulted to identify changes in physiology that correlated in time with the change in molecular behavior, and new aromatase sequences from peccary were obtained. Metrics that detect changing function in proteins were then applied, including KA/KS values and those that exploit structural biology. These identified specific amino acid replacements that were associated with changing substrate and product specificity during the time of presumed adaptive change. The combined analysis suggests that aromatase paralogs arose in pigs as a result of selection for Suoidea with larger litters than their ancestors, and permitted the Suoidea to survive the global climatic trauma that began in the Eocene. This combination of bioinformatics analysis, molecular evolution, paleontology, cladistics, global climatology, structural biology, and organic chemistry serves as a paradigm in planetary biology. As the geological, paleontological, and genomic records improve, this approach should become widely useful to make systems biology statements about high-level function for biomolecular systems.

The planetary biology of cytochrome P450 aromatases

PubMed Central

Gaucher, Eric A; Graddy, Logan G; Li, Tang; Simmen, Rosalia CM; Simmen, Frank A; Schreiber, David R; Liberles, David A; Janis, Christine M; Benner, Steven A

2004-01-01

Background Joining a model for the molecular evolution of a protein family to the paleontological and geological records (geobiology), and then to the chemical structures of substrates, products, and protein folds, is emerging as a broad strategy for generating hypotheses concerning function in a post-genomic world. This strategy expands systems biology to a planetary context, necessary for a notion of fitness to underlie (as it must) any discussion of function within a biomolecular system. Results Here, we report an example of such an expansion, where tools from planetary biology were used to analyze three genes from the pig Sus scrofa that encode cytochrome P450 aromatases–enzymes that convert androgens into estrogens. The evolutionary history of the vertebrate aromatase gene family was reconstructed. Transition redundant exchange silent substitution metrics were used to interpolate dates for the divergence of family members, the paleontological record was consulted to identify changes in physiology that correlated in time with the change in molecular behavior, and new aromatase sequences from peccary were obtained. Metrics that detect changing function in proteins were then applied, including KA/KS values and those that exploit structural biology. These identified specific amino acid replacements that were associated with changing substrate and product specificity during the time of presumed adaptive change. The combined analysis suggests that aromatase paralogs arose in pigs as a result of selection for Suoidea with larger litters than their ancestors, and permitted the Suoidea to survive the global climatic trauma that began in the Eocene. Conclusions This combination of bioinformatics analysis, molecular evolution, paleontology, cladistics, global climatology, structural biology, and organic chemistry serves as a paradigm in planetary biology. As the geological, paleontological, and genomic records improve, this approach should become widely useful to make systems biology statements about high-level function for biomolecular systems. PMID:15315709

"Evolution Canyon," a potential microscale monitor of global warming across life.

PubMed

Nevo, Eviatar

2012-02-21

Climatic change and stress is a major driving force of evolution. The effects of climate change on living organisms have been shown primarily on regional and global scales. Here I propose the "Evolution Canyon" (EC) microscale model as a potential life monitor of global warming in Israel and the rest of the world. The EC model reveals evolution in action at a microscale involving biodiversity divergence, adaptation, and incipient sympatric speciation across life from viruses and bacteria through fungi, plants, and animals. The EC consists of two abutting slopes separated, on average, by 200 m. The tropical, xeric, savannoid, "African" south-facing slope (AS = SFS) abuts the forested "European" north-facing slope (ES = NFS). The AS receives 200-800% higher solar radiation than the ES. The ES represents the south European forested maquis. The AS and ES exhibit drought and shade stress, respectively. Major adaptations on the AS are because of solar radiation, heat, and drought, whereas those on the ES relate to light stress and photosynthesis. Preliminary evidence suggests the extinction of some European species on the ES and AS. In Drosophila, a 10-fold higher migration was recorded in 2003 from the AS to ES. I advance some predictions that could be followed in diverse species in EC. The EC microclimatic model is optimal to track global warming at a microscale across life from viruses and bacteria to mammals in Israel, and in additional ECs across the planet.

“Evolution Canyon,” a potential microscale monitor of global warming across life

PubMed Central

Nevo, Eviatar

2012-01-01

Climatic change and stress is a major driving force of evolution. The effects of climate change on living organisms have been shown primarily on regional and global scales. Here I propose the “Evolution Canyon” (EC) microscale model as a potential life monitor of global warming in Israel and the rest of the world. The EC model reveals evolution in action at a microscale involving biodiversity divergence, adaptation, and incipient sympatric speciation across life from viruses and bacteria through fungi, plants, and animals. The EC consists of two abutting slopes separated, on average, by 200 m. The tropical, xeric, savannoid, “African” south-facing slope (AS = SFS) abuts the forested “European” north-facing slope (ES = NFS). The AS receives 200–800% higher solar radiation than the ES. The ES represents the south European forested maquis. The AS and ES exhibit drought and shade stress, respectively. Major adaptations on the AS are because of solar radiation, heat, and drought, whereas those on the ES relate to light stress and photosynthesis. Preliminary evidence suggests the extinction of some European species on the ES and AS. In Drosophila, a 10-fold higher migration was recorded in 2003 from the AS to ES. I advance some predictions that could be followed in diverse species in EC. The EC microclimatic model is optimal to track global warming at a microscale across life from viruses and bacteria to mammals in Israel, and in additional ECs across the planet. PMID:22308456

The role of play objects and object play in human cognitive evolution and innovation

PubMed Central

Johannsen, Niels N.; Högberg, Anders; Nowell, April; Lombard, Marlize

2018-01-01

Abstract In this contribution, we address a major puzzle in the evolution of human material culture: If maturing individuals just learn their parental generation's material culture, then what is the origin of key innovations as documented in the archeological record? We approach this question by coupling a life‐history model of the costs and benefits of experimentation with a niche‐construction perspective. Niche‐construction theory suggests that the behavior of organisms and their modification of the world around them have important evolutionary ramifications by altering developmental settings and selection pressures. Part of Homo sapiens' niche is the active provisioning of children with play objects — sometimes functional miniatures of adult tools — and the encouragement of object play, such as playful knapping with stones. Our model suggests that salient material culture innovation may occur or be primed in a late childhood or adolescence sweet spot when cognitive and physical abilities are sufficiently mature but before the full onset of the concerns and costs associated with reproduction. We evaluate the model against a series of archeological cases and make suggestions for future research. PMID:29446561

Cenozoic Icehouse Forcing Mechanisms on Coccolithophorid Evolution

NASA Astrophysics Data System (ADS)

Henderiks, J.

2007-12-01

An overall macroevolutionary size decrease in marine unicellular calcifying algae, the coccolithophores, is punctuated by distinct size responses that correlate to major climatic and paleoceanographic events during the Cenozoic. Notably, major size decreases in the ancestors of the modern blooming species Emiliania huxleyi and Gephyrocapsa oceanica are recorded at the Eocene-Oligocene transition (34 Ma) and in the late Miocene (9 Ma). Coccolithophorid cell size (as reconstructed from individual coccolith biometry) is likely influenced by a variety of passive and active evolutionary selection pressures, with specific factors, such as resource availability and climatic change, determining trends in specific intervals of time. This study presents biometric data of the Noelaerhabdacaea, Calcidiscaceae and Coccolithaceae families, which together represent the bulk of coccolith-carbonate buried in Cenozoic deep-sea sediments, from multiple Deep Sea Drilling Project and Ocean Drilling Project sites covering temperate to tropical regions in the Atlantic, Indian and Pacific oceans. Despite distinct regional ecologic responses at each site, striking correspondences within the global data set call for global forcing mechanisms on the size evolution and ecological success of coccolithophores in an 'icehouse' world.

Greenhouse to Icehouse Antarctic Paleoclimate and Ice History from George V Land and Adélie Land Shelf Sediments

NASA Astrophysics Data System (ADS)

Williams, T.; Escutia, C.; De Santis, L.; O'Brien, P.; Pekar, S. F.; Brinkhuis, H.; Domack, E. W.

2013-12-01

Along the George V and Adélie Land continental shelf of East Antarctica, shallowly-buried strata contain a record of Antarctica's climate and ice history from the lush forests of the Eocene greenhouse to the dynamic ice sheet margins of the Neogene. Short piston cores and dredges have recovered Early Cretaceous and Eocene organic-rich sediment at the seabed, and in 2010, IODP Expedition 318 recovered earliest Oligocene and early Pliocene subglacial and proglacial diamictites. However, challenging ice and drilling conditions from the JOIDES Resolution on the shelf resulted in poor core recovery and sites had to be abandoned before the stratigraphic targets could be reached. Therefore, in a new IODP drilling proposal submitted earlier this year, we propose to use the MeBo sea bed drill for improved core recovery and easier access to the shelf, and drill a stratigraphic transect of shallow (~80m) holes. To investigate the evolution of the Antarctic ice sheet in this sector, we target strata above and below regional erosional and downlap surfaces to date and characterize major episodes of ice sheet advance and retreat. These direct records of ice extent on the shelf can be set in the context of Southern Ocean records of temperature, ice-rafted debris (IRD) and latitudinal fluctuations of the opal belt, and hence we can relate ice sheet evolution to paleoclimate conditions. Targets include possible late Eocene precursor glaciations, the Eocene/Oligocene boundary erosion surface, Oligocene and Miocene ice extents, and ice margin fluctuations in the Pliocene. At the Cretaceous and Eocene proposed sites, marine and terrestrial temperature proxies and palynological records will provide information on high-latitude paleoenvironments and pole-equator temperature gradients. Here we present existing data from the area and the proposed new drill sites. The ice and climate history of the George V and Adélie Land margin can provide warm-world scenarios to help understand ice sheet instability in analogous future warm climates.

The World as Evolving Information

NASA Astrophysics Data System (ADS)

Gershenson, Carlos

This paper discusses the benefits of describing the world as information, especially in the study of the evolution of life and cognition. Traditional studies encounter problems because it is difficult to describe life and cognition in terms of matter and energy, since their laws are valid only at the physical scale. However, if matter and energy, as well as life and cognition, are described in terms of information, evolution can be described consistently as information becoming more complex.

Bruteau's philosophy of spiritual evolution and consciousness: foundation for a nursing cosmology.

PubMed

McCarthy, M Patrice

2011-01-01

The ontological foundation of the modern world view based on irreconcilable dichotomies has held hegemonic status since the dawn of the scientific revolution. The post-modern critique has exposed the inadequacies of the modern perspective and challenged the potential for any narrative to adequately ground a vision for the future. This paper proposes that the philosophy of Beatrice Bruteau can support a foundation for a visionary world view consistent with nursing's respect for human dignity and societal health. The author discusses the key concepts of Bruteau's perspective on societal evolution based on an integrated study of science, mathematics, religion, and philosophy. This perspective is discussed as a foundation to move beyond the dichotomous influence of the modern world view and the deconstructive critique of the post-modern perspective. The author suggests spiritual evolution and a participatory consciousness as an ontological foundation for a cosmology congruent with nursing's social mandate. © 2010 Blackwell Publishing Ltd.

Walking over 4 Gya: Chemical Evolution from Photochemistry to Mineral and Organic Chemistries Leading to an RNA World

NASA Astrophysics Data System (ADS)

Kawamura, Kunio; Maurel, Marie-Christine

2017-09-01

Here we overview the chemical evolution of RNA molecules from inorganic material through mineral-mediated RNA formation compatible with the plausible early Earth environments. Pathways from the gas-phase reaction to the formation of nucleotides, activation and oligomerization of nucleotides, seem to be compatible with specific environments. However, how these steps interacted is not clear since the chemical conditions are frequently different and can be incompatible between them; thus the products would have migrated from one place to another, suitable for further chemical evolution. In this review, we summarize certain points to scrutinize the RNA World hypothesis.

Getting Goose Bumps about Teaching Evolution

ERIC Educational Resources Information Center

Foster, Collin

2014-01-01

Evolution offers an intellectually satisfying and extremely well-supported explanation for the diversity of life in the natural world, its similarities and differences, how changes occur and how new life forms have developed. There are plenty of reasons to anticipate the teaching of evolution with exhilaration. In recent years, the issue of…

Tuition vs. Intuition: Effects of Instruction on Naive Theories of Evolution

ERIC Educational Resources Information Center

Shtulman, Andrew; Calabi, Prassede

2013-01-01

Recent research suggests that a major obstacle to evolution understanding is an essentialist view of the biological world. The present study investigated the effects of formal biology instruction on such misconceptions. Participants (N = 291) completed an assessment of their understanding of six aspects of evolution (variation, inheritance,…

Paradigms and Postmodernism in Science and Science Education.

ERIC Educational Resources Information Center

Pushkin, David B.

Science, particularly the physical sciences, has undergone several paradigm shifts during history. The modernistic and mechanistic world that was viewed through the lens of Newton's laws no longer offers valid answers to present-day questions. This paper examines four themes: the evolution of physics, the evolution of chemistry, the evolution of…

The Discovery of "Jelly Bellicus"

ERIC Educational Resources Information Center

Tieman, Deborah; Haxer, Gary

2007-01-01

To most students entering today's biology classes, evolution is something that occurred long ago, and is therefore irrelevant to their lives. Examples of evolution that are important concerns in the modern world, such as the resistance of insects to pesticides and antibiotic resistance, do not match students' concept of evolution. In this article,…

Privacy-preserving screen capture: towards closing the loop for health IT usability.

PubMed

Cooley, Joseph; Smith, Sean

2013-08-01

As information technology permeates healthcare (particularly provider-facing systems), maximizing system effectiveness requires the ability to document and analyze tricky or troublesome usage scenarios. However, real-world health IT systems are typically replete with privacy-sensitive data regarding patients, diagnoses, clinicians, and EMR user interface details; instrumentation for screen capture (capturing and recording the scenario depicted on the screen) needs to respect these privacy constraints. Furthermore, real-world health IT systems are typically composed of modules from many sources, mission-critical and often closed-source; any instrumentation for screen capture can rely neither on access to structured output nor access to software internals. In this paper, we present a tool to help solve this problem: a system that combines keyboard video mouse (KVM) capture with automatic text redaction (and interactively selectable unredaction) to produce precise technical content that can enrich stakeholder communications and improve end-user influence on system evolution. KVM-based capture makes our system both application-independent and OS-independent because it eliminates software-interface dependencies on capture targets. Using a corpus of EMR screenshots, we present empirical measurements of redaction effectiveness and processing latency to demonstrate system performances. We discuss how these techniques can translate into instrumentation systems that improve real-world health IT deployments. Copyright © 2013 Elsevier Inc. All rights reserved.

Stochastic Lotka-Volterra equations: A model of lagged diffusion of technology in an interconnected world

NASA Astrophysics Data System (ADS)

Chakrabarti, Anindya S.

2016-01-01

We present a model of technological evolution due to interaction between multiple countries and the resultant effects on the corresponding macro variables. The world consists of a set of economies where some countries are leaders and some are followers in the technology ladder. All of them potentially gain from technological breakthroughs. Applying Lotka-Volterra (LV) equations to model evolution of the technology frontier, we show that the way technology diffuses creates repercussions in the partner economies. This process captures the spill-over effects on major macro variables seen in the current highly globalized world due to trickle-down effects of technology.

Global Collective Resources: A Study of Monographic Bibliographic Records in WorldCat.

ERIC Educational Resources Information Center

Perrault, Anna H.

In 2001, WorldCat, the primary international bibliographic utility, contained 45 million records with over 750 million library location listings. These records span over 4,000 years of recorded knowledge in 377 languages. Under the auspices of an OCLC/ALISE (Online Computer Library Center/Association of Library and Information Science Educators)…

Cloning and molecular evolution of the aldehyde dehydrogenase 2 gene (Aldh2) in bats (Chiroptera).

PubMed

Chen, Yao; Shen, Bin; Zhang, Junpeng; Jones, Gareth; He, Guimei

2013-02-01

Old World fruit bats (Pteropodidae) and New World fruit bats (Phyllostomidae) ingest significant quantities of ethanol while foraging. Mitochondrial aldehyde dehydrogenase (ALDH2, encoded by the Aldh2 gene) plays an important role in ethanol metabolism. To test whether the Aldh2 gene has undergone adaptive evolution in frugivorous and nectarivorous bats in relation to ethanol elimination, we sequenced part of the coding region of the gene (1,143 bp, ~73 % coverage) in 14 bat species, including three Old World fruit bats and two New World fruit bats. Our results showed that the Aldh2 coding sequences are highly conserved across all bat species we examined, and no evidence of positive selection was detected in the ancestral branches leading to Old World fruit bats and New World fruit bats. Further research is needed to determine whether other genes involved in ethanol metabolism have been the targets of positive selection in frugivorous and nectarivorous bats.

A computational study on outliers in world music.

PubMed

Panteli, Maria; Benetos, Emmanouil; Dixon, Simon

2017-01-01

The comparative analysis of world music cultures has been the focus of several ethnomusicological studies in the last century. With the advances of Music Information Retrieval and the increased accessibility of sound archives, large-scale analysis of world music with computational tools is today feasible. We investigate music similarity in a corpus of 8200 recordings of folk and traditional music from 137 countries around the world. In particular, we aim to identify music recordings that are most distinct compared to the rest of our corpus. We refer to these recordings as 'outliers'. We use signal processing tools to extract music information from audio recordings, data mining to quantify similarity and detect outliers, and spatial statistics to account for geographical correlation. Our findings suggest that Botswana is the country with the most distinct recordings in the corpus and China is the country with the most distinct recordings when considering spatial correlation. Our analysis includes a comparison of musical attributes and styles that contribute to the 'uniqueness' of the music of each country.

A computational study on outliers in world music

PubMed Central

Benetos, Emmanouil; Dixon, Simon

2017-01-01

The comparative analysis of world music cultures has been the focus of several ethnomusicological studies in the last century. With the advances of Music Information Retrieval and the increased accessibility of sound archives, large-scale analysis of world music with computational tools is today feasible. We investigate music similarity in a corpus of 8200 recordings of folk and traditional music from 137 countries around the world. In particular, we aim to identify music recordings that are most distinct compared to the rest of our corpus. We refer to these recordings as ‘outliers’. We use signal processing tools to extract music information from audio recordings, data mining to quantify similarity and detect outliers, and spatial statistics to account for geographical correlation. Our findings suggest that Botswana is the country with the most distinct recordings in the corpus and China is the country with the most distinct recordings when considering spatial correlation. Our analysis includes a comparison of musical attributes and styles that contribute to the ‘uniqueness’ of the music of each country. PMID:29253027

Effects of the gay publishing boom on classes of titles retrieved under the subject headings "Homosexuality," "Gay Men," and "Gays" in the OCLC WorldCat database.

PubMed

Carmichael, James V

2002-01-01

What do searchers find when they look for literature on homosexuality? This question has profound implications for older as well as younger gays in their coming out, as well as in their subsequent identity development. Library records provide credible data to answer the question, since they represent relatively free sources of information, unlike data from bookstores, publishers, and some World Wide Web sites. The records of WorldCat, the world's largest union database of library records, comprise over 30 million records listed in the Online Computer Library Center. For the purposes of the study, 18,757 records listed under "Homosexuality," "Gay Men," and "Gays" were downloaded; records for "Lesbian" and "Lesbians" were not examined. Findings of the study suggest that while there has indeed been considerable growth in terms of the quantity of gay literature produced since 1969, such gains may be offset by the deteriorating quality of cataloging copy, which makes the experience of browsing records a discouraging and confusing one.

What Does "the RNA World" Mean to "the Origin of Life"?

PubMed

Ma, Wentao

2017-11-29

Corresponding to life's two distinct aspects: Darwinian evolution and self-sustainment, the origin of life should also split into two issues: the origin of Darwinian evolution and the arising of self-sustainment. Because the "self-sustainment" we concern about life should be the self-sustainment of a relevant system that is "defined" by its genetic information, the self-sustainment could not have arisen before the origin of Darwinian evolution, which was just marked by the emergence of genetic information. The logic behind the idea of the RNA world is not as tenable as it has been believed. That is, genetic molecules and functional molecules, even though not being the same material, could have emerged together in the beginning and launched the evolution-provided that the genetic molecules can "simply" code the functional molecules. However, due to these or those reasons, alternative scenarios are generally much less convincing than the RNA world. In particular, when considering the accumulating experimental evidence that is supporting a de novo origin of the RNA world, it seems now quite reasonable to believe that such a world may have just stood at the very beginning of life on the Earth. Therewith, we acquire a concrete scenario for our attempts to appreciate those fundamental issues that are involved in the origin of life. In the light of those possible scenes included in this scenario, Darwinian evolution may have originated at the molecular level, realized upon a functional RNA. When two or more functional RNAs emerged, for their efficient cooperation, there should have been a selective pressure for the emergence of protocells. But it was not until the appearance of the "unitary-protocell", which had all of its RNA genes linked into a chromosome, that Darwinian evolution made its full step towards the cellular level-no longer severely constrained by the low-grade evolution at the molecular level. Self-sustainment did not make sense before protocells emerged. The selection pressure that was favoring the exploration of more and more fundamental raw materials resulted in an evolutionary tendency of life to become more and more self-sustained. New functions for the entities to adapt to environments, including those that are involved in the self-sustainment per se, would bring new burdens to the self-sustainment-the advantage of these functions must overweigh the corresponding disadvantage.

Evolution of Medication Administration Workflow in Implementing Electronic Health Record System

ERIC Educational Resources Information Center

Huang, Yuan-Han

2013-01-01

This study focused on the clinical workflow evolutions when implementing the health information technology (HIT). The study especially emphasized on administrating medication when the electronic health record (EHR) systems were adopted at rural healthcare facilities. Mixed-mode research methods, such as survey, observation, and focus group, were…

Tidal-Rotational Dynamics of Solar System Worlds, from the Moon to Pluto

NASA Astrophysics Data System (ADS)

Keane, James Tuttle

The spins of planetary bodies are not stagnant; they evolve in response to both external and internal forces. One way a planet's spin can change is through true polar wander. True polar wander is the reorientation of a planetary body with respect to its angular momentum vector, and occurs when mass is redistributed within the body, changing its principal axes of inertia. True polar wander can literally reshape a world, and has important implications for a variety of processes--from the long-term stability of polar volatiles in the permanently shadowed regions of airless worlds like the Moon and Mercury, to the global tectonic patterns of icy worlds like Pluto. In this dissertation, we investigate three specific instances of planetary true polar wander, and their associated consequences. In Chapter 2 we investigate the classic problem of the Moon's dynamical figure. By considering the effects of a fossil figure supported by an elastic lithosphere, and the contribution of impact basins to the figure, we find that the lunar figure is consistent with the Moon's lithosphere freezing in when the Moon was much closer to the Earth, on a low eccentricity synchronous orbit. The South Pole-Aitken impact basin is the single largest perturbation to the Moon's figure and resulted in tens of degrees of true polar wander after its formation. In Chapter 3 we continue our analyses of the lunar figure in light of the discovery of a lunar "volatile" paleopole, preserved in the distribution of hydrogen near the Moon's poles. We find that the formation and evolution of the Procellarum KREEP Terrain significantly altered the Moon's orientation, implying that some fraction of the Moon's polar volatiles are ancient--predating the geologic activity within the Procellarum region. In Chapter 4 we investigate how the formation of the giant, basin-filling glacier, Sputnik Planitia reoriented Pluto. This reorientation is recorded in both the present- day location of Sputnik Planitia (near the Pluto-Charon tidal axis), and the tectonic record of Pluto. This reorientation likely reflects a coupling between Pluto's volatile cycles and rotational dynamics, and may be active on other worlds with comparably large, mobile volatile reservoirs. Finally, in Chapter 5 we consider the broader context of these studies, and touch on future investigations of true polar wander on Mercury, Venus, Mars, Vesta, Ceres, and other worlds in our solar system.

Correlated evolution of migration and sexual dichromatism in the New World orioles (icterus).

PubMed

Friedman, Nicholas R; Hofmann, Christopher M; Kondo, Beatrice; Omland, Kevin E

2009-12-01

The evolution of sexual dimorphism has long been attributed to sexual selection, specifically as it would drive repeated gains of elaborate male traits. In contrast to this pattern, New World oriole species all exhibit elaborate male plumage, and the repeated gains of sexual dichromatism observed in the genus are due to losses of female elaboration. Interestingly, most sexually dichromatic orioles belong to migratory or temperate-breeding clades. Using character scoring and ancestral state reconstructions from two recent studies in Icterus, we tested a hypothesis of correlated evolution between migration and sexual dichromatism. We employed two discrete phylogenetic comparative approaches: the concentrated changes test and Pagel's discrete likelihood test. Our results show that the evolution of these traits is significantly correlated (CCT: uncorrected P < 0.05; ML: LRT = 12.470, P < 0.005). Indeed, our best model of character evolution suggests that gains of sexual dichromatism are 23 times more likely to occur in migratory taxa. This study demonstrates that a life-history trait with no direct relationship with sexual selection has a strong influence on the evolution of sexual dichromatism. We recommend that researchers further investigate the role of selection on elaborate female traits in the evolution of sexual dimorphism.

Great Things Have Been Done by a Few Men: Operational Art in Clark’s Illinois Campaign of 1778 - 1779

DTIC Science & Technology

2011-05-19

Gruber, eds., American Military History and the Evolution of Warfare in the Western World (Lexington: D.C. Heath and Company, 1996) make no...known as St. Asaph. Ibid: James, The Life of George Rogers Clark, 56-58; Neil Hamon, Kentucky County in The Kentucky Encyclopedia, John E. Kleber...American Military History and the Evolution of Warfare in the Western World. Lexington: D.C. Heath and Company, 1996. Dunn, J.P. “The Hannibal of the

Main drivers of flood-risk dynamics along the Po River

NASA Astrophysics Data System (ADS)

Domeneghetti, Alessio; Carisi, Francesca; Castellarin, Attilio; Brath, Armando

2017-04-01

The increasing frequency with which floods damages are recorded, or reported by media, strengthen the common perception that the flood risk is dramatically increasing in Europe and other areas of the world, due to a combination of different causes, among which climate change is often described as the major factor. However, there is a growing awareness of how anthropogenic pressures, such as uncontrolled urban and industrial expansion on flood-prone areas, may strongly impact the evolution of flood-risk in a given area, increasing potential flood damages and losses. Starting from these considerations, our study aims at shedding some light on the impact and relative importance of different factors controlling the flood risk. Focusing in particular on the middle-lower portion of the River Po, we analyze the evolution of flood hazard in the last half century referring to long streamflow series for different gauging stations located along the study reach ( 450 km), while the modification of anthropogenic pressure is evaluated by referring to land-use and demographic dynamics observed from 1950s. Our study proposes simplified flood-vulnerability indices to be used for large scale flood-risk assessments and, on the basis of these indices, (1) we assess the importance of the different elements contributing to the definition of flood risk and (2) represent the evolution of flood risk in time along the middle and lower portion of the River Po.

What Hf isotopes in zircon tell us about crust-mantle evolution

NASA Astrophysics Data System (ADS)

Iizuka, Tsuyoshi; Yamaguchi, Takao; Itano, Keita; Hibiya, Yuki; Suzuki, Kazue

2017-03-01

The 176Lu-176Hf radioactive decay system has been widely used to study planetary crust-mantle differentiation. Of considerable utility in this regard is zircon, a resistant mineral that can be precisely dated by the U-Pb chronometer and record its initial Hf isotope composition due to having low Lu/Hf. Here we review zircon U-Pb age and Hf isotopic data mainly obtained over the last two decades and discuss their contributions to our current understanding of crust-mantle evolution, with emphasis on the Lu-Hf isotope composition of the bulk silicate Earth (BSE), early differentiation of the silicate Earth, and the evolution of the continental crust over geologic history. Meteorite zircon encapsulates the most primitive Hf isotope composition of our solar system, which was used to identify chondritic meteorites best representative of the BSE (176Hf/177Hf = 0.282793 ± 0.000011; 176Lu/177Hf = 0.0338 ± 0.0001). Hadean-Eoarchean detrital zircons yield highly unradiogenic Hf isotope compositions relative to the BSE, providing evidence for the development of a geochemically enriched silicate reservoir as early as 4.5 Ga. By combining the Hf and O isotope systematics, we propose that the early enriched silicate reservoir has resided at depth within the Earth rather than near the surface and may represent a fractionated residuum of a magma ocean underlying the proto-crust, like urKREEP beneath the anorthositic crust on the Moon. Detrital zircons from world major rivers potentially provide the most robust Hf isotope record of the preserved granitoid crust on a continental scale, whereas mafic rocks with various emplacement ages offer an opportunity to trace the Hf isotope evolution of juvenile continental crust (from εHf[4.5 Ga] = 0 to εHf[present] = + 13). The river zircon data as compared to the juvenile crust composition highlight that the supercontinent cycle has controlled the evolution of the continental crust by regulating the rates of crustal generation and intra-crustal reworking processes and the preservation potential of granitoid crust. We use the data to explore the timing of generation of the preserved continental crust. Taking into account the crustal residence times of continental crust recycled back into the mantle, we further propose a model of net continental growth that stable continental crust was firstly established in the Paleo- and Mesoarchean and significantly grew in the Paleoproterozoic.

The gap in the Arctic Cenozoic Record: Expect the Unexpected

NASA Astrophysics Data System (ADS)

Sangiorgi, F.; Brumsack, H.; Schouten, S.; Brinkhuis, H.; Kaminski, M. A.; Reichart, G.; Stickley, C. E.; Willard, D. A.; Sinninghe Damste', J. S.

2006-12-01

Integrated Ocean Drilling Program Expedition 302, a.k.a. the Arctic Coring Expedition (ACEX), drilled more than 400 meters below the seafloor at the central Lomonosov Ridge, ca 250 km from the modern North Pole in water depths of about 1300 m. The partially recovered sediments provide a unique record of the geological and paleoceanographical evolution of the Arctic Ocean during the Cenozoic. The record indicates a transition from a "greenhouse world", characterized by a relative shallow marine setting, with organic-rich sediment and frequent brackish or even fresh surface waters during the latest Palaeocene and the early Eocene, to an "icehouse world" of hemipelagic sedimentation affected by the occurrence of sea ice from the middle Miocene to present. Much to our surprise, these two states are separated by a major hiatus, not obvious from the seismic record and the lithology of the cores, spanning at least 25 Ma as derived from dinocyst and benthic foraminifer stratigraphies. These testify that deposits of probable late early Miocene age directly overlie early middle Eocene sediments. To unravel the nature of the hiatus, we performed a multiproxy micropaleontological and geochemical study on the surrounding record, i.e. lithological units 1/6, 1/5 and 1/4, where the sediment changes from homogeneous dark into a cm-scaled alternation ("zebra-like") black and grey bands to light grey, blue and reddish-brown. Paleoenvironmental reconstructions based on organic-walled dinoflagellate cysts, pollen and spores, benthic foraminifera, inorganic and organic geochemistry and siliceous remains reveal conspicuous changes, suggesting a transition from brackish-freshwater to shallow-lagoonal and to open marine environments. These environmental turnovers, coupled with the occurrence of such a large hiatus, cannot be due to climatic shifts alone, but suggest that major tectonic rearrangements likely changed the depositional setting. On-going organic geochemical analysis will be used to constrain the climatic and environmental changes throughout the studied interval in terms of quantified temperature changes (TEX86), relative variations in freshwater input (BIT) and in water column oxygenation (oxic vs. euxinic conditions).

A missing link in the evolution of the cumulative recorder.

PubMed

Asano, Toshio; Lattal, Kennon A

2012-09-01

A recently recovered cumulative recorder provides a missing link in the evolution of the cumulative recorder from a modified kymograph to a reliably operating, scientifically and commercially successful instrument. The recorder, the only physical evidence of such an early precommercial cumulative recorder yet found, was sent to Keio University in Tokyo, Japan, in 1952 at the behest of B. F. Skinner at Harvard University. Last used in research in the late 1960s, the cumulative recorder remained locked in a storage room until 2007, when it was found again. A historical context for the recorder is followed by a description of the recorder and a comparison between it and the commercially successful Gerbrands Model C-1 recorder. Labeled the Keio recorder, it is a testament to Skinner's persistence in developing a reliable means of quantifying the behavior of living organisms in real time.

Plio-Pleistocene time evolution of the 100-ky cycle in marine paleoclimate records

NASA Technical Reports Server (NTRS)

Park, Jeffrey; Maasch, Kirk A.

1992-01-01

To constrain theories for the dynamical evolution of global ice mass through the late Neogene, it is important to determine whether major changes in the record were gradual or rapid. Of particular interest is the evolution of the near 100-ky ice age cycle in the middle Pleistocene. We have applied a new technique based on multiple taper spectrum analysis which allows us to model the time evolution of quasi-periodic signals. This technique uses both phase and amplitude information, and enables us to address the question of abrupt versus gradual onset of the 100-ky periodicity in the middle Pleistocene.

The New World Gibbobruchus Pic (Coleoptera, Chrysomelidae, Bruchinae): description of a new species and phylogenetic insights into the evolution of host associations and biogeography.

PubMed

Manfio, Daiara; Jorge, Isaac R; Morse, Geoffrey E; Ribeiro-Costa, Cibele S

2016-04-18

The seed beetle Gibbobruchus tridentatus Manfio, Jorge & Ribeiro-Costa sp. nov. is described from the Amazon basin in Brazil (Acre) and Ecuador (Napo), and is included in an updated key to the species of Gibbobruchus Pic. This new species and the recently described G. bergamini Manfio & Ribeiro-Costa are incorporated into a phylogenetic reanalysis of the genus and into a comparative analysis of host plant use and biogeography. Species groups previously proposed were supported and the evolutionary history in host plant-use shows Gibbobruchus conserved at tribe level, Cercideae (Caesalpinioideae), with coordination between biogeographic expansion and host genus shifts. Both species, Gibbobruchus tridentatus Manfio, Jorge & Ribeiro-Costa sp. nov. and G. bergamini, were placed within the group scurra (G. tridentatus (G. scurra (G. cavillator+G. bolivianus+G. bergamini))) and supported by one synapomorphy. Additionally, we update geographic distributions and host plant records. Two hosts, Bauhinia argentinensis Burkart and B. tarapotensis Benth. are recorded for the first time as hosts for the genus and for the subfamily.

Investing in health information management: The right people, in the right place, at the right time.

PubMed

Ayodeji Makinde, Olusesan; Mami, Mohammed Ibrahim; Oweghoro, Benson Macaulay; Oyediran, Kolawole Azeez; Mullen, Stephanie

2016-08-01

To describe the process adopted to review the academic curriculum for training health information management professionals in Nigeria. Health information management professionals are responsible for managing patients' health service records and hospital information systems across health facilities in Nigeria. An assessment found many are inadequately skilled in information and communications technology (ICT) skills believed to be needed for them to play leadership roles in hospital information systems and function effectively. This was traced to a dearth of relevant ICT courses in their academic training curriculum. A review of the curriculum for training health information management professionals was instituted following an agreed need to address these issues. Health records management is evolving across the world including the developing countries. This advancement requires evolution of training programs to meet the increasing application of ICT in this sector. After several sessions, a new curriculum that addresses all the identified educational deficiencies has been developed. It is believed that this step will help improve the quality of training programs. © The Author(s) 2016.

Arctic Sea Ice in a 1.5°C Warmer World

NASA Astrophysics Data System (ADS)

Niederdrenk, Anne Laura; Notz, Dirk

2018-02-01

We examine the seasonal cycle of Arctic sea ice in scenarios with limited future global warming. To do so, we analyze two sets of observational records that cover the observational uncertainty of Arctic sea ice loss per degree of global warming. The observations are combined with 100 simulations of historical and future climate evolution from the Max Planck Institute Earth System Model Grand Ensemble. Based on the high-sensitivity observations, we find that Arctic September sea ice is lost with low probability (P≈ 10%) for global warming of +1.5°C above preindustrial levels and with very high probability (P> 99%) for global warming of +2°C above preindustrial levels. For the low-sensitivity observations, September sea ice is extremely unlikely to disappear for +1.5°C warming (P≪ 1%) and has low likelihood (P≈ 10%) to disappear even for +2°C global warming. For March, both observational records suggest a loss of 15% to 20% of Arctic sea ice area for 1.5°C to 2°C global warming.

Knowing the Natural World: The Construction of Knowledge about Evolution in and out of the Classroom

ERIC Educational Resources Information Center

Perkins, Alison Emily Havard

2009-01-01

Evolution is a central underlying concept to a significant number of discourses in civilized society, but the complexity of understanding basic tenets of this important theory is just now coming to light. Knowledge about evolution is constructed from both formal and "free-choice" opportunities, like television. Nature programs are commonly…

The glycogen synthase 2 gene (Gys2) displays parallel evolution between Old World and New World fruit bats.

PubMed

Qian, Yamin; Fang, Tao; Shen, Bin; Zhang, Shuyi

2014-01-01

Frugivorous and nectarivorous bats rely largely on hepatic glycogenesis and glycogenolysis for postprandial blood glucose disposal and maintenance of glucose homeostasis during short time starvation, respectively. The glycogen synthase 2 encoded by the Gys2 gene plays a critical role in liver glycogen synthesis. To test whether the Gys2 gene has undergone adaptive evolution in bats with carbohydrate-rich diets in relation to their insect-eating sister taxa, we sequenced the coding region of the Gys2 gene in a number of bat species, including three Old World fruit bats (OWFBs) (Pteropodidae) and two New World fruit bats (NWFBs) (Phyllostomidae). Our results showed that the Gys2 coding sequences are highly conserved across all bat species we examined, and no evidence of positive selection was detected in the ancestral branches leading to OWFBs and NWFBs. Our explicit convergence test showed that posterior probabilities of convergence between several branches of OWFBs, and the NWFBs were markedly higher than that of divergence. Three parallel amino acid substitutions (Q72H, K371Q, and E666D) were detected among branches of OWFBs and NWFBs. Tests for parallel evolution showed that two parallel substitutions (Q72H and E666D) were driven by natural selection, while the K371Q was more likely to be fixed randomly. Thus, our results suggested that the Gys2 gene has undergone parallel evolution on amino acid level between OWFBs and NWFBs in relation to their carbohydrate metabolism.

The Evolution of Design

ERIC Educational Resources Information Center

Stebbins, G. Ledyard

1973-01-01

Describes the basic logic behind the modern view of evolution theory. Despite gaps in fossil records, evidence is indicative of the origin of life from nonliving molecules and evolution of higher forms of life from simpler forms. (PS)

The "War Poets": Evolution of a Literary Conscience in World War I.

ERIC Educational Resources Information Center

Galambos, Ellen

1983-01-01

Pre-World War I poetry often used picturesque images which blinded people to the actual horrors of war. The war poets, who experienced the destruction of World War I, led the way in expressing new images of the devastation and death of war, rather than focusing on honor and glory. (IS)

Is evolutionary history repeatedly rewritten in light of new fossil discoveries?

PubMed

Tarver, J E; Donoghue, P C J; Benton, M J

2011-02-22

Mass media and popular science journals commonly report that new fossil discoveries have 'rewritten evolutionary history'. Is this merely journalistic hyperbole or is our sampling of systematic diversity so limited that attempts to derive evolutionary history from these datasets are premature? We use two exemplars-catarrhine primates (Old World monkeys and apes) and non-avian dinosaurs-to investigate how the maturity of datasets can be assessed. Both groups have been intensively studied over the past 200 years and so should represent pinnacles in our knowledge of vertebrate systematic diversity. We test the maturity of these datasets by assessing the completeness of their fossil records, their susceptibility to changes in macroevolutionary hypotheses and the balance of their phylogenies through study time. Catarrhines have shown prolonged stability, with discoveries of new species being evenly distributed across the phylogeny, and thus have had little impact on our understanding of their fossil record, diversification and evolution. The reverse is true for dinosaurs, where the addition of new species has been non-random and, consequentially, their fossil record, tree shape and our understanding of their diversification is rapidly changing. The conclusions derived from these analyses are relevant more generally: the maturity of systematic datasets can and should be assessed before they are exploited to derive grand macroevolutionary hypotheses.

Workshop on Early Crustal Genesis: The World's Oldest Rocks

NASA Technical Reports Server (NTRS)

Ashwal, L. D. (Editor)

1986-01-01

Topics addressed include: a general review of Precambrain crustal evolution; geology and geochemistry of the Archean Craton in Greenland and Labrador; Precambrian crustal evolution in North and South America; and the field excursion to the Ameralik Fjord.

Interpreting Evidence: An Approach to Teaching Human Evolution in the Classroom

ERIC Educational Resources Information Center

DeSilva, Jeremy

2004-01-01

Paleoanthropology, which is the study of human evolution through fossil records, can be used as a tool for teaching human evolution in the classrooms. An updated approach to teaching human evolution and a model for explaining what is science and how it is done, is presented.

Small Theropod Teeth from the Late Cretaceous of the San Juan Basin, Northwestern New Mexico and Their Implications for Understanding Latest Cretaceous Dinosaur Evolution

PubMed Central

Williamson, Thomas E.; Brusatte, Stephen L.

2014-01-01

Studying the evolution and biogeographic distribution of dinosaurs during the latest Cretaceous is critical for better understanding the end-Cretaceous extinction event that killed off all non-avian dinosaurs. Western North America contains among the best records of Late Cretaceous terrestrial vertebrates in the world, but is biased against small-bodied dinosaurs. Isolated teeth are the primary evidence for understanding the diversity and evolution of small-bodied theropod dinosaurs during the Late Cretaceous, but few such specimens have been well documented from outside of the northern Rockies, making it difficult to assess Late Cretaceous dinosaur diversity and biogeographic patterns. We describe small theropod teeth from the San Juan Basin of northwestern New Mexico. These specimens were collected from strata spanning Santonian – Maastrichtian. We grouped isolated theropod teeth into several morphotypes, which we assigned to higher-level theropod clades based on possession of phylogenetic synapomorphies. We then used principal components analysis and discriminant function analyses to gauge whether the San Juan Basin teeth overlap with, or are quantitatively distinct from, similar tooth morphotypes from other geographic areas. The San Juan Basin contains a diverse record of small theropods. Late Campanian assemblages differ from approximately co-eval assemblages of the northern Rockies in being less diverse with only rare representatives of troodontids and a Dromaeosaurus-like taxon. We also provide evidence that erect and recurved morphs of a Richardoestesia-like taxon represent a single heterodont species. A late Maastrichtian assemblage is dominated by a distinct troodontid. The differences between northern and southern faunas based on isolated theropod teeth provide evidence for provinciality in the late Campanian and the late Maastrichtian of North America. However, there is no indication that major components of small-bodied theropod diversity were lost during the Maastrichtian in New Mexico. The same pattern seen in northern faunas, which may provide evidence for an abrupt dinosaur extinction. PMID:24709990

Small theropod teeth from the Late Cretaceous of the San Juan Basin, northwestern New Mexico and their implications for understanding latest Cretaceous dinosaur evolution.

PubMed

Williamson, Thomas E; Brusatte, Stephen L

2014-01-01

Studying the evolution and biogeographic distribution of dinosaurs during the latest Cretaceous is critical for better understanding the end-Cretaceous extinction event that killed off all non-avian dinosaurs. Western North America contains among the best records of Late Cretaceous terrestrial vertebrates in the world, but is biased against small-bodied dinosaurs. Isolated teeth are the primary evidence for understanding the diversity and evolution of small-bodied theropod dinosaurs during the Late Cretaceous, but few such specimens have been well documented from outside of the northern Rockies, making it difficult to assess Late Cretaceous dinosaur diversity and biogeographic patterns. We describe small theropod teeth from the San Juan Basin of northwestern New Mexico. These specimens were collected from strata spanning Santonian - Maastrichtian. We grouped isolated theropod teeth into several morphotypes, which we assigned to higher-level theropod clades based on possession of phylogenetic synapomorphies. We then used principal components analysis and discriminant function analyses to gauge whether the San Juan Basin teeth overlap with, or are quantitatively distinct from, similar tooth morphotypes from other geographic areas. The San Juan Basin contains a diverse record of small theropods. Late Campanian assemblages differ from approximately coeval assemblages of the northern Rockies in being less diverse with only rare representatives of troodontids and a Dromaeosaurus-like taxon. We also provide evidence that erect and recurved morphs of a Richardoestesia-like taxon represent a single heterodont species. A late Maastrichtian assemblage is dominated by a distinct troodontid. The differences between northern and southern faunas based on isolated theropod teeth provide evidence for provinciality in the late Campanian and the late Maastrichtian of North America. However, there is no indication that major components of small-bodied theropod diversity were lost during the Maastrichtian in New Mexico. The same pattern seen in northern faunas, which may provide evidence for an abrupt dinosaur extinction.

Role of the multinational corporations in Nigeria's development

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

Okonkwo, P.A.

1978-01-01

A dominant characteristic of the decades immediately following World War II is the evolution of the multinational corporation. This evolution necessitated a change in the perspective of the international companies. The survival of the multinational corporations depended on its world profit perspective. Initially, the European countries provided the American multinational with world trade avenues while the European multinationals established subsidiaries in Africa. Recently, both the American and the European subsidiares have become interested in Nigeria because of its prospect as a potential market in Africa. The major objective of the research is to inquire about executive judgements and decision criteriamore » for marketing mix considerations and decisions. Also because of the uniqueness of Nigeria from the Western World in terms of its socio-cultural, legal, economic and political environments,executive decision criteria in the area of manufacturing was also investigated.« less

Evolution in the Southeastern USA: Factors Influencing Acceptance and Rejection in Pre-Service Science Teachers

ERIC Educational Resources Information Center

Glaze, Amanda L.; Goldston, M. Jenice; Dantzler, John

2015-01-01

Evolution continues to be a controversial topic around the world but nowhere is this more apparent locally than in the Southeastern region of the USA. In this study, we explored acceptance and rejection of evolution among pre-service science teachers in a teaching college in the rural Southeast and sought to determine (1) what relationships exist…

Evolution of community structure in the world trade web

NASA Astrophysics Data System (ADS)

Tzekina, I.; Danthi, K.; Rockmore, D. N.

2008-06-01

In this note we study the bilateral merchandise trade flows between 186 countries over the 1948 2005 period using data from the International Monetary Fund. We use the network visualization package Pajek to identify network structure and behavior across thresholds and over time. In particular, we focus on the evolution of trade “islands” in a world trade network in which countries are linked with directed edges weighted according to the fraction of total dollars sent from one country to another. We find mixed evidence for globalization.

The role of play objects and object play in human cognitive evolution and innovation.

PubMed

Riede, Felix; Johannsen, Niels N; Högberg, Anders; Nowell, April; Lombard, Marlize

2018-01-01

In this contribution, we address a major puzzle in the evolution of human material culture: If maturing individuals just learn their parental generation's material culture, then what is the origin of key innovations as documented in the archeological record? We approach this question by coupling a life-history model of the costs and benefits of experimentation with a niche-construction perspective. Niche-construction theory suggests that the behavior of organisms and their modification of the world around them have important evolutionary ramifications by altering developmental settings and selection pressures. Part of Homo sapiens' niche is the active provisioning of children with play objects - sometimes functional miniatures of adult tools - and the encouragement of object play, such as playful knapping with stones. Our model suggests that salient material culture innovation may occur or be primed in a late childhood or adolescence sweet spot when cognitive and physical abilities are sufficiently mature but before the full onset of the concerns and costs associated with reproduction. We evaluate the model against a series of archeological cases and make suggestions for future research. © 2018 The Authors Evolutionary Anthropology Published by Wiley Periodicals, Inc.

Earliest colobine skeletons from Nakali, Kenya.

PubMed

Nakatsukasa, Masato; Mbua, Emma; Sawada, Yoshihiro; Sakai, Tetsuya; Nakaya, Hideo; Yano, Wataru; Kunimatsu, Yutaka

2010-11-01

Old World monkeys represent one of the most successful adaptive radiations of modern primates, but a sparse fossil record has limited our knowledge about the early evolution of this clade. We report the discovery of two partial skeletons of an early colobine monkey (Microcolobus) from the Nakali Formation (9.8-9.9 Ma) in Kenya that share postcranial synapomorphies with extant colobines in relation to arboreality such as mediolaterally wide distal humeral joint, globular humeral capitulum, distinctly angled zona conoidea, reduced medial trochlear keel, long medial epicondyle with weak retroflexion, narrow and tall olecranon, posteriorly dislocated fovea on the radial head, low projection of the femoral greater trochanter, wide talar head with a greater rotation, and proximodistally short cuboid and ectocuneiform. Microcolobus in Nakali clearly differs from the stem cercopithecoid Victoriapithecus regarding these features, as Victoriapithecus is postcranially similar to extant small-sized terrestrial cercopithecines. However, degeneration of the thumb, a hallmark of modern colobines, is not observed, suggesting that this was a late event in colobine evolution. This discovery contradicts the prevailing hypothesis that the forest invasion by cercopithecids first occurred in the Plio-Pleistocene, and shows that this event occurred by the late Miocene at a time when ape diversity declined. © 2010 Wiley-Liss, Inc.

Geomagnetic dipole strength and reversal rate over the past two million years.

PubMed

Valet, Jean-Pierre; Meynadier, Laure; Guyodo, Yohan

2005-06-09

Independent records of relative magnetic palaeointensity from sediment cores in different areas of the world can be stacked together to extract the evolution of the geomagnetic dipole moment and thus provide information regarding the processes governing the geodynamo. So far, this procedure has been limited to the past 800,000 years (800 kyr; ref. 3), which does not include any geomagnetic reversals. Here we present a composite curve that shows the evolution of the dipole moment during the past two million years. This reconstruction is in good agreement with the absolute dipole moments derived from volcanic lavas, which were used for calibration. We show that, at least during this period, the time-averaged field was higher during periods without reversals but the amplitude of the short-term oscillations remained the same. As a consequence, few intervals of very low intensity, and thus fewer instabilities, are expected during periods with a strong average dipole moment, whereas more excursions and reversals are expected during periods of weak field intensity. We also observe that the axial dipole begins to decay 60-80 kyr before reversals, but rebuilds itself in the opposite direction in only a few thousand years.

Multiple-try differential evolution adaptive Metropolis for efficient solution of highly parameterized models

NASA Astrophysics Data System (ADS)

Eric, L.; Vrugt, J. A.

2010-12-01

Spatially distributed hydrologic models potentially contain hundreds of parameters that need to be derived by calibration against a historical record of input-output data. The quality of this calibration strongly determines the predictive capability of the model and thus its usefulness for science-based decision making and forecasting. Unfortunately, high-dimensional optimization problems are typically difficult to solve. Here we present our recent developments to the Differential Evolution Adaptive Metropolis (DREAM) algorithm (Vrugt et al., 2009) to warrant efficient solution of high-dimensional parameter estimation problems. The algorithm samples from an archive of past states (Ter Braak and Vrugt, 2008), and uses multiple-try Metropolis sampling (Liu et al., 2000) to decrease the required burn-in time for each individual chain and increase efficiency of posterior sampling. This approach is hereafter referred to as MT-DREAM. We present results for 2 synthetic mathematical case studies, and 2 real-world examples involving from 10 to 240 parameters. Results for those cases show that our multiple-try sampler, MT-DREAM, can consistently find better solutions than other Bayesian MCMC methods. Moreover, MT-DREAM is admirably suited to be implemented and ran on a parallel machine and is therefore a powerful method for posterior inference.

Globalisation of inflammatory bowel disease: perspectives from the evolution of inflammatory bowel disease in the UK and China.

PubMed

Kaplan, Gilaad G; Ng, Siew C

2016-12-01

The UK and China provide unique historical perspectives on the evolution of the incidence of inflammatory bowel disease, which might provide insight into its pathogenesis. Historical records from the UK document the emergence of ulcerative colitis during the mid-1800s, which was later followed by the recognition of Crohn's disease in 1932. During the second half of the 20th century, the incidence of inflammatory bowel disease rose dramatically in high-income countries. Globalisation at the turn of the 21st century led to rapid economic development of newly industrialised countries such as China. In China, the modernisation of society was accompanied by the recognition of a sharp rise in the incidence of inflammatory bowel disease. The prevalence of inflammatory bowel disease is expected to continue to rise in high-income countries and is also likely to accelerate in the developing world. An understanding of the shared and different environmental determinants underpinning the pathogenesis of inflammatory bowel disease in western and eastern countries is essential to implement interventions that will blunt the rising global burden of inflammatory bowel disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

Cooperative inference: Features, objects, and collections.

PubMed

Searcy, Sophia Ray; Shafto, Patrick

2016-10-01

Cooperation plays a central role in theories of development, learning, cultural evolution, and education. We argue that existing models of learning from cooperative informants have fundamental limitations that prevent them from explaining how cooperation benefits learning. First, existing models are shown to be computationally intractable, suggesting that they cannot apply to realistic learning problems. Second, existing models assume a priori agreement about which concepts are favored in learning, which leads to a conundrum: Learning fails without precise agreement on bias yet there is no single rational choice. We introduce cooperative inference, a novel framework for cooperation in concept learning, which resolves these limitations. Cooperative inference generalizes the notion of cooperation used in previous models from omission of labeled objects to the omission values of features, labels for objects, and labels for collections of objects. The result is an approach that is computationally tractable, does not require a priori agreement about biases, applies to both Boolean and first-order concepts, and begins to approximate the richness of real-world concept learning problems. We conclude by discussing relations to and implications for existing theories of cognition, cognitive development, and cultural evolution. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Software Architecture Evolution

ERIC Educational Resources Information Center

Barnes, Jeffrey M.

2013-01-01

Many software systems eventually undergo changes to their basic architectural structure. Such changes may be prompted by new feature requests, new quality attribute requirements, changing technology, or other reasons. Whatever the causes, architecture evolution is commonplace in real-world software projects. Today's software architects, however,…

The Collisional Evolution of the Main Asteroid Belt

NASA Astrophysics Data System (ADS)

Bottke, W. F.; Brož, M.; O'Brien, D. P.; Campo Bagatin, A.; Morbidelli, A.; Marchi, S.

Collisional and dynamical models of the main asteroid belt allow us to glean insights into planetesimal- and planet-formation scenarios as well as how the main belt reached its current state. Here we discuss many of the processes affecting asteroidal evolution and the constraints that can be used to test collisional model results. We argue the main belt's wavy size-frequency distribution for diameter D < 100-km asteroids is increasingly a byproduct of comminution as one goes to smaller sizes, with its shape a fossil-like remnant of a violent early epoch. Most D > 100-km asteroids, however, are primordial, with their physical properties set by planetesimal formation and accretion processes. The main-belt size distribution as a whole has evolved into a collisional steady state, and it has possibly been in that state for billions of years. Asteroid families provide a critical historical record of main-belt collisions. The heavily depleted and largely dispersed "ghost families," however, may hold the key to understanding what happened in the primordial days of the main belt. New asteroidal fragments are steadily created by both collisions and mass shedding events via YORP spinup processes. A fraction of this population, in the form of D < 30 km fragments, go on to escape the main belt via the Yarkovsky/YORP effects and gravitational resonances, thereby creating a quasi-steady-state population of planet-crossing and near-Earth asteroids. These populations go on to bombard all inner solar system worlds. By carefully interpreting the cratering records they produce, it is possible to constrain how portions of the main-belt population have evolved with time.

High-resolution DEMs for High-mountain Asia: A systematic, region-wide assessment of geodetic glacier mass balance and dynamics

NASA Astrophysics Data System (ADS)

Shean, D. E.; Arendt, A. A.; Osmanoglu, B.; Montesano, P.

2017-12-01

High Mountain Asia (HMA) constitutes the largest glacierized region outside of the Earth's polar regions. Although available observations are limited, long-term records indicate sustained regional glacier mass loss since 1850, with increased loss in recent decades. Recent satellite data (e.g., GRACE, ICESat-1) show spatially variable glacier mass balance, with significant mass loss in the Himalaya and Hindu Kush and slight mass gain in the Karakoram. We generated 4000 high-resolution digital elevation models (DEMs) from sub-meter commercial stereo imagery (DigitalGlobe WorldView/GeoEye) acquired over glaciers in High-mountain Asia from 2002-present (mostly 2013-present). We produced a regional 8-m DEM mosaic for 2015 and estimated 15-year geodetic mass balance for 40000 glaciers larger than 0.1 km2. We are combining with other regional DEM sources to systematically document the spatiotemporal evolution of glacier mass balance for the entire HMA region. We also generated monthly to interannual DEM and velocity time series for high-priority sites distributed across the region, with >15-20 DEMs available for some locations from 2010-present. These records document glacier dynamics, seasonal snow accumulation/redistribution, and processes that affect glacier mass balance (e.g., ice-cliff retreat, debris cover evolution). These efforts will provide basin-scale assessments of snow/ice melt runoff contributions for model cal/val and downstream water resources applications. We will continue processing all archived and newly available commercial stereo imagery for HMA, and will release all DEMs through the HiMAT DAAC.

Nontherapeutic quality improvement: The conflict of organizational ethics and societal rule of law.

PubMed

Rie, Michael A; Kofke, W Andrew

2007-02-01

Critical care ethics focuses largely on patient autonomy. Cost containment is necessary but requires rationing and limitations on a patient's right to consume beneficial services. No laws address a process of autonomy rights limitation to consume resources in the intensive care unit. We analyzed the frictional interface between necessary cost containment as a quality improvement activity contrasted with individual autonomy in the context of the evolution of research ethics. Scholarly books, peer-reviewed articles, congressional record, legal sources, the World Wide Web, and the National Archives and Records Administration were evaluated in the context of current cost-containment-driven nontherapeutic quality improvement activities. Three generations in the evolution of human research ethics are identified: 1) Hippocrates to Nuremberg Code, 2) Nuremberg to Belmont, and 3) Belmont to present. Similar ethical lapses, which place the individual at risk without disclosure for the good of future patients, have arisen recurrently in the course of history and continue presently when nontherapeutic quality improvement activities are framed as a human research activity with essentially no ethical oversight. Consequently, fiduciary obligations of professionals and their employer-institutions to their mutual patients may be at odds, creating complex layers of conflicted decision making. Nonetheless, professional Hippocratic duty to "the patient" must be congruent with the organizational ethos of limited funding "stewardship" to produce meaningful patient care. Medicine's integrity is legally protected and mandated under the state interests (parens patria doctrine) of the common law. When hospitals (society and its health insurance methods) fail to ration transparently under "cost-containment ethics," they threaten the ethical integrity of the medical profession.

Evolution of the Whipple procedure at the Massachusetts General Hospital.

PubMed

Fernández-del Castillo, Carlos; Morales-Oyarvide, Vicente; McGrath, Deborah; Wargo, Jennifer A; Ferrone, Cristina R; Thayer, Sarah P; Lillemoe, Keith D; Warshaw, Andrew L

2012-09-01

Since Allen O. Whipple published his seminal paper in 1935, the procedure that bears his name has been performed widely throughout the world and is now a common operation in major medical centers. The goal of this study was to investigate the evolution of pancreatoduodenectomy at the Massachusetts General Hospital (MGH). We sought to identify all pancreatoduodenectomies performed at the MGH since 1935. Cases were obtained from a computerized database, hospital medical records, and the MGH historical archive. Demographics, diagnosis, intraoperative variables and short-term surgical outcomes were recorded. The first pancreatoduodenectomy at the MGH was carried out in 1941; since then, 2,050 Whipple procedures have been performed. Pancreatic ductal adenocarcinoma was the most frequent indication (36%). Pylorus preservation has been the most important variation in technique, accounting for 45% of Whipple procedures in the 1980s; observation of frequent delayed gastric emptying after this procedure led to decline in its use. Pancreatic fistula was the most frequent complication (13%). Operative blood replacement and reoperation rates have decreased markedly over time; the most frequent indication for reoperation was intra-abdominal bleeding. Mortality has decreased from 45% to 0.8%, with sepsis and hypovolemic shock being the most frequent causes of death. Mean duration of hospital stay has decreased from >30 to 9.5 days, along with an increasing readmission rate (currently 19%). The Whipple procedure in the 21st century is a well-established operation. Improvements in operative technique and perioperative care have contributed in making it a safe operation that continues evolving. Copyright © 2012 Mosby, Inc. All rights reserved.

World elder abuse awareness day: the concept, the reality, and the promise.

PubMed

Merriman-Nai, Sharon; Stein, Karen

2014-01-01

This commentary traces the origins and evolution of the World Elder Abuse Awareness Day (WEAAD) initiative and provides recommendations for increasing WEAAD's impact as a catalyst for a coordinated movement within the United States.

Explanatory Parent-Child Conversation Predominates at an Evolution Exhibit

ERIC Educational Resources Information Center

Tare, Medha; French, Jason; Frazier, Brandy N.; Diamond, Judy; Evans, E. Margaret

2011-01-01

To investigate how parents support children's learning at an exhibit on evolution, the conversations of 12 families were recorded, transcribed, and coded (6,263 utterances). Children (mean age 9.6 years) and parents visited Explore Evolution, which conveyed current research about the evolution of seven organisms. Families were engaged with the…

The early evolution of eukaryotes - A geological perspective

NASA Technical Reports Server (NTRS)

Knoll, Andrew H.

1992-01-01

This paper examines the goodness of fit between patterns of biological and environmental history implied by molecular phylogenies of eukaryotic organisms and the geological records of early eukaryote evolution. It was found that Precambrian geological records show evidence that episodic increases in biological diversity roughly coincided with episodic environmental changes and by sharp increases in atmospheric oxygen concentrations which significantly changed the earth surface environments. Although the goodness of fit among physical and biological changes is gratifyingly high, the records of these changes do not always coincide in time. The additional information in these fields that is needed for complete integration of geological and phylogenic records is suggested.

The Evolution of Constructivist Learning Environments: Immersion in Distributed, Virtual Worlds.

ERIC Educational Resources Information Center

Dede, Chris

1995-01-01

Discusses the evolution of constructivist learning environments and examines the collaboration of simulated software models, virtual environments, and evolving mental models via immersion in artificial realities. A sidebar gives a realistic example of a student navigating through cyberspace. (JMV)

[Darwin and bacteria].

PubMed

Ledermann D, Walter

2009-02-01

As in 2009 the scientific world celebrates two hundreds years from the birthday of Charles Darwin and one hundred and fifty from the publication of The Origin of Species, an analysis of his complete work is performed, looking for any mention of bacteria. But it seems that the great naturahst never took knowledge about its existence, something rather improbable in a time when the discovery of bacteria shook the medical world, or he deliberately ignored them, not finding a place for such microscopic beings into his theory of evolution. But the bacteria badly affected his familiar life, killing scarlet fever one of his children and worsening to death the evolution of tuberculosis of his favourite Annie. Darwin himself could suffer the sickness of Chagas, whose etiological agent has a similar level to bacteria in the scale of evolution.

Optimal race strategy for a 200-m flying sprint in a human-powered vehicle: A case study of a world-record attempt.

PubMed

de Koning, Jos J; van der Zweep, Cees-Jan; Cornelissen, Jesper; Kuiper, Bouke

2013-03-01

Optimal pacing strategy was determined for breaking the world speed record on a human-powered vehicle (HPV) using an energy-flow model in which the rider's physical capacities, the vehicle's properties, and the environmental conditions were included. Power data from world-record attempts were compared with data from the model, and race protocols were adjusted to the results from the model. HPV performance can be improved by using an energy-flow model for optimizing race strategy. A biphased in-run followed by a sprint gave best results.

The Global Historical Climatology Network: Long-Term Monthly Temperature, Precipitation, Sea Level Pressure, and Station Pressure Data (NDP-041)

DOE Data Explorer

Vose, Russell S. [Carbon Dioxide Information Analysis Center (CDIAC),; Schmoyer, Richard L.; Steurer, Peter M. [National Oceanic and Atmospheric Administration (NOAA), National Climatic Data Center, Asheville, NC (USA); Peterson, Thomas C. [National Oceanic and Atmospheric Administration (NOAA), National Climatic Data Center, Asheville, NC (USA); Heim, Richard [National Oceanic and Atmospheric Administration (NOAA), National Climatic Data Center, Asheville, NC (USA); Karl, Thomas R. [National Oceanic and Atmospheric Administration (NOAA), National Climatic Data Center, Asheville, NC (USA); Eischeid, Jon K. [Cooperative Institute for Research in Environmental Sciences, Boulder, CO (USA)

1992-01-01

The GHCN data base contains mean monthly temperature data (in tenths of degrees celsius) for 6039 stations throughout the world. The majority (61%) have records for fewer than 50 years, but a significant proportion (10%) have records in excess of 100 years. It also contains total monthly precipitation data (in tenths of millimeters) for 7533 stations throughout the world. A slight majority (55%) have records in excess of 50 years, and a significant proportion (13%) have records in excess of 100 years. Also in this content is mean monthly sea level pressure data (in tenths of millibars) for 1883 stations throughout the world. The monthly station pressure data from those stations is also available here.

Mars’ First Billion Years: Key Findings, Key Unsolved Paradoxes, and Future Exploration

NASA Astrophysics Data System (ADS)

Ehlmann, Bethany

2017-10-01

In the evolution of terrestrial planets, the first billion years are the period most shrouded in mystery: How vigorous is early atmospheric loss? How do planetary climates respond to a brightening sun? When and how are plate tectonic recycling processes initiated? How do voluminous volcanism and heavy impact bombardment influence the composition of the atmosphere? Under what conditions might life arise? Looking outward to terrestrial planets around other stars, the record from Venus, Earth and Mars in this solar system is crucial for developing models of physical can chemical processes. Of these three worlds, Mars provides the longest record of planetary evolution from the first billion years, comprising >50% of exposed geologic units, which are only lightly overprinted by later processes.Orbital observations of the last decade have revealed abundant evidence for surface waters in the form of lakes, valley networks, and evidence of chemically open-system near-surface weathering. Groundwaters at temperatures ranging from just above freezing to hydrothermal have also left a rich record of process in the mineralogical record. A rsuite of environments - similar in diversity to Earth’s - has been discovered on Mars with water pH, temperature, redox, and chemistries varying in space and time.Here, I will focus on the consequences of the aqueous alteration of the Martian crust on the composition of the atmosphere based on recent work studying aspects of the volatile budget (Usui et al., 2015; Edwards & Ehlmann, 2015; Hu et al., 2015; Jakosky et al., 2017, Wordsworth et al., 2017, and Ehlmann, in prep.). The solid crust and mantle of Mars act as volatile reservoirs and volatile sources through volcanism, mineral precipitation, and release of gases. We examine the extent to which the budget is understood or ill-understood for hydrogen and carbon, and associated phases H2O, CO2, and CH4. Additionally, I identify some key stratigraphies where a combination of focused in situ analyses and/or sample return can answer questions about the response of the atmosphere -- and thus Mars climate -- to endogenous and exogenous planetary processes active during the first billion years.

Cofactors in the RNA World

NASA Technical Reports Server (NTRS)

Ditzler, Mark A.

2014-01-01

RNA world theories figure prominently in many scenarios for the origin and early evolution of life. These theories posit that RNA molecules played a much larger role in ancient biology than they do now, acting both as the dominant biocatalysts and as the repository of genetic information. Many features of modern RNA biology are potential examples of molecular fossils from an RNA world, such as the pervasive involvement of nucleotides in coenzymes, the existence of natural aptamers that bind these coenzymes, the existence of natural ribozymes, a biosynthetic pathway in which deoxynucleotides are produced from ribonucleotides, and the central role of ribosomal RNA in protein synthesis in the peptidyl transferase center of the ribosome. Here, we uses both a top-down approach that evaluates RNA function in modern biology and a bottom-up approach that examines the capacities of RNA independent of modern biology. These complementary approaches exploit multiple in vitro evolution techniques coupled with high-throughput sequencing and bioinformatics analysis. Together these complementary approaches advance our understanding of the most primitive organisms, their early evolution, and their eventual transition to modern biochemistry.

Oceanographic and climatic evolution of the southeastern subtropical Atlantic over the last 3.5 Ma

NASA Astrophysics Data System (ADS)

Petrick, Benjamin; McClymont, Erin L.; Littler, Kate; Rosell-Melé, Antoni; Clarkson, Matthew O.; Maslin, Mark; Röhl, Ursula; Shevenell, Amelia E.; Pancost, Richard D.

2018-06-01

The southeast Atlantic Ocean is dominated by two major oceanic systems: the Benguela Upwelling System, one of the world's most productive coastal upwelling cells and the Agulhas Leakage, which is important for transferring warm salty water from the Indian Ocean to the Atlantic Ocean. Here, we present a multi-proxy record of marine sediments from ODP Site 1087. We reconstruct sea surface temperatures (U37K‧ and TEX86 indices), marine primary productivity (total chlorin and alkenone mass accumulation rates), and terrestrial inputs derived from southern Africa (Ti/Al and Ca/Ti via XRF scanning) to understand the evolution of the Southeast Atlantic Ocean since the late Pliocene. In the late Pliocene and early Pleistocene, ODP Site 1087 was situated within the Benguela Upwelling System, which was displaced southwards relative to present. We recognize a series of events in the proxy records at 3.3, 3.0, 2.2, 1.5, 0.9 and 0.6 Ma, which are interpreted to reflect a combination of changes in the location of major global wind and oceanic systems and local variations in the strength and/or position of the winds, which influence nutrient availability. Although there is a temporary SST cooling observed around the initiation of Northern Hemisphere glaciation (iNHG), proxy records from ODP Site 1087 show no clear climatic transition around 2.7 Ma but instead most of the changes occur before this time. This observation is significant because it has been previously suggested that there should be a change in the location and/or strength of upwelling associated with this climate transition. Rather, the main shifts at ODP Site 1087 occur at ca. 0.9 Ma and 0.6 Ma, associated with the early mid-Pleistocene transition (EMPT), with a clear loss of the previous upwelling-dominated regime. This observation raises the possibility that reorganisation of southeast Atlantic Ocean circulation towards modern conditions was tightly linked to the EMPT, but not to earlier climate transitions.

NAS operational evolution plan : a foundation for capacity enhancement 2001-2010

DOT National Transportation Integrated Search

2001-06-01

This series of World Wide Web slides focuses on the Operational Evolution Plan, which is a 10-year plan for aviation operational improvements to increase capacity and safety in the United States. This plan is unique in that it integrates all actions:...

Evolution, Insight and Truth?

ERIC Educational Resources Information Center

Newall, Emma

2017-01-01

Evolution has been positioned at the centre of conflict between scientific and religious explanations of the workings of the world. However, little research has examined other possible reasons for some people rejecting scientific explanations. The author's research indicates that for some people, irrespective of faith, the ideas associated with…

Gay fathers: evolution of the gay-father identity.

PubMed

Bozett, Frederick W

1981-07-01

Interview data from an exploratory study of 18 gay fathers indicate that identity congruence evolves over time as these men participate in both the world of fathers and the world of gays. Disclosure of each identity in the opposite world, and the acceptance of both identities by intimate others, are also crucial to the gay father's achievement of self-acceptance.

Functional Morphology in Paleobiology: Origins of the Method of 'Paradigms'.

PubMed

Rudwick, Martin J S

2018-03-01

From the early nineteenth century, the successful use of fossils in stratigraphy oriented paleontology (and particularly the study of fossil invertebrates) towards geology. The consequent marginalising of biological objectives was countered in the twentieth century by the rise of 'Paläobiologie', first in the German cultural area and only later, as 'paleobiology', in the anglophone world. Several kinds of paleobiological research flourished internationally after the Second World War, among them the novel field of 'paleoecology'. Within this field there were attempts to apply functional morphology to the problematical cases of fossil organisms, for which functions cannot be observed directly. This article describes the origins of the kind of functional inference for fossils that I proposed in 1961 as the method of 'paradigms' (a year before Thomas Kuhn made that word more widely familiar with a quite different meaning). Here I summarize some of my 'worked exemplars', which were intended to show the paradigm method in action. These case-studies were all taken from the paleontologically important phylum of the Brachiopoda, but the method was claimed to have much wider implications for the interpretation of the fossil record in terms of adaptive evolution. This article takes the history of the paradigm method as far as the late 1960s. I hope to trace, in a sequel, its ambivalent fate during the 1970s and beyond, when for example Gould's critique of 'the adaptationist programme' and the rise of computer-based quantitative methods for the evolutionary interpretation of the fossil record led to the relative eclipse of functional morphology in paleontology.

Climate processes shape the evolution of populations and species leading to the assembly of modern biotas - examples along a continuum from shallow to deep time

NASA Astrophysics Data System (ADS)

Jacobs, D. K.

2014-12-01

California experiences droughts, so lets begin with the effects of streamflow variation on population evolution in a coastal lagoon-specialist endangered fish, the tidewater goby. Streamflow controls the closing and opening of lagoons to the sea determining genetic isolation or gene flow. Here evolution is a function of habitat preference for closing lagoons. Other estuarine fishes, with different habitat preferences, differentiate at larger spatial scales in response to longer glacio-eustatic control of estuarine habitat. Species of giraffes in Africa are a puzzle. Why do the ranges of large motile, potentially interbreeding, species occur in contact each other without hybridization? The answer resides in the timing of seasonal precipitation. Although the degree of seaonality of climate does not vary much between species, the timing of precipitation and seasonal "greenup" does. This provides a selective advantage to reproductive isolation, as reproductive timing can be coordinated in each region with seasonal browse availability for lactating females. Convective rainfall in Africa follows the sun and solar intensity is influenced by the precession cycle such that more extensive summer rains fell across the Sahara and South Asia early in the Holocene, this may also contribute to the genetic isolation and speciation of giraffes and others savanna species. But there also appears to be a correlation with rarity (CITES designation) of modern wetland birds, as the dramatic drying of the late Holocene landscape contributes to this conservation concern. Turning back to the West Coast we find the most diverse temperate coastal fauna in the world, yet this diversity evolved and is a relict of diversity accumulation during the apex of upwelling in the late Miocene, driven by the reglaciation of Antarctica. Lastly we can see that the deep-sea evolution is broadly constrained by the transitions from greenhouse to icehouse worlds over the last 90 mya as broad periods of warm climate coincide with episodic anoxia of the deep sea, influencing the evolutionary patterns seen in the fossil record and constraining the deep sea-vent faunas to be relatively young, having evolved/assembled from shallow water taxa late in the Cenozoic. Thus numerous discrete climate episodes yield the assembly of modern faunas.

Seizure semiology reflects spread from frontal to temporal lobe: evolution of hyperkinetic to automotor seizures as documented by invasive EEG video recordings.

PubMed

Tezer, Fadime Irsel; Agan, Kadriye; Borggraefe, Ingo; Noachtar, Soheyl

2013-09-01

This patient report demonstrates the importance of seizure evolution in the localising value of seizure semiology. Spread of epileptic activity from frontal to temporal lobe, as demonstrated by invasive recordings, was reflected by change from hyperkinetic movements to arrest of activity with mild oral and manual automatisms. [Published with video sequences].

Using Electronic Medical Records to Assess the Effectiveness of Pharmacotherapy in Pain: A Review of Recent Observational Studies.

PubMed

Biltaji, Eman; Tak, Casey; Ma, Junjie; Ruiz-Negron, Natalia; Bellows, Brandon K

2016-09-01

Pain disorders affect a large number of individuals throughout the world and are costly. Although randomized clinical trials assess the efficacy (i.e., how well treatments work in controlled settings) of pain pharmacotherapy, clinical trials do not assess effectiveness (i.e., how well treatments work in real-world settings). The number of observational studies that use real-world data to assess the effectiveness of medications is increasing rapidly in many disease areas. It is important for clinicians to understand how real-world data may be used to assess the effectiveness of medications. This paper aims to review the current body of literature assessing the effectiveness of pain pharmacotherapy using medical records. To do this, a literature search was conducted to identify papers published between January 2013 and September 2015 that examined the effectiveness of pain pharmacotherapy using electronic medical records. The search found only three papers meeting these criteria, which were described, reviewed, and critiqued in this paper. Electronic medical records are an underutilized source of data to assess pain outcomes in real-world settings. Although there are many methodological challenges in using these data, there is also great opportunity to impact clinical practice and explore the real-world effectiveness of pharmacotherapy used in pain management.

Shining evolutionary light on human sleep and sleep disorders.

PubMed

Nunn, Charles L; Samson, David R; Krystal, Andrew D

2016-01-01

Sleep is essential to cognitive function and health in humans, yet the ultimate reasons for sleep-i.e. 'why' sleep evolved-remain mysterious. We integrate findings from human sleep studies, the ethnographic record, and the ecology and evolution of mammalian sleep to better understand sleep along the human lineage and in the modern world. Compared to other primates, sleep in great apes has undergone substantial evolutionary change, with all great apes building a sleeping platform or 'nest'. Further evolutionary change characterizes human sleep, with humans having the shortest sleep duration, yet the highest proportion of rapid eye movement sleep among primates. These changes likely reflect that our ancestors experienced fitness benefits from being active for a greater portion of the 24-h cycle than other primates, potentially related to advantages arising from learning, socializing and defending against predators and hostile conspecifics. Perspectives from evolutionary medicine have implications for understanding sleep disorders; we consider these perspectives in the context of insomnia, narcolepsy, seasonal affective disorder, circadian rhythm disorders and sleep apnea. We also identify how human sleep today differs from sleep through most of human evolution, and the implications of these changes for global health and health disparities. More generally, our review highlights the importance of phylogenetic comparisons in understanding human health, including well-known links between sleep, cognitive performance and health in humans. © The Author(s) 2016. Published by Oxford University Press on behalf of the Foundation for Evolution, Medicine, and Public Health.

Adaptive evolution of the myo6 gene in old world fruit bats (family: pteropodidae).

PubMed

Shen, Bin; Han, Xiuqun; Jones, Gareth; Rossiter, Stephen J; Zhang, Shuyi

2013-01-01

Myosin VI (encoded by the Myo6 gene) is highly expressed in the inner and outer hair cells of the ear, retina, and polarized epithelial cells such as kidney proximal tubule cells and intestinal enterocytes. The Myo6 gene is thought to be involved in a wide range of physiological functions such as hearing, vision, and clathrin-mediated endocytosis. Bats (Chiroptera) represent one of the most fascinating mammal groups for molecular evolutionary studies of the Myo6 gene. A diversity of specialized adaptations occur among different bat lineages, such as echolocation and associated high-frequency hearing in laryngeal echolocating bats, large eyes and a strong dependence on vision in Old World fruit bats (Pteropodidae), and specialized high-carbohydrate but low-nitrogen diets in both Old World and New World fruit bats (Phyllostomidae). To investigate what role(s) the Myo6 gene might fulfill in bats, we sequenced the coding region of the Myo6 gene in 15 bat species and used molecular evolutionary analyses to detect evidence of positive selection in different bat lineages. We also conducted real-time PCR assays to explore the expression levels of Myo6 in a range of tissues from three representative bat species. Molecular evolutionary analyses revealed that the Myo6 gene, which was widely considered as a hearing gene, has undergone adaptive evolution in the Old World fruit bats which lack laryngeal echolocation and associated high-frequency hearing. Real-time PCR showed the highest expression level of the Myo6 gene in the kidney among ten tissues examined in three bat species, indicating an important role for this gene in kidney function. We suggest that Myo6 has undergone adaptive evolution in Old World fruit bats in relation to receptor-mediated endocytosis for the preservation of protein and essential nutrients.

Cellular Automata and the Humanities.

ERIC Educational Resources Information Center

Gallo, Ernest

1994-01-01

The use of cellular automata to analyze several pre-Socratic hypotheses about the evolution of the physical world is discussed. These hypotheses combine characteristics of both rigorous and metaphoric language. Since the computer demands explicit instructions for each step in the evolution of the automaton, such models can reveal conceptual…

The Evolution of DEOMI

DTIC Science & Technology

2017-09-15

technology opens the world to information in the computer database to all learners without the use of a human teacher other than the controller or manager ...THE EVOLUTION DE MI DEFENSE EQU AL OPPORTU NITY MANAG EMENT INST ITUTE IDENTITY TITLE: Dr. G · NAME: William Ga ry Mc u1re RACE: White NDER...The Evolution of DEOMI Defense Equal Opportunity Management Institute Research Directorate Written by William Gary McGuire, PhD

Trade-Off or Convergence? The Role of Food Security in the Evolution of Food Discourse in Italy

ERIC Educational Resources Information Center

Brunori, Gianluca; Malandrin, Vanessa; Rossi, Adanella

2013-01-01

In this paper we analyse the role that "food security" has played in the evolution of the food discourse in Italy, a country with a strong and internationally recognized food culture. We identify three phases of this evolution: in the first phase, from the end of the Second World War to the end of the 1980s, the "modernization"…

Differentiating the evolution of female song and male-female duets in the New World blackbirds: can tropical natural history traits explain duet evolution?

PubMed

Odom, Karan J; Omland, Kevin E; Price, J Jordan

2015-03-01

Female bird song and combined vocal duets of mated pairs are both frequently associated with tropical, monogamous, sedentary natural histories. Little is known, however, about what selects for duetting behavior versus female song. Female song likely preceded duet evolution and could drive apparent relationships between duets and these natural histories. We compared the evolution of female song and male-female duets in the New World blackbirds (Icteridae) by investigating patterns of gains and losses of both traits and their relationships with breeding latitude, mating system, nesting pattern, and migratory behavior. We found that duets evolved only in lineages in which female song was likely ancestral. Both female song and duets were correlated with tropical breeding, social monogamy, territorial nesting, and sedentary behavior when all taxa were included; however, correlations between duets and these natural history traits disappeared when comparisons were limited to taxa with female song. Also, likelihood values supported stronger relationships between the natural history traits and female song than between these traits and duets. Our results suggest that the natural histories thought to favor the evolution of duetting may in fact be associated with female song and that additional selection pressures are responsible for the evolution of duets. © 2015 The Author(s).

Evolution of Lower Brachyceran Flies (Diptera) and Their Adaptive Radiation with Angiosperms

PubMed Central

Zhang, Qingqing; Wang, Bo

2017-01-01

The Diptera (true flies) is one of the most species-abundant orders of Insecta, and it is also among the most important flower-visiting insects. Dipteran fossils are abundant in the Mesozoic, especially in the Late Jurassic and Early Cretaceous. Here, we review the fossil record and early evolution of some Mesozoic lower brachyceran flies together with new records in Burmese amber, including Tabanidae, Nemestrinidae, Bombyliidae, Eremochaetidae, and Zhangsolvidae. The fossil records reveal that some flower-visiting groups had diversified during the mid-Cretaceous, consistent with the rise of angiosperms to widespread floristic dominance. These brachyceran groups played an important role in the origin of co-evolutionary relationships with basal angiosperms. Moreover, the rise of angiosperms not only improved the diversity of flower-visiting flies, but also advanced the turnover and evolution of other specialized flies. PMID:28484485

Evolution of Lower Brachyceran Flies (Diptera) and Their Adaptive Radiation with Angiosperms.

PubMed

Zhang, Qingqing; Wang, Bo

2017-01-01

The Diptera (true flies) is one of the most species-abundant orders of Insecta, and it is also among the most important flower-visiting insects. Dipteran fossils are abundant in the Mesozoic, especially in the Late Jurassic and Early Cretaceous. Here, we review the fossil record and early evolution of some Mesozoic lower brachyceran flies together with new records in Burmese amber, including Tabanidae, Nemestrinidae, Bombyliidae, Eremochaetidae, and Zhangsolvidae. The fossil records reveal that some flower-visiting groups had diversified during the mid-Cretaceous, consistent with the rise of angiosperms to widespread floristic dominance. These brachyceran groups played an important role in the origin of co-evolutionary relationships with basal angiosperms. Moreover, the rise of angiosperms not only improved the diversity of flower-visiting flies, but also advanced the turnover and evolution of other specialized flies.

Nothing in the History of Spanish Anís Makes Sense, Except in the Light of Evolution

NASA Astrophysics Data System (ADS)

Delgado, Juan Antonio; Palma, Ricardo Luis

2011-02-01

We describe, discuss and illustrate a metaphoric parallel between the history of the most famous Spanish liqueur, " Anís del Mono" ( Anís of the Monkey), and the evolution of living organisms in the light of Darwinian theory and other biological hypotheses published subsequent to Charles Darwin's Origin of Species. Also, we report the use of a caricature of a simian Darwin with a positive connotation, perhaps the only one ever produced. We conclude that, like some species in the natural world, Anís of the Monkey has evolved, adapted, survived and become the fittest and most successful anís in the Spanish market and possibly the world. We hope this paper will contribute a new useful metaphor for the teaching of biological evolution.

Brain shape convergence in the adaptive radiation of New World monkeys

PubMed Central

Aristide, Leandro; dos Reis, Sergio Furtado; Machado, Alessandra C.; Lima, Inaya; Lopes, Ricardo T.; Perez, S. Ivan

2016-01-01

Primates constitute one of the most diverse mammalian clades, and a notable feature of their diversification is the evolution of brain morphology. However, the evolutionary processes and ecological factors behind these changes are largely unknown. In this work, we investigate brain shape diversification of New World monkeys during their adaptive radiation in relation to different ecological dimensions. Our results reveal that brain diversification in this clade can be explained by invoking a model of adaptive peak shifts to unique and shared optima, defined by a multidimensional ecological niche hypothesis. Particularly, we show that the evolution of convergent brain phenotypes may be related to ecological factors associated with group size (e.g., social complexity). Together, our results highlight the complexity of brain evolution and the ecological significance of brain shape changes during the evolutionary diversification of a primate clade. PMID:26858427

The Evolution of Consciousness in the Novel in English

NASA Astrophysics Data System (ADS)

Gojkovic, Zorica

This dissertation examines how the novel in English reflects the evolution of human consciousness. Characters in novels express a level of consciousness through their world view, which reflects the level of consciousness of the author and his/her period. Over time the world view evolves from a perception of physical reality as ultimate reality, to physical reality as illusion, in contrast to primary reality, which is spirit, or energy, or God, or the holistic frequency realm. Great mystics and sages all over the world, and throughout history, have had this understanding about the nature of reality. What is new is that different investigative currents are coming together and sharing this new vision of reality. The underlying unity, or enfolded order, is a broader realm where fragmentation is united by a deeper truth. This oneness is analogized to a hologram, where each part is in the whole and the whole in each part. The process of the evolution of consciousness in the novel is examined in three parts. In part one, Chapter One, connections are established between some of the pertinent developments in quantum physics, mysticism and Erich Neumann's theory of the evolution of consciousness. This information sets the stage for the exploration of the evolutionary process in the novel. Part two, chapters two to seven, explore various themes that demonstrate the evolutionary process in the novel. Novels that most effectively demonstrate the evolution are used. Part three, Chapter Eight, summarizes the evolutionary process and demonstrates the way in which wholeness is achieved from the initial separateness. Part three also explores some implications for the novel in light of this analysis.

Co-evolution of MHC class I and variable NK cell receptors in placental mammals.

PubMed

Guethlein, Lisbeth A; Norman, Paul J; Hilton, Hugo G; Parham, Peter

2015-09-01

Shaping natural killer (NK) cell functions in human immunity and reproduction are diverse killer cell immunoglobulin-like receptors (KIRs) that recognize polymorphic MHC class I determinants. A survey of placental mammals suggests that KIRs serve as variable NK cell receptors only in certain primates and artiodactyls. Divergence of the functional and variable KIRs in primates and artiodactyls predates placental reproduction. Among artiodactyls, cattle but not pigs have diverse KIRs. Catarrhine (humans, apes, and Old World monkeys) and platyrrhine (New World monkeys) primates, but not prosimians, have diverse KIRs. Platyrrhine and catarrhine systems of KIR and MHC class I are highly diverged, but within the catarrhines, a stepwise co-evolution of MHC class I and KIR is discerned. In Old World monkeys, diversification focuses on MHC-A and MHC-B and their cognate lineage II KIR. With evolution of C1-bearing MHC-C from MHC-B, as informed by orangutan, the focus changes to MHC-C and its cognate lineage III KIR. Evolution of C2 from C1 and fixation of MHC-C drove further elaboration of MHC-C-specific KIR, as exemplified by chimpanzee. In humans, the evolutionary trajectory changes again. Emerging from reorganization of the KIR locus and selective attenuation of KIR avidity for MHC class I are the functionally distinctive KIR A and KIR B haplotypes. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Greenstone belts: Their boundaries, surrounding rock terrains and interrelationships

NASA Technical Reports Server (NTRS)

Percival, J. A.; Card, K. D.

1986-01-01

Greenstone belts are an important part of the fragmented record of crustal evolution, representing samples of the magmatic activity that formed much of the Earth's crust. Most belts developed rapidly, in less than 100 Ma, leaving large gaps in the geological record. Surrounding terrains provide information on the context of greenstone belts. The effects of tectonic setting, structural geometry and evolution, associated plutonic activity and sedimentation are discussed.

[The written nursing reports of the asylum "Paolo Pini" of Milan, from 1944 to 1947].

PubMed

Negri, Marina; Marchesini, Vanna; De Valerio, Silvio; Soro, Emiliana

2017-01-01

The work provides the analysis of the nursing reports written by the nursing staff on duty at the asylum "Paolo Pini" from 1944 to 1947. description of the nursing report evolution, analyses of the quantitative and qualitative matters. Study of the evolution of the records: enhancement of the description of the patient, integration between medical and nursing assistance, assumption of responsi- bility (for instance through the signature). A sampling of 355 medical records has been analysed. The nursing records have been identified according to the theoretical model of Marisa Cantarelli. They have been compared with the current standard reported in literature. If recognizable signatures were present, they have been checked in the archives of the Province of Milan. 219 records concerning nursing assistance have been selected. The record changed during the years assuming a definite structure, and became a pre printed form; its use spread in all the wards of the hospital. The record deals with nursing assistance needs, and improves during the years becoming more and more detailed and regular. During the analysed time frame, the nursing reports at "Paolo Pini" improve and become more exhaustive and regular; they prove to be part of the medical record, showing a good integration between doctors and nurses activities. The evolution of this tool confirms the need of highlighting and improving the assistance practice.

NASA's Advanced Multimission Operations System: A Case Study in Formalizing Software Architecture Evolution

NASA Technical Reports Server (NTRS)

Barnes, Jeffrey M.

2011-01-01

All software systems of significant size and longevity eventually undergo changes to their basic architectural structure. Such changes may be prompted by evolving requirements, changing technology, or other reasons. Whatever the cause, software architecture evolution is commonplace in real world software projects. Recently, software architecture researchers have begun to study this phenomenon in depth. However, this work has suffered from problems of validation; research in this area has tended to make heavy use of toy examples and hypothetical scenarios and has not been well supported by real world examples. To help address this problem, I describe an ongoing effort at the Jet Propulsion Laboratory to re-architect the Advanced Multimission Operations System (AMMOS), which is used to operate NASA's deep-space and astrophysics missions. Based on examination of project documents and interviews with project personnel, I describe the goals and approach of this evolution effort and then present models that capture some of the key architectural changes. Finally, I demonstrate how approaches and formal methods from my previous research in architecture evolution may be applied to this evolution, while using languages and tools already in place at the Jet Propulsion Laboratory.

Knowledge Evolution in Distributed Geoscience Datasets and the Role of Semantic Technologies

NASA Astrophysics Data System (ADS)

Ma, X.

2014-12-01

Knowledge evolves in geoscience, and the evolution is reflected in datasets. In a context with distributed data sources, the evolution of knowledge may cause considerable challenges to data management and re-use. For example, a short news published in 2009 (Mascarelli, 2009) revealed the geoscience community's concern that the International Commission on Stratigraphy's change to the definition of Quaternary may bring heavy reworking of geologic maps. Now we are in the era of the World Wide Web, and geoscience knowledge is increasingly modeled and encoded in the form of ontologies and vocabularies by using semantic technologies. Accordingly, knowledge evolution leads to a consequence called ontology dynamics. Flouris et al. (2008) summarized 10 topics of general ontology changes/dynamics such as: ontology mapping, morphism, evolution, debugging and versioning, etc. Ontology dynamics makes impacts at several stages of a data life cycle and causes challenges, such as: the request for reworking of the extant data in a data center, semantic mismatch among data sources, differentiated understanding of a same piece of dataset between data providers and data users, as well as error propagation in cross-discipline data discovery and re-use (Ma et al., 2014). This presentation will analyze the best practices in the geoscience community so far and summarize a few recommendations to reduce the negative impacts of ontology dynamics in a data life cycle, including: communities of practice and collaboration on ontology and vocabulary building, link data records to standardized terms, and methods for (semi-)automatic reworking of datasets using semantic technologies. References: Flouris, G., Manakanatas, D., Kondylakis, H., Plexousakis, D., Antoniou, G., 2008. Ontology change: classification and survey. The Knowledge Engineering Review 23 (2), 117-152. Ma, X., Fox, P., Rozell, E., West, P., Zednik, S., 2014. Ontology dynamics in a data life cycle: Challenges and recommendations from a Geoscience Perspective. Journal of Earth Science 25 (2), 407-412. Mascarelli, A.L., 2009. Quaternary geologists win timescale vote. Nature 459, 624.

Evolution and Education: Lessons from Thomas Huxley

ERIC Educational Resources Information Center

Lyons, Sherrie Lynne

2010-01-01

Thomas Huxley more than anyone else was responsible for disseminating Darwin's theory in the western world and maintained that investigating the history of life should be regarded as a purely scientific question free of theological speculation. The content and rhetorical strategy of Huxley's defense of evolution is analyzed. Huxley argued that the…

Evolution: Don't Debate, Educate.

ERIC Educational Resources Information Center

Bybee, Rodger W.

2000-01-01

Discusses controversy over the teaching of biological evolution and other scientific ideas such as Big Bang theory. Recommends that teachers avoid debating creationists, help students develop a greater understanding and appreciation for science as a way of explaining the natural world, and emphasize inquiry and the nature of science. (Contains 19…

The Theory of Evolution: An Educational Perspective.

ERIC Educational Resources Information Center

Johnson, William L.; Johnson, Annabel M.

The article's thesis is that evolution's intellectual foundations have been steadily eroding, and that few new findings in embryology, taxonomy, fossil remains, and molecular biology are bringing us very near to a formal, logical disproof of Darwinian claims. The paper begins by discussing the evidence of a prehistoric world, then they discuss…

Evolution and the End of a World

ERIC Educational Resources Information Center

Long, David Edward

2010-01-01

This dissertation examines college student understanding and attitudes toward biological evolution. In ethnographic work, I followed a cohort of 31 students through their required introductory biology class. In interviews, students discuss their life history with the concept--in school, at home, at church, and in their communities. For some…

The Convergent Evolution of a Chemistry Project: Using Laboratory Posters as a Platform for Web Page Construction.

ERIC Educational Resources Information Center

Rigeman, Sally

1998-01-01

Argues that evolution is a process that occurs within the curriculum as well as within the physical universe. Provides an example that involves student presentations. Discusses the transition from poster presentations to electronic presentations via the World Wide Web. (DDR)

Open database of epileptic EEG with MRI and postoperational assessment of foci--a real world verification for the EEG inverse solutions.

PubMed

Zwoliński, Piotr; Roszkowski, Marcin; Zygierewicz, Jaroslaw; Haufe, Stefan; Nolte, Guido; Durka, Piotr J

2010-12-01

This paper introduces a freely accessible database http://eeg.pl/epi , containing 23 datasets from patients diagnosed with and operated on for drug-resistant epilepsy. This was collected as part of the clinical routine at the Warsaw Memorial Child Hospital. Each record contains (1) pre-surgical electroencephalography (EEG) recording (10-20 system) with inter-ictal discharges marked separately by an expert, (2) a full set of magnetic resonance imaging (MRI) scans for calculations of the realistic forward models, (3) structural placement of the epileptogenic zone, recognized by electrocorticography (ECoG) and post-surgical results, plotted on pre-surgical MRI scans in transverse, sagittal and coronal projections, (4) brief clinical description of each case. The main goal of this project is evaluation of possible improvements of localization of epileptic foci from the surface EEG recordings. These datasets offer a unique possibility for evaluating different EEG inverse solutions. We present preliminary results from a subset of these cases, including comparison of different schemes for the EEG inverse solution and preprocessing. We report also a finding which relates to the selective parametrization of single waveforms by multivariate matching pursuit, which is used in the preprocessing for the inverse solutions. It seems to offer a possibility of tracing the spatial evolution of seizures in time.

A Possible Connection between the 1878 Yellow Fever Epidemic in the Southern United States and the 1877-78 El Niño Episode.

NASA Astrophysics Data System (ADS)

Diaz, Henry F.; McCabe, Gregory J.

1999-01-01

One of the most severe outbreaks of yellow fever, a viral disease transmitted by the Aedes aegypti mosquito, affected the southern United States in the summer of 1878. The economic and human toll was enormous, and the city of Memphis, Tennessee, was one of the most affected. The authors suggest that as a consequence of one of the strongest El Niño episodes on record-that which occurred in 1877-78-exceptional climate anomalies occurred in the United States (as well as in many other parts of the world), which may have been partly responsible for the widespread nature and severity of the 1878 yellow fever outbreak.This study documents some of the extreme climate anomalies that were recorded in 1877 and 1878 in parts of the eastern United States, with particular emphasis on highlighting the evolution of these anomalies, as they might have contributed to the epidemic. Other years with major outbreaks of yellow fever in the eighteenth and nineteenth centuries also occurred during the course of El Niño episodes, a fact that appears not to have been noted before in the literature.

Astrobiology and the Biological Universe

NASA Astrophysics Data System (ADS)

Dick, S. J.

2002-12-01

Four hundred years ago two astronomical world views hung in the balance: the geocentric and the heliocentric. Today astronomy faces a similar choice between two grand world views: a purely physical universe, in which cosmic evolution commonly ends in planets, stars and galaxies, and a biological universe, in which cosmic evolution routinely results in life, mind and intelligence. Astrobiology is the science providing the data to make this critical choice. This 20th century overview shows how we have arrived at the view that cosmic evolution may have resulted in life and intelligence in the universe. It examines how our astronomical world view has changed over the last century, recalls the opinions of astronomical pioneers like Russell, Shapley, and Struve on life in the universe, and shows how planetary science, planetary systems science, origins of life studies and SETI have combined to form a new discipline. Astrobiology now commands \\$50 million in direct funding from NASA, funds 15 Astrobiology Institute members around the country and four affiliates around the world, and seeks to answer one of astronomy's oldest questions. Whether we live in a mostly physical universe, as exemplified in Isaac Asimov's Foundation series, or in a biological universe, as portrayed in Arthur C. Clarke's works, this reality will have profound consequences, no less than the Copernican theory. Astrobiology also looks to the future of life; taking a long-term ``Stapledonian" view, it is possible we may live in a postbiological universe.

Integrating Real World Entities into an Academic Curriculum

ERIC Educational Resources Information Center

Tompkins, Terrance; Schlesinger, Marc

2010-01-01

This research will demonstrate how an experiential learning practicum can be successfully implemented into an academic curriculum, using Drexel University's (Philadelphia, PA) award-winning student-run record label, MAD Dragon Records, as a case study. It will describe the components necessary to implement and operate a real-world entity within…

Frequency-Domain Tomography for Single-shot, Ultrafast Imaging of Evolving Laser-Plasma Accelerators

NASA Astrophysics Data System (ADS)

Li, Zhengyan; Zgadzaj, Rafal; Wang, Xiaoming; Downer, Michael

2011-10-01

Intense laser pulses propagating through plasma create plasma wakefields that often evolve significantly, e.g. by expanding and contracting. However, such dynamics are known in detail only through intensive simulations. Laboratory visualization of evolving plasma wakes in the ``bubble'' regime is important for optimizing and scaling laser-plasma accelerators. Recently snap-shots of quasi-static wakes were recorded using frequency-domain holography (FDH). To visualize the wake's evolution, we have generalized FDH to frequency-domain tomography (FDT), which uses multiple probes propagating at different angles with respect to the pump pulse. Each probe records a phase streak, imprinting a partial record of the evolution of pump-created structures. We then topographically reconstruct the full evolution from all phase streaks. To prove the concept, a prototype experiment visualizing nonlinear index evolution in glass is demonstrated. Four probes propagating at 0, 0.6, 2, 14 degrees to the index ``bubble'' are angularly and temporally multiplexed to a single spectrometer to achieve cost-effective FDT. From these four phase streaks, an FDT algorithm analogous to conventional CT yields a single-shot movie of the pump's self-focusing dynamics.

Review of "World Bank Financing of Education: Lending, Learning, and Development," by Phillip W. Jones.

ERIC Educational Resources Information Center

Spaulding, Seth

1996-01-01

Reviews current criticisms of World Bank educational projects and their negative impacts on developing nations as context for a book that traces the evolution of Bank policies from its first projects in the 1960s to the present. (SV)

Evolution in a fully constituted world: Charles Darwin's debts towards a static world in the Origin of Species (1859).

PubMed

Delisle, Richard G

2014-01-01

The Transformist Revolution was a long intellectual quest that has expanded from the 18th century to today. One area of inquiry after another has confronted the necessity of recasting its object of study under an evolutionary view: human history, geology, biology, astronomy, etc. No single scholar fully managed to make the transition from a static worldview to an evolutionary one during his or her own lifetime; Charles Darwin is no exception. Many versions of evolutionism were proposed during this revolution, versions offering all sorts of compromises between old and new views. Not sufficiently acknowledged in the historiography is the profoundness of Darwin's debts towards the old static view. As a dual child of the Scientific Revolution and natural theology, Darwin inherited key concepts such as stability, completeness, timelessness, unity, permanence, and uniformity. Darwin took these concepts into consideration while erecting his theory of biological evolution. Unsurprisingly, this theory was ill-equipped to embrace the directionality, historicity, and novelty that came along with a new evolutionary world. This paper analyses a fundamental idea at the heart of Darwin's Origins of Species (1859) inherited from a static, stable, and machine-like conception of the world: the notion of a fully constituted world. Although in principle antithetical to the very idea of evolution itself, Darwin found a way to 'loosen up' this notion so as to retain it in a way that allows for some kind of evolutionary change. Copyright © 2014 Elsevier Ltd. All rights reserved.

Spiders in caves.

PubMed

Mammola, Stefano; Isaia, Marco

2017-04-26

World experts of different disciplines, from molecular biology to macro-ecology, recognize the value of cave ecosystems as ideal ecological and evolutionary laboratories. Among other subterranean taxa, spiders stand out as intriguing model organisms for their ecological role of top predators, their unique adaptations to the hypogean medium and their sensitivity to anthropogenic disturbance. As the description of the first eyeless spider ( Stalita taenaria ), an array of papers on subterranean spider biology, ecology and evolution has been published, but a comprehensive review on these topics is still lacking. We provide a general overview of the spider families recorded in hypogean habitats worldwide, we review the different adaptations of hypogean spiders to subterranean life, and we summarize the information gathered so far about their origin, population structure, ecology and conservation status. Finally, we point out the limits of the knowledge we currently have regarding hypogean spiders, aiming to stimulate future research. © 2017 The Author(s).

Spiders in caves

PubMed Central

2017-01-01

World experts of different disciplines, from molecular biology to macro-ecology, recognize the value of cave ecosystems as ideal ecological and evolutionary laboratories. Among other subterranean taxa, spiders stand out as intriguing model organisms for their ecological role of top predators, their unique adaptations to the hypogean medium and their sensitivity to anthropogenic disturbance. As the description of the first eyeless spider (Stalita taenaria), an array of papers on subterranean spider biology, ecology and evolution has been published, but a comprehensive review on these topics is still lacking. We provide a general overview of the spider families recorded in hypogean habitats worldwide, we review the different adaptations of hypogean spiders to subterranean life, and we summarize the information gathered so far about their origin, population structure, ecology and conservation status. Finally, we point out the limits of the knowledge we currently have regarding hypogean spiders, aiming to stimulate future research. PMID:28446696

Distribution of subtidal sedimentary bedforms in a macrotidal setting: The Bay of Fundy, Atlantic Canada

NASA Astrophysics Data System (ADS)

Todd, Brian J.; Shaw, John; Li, Michael Z.; Kostylev, Vladimir E.; Wu, Yongsheng

2014-07-01

The Bay of Fundy, Canada, a large macrotidal embayment with the World's highest recorded tides, was mapped using multibeam sonar systems. High-resolution imagery of seafloor terrain and backscatter strength, combined with geophysical and sampling data, reveal for the first time the morphology, architecture, and spatial relationships of a spectrum of bedforms: (1) flow-transverse bedforms occur as both discrete large two-dimensional dunes and as three-dimensional dunes in sand sheets; (2) flow-parallel bedforms are numerous straight ridges described by others as horse mussel bioherms; (3) sets of banner banks that flank prominent headlands and major shoals. The suite of bedforms developed during the Holocene, as tidal energy increased due to the bay approaching resonance. We consider the evolution of these bedforms, their migration potential and how they may place limitations on future in-stream tidal power development in the Bay of Fundy.

Aqueous geochemistry in icy world interiors: Equilibrium fluid, rock, and gas compositions, and fate of antifreezes and radionuclides

NASA Astrophysics Data System (ADS)

Neveu, Marc; Desch, Steven J.; Castillo-Rogez, Julie C.

2017-09-01

The geophysical evolution of many icy moons and dwarf planets seems to have provided opportunities for interaction between liquid water and rock (silicate and organic solids). Here, we explore two ways by which water-rock interaction can feed back on geophysical evolution: the production or consumption of antifreeze compounds, which affect the persistence and abundance of cold liquid; and the potential leaching into the fluid of lithophile radionuclides, affecting the distribution of a long-term heat source. We compile, validate, and use a numerical model, implemented with the PHREEQC code, of the interaction of chondritic rock with pure water and with C, N, S-bearing cometary fluid, thought to be the materials initially accreted by icy worlds, and describe the resulting equilibrium fluid and rock assemblages at temperatures, pressures, and water-to-rock ratios of 0-200 ° C, 1-1000 bar, and 0.1-10 by mass, respectively. Our findings suggest that water-rock interaction can strongly alter the nature and amount of antifreezes, resulting in solutions rich in reduced nitrogen and carbon, and sometimes dissolved H2, with additional sodium, calcium, chlorine, and/or oxidized carbon. Such fluids can remain partially liquid down to 176 K if NH3 is present. The prominence of Cl in solution seems to hinge on its primordial supply in ices, which is unconstrained by the meteoritical record. Equilibrium assemblages, rich in serpentine and saponite clays, retain thorium and uranium radionuclides unless U-Cl or U-HCO3 complexing, which was not modeled, significantly enhances U solubility. However, the radionuclide 40 K can be leached at high water:rock ratio and/or low temperature at which K is exchanged with ammonium in minerals. We recommend the inclusion of these effects in future models of the geophysical evolution of ocean-bearing icy worlds. Our simulation products match observations of chloride salts on Europa and Enceladus; CI chondrites mineralogies; the observation of serpentines, NH4-phyllosilicates, and carbonates on Ceres' surface; and of Na and NH4-carbonate and chloride in Ceres' bright spots. They also match results from previous modeling studies with similar assumptions, and systematically expand these results to heretofore unexplored physico-chemical conditions. This work involved the compilation and careful validation of a comprehensive PHREEQC database, which combines the advantages of the default databases phreeqc.dat (carefully vetted data, molar volumes) and llnl.dat (large diversity of species), and should be of broad use to anyone seeking to model aqueous geochemistry at pressures that differ from 1 bar with PHREEQC.

The Menengai Tuff: A 36 ka widespread tephra and its chronological relevance to Late Pleistocene human evolution in East Africa

NASA Astrophysics Data System (ADS)

Blegen, Nick; Brown, Francis H.; Jicha, Brian R.; Binetti, Katie M.; Faith, J. Tyler; Ferraro, Joseph V.; Gathogo, Patrick N.; Richardson, Jonathan L.; Tryon, Christian A.

2016-11-01

The East African Rift preserves the world's richest Middle and Late Pleistocene (∼780-12 ka) geological, archaeological and paleontological archives relevant to the emergence of Homo sapiens. This region also provides unparalleled chronological control for many important sites through tephrochronology, the dating and correlation of volcanic ashes as widespread isochronous markers in the geological record. There are many well-characterized Pliocene-Early Pleistocene tephras that are widespread across East Africa. A comparable framework is lacking for the Middle and Late Pleistocene; a period characterized by spatially and temporally complex patterns of climate change, as well as the emergence of modern Homo sapiens and the dispersal of this species across and out of Africa. Unraveling relationships among these spatial and temporally complex phenomena requires a precise chronology. To this end we report the Menengai Tuff, a widespread volcanic ash produced by the large-scale caldera-forming eruption in Kenya and 40Ar/39Ar dated to 35.62 ± 0.26 ka. Geochemical characterization of 565 glass shards from 36 samples by wavelength-dispersive electron probe microanalysis show the Menengai Tuff was deposited over >115,000 km2 and is found in the Baringo, Chalbi, Elmenteita, Nakuru, Olorgesailie, Turkana, and Victoria basins, all of which preserve rich Late Pleistocene paleoenvironmental and archaeological archives. Correlation and dating of the Menengai Tuff demonstrate that it is the most widespread tephra and largest eruption currently known from the Late Pleistocene of East Africa. As such, it is a valuable marker in establishing a Late Pleistocene chronology for paleoclimatic, archeological, and paleontological records relevant to the study of human evolution.

Mega-Impacts on Mars: Implications for the Late Heavy Bombardment in the Inner Solar System, and the Early Evolution of the Earth and Mars

NASA Technical Reports Server (NTRS)

Frey, Herbert

2012-01-01

There are about 30 very large impact basins on Mars, > 1000 km in diameter, most of which are revealed by their topographic and/or crustal thickness signatures. Crater retention ages and model absolute ages suggest these all formed in a relatively short time (100-200 million years?), perhaps during a "Late Heavy Bombardment" (LHB) caused by the evolution of the orbits of the giant planets. This so-called "Nice Model" of planetary formation may explain the LHB on the Moon at about 3.9 billion years ago and would have produced a similar bombardment throughout the inner solar system. The formation of 30 very large impact basins would have had catastrophic environmental consequences for Mars, which were further complicated by the demise of the global magnetic field at about the same time. If there are no very large basins on Mars older than the 30 we see and the LHB really lasted everywhere only a short time, there may have been a relatively longer time (400 million years?) during which Mars and the Earth suffered no major impact trauma and during which conditions on both worlds may have been far more habitable than during the LHB. However, if the formation of the Mars crustal dichotomy was due to an even larger giant impact that predated the very large basins, all record of this earlier and possibly more clement time on Mars may have been erased. Ages of the smaller but still very large basins can be used to approximately date the giant impact (if it occurred). Even the very large basins appear to have reset the crater retention ages of the entire crust of Mars and may have by themselves erased any record of an earlier time.

Real-world research and the role of observational data in the field of gynaecology - a practical review.

PubMed

Heikinheimo, Oskari; Bitzer, Johannes; García Rodríguez, Luis

2017-08-01

In the context of women's health, we examine (1) the role that observational ('real-world') studies have in overcoming limitations of randomised clinical trials, (2) the relative advantages and disadvantages of different study designs, (3) the importance of outcome data from observational studies when making health-economic or clinical decisions, and (4) provide insights into changing perceptions of observational clinical data. PubMed and internet searches were used to identify (i) guidance and expert commentary on designing, conducting, analysing, and reporting clinical trials or observational studies, (ii) supporting evidence of the rapid growth of observational ('real world') studies and publications since the turn of millennium in the fields of contraception, reproductive health, obstetrics or gynaecology. The rapidly growing use and validation of large, computerised medical records and related databases (e.g., health insurance or national registries) have played a major part in changing perceptions of observational data among researchers and clinicians. In the past 10 years, a distinct increase in the number of observational studies published tends to confirm their growing acceptance, appreciation and use. Observational studies can provide information that is impossible or infeasible to obtain otherwise (e.g., impractical, very expensive, or ethically unacceptable). Greater understanding, dissemination, uptake and use of observational data might be expected to drive ongoing evolution of research, data collection, analysis, and validation, in turn improving quality and therefore credibility, utility, and further application by clinicians.

The Role and Tasks of Education in the Politic of Evolution of the Modern World (with Especial Regard to the Developing Countries).

ERIC Educational Resources Information Center

Podoski, Kazimierz

This paper, one of several on the theme of economy and culture in the politics of nation building, was written for the Ninth World Congress of the International Political Science Association. The author's aim is to indicate the role of modern education policy in the world's socio-economic development, especially in developing countries. Access to…

Analysis of World Economic Variables Using Multidimensional Scaling

PubMed Central

Machado, J.A. Tenreiro; Mata, Maria Eugénia

2015-01-01

Waves of globalization reflect the historical technical progress and modern economic growth. The dynamics of this process are here approached using the multidimensional scaling (MDS) methodology to analyze the evolution of GDP per capita, international trade openness, life expectancy, and education tertiary enrollment in 14 countries. MDS provides the appropriate theoretical concepts and the exact mathematical tools to describe the joint evolution of these indicators of economic growth, globalization, welfare and human development of the world economy from 1977 up to 2012. The polarization dance of countries enlightens the convergence paths, potential warfare and present-day rivalries in the global geopolitical scene. PMID:25811177

Nonecholocating fruit bats produce biosonar clicks with their wings.

PubMed

Boonman, Arjan; Bumrungsri, Sara; Yovel, Yossi

2014-12-15

Because evolution mostly acts over millions of years, the intermediate steps leading to a functional sensory system remain enigmatic. Accordingly, there is an ongoing debate regarding the evolution of bat echolocation. In search of the origin of bat echolocation, we studied how Old World fruit bats, which have always been classified as nonecholocating, orient in complete darkness. We found that two of these nonecholocating species used click-like sounds to detect and discriminate objects in complete darkness. However, we discovered that this click-based echo sensing is rudimentary and does not allow these bats to estimate distance accurately as all other echolocating bats can. Moreover, unlike all other echolocating bats, which generate pulses using the larynx or the tongue, these bats generated clicks with their wings. We provide evidence suggesting that all Old World fruit bats can click with their wings. Although this click-based echo sensing used by Old World fruit bats may not represent the ancestral form of current (laryngeal) bat echolocation, we argue that clicking fruit bats could be considered behavioral fossils, opening a window to study the evolution of echolocation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Three Essays on Digital Evolution

ERIC Educational Resources Information Center

Zhang, Zhewei

2016-01-01

Digital products are rapidly shaping our world into a ubiquitous computing world. Because of its unique characteristics, digital artifacts are generative and highly evolving through the recombination of existing elements as well as by the invention of new elements. In this thesis, I first propose an evolutionary view to examine how digital…

Consciously Thinking about Consciousness

ERIC Educational Resources Information Center

Tribus, Myron

2004-01-01

Merker hypothesized that because mobile creatures move around and must constantly readjust their map of the world and because the demands are so great for continually processing information for a map of the world, evolution has created a space in the brain where such preprocessing has been eliminated. This space he calls consciousness with the…

Cesar Chavez--Grade Ten Model Curriculum and Resources.

ERIC Educational Resources Information Center

California State Dept. of Education, Sacramento.

In this California state curriculum model for grade 10, "World History, Culture, and Geography: The Modern World," students stud the life, work, and philosophy of Cesar E. Chavez. The students learn about the historical developments of many of the ideas and philosophy of Chavez, particularly the evolution of democratic principles.…

Beyond ICARA II: Implementing Refugee-Related Development Assistance.

ERIC Educational Resources Information Center

Gorman, Robert F.

1986-01-01

Reviews the evolution of the Second International Conference on Assistance to Refugees in Africa, which advanced discussions on the connection between refugees and the development process. Discusses potential roles of the World Bank and the World Food Program in providing technical assistance to refugee-related development projects. (Author/GC)

Nonlinear viscosity in brane-world cosmology with a Gauss–Bonnet term

NASA Astrophysics Data System (ADS)

Debnath, P. S.; Beesham, A.; Paul, B. C.

2018-06-01

Cosmological solutions are obtained with nonlinear bulk viscous cosmological fluid in the Randall–Sundrum type II (RS) brane-world model with or without Gauss–Bonnet (GB) terms. To describe such a viscous fluid, we consider the nonlinear transport equation which may be used far from equilibrium during inflation or reheating. Cosmological models are explored for both (i) power law and (ii) exponential evolution of the early universe in the presence of an imperfect fluid described by the non-linear Israel and Stewart theory (nIS). We obtain analytic solutions and the complex field equations are also analyzed numerically to study the evolution of the universe. The stability analysis of the equilibrium points of the dynamical system associated with the evolution of the nonlinear bulk viscous fluid in the RS Brane in the presence (or absence) of a GB term are also studied.

Why sauropods had long necks; and why giraffes have short necks.

PubMed

Taylor, Michael P; Wedel, Mathew J

2013-01-01

The necks of the sauropod dinosaurs reached 15 m in length: six times longer than that of the world record giraffe and five times longer than those of all other terrestrial animals. Several anatomical features enabled this extreme elongation, including: absolutely large body size and quadrupedal stance providing a stable platform for a long neck; a small, light head that did not orally process food; cervical vertebrae that were both numerous and individually elongate; an efficient air-sac-based respiratory system; and distinctive cervical architecture. Relevant features of sauropod cervical vertebrae include: pneumatic chambers that enabled the bone to be positioned in a mechanically efficient way within the envelope; and muscular attachments of varying importance to the neural spines, epipophyses and cervical ribs. Other long-necked tetrapods lacked important features of sauropods, preventing the evolution of longer necks: for example, giraffes have relatively small torsos and large, heavy heads, share the usual mammalian constraint of only seven cervical vertebrae, and lack an air-sac system and pneumatic bones. Among non-sauropods, their saurischian relatives the theropod dinosaurs seem to have been best placed to evolve long necks, and indeed their necks probably surpassed those of giraffes. But 150 million years of evolution did not suffice for them to exceed a relatively modest 2.5 m.

Why sauropods had long necks; and why giraffes have short necks

PubMed Central

Wedel, Mathew J.

2013-01-01

The necks of the sauropod dinosaurs reached 15 m in length: six times longer than that of the world record giraffe and five times longer than those of all other terrestrial animals. Several anatomical features enabled this extreme elongation, including: absolutely large body size and quadrupedal stance providing a stable platform for a long neck; a small, light head that did not orally process food; cervical vertebrae that were both numerous and individually elongate; an efficient air-sac-based respiratory system; and distinctive cervical architecture. Relevant features of sauropod cervical vertebrae include: pneumatic chambers that enabled the bone to be positioned in a mechanically efficient way within the envelope; and muscular attachments of varying importance to the neural spines, epipophyses and cervical ribs. Other long-necked tetrapods lacked important features of sauropods, preventing the evolution of longer necks: for example, giraffes have relatively small torsos and large, heavy heads, share the usual mammalian constraint of only seven cervical vertebrae, and lack an air-sac system and pneumatic bones. Among non-sauropods, their saurischian relatives the theropod dinosaurs seem to have been best placed to evolve long necks, and indeed their necks probably surpassed those of giraffes. But 150 million years of evolution did not suffice for them to exceed a relatively modest 2.5 m. PMID:23638372

Universality, Limits and Predictability of Gold-Medal Performances at the Olympic Games

PubMed Central

Radicchi, Filippo

2012-01-01

Inspired by the Games held in ancient Greece, modern Olympics represent the world’s largest pageant of athletic skill and competitive spirit. Performances of athletes at the Olympic Games mirror, since 1896, human potentialities in sports, and thus provide an optimal source of information for studying the evolution of sport achievements and predicting the limits that athletes can reach. Unfortunately, the models introduced so far for the description of athlete performances at the Olympics are either sophisticated or unrealistic, and more importantly, do not provide a unified theory for sport performances. Here, we address this issue by showing that relative performance improvements of medal winners at the Olympics are normally distributed, implying that the evolution of performance values can be described in good approximation as an exponential approach to an a priori unknown limiting performance value. This law holds for all specialties in athletics–including running, jumping, and throwing–and swimming. We present a self-consistent method, based on normality hypothesis testing, able to predict limiting performance values in all specialties. We further quantify the most likely years in which athletes will breach challenging performance walls in running, jumping, throwing, and swimming events, as well as the probability that new world records will be established at the next edition of the Olympic Games. PMID:22808137

Past, present, and future of sublimation transfer imaging

NASA Astrophysics Data System (ADS)

Akada, Masanori

1990-07-01

SONY's announcement of tlavica system shaked the world in 1981. In the new nonphotographic imaging system, image is acquired with CCD to be converted into electric image-signal, stored in magnetic recording media,displayed on a CR1 and printed on a special sheet. To get a hard copy, Sublimation Transfer technology was developed. That announcement brought about world-wide R&D of competitive color imaging systems: Ink-jet, Wax transfer,. Sublimation Transfer(ST) and Electrophotography. In spite of much effort,most of those were insufficient for getting a good hard copy. Developing sufficient ST recording media, Dai Nippon Printing started ST recording media business in 1986. It was the first manufacturing scale production and sale of ST recording media in the world. Nowadays ST technology is known for its advantages: high image quality, consistency from copy to copy, smooth tone-reproduction from high-light to maximum density, and easiness to use. In the following paper progress of ST recording media and the present situation and future markets of the media will be presented.

Climatic Change and Human Evolution.

ERIC Educational Resources Information Center

Garratt, John R.

1995-01-01

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

Evolutionary Creation: Moving beyond the Evolution versus Creation Debate

ERIC Educational Resources Information Center

Lamoureux, Denis O.

2010-01-01

Evolutionary creation offers a conservative Christian approach to evolution. It explores biblical faith and evolutionary science through a Two Divine Books model and proposes a complementary relationship between Scripture and science. The Book of God's Words discloses the spiritual character of the world, while the Book of God's Works reveals the…

"Why Are There Still Apes if Apes Have Changed into People?"

ERIC Educational Resources Information Center

Russell, Terry; McGuigan, Linda

2015-01-01

"Evolution" is an area of the curriculum in which children show great interest and enthusiasm to learn more. They also bring considerable prior (though incomplete) knowledge from their informal "life worlds". Most children have encountered the term "evolution" from an early age and tend to define it in terms of…

Evolution of Singapore's School Mathematics Curriculum

ERIC Educational Resources Information Center

Kaur, Berinderjeet

2014-01-01

The evolution of Singapore's school mathematics curriculum is in tandem with developments in the education system of Singapore. In the last six decades, economic policies of the government that are necessary for the survival of Singapore in a fast changing world have shaped the aims of the school mathematics curriculum. The present day curriculum…

6 CFR 5.21 - Requests for access to records.

Code of Federal Regulations, 2011 CFR

2011-01-01

... accessed electronically at the Government Printing Office's World Wide Web site (which can be found at http... Printing Office's World Wide Web site (which can be found at http://www.access.gpo.gov/su_docs). (c... requested records, you may also, at your option, include your social security number. (e) Verification of...

28 CFR 16.41 - Requests for access to records.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the Government Printing Office's World Wide Web site (which can be found at http://www.access.gpo.gov... accessed electronically at the Government Printing Office's World Wide Web site (which can be found at http... requested records, you may also, at your option, include your social security number. (e) Verification of...

6 CFR 5.21 - Requests for access to records.

Code of Federal Regulations, 2010 CFR

2010-01-01

... accessed electronically at the Government Printing Office's World Wide Web site (which can be found at http... Printing Office's World Wide Web site (which can be found at http://www.access.gpo.gov/su_docs). (c... requested records, you may also, at your option, include your social security number. (e) Verification of...

28 CFR 16.41 - Requests for access to records.

Code of Federal Regulations, 2011 CFR

2011-07-01

... the Government Printing Office's World Wide Web site (which can be found at http://www.access.gpo.gov... accessed electronically at the Government Printing Office's World Wide Web site (which can be found at http... requested records, you may also, at your option, include your social security number. (e) Verification of...

Fire-Walking

ERIC Educational Resources Information Center

Willey, David

2010-01-01

This article gives a brief history of fire-walking and then deals with the physics behind fire-walking. The author has performed approximately 50 fire-walks, took the data for the world's hottest fire-walk and was, at one time, a world record holder for the longest fire-walk (www.dwilley.com/HDATLTW/Record_Making_Firewalks.html). He currently…

World Myths & Legends in Art.

ERIC Educational Resources Information Center

2002

Myths are stories that explain why the world is the way it is. All cultures have them. Throughout history, artists have been inspired by myths and legends and have given them visual form. Sometimes these works of art are the only surviving record of what particular cultures believed and valued. But even where written records or oral traditions…

Player guild dynamics and evolution in massively multiplayer online games.

PubMed

Chen, Chien-Hsun; Sun, Chuen-Tsai; Hsieh, Jilung

2008-06-01

In the latest versions of massively multiplayer online games (MMOGs), developers have purposefully made guilds part of game environments. Guilds represent a powerful method for giving players a sense of online community, but there is little quantitative data on guild dynamics. To address this topic, we took advantage of a feature found in one of today's most popular MMOGs (World of Warcraft) to collect in-game data: user interfaces that players can modify and refine. In addition to collecting data on in-game player activities, we used this feature to observe and investigate how players join and leave guilds. Data were analyzed for the purpose of identifying factors that propel game-world guild dynamics and evolution. After collecting data for 641,805 avatars on 62 Taiwanese World of Warcraft game servers between February 10 and April 10, 2006, we created five guild type categories (small, large, elite, newbie, and unstable) that have different meanings in terms of in-game group dynamics. By viewing players as the most important resource affecting guild life cycles, it is possible to analyze game worlds as ecosystems consisting of evolving guilds and to study how guild life cycles reflect game world characteristics.

The 1st Symposium on Chemical Evolution and the Origin and Evolution of Life

NASA Technical Reports Server (NTRS)

Devincenzi, D. L. (Editor); Pleasant, L. G. (Editor)

1982-01-01

This symposium provided an opportunity for all NASA Exobiology principal investigators to present their most recent research in a scientific meeting forum. Papers were presented in the following exobiology areas: extraterrestrial chemistry primitive earth, information transfer, solar system exploration, planetary protection, geological record, and early biological evolution.

The sustainability of habitability on terrestrial planets: Insights, questions, and needed measurements from Mars for understanding the evolution of Earth-like worlds

NASA Astrophysics Data System (ADS)

Ehlmann, B. L.; Anderson, F. S.; Andrews-Hanna, J.; Catling, D. C.; Christensen, P. R.; Cohen, B. A.; Dressing, C. D.; Edwards, C. S.; Elkins-Tanton, L. T.; Farley, K. A.; Fassett, C. I.; Fischer, W. W.; Fraeman, A. A.; Golombek, M. P.; Hamilton, V. E.; Hayes, A. G.; Herd, C. D. K.; Horgan, B.; Hu, R.; Jakosky, B. M.; Johnson, J. R.; Kasting, J. F.; Kerber, L.; Kinch, K. M.; Kite, E. S.; Knutson, H. A.; Lunine, J. I.; Mahaffy, P. R.; Mangold, N.; McCubbin, F. M.; Mustard, J. F.; Niles, P. B.; Quantin-Nataf, C.; Rice, M. S.; Stack, K. M.; Stevenson, D. J.; Stewart, S. T.; Toplis, M. J.; Usui, T.; Weiss, B. P.; Werner, S. C.; Wordsworth, R. D.; Wray, J. J.; Yingst, R. A.; Yung, Y. L.; Zahnle, K. J.

2016-10-01

What allows a planet to be both within a potentially habitable zone and sustain habitability over long geologic time? With the advent of exoplanetary astronomy and the ongoing discovery of terrestrial-type planets around other stars, our own solar system becomes a key testing ground for ideas about what factors control planetary evolution. Mars provides the solar system's longest record of the interplay of the physical and chemical processes relevant to habitability on an accessible rocky planet with an atmosphere and hydrosphere. Here we review current understanding and update the timeline of key processes in early Mars history. We then draw on knowledge of exoplanets and the other solar system terrestrial planets to identify six broad questions of high importance to the development and sustaining of habitability (unprioritized): (1) Is small planetary size fatal? (2) How do magnetic fields influence atmospheric evolution? (3) To what extent does starting composition dictate subsequent evolution, including redox processes and the availability of water and organics? (4) Does early impact bombardment have a net deleterious or beneficial influence? (5) How do planetary climates respond to stellar evolution, e.g., sustaining early liquid water in spite of a faint young Sun? (6) How important are the timescales of climate forcing and their dynamical drivers? Finally, we suggest crucial types of Mars measurements (unprioritized) to address these questions: (1) in situ petrology at multiple units/sites; (2) continued quantification of volatile reservoirs and new isotopic measurements of H, C, N, O, S, Cl, and noble gases in rocks that sample multiple stratigraphic sections; (3) radiometric age dating of units in stratigraphic sections and from key volcanic and impact units; (4) higher-resolution measurements of heat flux, subsurface structure, and magnetic field anomalies coupled with absolute age dating. Understanding the evolution of early Mars will feed forward to understanding the factors driving the divergent evolutionary paths of the Earth, Venus, and thousands of small rocky extrasolar planets yet to be discovered.

The Sustainability of Habitability on Terrestrial Planets: Insights, Questions, and Needed Measurements from Mars for Understanding the Evolution of Earth-Like Worlds

NASA Technical Reports Server (NTRS)

Ehlmann, B. L.; Anderson, F. S.; Andrews-Hanna, J.; Catling, D. C.; Christensen, P. R.; Cohen, B. A.; Dressing, C. D.; Edwards, C. S.; Elkins-Tanton, L. T.; Farley, K. A.;

Workstation Segment Specification for the World-Wide Military Command and Control (WWMCCS) Information System (WIS)

DTIC Science & Technology

1989-07-01

software eventually, and which indicate the general thrust of evolution and growth capabilities required of the workstation segment. These GRAY sections...configuration control over the evolution of the system. (" - The transition from the WWMCCS Standard ADP system to WIS will be gradual and will be...has been designed to support the workstation needs required for most WIS users, and is the workstation that will support the long-term evolution of

Sex differences in elite swimming with advanced age are less than marathon running.

PubMed

Senefeld, J; Joyner, M J; Stevens, A; Hunter, S K

2016-01-01

The sex difference in marathon performance increases with finishing place and age of the runner but whether this occurs among swimmers is unknown. The purpose was to compare sex differences in swimming velocity across world record place (1st-10th), age group (25-89 years), and event distance. We also compared sex differences between freestyle swimming and marathon running. The world's top 10 swimming times of both sexes for World Championship freestyle stroke, backstroke, breaststroke, and butterfly events and the world's top 10 marathon times in 5-year age groups were obtained. Men were faster than women for freestyle (12.4 ± 4.2%), backstroke (12.8 ± 3.0%), and breaststroke (14.5 ± 3.2%), with the greatest sex differences for butterfly (16.7 ± 5.5%). The sex difference in swimming velocity increased across world record place for freestyle (P < 0.001), breaststroke, and butterfly for all age groups and distances (P < 0.001) because of a greater relative drop-off between first and 10th place for women. The sex difference in marathon running increased with the world record place and the sex difference for marathon running was greater than for swimming (P < 0.001). The sex difference in swimming increased with world record place and age, but was less than for marathon running. Collectively, these results suggest more depth in women's swimming than marathon running. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Parallel and convergent evolution of the dim-light vision gene RH1 in bats (Order: Chiroptera).

PubMed

Shen, Yong-Yi; Liu, Jie; Irwin, David M; Zhang, Ya-Ping

2010-01-21

Rhodopsin, encoded by the gene Rhodopsin (RH1), is extremely sensitive to light, and is responsible for dim-light vision. Bats are nocturnal mammals that inhabit poor light environments. Megabats (Old-World fruit bats) generally have well-developed eyes, while microbats (insectivorous bats) have developed echolocation and in general their eyes were degraded, however, dramatic differences in the eyes, and their reliance on vision, exist in this group. In this study, we examined the rod opsin gene (RH1), and compared its evolution to that of two cone opsin genes (SWS1 and M/LWS). While phylogenetic reconstruction with the cone opsin genes SWS1 and M/LWS generated a species tree in accord with expectations, the RH1 gene tree united Pteropodidae (Old-World fruit bats) and Yangochiroptera, with very high bootstrap values, suggesting the possibility of convergent evolution. The hypothesis of convergent evolution was further supported when nonsynonymous sites or amino acid sequences were used to construct phylogenies. Reconstructed RH1 sequences at internal nodes of the bat species phylogeny showed that: (1) Old-World fruit bats share an amino acid change (S270G) with the tomb bat; (2) Miniopterus share two amino acid changes (V104I, M183L) with Rhinolophoidea; (3) the amino acid replacement I123V occurred independently on four branches, and the replacements L99M, L266V and I286V occurred each on two branches. The multiple parallel amino acid replacements that occurred in the evolution of bat RH1 suggest the possibility of multiple convergences of their ecological specialization (i.e., various photic environments) during adaptation for the nocturnal lifestyle, and suggest that further attention is needed on the study of the ecology and behavior of bats.

Parallel and Convergent Evolution of the Dim-Light Vision Gene RH1 in Bats (Order: Chiroptera)

PubMed Central

Shen, Yong-Yi; Liu, Jie; Irwin, David M.; Zhang, Ya-Ping

2010-01-01

Rhodopsin, encoded by the gene Rhodopsin (RH1), is extremely sensitive to light, and is responsible for dim-light vision. Bats are nocturnal mammals that inhabit poor light environments. Megabats (Old-World fruit bats) generally have well-developed eyes, while microbats (insectivorous bats) have developed echolocation and in general their eyes were degraded, however, dramatic differences in the eyes, and their reliance on vision, exist in this group. In this study, we examined the rod opsin gene (RH1), and compared its evolution to that of two cone opsin genes (SWS1 and M/LWS). While phylogenetic reconstruction with the cone opsin genes SWS1 and M/LWS generated a species tree in accord with expectations, the RH1 gene tree united Pteropodidae (Old-World fruit bats) and Yangochiroptera, with very high bootstrap values, suggesting the possibility of convergent evolution. The hypothesis of convergent evolution was further supported when nonsynonymous sites or amino acid sequences were used to construct phylogenies. Reconstructed RH1 sequences at internal nodes of the bat species phylogeny showed that: (1) Old-World fruit bats share an amino acid change (S270G) with the tomb bat; (2) Miniopterus share two amino acid changes (V104I, M183L) with Rhinolophoidea; (3) the amino acid replacement I123V occurred independently on four branches, and the replacements L99M, L266V and I286V occurred each on two branches. The multiple parallel amino acid replacements that occurred in the evolution of bat RH1 suggest the possibility of multiple convergences of their ecological specialization (i.e., various photic environments) during adaptation for the nocturnal lifestyle, and suggest that further attention is needed on the study of the ecology and behavior of bats. PMID:20098620

Conference on Early Mars: Geologic and Hydrologic Evolution, Physical and Chemical Environments, and the Implications for Life

NASA Technical Reports Server (NTRS)

Clifford, S. M. (Editor); Treiman, A. H. (Editor); Newsom, H. E. (Editor); Farmer, J. D. (Editor)

1997-01-01

Topics considered include: Geology alteration and life in an extreme environment; developing a chemical code to identify magnetic biominerals; effect of impacts on early Martin geologic evolution; spectroscopic identification of minerals in Hematite-bearing soils and sediments; exopaleontology and the search for a Fossil record on Mars; geochemical evolution of the crust of Mars; geological evolution of the early earth;solar-wind-induced erosion of the Mars atmosphere. Also included geological evolution of the crust of Mars.

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

Gergely, Laszlo A.

We study the possibility of brane-world generalization of the Einstein-Straus Swiss-cheese cosmological model. We find that the modifications induced by the brane-world scenario are excessively restrictive. At a first glance only the motion of the boundary is modified and the fluid in the exterior region is allowed to have pressure. The general relativistic Einstein-Straus model emerges in the low density limit. However by imposing that the central mass in the Schwarzschild voids is constant, a combination of the junction conditions and modified cosmological evolution leads to the conclusion that the brane is flat. Thus no generic Swiss-cheese universe can existmore » on the brane. The conclusion is not altered by the introduction of a cosmological constant in the FLRW regions. This shows that although allowed in the low density limit, the Einstein-Straus universe cannot emerge from cosmological evolution in the brane-world scenario.« less

Continuously growing rodent molars result from a predictable quantitative evolutionary change over 50 million years

PubMed Central

Mushegyan, Vagan; Eronen, Jussi T.; Lawing, A. Michelle; Sharir, Amnon; Janis, Christine; Jernvall, Jukka; Klein, Ophir D.

2015-01-01

Summary The fossil record is widely informative about evolution, but fossils are not systematically used to study the evolution of stem cell-driven renewal. Here, we examined evolution of the continuous growth (hypselodonty) of rodent molar teeth, which is fuelled by the presence of dental stem cells. We studied occurrences of 3500 North American rodent fossils, ranging from 50 million years ago (mya) to 2 mya. We examined changes in molar height to determine if evolution of hypselodonty shows distinct patterns in the fossil record, and we found that hypselodont taxa emerged through intermediate forms of increasing crown height. Next, we designed a Markov simulation model, which replicated molar height increases throughout the Cenozoic, and, moreover, evolution of hypselodonty. Thus, by extension, the retention of the adult stem-cell niche appears to be a predictable quantitative rather than a stochastic qualitative process. Our analyses predict that hypselodonty will eventually become the dominant phenotype. PMID:25921530

What Does “the RNA World” Mean to “the Origin of Life”?

PubMed Central

Ma, Wentao

2017-01-01

Corresponding to life’s two distinct aspects: Darwinian evolution and self-sustainment, the origin of life should also split into two issues: the origin of Darwinian evolution and the arising of self-sustainment. Because the “self-sustainment” we concern about life should be the self-sustainment of a relevant system that is “defined” by its genetic information, the self-sustainment could not have arisen before the origin of Darwinian evolution, which was just marked by the emergence of genetic information. The logic behind the idea of the RNA world is not as tenable as it has been believed. That is, genetic molecules and functional molecules, even though not being the same material, could have emerged together in the beginning and launched the evolution—provided that the genetic molecules can “simply” code the functional molecules. However, due to these or those reasons, alternative scenarios are generally much less convincing than the RNA world. In particular, when considering the accumulating experimental evidence that is supporting a de novo origin of the RNA world, it seems now quite reasonable to believe that such a world may have just stood at the very beginning of life on the Earth. Therewith, we acquire a concrete scenario for our attempts to appreciate those fundamental issues that are involved in the origin of life. In the light of those possible scenes included in this scenario, Darwinian evolution may have originated at the molecular level, realized upon a functional RNA. When two or more functional RNAs emerged, for their efficient cooperation, there should have been a selective pressure for the emergence of protocells. But it was not until the appearance of the “unitary-protocell”, which had all of its RNA genes linked into a chromosome, that Darwinian evolution made its full step towards the cellular level—no longer severely constrained by the low-grade evolution at the molecular level. Self-sustainment did not make sense before protocells emerged. The selection pressure that was favoring the exploration of more and more fundamental raw materials resulted in an evolutionary tendency of life to become more and more self-sustained. New functions for the entities to adapt to environments, including those that are involved in the self-sustainment per se, would bring new burdens to the self-sustainment—the advantage of these functions must overweigh the corresponding disadvantage. PMID:29186049

Montmorillonite protection of an UV-irradiated hairpin ribozyme: evolution of the RNA world in a mineral environment

PubMed Central

Biondi, Elisa; Branciamore, Sergio; Maurel, Marie-Christine; Gallori, Enzo

2007-01-01

Background The hypothesis of an RNA-based origin of life, known as the "RNA world", is strongly affected by the hostile environmental conditions probably present in the early Earth. In particular, strong UV and X-ray radiations could have been a major obstacle to the formation and evolution of the first biomolecules. In 1951, J. D. Bernal first proposed that clay minerals could have served as the sites of accumulation and protection from degradation of the first biopolymers, providing the right physical setting for the evolution of more complex systems. Numerous subsequent experimental studies have reinforced this hypothesis. Results The ability of the possibly widespread prebiotic, clay mineral montmorillonite to protect the catalytic RNA molecule ADHR1 (Adenine Dependent Hairpin Ribozyme 1) from UV-induced damages was experimentally checked. In particular, the self-cleavage reaction of the ribozyme was evaluated after UV-irradiation of the molecule in the absence or presence of clay particles. Results obtained showed a three-fold retention of the self-cleavage activity of the montmorillonite-protected molecule, with respect to the same reaction performed by the ribozyme irradiated in the absence of the clay. Conclusion These results provide a suggestion with which RNA, or RNA-like molecules, could have overcame the problem of protection from UV irradiation in the RNA world era, and suggest that a clay-rich environment could have favoured not only the formation of first genetic molecules, but also their evolution towards increasingly complex molecular organization. PMID:17767730

The Spatial and Temporal Distribution of SST in the Yellow Sea and the Evolution of the Yellow Sea Warm Current During the Holocene

NASA Astrophysics Data System (ADS)

Jia, Y.; Xiao, X.; Yu, M.; Yuan, Z. N.; Zhang, H.; Zhao, M.

2017-12-01

The Yellow Sea (YS) environment is influenced by both continental and oceanic forcing. The Yellow Sea Warm Current (YSWC) is the most significantly hydrological characteristics of the YS in winter, which is a conduit by which the deep Pacific Ocean influences the YS. Paleo-environmental records are essential for understanding the evolution of the YS environment, especially the spatial distribution of the sea surface temperature (SST) records which can be used to interpret the controlling factors of the YSWC. Previous studies mostly focused on the temporal variation but studies on both temporal and spatial environmental evolution are rather sparse. We used Uk37 temperature records in 9 cores located the north of 35°N in YS to reconstruct the spatial/temporal variations of the SST during the Holocene and further to understand the main natural factors that influenced the evolution of the YS environment and current system. All the SST records in 9 sediment cores displayed the similar trend during the Holocene, showing a regional response to marine environmental variability in the east China Seas influenced by the YSWC. To reconstruct the historical westward shift of the YSWC relative to the bathymetric trough of the YS, we compared SST records of the cores located in the west and east side of the axis of the modern YSWC. The obvious westward shift of the YSWC was observed during the periods of 4500-5000aBP, 2800-3400aBP and 1600-0aBP, especially 1000-0aBP, indicating by the distinctly gradual temperature gradients. The comparison of the East Asian Winter Monsoon(EAWM) and the Kuroshio current intensity records with the SST records revealed that the westward shift of the YSWC might be controlled by the Kuroshio intensity. Our findings have important implications for understanding the mechanisms of the variability of the YSWC.

Statistical geochemistry reveals disruption in secular lithospheric evolution about 2.5 Gyr ago.

PubMed

Keller, C Brenhin; Schoene, Blair

2012-05-23

The Earth has cooled over the past 4.5 billion years (Gyr) as a result of surface heat loss and declining radiogenic heat production. Igneous geochemistry has been used to understand how changing heat flux influenced Archaean geodynamics, but records of systematic geochemical evolution are complicated by heterogeneity of the rock record and uncertainties regarding selection and preservation bias. Here we apply statistical sampling techniques to a geochemical database of about 70,000 samples from the continental igneous rock record to produce a comprehensive record of secular geochemical evolution throughout Earth history. Consistent with secular mantle cooling, compatible and incompatible elements in basalts record gradually decreasing mantle melt fraction through time. Superimposed on this gradual evolution is a pervasive geochemical discontinuity occurring about 2.5 Gyr ago, involving substantial decreases in mantle melt fraction in basalts, and in indicators of deep crustal melting and fractionation, such as Na/K, Eu/Eu* (europium anomaly) and La/Yb ratios in felsic rocks. Along with an increase in preserved crustal thickness across the Archaean/Proterozoic boundary, these data are consistent with a model in which high-degree Archaean mantle melting produced a thick, mafic lower crust and consequent deep crustal delamination and melting--leading to abundant tonalite-trondhjemite-granodiorite magmatism and a thin preserved Archaean crust. The coincidence of the observed changes in geochemistry and crustal thickness with stepwise atmospheric oxidation at the end of the Archaean eon provides a significant temporal link between deep Earth geochemical processes and the rise of atmospheric oxygen on the Earth.

Army Aviation’s Pacific Rebalance: Evolution Towards Maritime Operations

DTIC Science & Technology

2016-05-26

Training and Doctrine Command Pamphlet (TRADOC PAM) 525-3-1, The US Army Operating Concept: Win in a Complex World 2020-2040 (Washington, DC...influence.81 Figure 3. East Timor in the South Indian Ocean Source: “Indonesia” (map), CIA World Factbook, accessed 2 March 2016, https://www. cia.gov...library/publications/resources/the- world -factbook/geos/id.html. In 1975, Indonesia invaded and annexed the Portuguese colony, Timor Island

The Evolution of Malaysias Immigration Policy Since 1970

DTIC Science & Technology

2015-03-01

The State of the ‘State’ in Globalization: Social Order and Economic Restructuring in Malaysia,” Third World Quarterly 21, no. 6 (2000): 1047. 5...remittance industry.10 In 2009, Malaysia qualified as one to the top remittance-sending countries in the world , with over $6.8 billion (3 percent of...50–51. 10 International Bank for Reconstruction and Development, Migration and Remittances Factbook 2011 (Washington, DC: World Bank, 2011), 13

Evolution of weighted complex bus transit networks with flow

NASA Astrophysics Data System (ADS)

Huang, Ailing; Xiong, Jie; Shen, Jinsheng; Guan, Wei

2016-02-01

Study on the intrinsic properties and evolutional mechanism of urban public transit networks (PTNs) has great significance for transit planning and control, particularly considering passengers’ dynamic behaviors. This paper presents an empirical analysis for exploring the complex properties of Beijing’s weighted bus transit network (BTN) based on passenger flow in L-space, and proposes a bi-level evolution model to simulate the development of transit routes from the view of complex network. The model is an iterative process that is driven by passengers’ travel demands and dual-controlled interest mechanism, which is composed of passengers’ spatio-temporal requirements and cost constraint of transit agencies. Also, the flow’s dynamic behaviors, including the evolutions of travel demand, sectional flow attracted by a new link and flow perturbation triggered in nearby routes, are taken into consideration in the evolutional process. We present the numerical experiment to validate the model, where the main parameters are estimated by using distribution functions that are deduced from real-world data. The results obtained have proven that our model can generate a BTN with complex properties, such as the scale-free behavior or small-world phenomenon, which shows an agreement with our empirical results. Our study’s results can be exploited to optimize the real BTN’s structure and improve the network’s robustness.

Seasonal and interannual evolution of Jakobshavn Isbrae, Greenland from a 2008-2015 high-res DEM and velocity time series

NASA Astrophysics Data System (ADS)

Shean, D. E.; Joughin, I.; Smith, B.; Floricioiu, D.

2015-12-01

Greenland's large marine-terminating outlet glaciers have displayed marked retreat, speedup, and thinning in recent decades. Jakobshavn Isbrae, one of Greenland's largest outlet glaciers, has retreated ~15 km, accelerated ~150%, and thinned ~200 m since the early 1990s. Here, we present a comprehensive analysis of high-resolution elevation (~2-5 m/px) and velocity (~100 m/px) time series with dense temporal coverage (daily-monthly). The Jakobshavn DEM time series consists of >70 WorldView-1/2/3 stereo DEMs and >11 TanDEM-X DEMs spanning 2008-2015. Complementary point elevation data from Operation IceBridge (ATM, LVIS), pre-IceBridge ATM flights, and ICESat-1 GLAS extend the surface elevation record to 1999 and provide essential absolute control data, enabling sub-meter horizontal/vertical accuracy for gridded DEMs. Velocity data are primarily derived from TerraSAR-X/TanDEM-X image pairs with 11-day interval from 2009-2015. These elevation and velocity data capture outlet glacier evolution with unprecedented detail during the post-ICESat era. The lower trunk of Jakobshavn displays significant seasonal velocity variations, with recent rates of ~8 km/yr during winter and >17 km/yr during summer. DEM data show corresponding seasonal elevation changes of -30 to -45 m in summer and +15 to +20 m in winter, with decreasing magnitude upstream. Seasonal discharge varies from ~30-35 Gt/yr in winter to ~45-55 Gt/yr in summer, and we integrate these measurements for improved long-term mass-balance estimates. Recent interannual trends show increased discharge, velocity, and thinning (-15 to -20 m/yr), which is consistent with long-term altimetry records. The DEM time series also reveal new details about calving front and mélange evolution during the seasonal cycle. Similar time series are available for Kangerdlugssuaq and Helheim Glaciers. These observations are improving our understanding of outlet glacier dynamics, while complementing ongoing efforts to constrain estimates for ice-sheet mass balance and present/future sea level rise contributions.

The Evolution and Practice of Institutional Research

ERIC Educational Resources Information Center

Taylor, John; Hanlon, Martin; Yorke, Mantz

2013-01-01

Although institutional research has been a significant feature of U.S. higher education for more than 50 years, it is not so well understood in other parts of the world. As higher education around the world faces increasingly challenging times in responding to pressures of massification and globalization, increasing forms of accountability and…

Design Principles for "Thriving in Our Digital World": A High School Computer Science Course

ERIC Educational Resources Information Center

Veletsianos, George; Beth, Bradley; Lin, Calvin; Russell, Gregory

2016-01-01

"Thriving in Our Digital World" is a technology-enhanced dual enrollment course introducing high school students to computer science through project- and problem-based learning. This article describes the evolution of the course and five lessons learned during the design, development, implementation, and iteration of the course from its…

Science and Religion: What Is at Stake?

ERIC Educational Resources Information Center

Roth, Wolff-Michael

2010-01-01

There are some who experience irreconcilable differences between their religious beliefs concerning a world created as is, on the one hand, and a scientific view of the world that has developed by means of natural evolution over billions of years, on the other hand. In this special issue, scholars from very different religions, backgrounds, and…

The World in Microcosm: From John Dewey to Global Perspectives.

ERIC Educational Resources Information Center

Peters, Richard

By tracing major ideas in the evolution of educational history between 1899 and 1985, the document takes readers from the traditional emphasis on citizenship training in social education to the current focus on teaching about the world community and the interdependence of its people and systems--cultural, ecological, economic, linguistic, racial,…

Foreign Language Anxiety Levels in Second Life Oral Interaction

ERIC Educational Resources Information Center

Melchor-Couto, Sabela

2017-01-01

Virtual worlds have been described as low anxiety environments (Dickey, 2005), where students may feel "shielded" behind their avatars (Rosell-Aguilar, 2005: 432). The aim of this article is to analyse the evolution of the Foreign Language Anxiety (FLA) levels experienced by a group of participants who used the virtual world "Second…

"The Evolution of e-Learning in the Context of 3D Virtual Worlds"

ERIC Educational Resources Information Center

Kotsilieris, Theodore; Dimopoulou, Nikoletta

2013-01-01

Information and Communication Technologies (ICT) offer new approaches towards knowledge acquisition and collaboration through distance learning processes. Web-based Learning Management Systems (LMS) have transformed the way that education is conducted nowadays. At the same time, the adoption of Virtual Worlds in the educational process is of great…

Education and Disarmament.

ERIC Educational Resources Information Center

Greene, Maxine

1982-01-01

Education should release humans to reach out from their own places in the world so that they can make sense of how they live and what they encounter around themselves. This sort of education, which will "humanize" the world and populate it with "self-understanding" citizens, will allow for the evolution of alternatives to destruction and war. (CJ)

Is Boron a Prebiotic Element? A Mini-review of the Essentiality of Boron for the Appearance of Life on Earth

NASA Astrophysics Data System (ADS)

Scorei, Romulus

2012-02-01

Boron is probably a prebiotic element with special importance in the so-called "sugars world". Boron is not present on Earth in its elemental form. It is found only in compounds, e.g., borax, boric acid, kernite, ulexite, colemanite and other borates. Volcanic spring waters sometimes contain boron-based acids (e.g., boric, metaboric, tetraboric and pyroboric acid). Borates influence the formation of ribofuranose from formaldehyde that feeds the "prebiotic metabolic cycle". The importance of boron in the living world is strongly related to its implications in the prebiotic origins of genetic material; consequently, we believe that throughout the evolution of life, the primary role of boron has been to provide thermal and chemical stability in hostile environments. The complexation of boric acid and borates with organic cis-diols remains the most probable chemical mechanism for the role of this element in the evolution of the living world. Because borates can stabilize ribose and form borate ester nucleotides, boron may have provided an essential contribution to the "pre-RNA world".

The Epidemiological Scale of Alzheimer’s Disease

PubMed Central

Cornutiu, Gavril

2015-01-01

Alzheimer’s disease (AD) has increased from a few cases in a country at the beginning of the 20th century to an incidence of recording a case every 7 seconds in the world. From a rare disease it has reached the top 8 of major health problems in the world. One of the epidemiological problems of AD is the fact that authors from different countries use different reporting units. Some report numbers to 100,000 inhabitants, others to 1,000 inhabitants and others report the total number of cases in a country. Standardization of these reports is strictly necessary. The rise in incidence and prevalence with age is known, but interesting to see is that the incidence and prevalence do not rise in a parallel manner with age as simple logic would assume. Between the ages of 60 and 90, the incidence in men increases two times and in women 41 times, prevalence increase in men is 55.25-fold and in women 77-fold. Regarding the women/men ratio, the incidence is 20.5-fold increased, and prevalence is merely 1.3936-fold increased. These numbers raise concerns about the evolution of the disease. Regarding mild cognitive impairment (MCI)/AD ratio, only about 1 in 2 people get AD (raising?) issues about the pathogenic disease relatedness. PMID:26251678

Altered characteristic of brain networks in mild cognitive impairment during a selective attention task: An EEG study.

PubMed

Wei, Ling; Li, Yingjie; Yang, Xiaoli; Xue, Qing; Wang, Yuping

2015-10-01

The present study evaluated the topological properties of whole brain networks using graph theoretical concepts and investigated the time-evolution characteristic of brain network in mild cognitive impairment patients during a selective attention task. Electroencephalography (EEG) activities were recorded in 10 MCI patients and 17 healthy subjects when they performed a color match task. We calculated the phase synchrony index between each possible pairs of EEG channels in alpha and beta frequency bands and analyzed the local interconnectedness, overall connectedness and small-world characteristic of brain network in different degree for two groups. Relative to healthy normal controls, the properties of cortical networks in MCI patients tend to be a shift of randomization. Lower σ of MCI had suggested that patients had a further loss of small-world attribute both during active and resting states. Our results provide evidence for the functional disconnection of brain regions in MCI. Furthermore, we found the properties of cortical networks could reflect the processing of conflict information in the selective attention task. The human brain tends to be a more regular and efficient neural architecture in the late stage of information processing. In addition, the processing of conflict information needs stronger information integration and transfer between cortical areas. Copyright © 2015 Elsevier B.V. All rights reserved.

Ocean Worlds Analog Systems in the Hadal Ocean: Systematic Examination of Pressure, Food Supply, Topography, and Evolution on Hadal Life

NASA Astrophysics Data System (ADS)

Shank, T. M.; German, C.; Machado, C.; Bowen, A.; Drazen, J.; Yancey, P.; Jamieson, A.; Rowden, A.; Clark, M.; Heyl, T.; Mayor, D.; Piertney, S.; Ruhl, H.

2018-05-01

Key questions on life’s evolution are being pursued in Earth’s hadal ocean, Earth’s only analog to Europa’s ocean. A recent WHOI-JPL partnership is developing an armada of autonomous underwater drone vehicles to explore of Earth’s and Europa’s oceans.

Rank-dependent deactivation in network evolution.

PubMed

Xu, Xin-Jian; Zhou, Ming-Chen

2009-12-01

A rank-dependent deactivation mechanism is introduced to network evolution. The growth dynamics of the network is based on a finite memory of individuals, which is implemented by deactivating one site at each time step. The model shows striking features of a wide range of real-world networks: power-law degree distribution, high clustering coefficient, and disassortative degree correlation.

Reedy Creek Cleanup: The Evolution of a University Geography Service-Learning Project

ERIC Educational Resources Information Center

Parece, Tammy E.; Aspaas, Helen Ruth

2007-01-01

Service-learning courses within a university setting help students to better understand their roles as members of civil society. This article examines the evolution of an urban stream cleanup project that has been part of a world regions geography course for six years. After connecting course goals with the current best practice literature on…

A Course in Evolutionary Biology: Engaging Students in the "Practice" of Evolution. Research Report.

ERIC Educational Resources Information Center

Passmore, Cynthia; Stewart, James

Recent education reform documents emphasize the need for students to develop a rich understanding of evolution's power to integrate knowledge of the natural world. This paper describes a nine-week high school course designed to help students understand evolutionary biology by engaging them in developing, elaborating, and using Charles Darwin's…

Extant-only comparative methods fail to recover the disparity preserved in the bird fossil record.

PubMed

Mitchell, Jonathan S

2015-09-01

Most extant species are in clades with poor fossil records, and recent studies of comparative methods show they have low power to infer even highly simplified models of trait evolution without fossil data. Birds are a well-studied radiation, yet their early evolutionary patterns are still contentious. The fossil record suggests that birds underwent a rapid ecological radiation after the end-Cretaceous mass extinction, and several smaller, subsequent radiations. This hypothesized series of repeated radiations from fossil data is difficult to test using extant data alone. By uniting morphological and phylogenetic data on 604 extant genera of birds with morphological data on 58 species of extinct birds from 50 million years ago, the "halfway point" of avian evolution, I have been able to test how well extant-only methods predict the diversity of fossil forms. All extant-only methods underestimate the disparity, although the ratio of within- to between-clade disparity does suggest high early rates. The failure of standard models to predict high early disparity suggests that recent radiations are obscuring deep time patterns in the evolution of birds. Metrics from different models can be used in conjunction to provide more valuable insights than simply finding the model with the highest relative fit. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

Adaptive Evolution of the Myo6 Gene in Old World Fruit Bats (Family: Pteropodidae)

PubMed Central

Shen, Bin; Han, Xiuqun; Jones, Gareth; Rossiter, Stephen J.; Zhang, Shuyi

2013-01-01

Myosin VI (encoded by the Myo6 gene) is highly expressed in the inner and outer hair cells of the ear, retina, and polarized epithelial cells such as kidney proximal tubule cells and intestinal enterocytes. The Myo6 gene is thought to be involved in a wide range of physiological functions such as hearing, vision, and clathrin-mediated endocytosis. Bats (Chiroptera) represent one of the most fascinating mammal groups for molecular evolutionary studies of the Myo6 gene. A diversity of specialized adaptations occur among different bat lineages, such as echolocation and associated high-frequency hearing in laryngeal echolocating bats, large eyes and a strong dependence on vision in Old World fruit bats (Pteropodidae), and specialized high-carbohydrate but low-nitrogen diets in both Old World and New World fruit bats (Phyllostomidae). To investigate what role(s) the Myo6 gene might fulfill in bats, we sequenced the coding region of the Myo6 gene in 15 bat species and used molecular evolutionary analyses to detect evidence of positive selection in different bat lineages. We also conducted real-time PCR assays to explore the expression levels of Myo6 in a range of tissues from three representative bat species. Molecular evolutionary analyses revealed that the Myo6 gene, which was widely considered as a hearing gene, has undergone adaptive evolution in the Old World fruit bats which lack laryngeal echolocation and associated high-frequency hearing. Real-time PCR showed the highest expression level of the Myo6 gene in the kidney among ten tissues examined in three bat species, indicating an important role for this gene in kidney function. We suggest that Myo6 has undergone adaptive evolution in Old World fruit bats in relation to receptor-mediated endocytosis for the preservation of protein and essential nutrients. PMID:23620821

Complex networks generated by the Penna bit-string model: Emergence of small-world and assortative mixing

NASA Astrophysics Data System (ADS)

Li, Chunguang; Maini, Philip K.

2005-10-01

The Penna bit-string model successfully encompasses many phenomena of population evolution, including inheritance, mutation, evolution, and aging. If we consider social interactions among individuals in the Penna model, the population will form a complex network. In this paper, we first modify the Verhulst factor to control only the birth rate, and introduce activity-based preferential reproduction of offspring in the Penna model. The social interactions among individuals are generated by both inheritance and activity-based preferential increase. Then we study the properties of the complex network generated by the modified Penna model. We find that the resulting complex network has a small-world effect and the assortative mixing property.

Earthscape: Transitions toward World Order. The Whole Earth Papers, No. 12.

ERIC Educational Resources Information Center

Mische, Patricia; And Others

The five articles in this booklet focus on positive social, political, and economic responses to world problems. The first article, "Earthscape: Transitions Toward World Order," by Patricia Mische, outlines major biological, historical, and cultural transformations which the world has undergone since the beginnings of recorded history and…

Accomplishments and Compromises in Prediction Research for World Records and Best Performances in Track and Field and Swimming

ERIC Educational Resources Information Center

Liu, Yuanlong; Paul, Stanley; Fu, Frank H.

2012-01-01

The conductors of this study reviewed prediction research and studied the accomplishments and compromises in predicting world records and best performances in track and field and swimming. The results of the study showed that prediction research only promises to describe the historical trends in track and field and swimming performances, to study…

Crustal evolution in Asia: Correlations and connections

NASA Astrophysics Data System (ADS)

Tsunogae, Toshiaki; Kwon, Sanghoon; Santosh, M.

2016-11-01

The Asian region records multiple subduction, accretion and collision processes related to the breakup of Gondwana and Pangea, and the ongoing formation of the future supercontinent Amasia. The oldest geological record of Asia is preserved in Archean crustal fragments which were welded together by later collisional events related to the assembly of several supercontinents. The Asian region also records recent geological events such as volcanic activities and mega-earthquakes related to subduction of oceanic plates along active continental margins and collision of microplates. This region is thus regarded as an excellent field laboratory for examining the evolution of continental crust and cratons, formation and destruction of continents and supercontinents, and related metallogenic and surface environmental processes.

Ages and Growth of the Continental Crust from Radiogenic Isotopes

NASA Astrophysics Data System (ADS)

Patchett, P. J.; Samson, S. D.

2003-12-01

The development and application of radiogenic isotopes to dating of geologic events, and to questions of growth, evolution, and recycling processes in the continental crust are mature areas of scientific inquiry. By this we understand that many of the approaches used to date rocks and constrain the evolution of the continents are well established, even routine, and that the scope of data available on age and evolution of continents is very large. This is not to say that new approaches have not been developed in recent years, or that new approaches and/or insights cannot be developed in the future. However, the science of continental crustal evolution is definitely a domain where many of the problems are well defined, the power of the techniques used to solve them are well known, and the limitations of field and laboratory databases, as well as the preserved geologic record, are understood.From the very early days of crustal evolution studies, it was innovations and improvements in laboratory techniques that drove the pace of discovery (e.g., Holmes, 1911; Nier, 1939). This remained true through all the increments in capability reviewed in this chapter, up to the present day. Thus, continental crustal evolution is an area of Earth science where a species of very laboratory-oriented investigator, the "radiogenic isotope geologist" or "geochronologist," has made major advances, even breakthroughs, in understanding. This is true in spite of the fact that many of the individuals of the species may have lacked field expertise, or even more than a primitive level of geologic background. Because design and building of instruments like radiation detectors or mass spectrometers requires a knowledge of physics, many of the early practitioners of rock dating were physicists, like Alfred Nier (cited above). Since the 1970s, essentially all mass spectrometers have been constructed by specialized commercial firms, and the level of physics expertise among isotope geologists has been lower. These firms, based mainly (but not exclusively) in and around Manchester, England, and Bremen, Germany, have spearheaded technical innovations in mass spectrometry. Isotope geology researchers are one group of consumers for this technology, along with chemists, nuclear-weapon laboratories and nuclear-power generating facilities. Today, the vast majority of isotope geology researchers are derived from geological backgrounds.This chapter will briefly review historical aspects of the development of radiogenic isotope geology as applied to continents. Some details, references and cross-references to other chapters in this volume will be provided for most major radiogenic isotopic methods, and for applications of these. However, this chapter will ultimately concentrate on two major approaches that dominate the research field today: (i) crustal tectonic and magmatic ages from U-Pb dating of accessory minerals like zircon; and (ii) crustal differentiation and growth from neodymium isotopic determinations on total rocks.The sheer amount of data available from continental areas, and the pace of data acquisition today, places any geographically constrained compilation in the impossible category for a chapter like this one. In this chapter, the state of the art in both geochronology and crustal origins will be illustrated by selected examples, not by global compilations or comprehensive discussions of each region that has been studied. Nevertheless, some remarks about the availability of data from different parts of the world need to be made. As with other areas of geology, biology, and botany, the parts of the world that have been longest settled by western civilization have the best data coverage for both ages of continental rocks, and their origins and evolution. Thus, Western Europe, Canada, the USA and Australia have generally somewhat thorough coverage. More limited data have become available from Eastern Europe, Greenland, Central and South America, Africa, Asia, and Antarctica. Some of these data have been produced by groups based in those regions, but much of the data published between 1970 and today have been driven by studies based in, and funded from, western countries. Availability of state-of-the-art results for ages of crust and its evolution are low in Antarctica and Greenland, where climate and ice cover limit work, and in South America, Africa, and parts of Asia, where studies have been sporadic, and are certainly limited in some cases by political instability. This general situation is now changing, however. Two parts of the world where results for ages of orogenic belts and for crustal evolution in general are accumulating more rapidly since about 1990 are China and Russia; this is connected with growth of modern isotope geology facilities in those countries. Understanding of global continent growth and evolution is limited in critical respects by the large regions of the world that are poorly dated. Therefore, gradual improvement of the state of knowledge of less accessible parts of the continents will bring significant benefits, even though the conceptual issues may be understood to a large extent.

The timing of events surrounding the Eocene-Oligocene boundary - Results from ODP Leg 199

NASA Astrophysics Data System (ADS)

Pälike, H.; Wilson, P. A.; Coxall, H.; Backman, J.

2003-04-01

The Eocene/Oligocene (E/O) boundary represents an extreme and rapid climatic transition from the ``greenhouse'' world of the Cretaceous and early Paleogene into the late Paleogene-Neogene ``ice-house''. It is marked by a large and global deepening in the calcite compensation depth (CCD), as well as pronounced changes in the isotopic composition of carbon and oxygen in seawater, recorded in biogenic calcium carbonate. A good understanding is still lacking as to why climatic, palaeoceanographic and marine biological productivity changes occurred within a few tens of thousands of years, and what change in boundary conditions triggered a non-linear response of the climate system. Detailed palaeoceanographic records surrounding the E/O have been rare because of the lack of well-dated, expanded deep-sea sedimentary sections containing well-preserved calcareous microfossils. Ocean Drilling Program Leg 199 recently recovered an extensive set of high-quality sediment cores across the E/O that span a latitudinal and depth transect in the central Pacific Ocean. We present new high-resolution records of bulk %CaCO3, δ18O and δ13C for a set of sites that form a depth transect, clearly delineating the relative depth with respect to the CCD during the transition. Our data show that a two-stepped deepening of the CCD coincides with a remarkably similar and simultaneous evolution of bulk δ18O values. We can demonstrate the imprint of climatic cycles around the E/O boundary, and very high-quality bio- and paleomagnetic datum points allow us to link these to Earth's orbital variations. Shipboard measurements of sediment properties and down-hole log measurements also display an imprint of climatic cycles, and allow us to obtain an astronomically calibrated time scale across the E/O. Our results put tighter constraints on the timing of the evolution of the CCD, mass accumulation rates, and biological productivity across the E/O, which display a distinct two-step shift in the most expanded section at the shallowest end of the transect (Site 1218). The initial deepening of the CCD occurred in less than 50 thousand years, and we observe a change in the nature and amplitude of climatic cycles that are recorded in sediments from Leg 199 across the E/O.

Multi-Model approach to reconstruct the Mediterranean Freshwater Evolution

NASA Astrophysics Data System (ADS)

Simon, Dirk; Marzocchi, Alice; Flecker, Rachel; Lunt, Dan; Hilgen, Frits; Meijer, Paul

2016-04-01

Today the Mediterranean Sea is isolated from the global ocean by the Strait of Gibraltar. This restricted nature causes the Mediterranean basin to react more sensitively to climatic and tectonic related phenomena than the global ocean. Not just eustatic sea-level and regional river run-off, but also gateway tectonics and connectivity between sub-basins are leaving an enhanced fingerprint in its geological record. To understand its evolution, it is crucial to understand how these different effects are coupled. The Miocene-Pliocene sedimentary record of the Mediterranean shows alternations in composition and colour and has been astronomically tuned. Around the Miocene-Pliocene Boundary the most extreme changes occur in the Mediterranean Sea. About 6% of the salt in the global ocean deposited in the Mediterranean Region, forming an approximately 2 km thick salt layer, which is still present today. This extreme event is named the Messinian Salinity Crisis (MSC, 5.97-5.33 Ma). The gateway and climate evolution is not well constrained for this time, which makes it difficult to distinguish which of the above mentioned drivers might have triggered the MSC. We, therefore, decided to tackle this problem via a multi-model approach: (1) We calculate the Mediterranean freshwater evolution via 30 atmosphere-ocean-vegetation simulations (using HadCM3L), to which we fitted to a function, using a regression model. This allows us to directly relate the orbital curves to evaporation, precipitation and run off. The resulting freshwater evolution can be directly correlated to other sedimentary and proxy records in the late Miocene. (2) By feeding the new freshwater evolution curve into a box/budget model we can predict the salinity and strontium evolution of the Mediterranean for a certain Atlantic-Mediterranean gateway. (3) By comparing these results to the known salinity thresholds of gypsum and halite saturation of sea water, but also to the late Miocene Mediterranean strontium record, we can infer how the connectivity between global ocean and the Mediterranean must have changed through time in order to cause the MSC. (4) Such a connectivity evolution will give us the basis to understand the interplay between eustatic sea-level and regional tectonic changes in the Gibraltar region. Here we present the detailed method, the results and the applications of this multi-model approach.

Holocene shifts of the southern westerlies across the South Atlantic

NASA Astrophysics Data System (ADS)

Voigt, Ines; Chiessi, Cristiano M.; Prange, Matthias; Mulitza, Stefan; Groeneveld, Jeroen; Varma, Vidya; Henrich, Ruediger

2015-02-01

The southern westerly winds (SWW) exert a crucial influence over the world ocean and climate. Nevertheless, a comprehensive understanding of the Holocene temporal and spatial evolution of the SWW remains a significant challenge due to the sparsity of high-resolution marine archives and appropriate SWW proxies. Here we present a north-south transect of high-resolution planktonic foraminiferal oxygen isotope records from the western South Atlantic. Our proxy records reveal Holocene migrations of the Brazil-Malvinas Confluence (BMC), a highly sensitive feature for changes in the position and strength of the northern portion of the SWW. Through the tight coupling of the BMC position to the large-scale wind field, the records allow a quantitative reconstruction of Holocene latitudinal displacements of the SWW across the South Atlantic. Our data reveal a gradual poleward movement of the SWW by about 1-1.5° from the early to the mid-Holocene. Afterward, variability in the SWW is dominated by millennial scale displacements on the order of 1° in latitude with no recognizable longer-term trend. These findings are confronted with results from a state-of-the-art transient Holocene climate simulation using a comprehensive coupled atmosphere-ocean general circulation model. Proxy-inferred and modeled SWW shifts compare qualitatively, but the model underestimates both orbitally forced multimillennial and internal millennial SWW variability by almost an order of magnitude. The underestimated natural variability implies a substantial uncertainty in model projections of future SWW shifts.

Using Raspberry Pi to Teach Computing "Inside Out"

ERIC Educational Resources Information Center

Jaokar, Ajit

2013-01-01

This article discusses the evolution of computing education in preparing for the next wave of computing. With the proliferation of mobile devices, most agree that we are living in a "post-PC" world. Using the Raspberry Pi computer platform, based in the UK, as an example, the author discusses computing education in a world where the…

Vanishing Voices: The Extinction of the World's Languages.

ERIC Educational Resources Information Center

Nettle, Daniel; Romaine, Suzanne

This book holds that the evolution of the mind has given rise to great diversity of language and culture, each going along with a distinct adaptation to life specific ecosystems or geographical areas. Much like the wealth of plant and animal species is essential to biodiversity and ecological balance, diversity in the world's languages is vital to…

Intelligent Design and Earth History

NASA Astrophysics Data System (ADS)

Elders, W. A.

2001-05-01

Intelligent Design (ID), the idea that the Earth's biota was intelligently designed and created, is not a new species recently evolved by allopatric speciation at the fringes of the creationist gene pool. In spite of its new veneer of sophistication, ID is a variant of an already extant species of religious polemics. In the western world, arguments about causative relationships between the complexity of nature and the supernatural can be traced from the fifth century St. Augustine, to the eighteenth century David Hume and the nineteenth century William Paley. Along this descent tree some argued from the existence of supernatural agencies to the creation of nature with its complexities, while others argued from the complexities of nature to the existence of supernatural agencies. Today, Phillip Johnson promotes ID by attacking evolution rather than by presenting evidence for ID. He argues that the evidence for macroevolution is either absent, misinterpreted or fraudulent. His "Wedge Strategy" attempts to separate his "objective science" from the "philosophical mechanistic naturalism" which he posits is responsible for the survival of Darwinism. To make his appeal as wide as possible he tries not to offend anyone (except evolutionists) by deliberately avoiding discussion of biblical literalism or the age of the Earth. Although in 1859 Darwin admitted that the geological evidence was "the most obvious and gravest objection which can be urged against my theory", subsequently geological evidence has become one of the chief supports of his theory. However, the fossil record is now seen to be not simply one of slow gradual descent with modification. Rates of divergence and disappearance of organisms have varied enormously through time. Repeated mass extinctions indicate a strong element of contingency in evolution. Accepting the postulate of an intelligent designer also requires the postulate of an intelligent destroyer. Darwin hinted at this when he referred to, "The clumsy, wasteful works of nature as seen in the suffering caused by parasites and in the delight in cruelty shown by some predators when catching and playing with their prey". The positions of other contemporary proponents of ID are far from uniform. Some, while rejecting unguided evolution, appear to accept the concepts of common descent and an Earth 4.6 billion years old. However, within the ID movement there has been very little discussion of its implications for Earth history. For example, is it valid to ask, "Were the Himalayas intelligently designed?" Or should the question be, "Is the physics of plate tectonics intelligently designed?" As well as contingency in the history of life, there are strong elements of contingency in the history of the Earth, in the history of the solar system and in the history of the cosmos. Does ID matter? From a purely operational viewpoint, the rock record could equally well be interpreted in pattern-based investigations as being the product of either naturalistic processes, or as a sequence of intelligently designed events. For example, in correlating horizons between adjacent oil wells using micropaleontology, or in doing seismic stratigraphy, it makes little difference whether foraminifera or unconformities formed by natural or supernatural agencies. However, ID is an anathema for process-based research and its cultural implications are enormous. While we must be careful in our work to separate methodological naturalism from culturally bound philosophical naturalism, methodological naturalism has been an enormously successful approach in the advancement of knowledge. We have moved from the "demon-haunted" world to the world of the human genome. We must take ID seriously; it is a retrograde step.

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 ˜2,000 Ma ago, they first evolved slowly -- following the Cardinal Rule of Life -- until ˜1,000 Ma ago when sexual reproduction took over. This development markedly speeded the development of new species that could compete, and eventually dominate, in habitats previously owned by their non-sexual prokaryotic ancestors, as evidenced both in the fossil record and by molecular biology-based rRNA phylogenetic trees. The third innovation was cellular differentiation and multicelluarity. Although the "Cambrian Explosion" -- the great radiation of animal life during the Cambrian Period beginning ˜550 Ma ago -- is commonly viewed as reflecting this event, it seems more a continuum than a step-function change. Evolution speeded in the half-billion years between 1,000 Ma ago and the beginning of the Cambrian: phytoplankton gave rise to multicellular seaweeds by ˜850 Ma; and primitive protozoans, present as early as ˜950 Ma, had by ˜600 Ma given rise to soft-bodied multicelled animals. Soon thereafter, animals developed shelly protective armor -- marking the beginning of the Cambrian Period, and thus of the Phanerozoic Eon. The Phanerozoic history of life is familiar to all, from spore-producing to seed-producing to flowering plants, from animals without backbones to fish, land-dwelling vertebrates, then birds and mammals. Plants ("eatees") and animals ("eaters") co-evolved in sequence. Again, life followed the Cardinal Rule, changing little, then evolving rapidly, as new ecologic opportunities became available.

Thermal evolution of the western South Atlantic and the adjacent continent during Termination 1

NASA Astrophysics Data System (ADS)

Chiessi, C. M.; Mulitza, S.; Mollenhauer, G.; Silva, J. B.; Groeneveld, J.; Prange, M.

2014-12-01

During Termination 1, millennial-scale weakening events of the Atlantic meridional overturning circulation (AMOC) supposedly produced major changes in sea surface temperatures (SST) of the western South Atlantic, and in mean air temperatures (MAT) over southeastern South America. It was suggested, for instance, that the Brazil Current (BC) would strengthen (weaken) and the North Brazil Current (NBC) would weaken (strengthen) during slowdown (speed-up) events of the AMOC. This anti-phase pattern was claimed to be a necessary response to the decreased North Atlantic heat piracy during periods of weak AMOC. However, the thermal evolution of the western South Atlantic and the adjacent continent is largely unknown and a compelling record of the BC-NBC anti-phase behavior remains elusive. Here we address this issue, presenting high temporal resolution SST and MAT records from the BC and southeastern South America, respectively. We identify a warming in the western South Atlantic during Heinrich Stadial 1 (HS1), which is followed first by a drop and then by increasing temperatures during the Bølling-Allerød, in-phase with an existing NBC record. Additionally, a similar SST evolution is shown by a southernmost eastern South Atlantic record, suggesting a South Atlantic-wide pattern in SST evolution during most of Termination 1. Over southeastern South America, our MAT record shows a two-step increase during Termination 1, synchronous with atmospheric CO2 rise (i.e., during the second half of HS1 and during the Younger Dryas), and lagging abrupt SST changes by several thousand years. This delay corroborates the notion that the long duration of HS1 was fundamental to drive the Earth out of the last glacial.

Evaluating the Small-World-Ness of a Sampled Network: Functional Connectivity of Entorhinal-Hippocampal Circuitry

NASA Astrophysics Data System (ADS)

She, Qi; Chen, Guanrong; Chan, Rosa H. M.

2016-02-01

The amount of publicly accessible experimental data has gradually increased in recent years, which makes it possible to reconsider many longstanding questions in neuroscience. In this paper, an efficient framework is presented for reconstructing functional connectivity using experimental spike-train data. A modified generalized linear model (GLM) with L1-norm penalty was used to investigate 10 datasets. These datasets contain spike-train data collected from the entorhinal-hippocampal region in the brains of rats performing different tasks. The analysis shows that entorhinal-hippocampal network of well-trained rats demonstrated significant small-world features. It is found that the connectivity structure generated by distance-dependent models is responsible for the observed small-world features of the reconstructed networks. The models are utilized to simulate a subset of units recorded from a large biological neural network using multiple electrodes. Two metrics for quantifying the small-world-ness both suggest that the reconstructed network from the sampled nodes estimates a more prominent small-world-ness feature than that of the original unknown network when the number of recorded neurons is small. Finally, this study shows that it is feasible to adjust the estimated small-world-ness results based on the number of neurons recorded to provide a more accurate reference of the network property.

Evolution and palaeoenvironment of the Bauru Basin (Upper Cretaceous, Brazil)

NASA Astrophysics Data System (ADS)

Fernandes, Luiz Alberto; Magalhães Ribeiro, Claudia Maria

2015-08-01

The Bauru Basin was one of the great Cretaceous desert basins of the world, evolved in arid zone called Southern Hot Arid Belt. Its paleobiological record consists mainly of dinosaurs, crocodiles and turtles. The Bauru Basin is an extensive region of the South American continent that includes parts of the southeast and south of Brazil, covering an area of 370,000 km2. It is an interior continental basin that developed as a result of subsidence of the central-southern part of the South-American Platform during the Late Cretaceous (Coniacian-Maastrichtian). This sag basin is filled by a sandy siliciclastic sequence with a preserved maximum thickness of 480 m, deposited in semiarid to desert conditions. Its basement consists of volcanic rocks (mainly basalts) of the Lower Cretaceous (Hauterivian) Serra Geral basalt flows, of the Paraná-Etendeka Continental Flood Basalt Province. The sag basin was filled by an essentially siliciclastic psammitic sequence. In lithostratigraphic terms the sequence consists of the Caiuá and Bauru groups. The northern and northeastern edges of the basin provide a record of more proximal original deposits, such as associations of conglomeratic sand facies from alluvial fans, lakes, and intertwined distributary river systems. The progressive basin filling led to the burial of the basaltic substrate by extensive blanket sand sheets, associated with deposits of small dunes and small shallow lakes that retained mud (such as loess). Also in this intermediate context between the edges (more humid) and the interior (dry), wide sand sheet areas crossed by unconfined desert rivers (wadis) occurred. In the central axis of the elliptical basin a regional drainage system formed, flowing from northeast to southwest between the edges of the basin and the hot and dry inner periphery of the Caiuá desert (southwest). Life in the Bauru Basin flourished most in the areas with the greatest water availability, in which dinosaurs, crocodiles, turtles, fish, amphibians, molluscs, crustaceans, and charophyte algae lived. The fossil record mainly consists of transported bones and other skeletal fragments. In the northeastern and eastern marginal regions fossils are found in marginal alluvial fan deposits, broad plains of braided streams and ephemeral alkaline water lakes. In the basin interior the fossil record is related to deposits in sand sheets with braided streams, small dunes, and shallow lakes. In the great Caiuá inner desert a few smaller animals could survive (small reptiles and early mammals), sometimes leaving their footprints in dune foreset deposits. The aim of this article is to present and link the basin sedimentary evolution, palaeoecological features and palaeontological record.

Evidence for contemporary evolution during Darwin's lifetime.

PubMed

Hart, Adam G; Stafford, Richard; Smith, Angela L; Goodenough, Anne E

2010-02-09

Darwin's On the Origin of Species[1] introduced the world to the most fundamental concept in biological sciences - evolution. However, in the 150 years following publication of his seminal work, much has been made of the fact that Darwin was missing at least one crucial link in his chain of evidence - he had no evidence for contemporary evolution through natural selection. Indeed, as one commentator noted on the centenary of the publication of Origin, "Had Darwin observed industrial melanism he would have seen evolution occurring not in thousands of years but in thousands of days - well within his lifetime. He would have witnessed the consummation and confirmation of his life's work"[2].

The Bridges and Blockades to Evolutionary Convergence on the Road to Predicting Chikungunya Virus Evolution.

PubMed

Vignuzzi, Marco; Higgs, Stephen

2017-09-29

Chikungunya virus, first isolated in the 1950s, has since reemerged to cause several epidemics and millions of infections throughout the world. What was once blurred and confused with dengue virus in both diagnosis and name has since become one of the best-characterized arboviral diseases. In this review, we cover the history of this virus, its evolution into distinct genotypes and lineages, and, most notably, the convergent evolution observed in recent years. We highlight research that reveals to what extent convergent evolution, and its inherent predictability, may occur and what genetic or environmental factors may hinder it.

Empowering Students to Make Sense of an Information-Saturated World: The Evolution of "Information Searching and Analysis"

ERIC Educational Resources Information Center

Wittebols, James H.

2016-01-01

How well students conduct research online is an increasing concern for educators at all levels, especially higher education. This paper describes the evolution of a course that examines confirmation bias, information searching, and the political economy of information as keys to becoming more information and media literate. After a key assignment…

Pathways to Earth-like atmospheres. Extreme ultraviolet (EUV)-powered escape of hydrogen-rich protoatmospheres.

PubMed

Lammer, Helmut; Kislyakova, K G; Odert, P; Leitzinger, M; Schwarz, R; Pilat-Lohinger, E; Kulikov, Yu N; Khodachenko, M L; Güdel, M; Hanslmeier, M

2011-12-01

We discuss the evolution of the atmosphere of early Earth and of terrestrial exoplanets which may be capable of sustaining liquid water oceans and continents where life may originate. The formation age of a terrestrial planet, its mass and size, as well as the lifetime in the EUV-saturated early phase of its host star play a significant role in its atmosphere evolution. We show that planets even in orbits within the habitable zone of their host stars might not lose nebular- or catastrophically outgassed initial protoatmospheres completely and could end up as water worlds with CO2 and hydrogen- or oxygen-rich upper atmospheres. If an atmosphere of a terrestrial planet evolves to an N2-rich atmosphere too early in its lifetime, the atmosphere may be lost. We show that the initial conditions set up by the formation of a terrestrial planet and by the evolution of the host star's EUV and plasma environment are very important factors owing to which a planet may evolve to a habitable world. Finally we present a method for studying the discussed atmosphere evolution hypotheses by future UV transit observations of terrestrial exoplanets.

Genomics of bacteria and archaea: the emerging dynamic view of the prokaryotic world

PubMed Central

Koonin, Eugene V.; Wolf, Yuri I.

2008-01-01

The first bacterial genome was sequenced in 1995, and the first archaeal genome in 1996. Soon after these breakthroughs, an exponential rate of genome sequencing was established, with a doubling time of approximately 20 months for bacteria and approximately 34 months for archaea. Comparative analysis of the hundreds of sequenced bacterial and dozens of archaeal genomes leads to several generalizations on the principles of genome organization and evolution. A crucial finding that enables functional characterization of the sequenced genomes and evolutionary reconstruction is that the majority of archaeal and bacterial genes have conserved orthologs in other, often, distant organisms. However, comparative genomics also shows that horizontal gene transfer (HGT) is a dominant force of prokaryotic evolution, along with the loss of genetic material resulting in genome contraction. A crucial component of the prokaryotic world is the mobilome, the enormous collection of viruses, plasmids and other selfish elements, which are in constant exchange with more stable chromosomes and serve as HGT vehicles. Thus, the prokaryotic genome space is a tightly connected, although compartmentalized, network, a novel notion that undermines the ‘Tree of Life’ model of evolution and requires a new conceptual framework and tools for the study of prokaryotic evolution. PMID:18948295

The Other Side of Multidisciplinary Design Optimization: Accommodating a Multiobjective, Uncertain and Non-Deterministic World

NASA Technical Reports Server (NTRS)

Lewis, Kemper; Mistree, Farrokh

1998-01-01

The evolution of multidisciplinary design optimization (MDO) over the past several years has been one of rapid expansion and development. In this paper, the evolution of MDO as a field is investigated as well as the evolution of its individual linguistic components: multidisciplinary, design, and optimization. The theory and application of each component have indeed evolved on their own, but the true net gain for MDO is how these piecewise evolutions coalesce to form the basis for MDO, present and future. Originating in structural applications, MDO technology has also branched out into diverse fields and application arenas. The evolution and diversification of MDO as a discipline is explored but details are left to the references cited.

77 FR 22576 - Possible Revocation of Ocean Transportation Intermediary License No. 021899-Trans World Logistics...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-16

... FEDERAL MARITIME COMMISSION [Docket No. 12-04] Possible Revocation of Ocean Transportation Intermediary License No. 021899--Trans World Logistics Corporation; Order To Show Cause Trans World Logistics Corporation (Trans World Logistics) is an Indiana corporation, incorporated in October 2006. Records maintained by the Commission's Bureau of...

World energy resources

NASA Astrophysics Data System (ADS)

Clerici, A.; Alimonti, G.

2015-08-01

As energy is the main "fuel" for social and economic development and since energy-related activities have significant environmental impacts, it is important for decision-makers to have access to reliable and accurate data in an user-friendly format. The World Energy Council (WEC) has for decades been a pioneer in the field of energy resources and every three years publishes its flagship report Survey of Energy Resources. A commented analysis in the light of latest data summarized in such a report, World Energy Resources (WER) 2013, is presented together with the evolution of the world energy resources over the last twenty years.

Evolution of the central sulcus morphology in primates.

PubMed

Hopkins, William D; Meguerditchian, Adrien; Coulon, Olivier; Bogart, Stephanie; Mangin, Jean-François; Sherwood, Chet C; Grabowski, Mark W; Bennett, Allyson J; Pierre, Peter J; Fears, Scott; Woods, Roger; Hof, Patrick R; Vauclair, Jacques

2014-01-01

The central sulcus (CS) divides the pre- and postcentral gyri along the dorsal-ventral plane of which all motor and sensory functions are topographically organized. The motor-hand area of the precentral gyrus or KNOB has been described as the anatomical substrate of the hand in humans. Given the importance of the hand in primate evolution, here we examine the evolution of the motor-hand area by comparing the relative size and pattern of cortical folding of the CS surface area from magnetic resonance images in 131 primates, including Old World monkeys, apes and humans. We found that humans and great apes have a well-formed motor-hand area that can be seen in the variation in depth of the CS along the dorsal-ventral plane. We further found that great apes have relatively large CS surface areas compared to Old World monkeys. However, relative to great apes, humans have a small motor-hand area in terms of both adjusted and absolute surface areas. © 2014 S. Karger AG, Basel.

Angiography by Synchrotron Radiation

NASA Astrophysics Data System (ADS)

Rubenstein, E.; Brown, G. S.; Giacomini, J. C.; Gordon, H. J.; Hofstadter, R.; Kernoff, R. S.; Otis, J. N.; Thomlinson, W.; Thompson, A. C.; Zeman, H. D.

1987-01-01

Because coronary disease represents the principal health problem in the Western, industrialized world, and because of the risks and costs associated with conventional methods of visualizing the coronary arteries, an effort has been underway at the Stanford Synchrotron Radiation Laboratory to develop a less invasive coronary imaging procedure based on iodine K-edge dichromography. A pair of line images, recorded within a few milliseconds of each other, is taken with two monochromatic X-ray beams whose energy closely brackets the K-edge of iodine, 33.17 keV. The logarithmic subtraction of the images produced by these beams results in an image which greatly enhances signals arising from attenuation by iodine and almost totally suppresses signals arising from attenuation by soft tissue and bone. The high sensitivity to iodine allows the visualization of arterial structures after an intravenous injection of contrast agent and its subsequent 20-30 fold dilution. The experiments began in 1979, with initial studies done on phantoms and excised pig hearts. The first images of anesthetized dogs were taken in 1982. The results of experiments on dogs will be reviewed, showing the stepwise evolution of the imaging system, leading to the use of the system on human subjects in 1986. The images recorded on human subjects will be described and the remaining problems discussed.

Jump as Far as You Can [Problem Solvers: Problem

ERIC Educational Resources Information Center

Bofferding, Laura; Yigit, Melike

2013-01-01

The standing long jump was an Olympic event until 1912. In 1904, Ray Ewry set the world record for the longest standing long jump, which was about 11.5 feet, or 138 inches. Although the standing long jump is no longer an Olympic event, the Norwegians still include it in their National Competition, and Arne Tvervaag set a new world record at about…

The ancient history of the structure of ribonuclease P and the early origins of Archaea

PubMed Central

2010-01-01

Background Ribonuclease P is an ancient endonuclease that cleaves precursor tRNA and generally consists of a catalytic RNA subunit (RPR) and one or more proteins (RPPs). It represents an important macromolecular complex and model system that is universally distributed in life. Its putative origins have inspired fundamental hypotheses, including the proposal of an ancient RNA world. Results To study the evolution of this complex, we constructed rooted phylogenetic trees of RPR molecules and substructures and estimated RPP age using a cladistic method that embeds structure directly into phylogenetic analysis. The general approach was used previously to study the evolution of tRNA, SINE RNA and 5S rRNA, the origins of metabolism, and the evolution and complexity of the protein world, and revealed here remarkable evolutionary patterns. Trees of molecules uncovered the tripartite nature of life and the early origin of archaeal RPRs. Trees of substructures showed molecules originated in stem P12 and were accessorized with a catalytic P1-P4 core structure before the first substructure was lost in Archaea. This core currently interacts with RPPs and ancient segments of the tRNA molecule. Finally, a census of protein domain structure in hundreds of genomes established RPPs appeared after the rise of metabolic enzymes at the onset of the protein world. Conclusions The study provides a detailed account of the history and early diversification of a fundamental ribonucleoprotein and offers further evidence in support of the existence of a tripartite organismal world that originated by the segregation of archaeal lineages from an ancient community of primordial organisms. PMID:20334683

A Topical Trajectory on Survival: An Analysis of Link-Making in a Sequence of Lessons on Evolution

ERIC Educational Resources Information Center

Rocksén, Miranda; Olander, Clas

2017-01-01

This study explores the concept of link-making in relation to communicative strategies applied in the teaching and studying of biological evolution. The analysis focused on video recordings of 11 lessons on biological evolution conducted in a Swedish 9th grade class of students aged 15 years. It reveals how the teacher and students connected…

Lacustrine-fluvial interactions in Australia's Riverine Plains

NASA Astrophysics Data System (ADS)

Kemp, Justine; Pietsch, Timothy; Gontz, Allen; Olley, Jon

2017-06-01

Climatic forcing of fluvial systems has been a pre-occupation of geomorphological studies in Australia since the 1940s. In the Riverine Plain, southeastern Australia, the stable tectonic setting and absence of glaciation have combined to produce sediment loads that are amongst the lowest in the world. Surficial sediments and landforms exceed 140,000 yr in age, and geomorphological change recorded in the fluvial, fluvio-lacustrine and aeolian features have provided a well-studied record of Quaternary environmental change over the last glacial cycle. The region includes the Willandra Lakes, whose distinctive lunette lakes preserve a history of water-level variations and ecological change that is the cornerstone of Australian Quaternary chronostratigraphy. The lunette sediments also contain an ancient record of human occupation that includes the earliest human fossils yet found on the Australian continent. To date, the lake-level and palaeochannel records in the Lachlan-Willandra system have not been fully integrated, making it difficult to establish the regional significance of hydrological change. Here, we compare the Willandra Lakes environmental record with the morphology and location of fluvial systems in the lower Lachlan. An ancient channel belt of the Lachlan, Willandra Creek, acted as the main feeder channel to Willandra Lakes before channel avulsion caused the lakes to dry out in the late Pleistocene. Electromagnetic surveys, geomorphological and sedimentary evidence are used to reconstruct the evolution of the first new channel belt following the avulsion. Single grain optical dating of floodplain sediments indicates that sedimentation in the new Middle Billabong Palaeochannel had commenced before 18.4 ± 1.1 ka. A second avulsion shifted its upper reaches to the location of the present Lachlan River by 16.2 ± 0.9 ka. The timing of these events is consistent with palaeohydrological records reconstructed from Willandra Lakes and with the record of palaeochannels on the Lachlan River upstream. Willandra Lakes shows high inflows during the Last Glacial Maximum (∼22 ka), but their subsequent drying between 20.5 ka and 19 ka was caused by river avulsion rather than regional aridity. This case study highlights the benefits of combining fluvial with lacustrine archives to build complementary records of hydrological change in lowland riverine plains.

Speculations on the evolution of awareness.

PubMed

Graziano, Michael S A

2014-06-01

The "attention schema" theory provides one possible account of the biological basis of consciousness, tracing the evolution of awareness through steps from the advent of selective signal enhancement about half a billion years ago to the top-down control of attention, to an internal model of attention (which allows a brain, for the first time, to attribute to itself that it has a mind that is aware of something), to the ability to attribute awareness to other beings, and from there to the human attribution of a rich spirit world surrounding us. Humans have been known to attribute awareness to plants, rocks, rivers, empty space, and the universe as a whole. Deities, ghosts, souls--the spirit world swirling around us is arguably the exuberant attribution of awareness.

An examination of conceptual change in undergraduate biology majors while learning science concepts including biological evolution

NASA Astrophysics Data System (ADS)

McQuaide, Glenn G.

2006-12-01

Without adequate understanding of science, we cannot make responsible personal, regional, national, or global decisions about any aspect of life dealing with science. Better understanding how we learn about science can contribute to improving the quality of our educational experiences. Promoting pathways leading to life-long learning and deep understanding in our world should be a goal for all educators. This dissertation project was a phenomenological investigation into undergraduate understanding and acceptance of scientific theories, including biological evolution. Specifically, student descriptions of conceptual change while learning science theory were recorded and analyzed. These qualitative investigations were preceded by a survey that provided a means of selecting students who had a firmer understanding of science theory. Background information and survey data were collected in an undergraduate biology class at a small, Southern Baptist-affiliated liberal arts school located in south central Kentucky. Responses to questions on the MATE (Rutledge and Warden, 1999) instrument were used to screen students for interviews, which investigated the way by which students came to understand and accept scientific theories. This study identifies some ways by which individuals learn complex science theories, including biological evolution. Initial understanding and acceptance often occurs by the conceptual change method described by Posner et al. (1982). Three principle ways by which an individual may reach a level of understanding and acceptance of science theory were documented in this study. They were conceptual change through application of logic and reasoning; conceptual change through modification of religious views; and conceptual change through acceptance of authoritative knowledge. Development of a deeper, richer understanding and acceptance of complex, multi-faceted concepts such as biological evolution occurs in some individuals by means of conceptual enrichment. Conceptual enrichment occurs through addition of new knowledge, and then examining prior knowledge through the perspective of this new knowledge. In the field of science, enrichment reinforces complex concepts when multiple, convergent lines of supporting evidences point to the same rational scientific conclusion.

The Evolution of Darwinism.

ERIC Educational Resources Information Center

Stebbins, G. Ledyard; Ayala, Francisco J.

1985-01-01

Recent developments in molecular biology and new interpretations of the fossil record are gradually altering and adding to Charles Darwin's theory, which has been the standard view of the process of evolution for 40 years. Several of these developments and interpretations are identified and discussed. (JN)

Harnessing electronic healthcare data for wound care research: Standards for reporting observational registry data obtained directly from electronic health records.

PubMed

Fife, Caroline E; Eckert, Kristen A

2017-04-01

The United States Food and Drug Administration will consider the expansion of coverage indications for some drugs and devices based on real-world data. Real-world data accrual in patient registries has historically been via manual data entry from the medical chart at a time distant from patient care, which is fraught with systematic error. The efficient automated transmission of data directly from electronic health records is replacing this labor-intensive paradigm. However, real-world data collection is unfamiliar. The potential sources of bias arising from the source of data and data accrual, documentation, and aggregation have not been well defined. Furthermore, the technological aspects of data acquisition and transmission are less transparent. We explore opportunities for harnessing direct-from-electronic health record registry reporting and propose the ABCs of Registries (Analysis of Bias Criteria of Registries), which are an evaluation framework for publications to minimize potential bias of real-world data obtained directly from an electronic health record method. These standards are based on a point-of-care data documentation process using a common definitional framework and data dictionaries. By way of example, we describe a wound registry obtained directly from electronic health records. This qualified clinical data registry minimizes bias by ensuring complete and accurate point-of-care data capture, standardizes usual care linked to quality reporting, and prevents post-hoc vetting of outcomes. The resulting data are of high quality and integrity and can be used for comparative effectiveness research in wound care. In this way, the effort needed to succeed with the Quality Payment Program is leveraged to obtain the real-world data needed for comparative effectiveness research. © 2017 by the Wound Healing Society.

The Stratigraphic Incompleteness of Submarine Channels

NASA Astrophysics Data System (ADS)

Vendettuoli, D.; Clare, M. A.; Hughes Clarke, J. E.; Cartigny, M.; Vellinga, A. J.; Talling, P.; Hizzett, J. L.; Hage, S.; Waltham, D.; Hubbard, S. M.

2017-12-01

Turbidity currents transport prodigious quantities of sediment across the world's oceans through submarine channels. These flows damage strategically important seafloor infrastructure and their deposits host major oil and gas reservoirs. We therefore need to understand these flows, but their very powerful nature makes direct monitoring challenging. Most studies to date focus on the deposits that turbidity currents leave behind in the sedimentological record. However, deposits of individual flows are likely to be reworked by successive flows, but it is unclear as to what extent. How complete is the stratigraphy of these deposits? What percentage of flow deposits are preserved in the rock record? Are some events better preserved than others, and if so, why? We address these questions by re-analysing the most detailed time-lapse mapping yet of a turbidity current system. This field dataset comes from the fjord-head Squamish Delta in British Columbia, Canada where Hughes Clarke (2016) collected 93 near-daily repeat surveys in 2011. These surveys revealed the seafloor response to more than 100 turbidity currents. Here we use temporal changes in seabed elevation to understand patterns of deposition and erosion. We calculate the total thickness of sediment deposited at each location, and document the percentage of sediment that is preserved (i.e. stratigraphic completeness) at multiple time-steps over the surveyed period. The average stratigraphic completeness across the delta near submarine channels is <1%, but this is highly spatially variable. Some levees record up to 40% completeness. The low value is largely due to upstream migrating bedforms that constantly rework previously emplaced sediments. Surprisingly, even at the terminal lobes, stratigraphic completeness is typically <5%. These results provide new insights into the evolution of submarine channels and why their deposits produce a highly incomplete record of submarine flows.

Play and Adversity: How the Playful Mammalian Brain Withstands Threats and Anxieties

ERIC Educational Resources Information Center

Siviy, Stephen M.

2010-01-01

Most mammals play, but they do so in a dangerous world. The dynamic relationship between the stresses created by their world and the activity of play helps to explain the evolution of play in mammals, as the author demonstrates in evidence garnered from experiments that introduce elements of fear to rats at play. The author describes the resulting…

Actually the World Is Quite Bumpy: Using Friedman in the International Business Law Classroom

ERIC Educational Resources Information Center

Dhooge, Lucien J.

2006-01-01

In "The World Is Flat: A Brief History of the Twenty-First Century," Pulitzer Prize recipient and New York Times foreign affairs correspondent Thomas L. Friedman examines the evolution of globalization in the six years since the publication of his highly acclaimed introduction to the topic in "The Lexus and the Olive Tree: Understanding…

From Authoritative Discourse to Internally Persuasive Discourse: Discursive Evolution in Teaching and Learning the Language of Science

ERIC Educational Resources Information Center

Hsu, Pei-Ling; Roth, Wolff-Michael

2014-01-01

Learning science interpreted in existing theoretical frameworks often means that students are assimilated, accommodated or enculturated from the entity of the vernacular world to the entity of the scientific world. However, there are some unsolved questions as to how students can best learn purely a new language or new knowledge of science. The…

Using response evaluation criteria in solid tumors in real-world evidence cancer research.

PubMed

Feinberg, Bruce A; Bharmal, Murtuza; Klink, Andrew J; Nabhan, Chadi; Phatak, Hemant

2018-05-31

Real-world evidence of charted treatment responses to cancer drug therapy was compared with medical record derived radiographic measurements of target lesions per Response Evaluation Criteria in Solid Tumors (RECIST). 15 physicians treating 59 metastatic Merkel cell cancer (mMCC) patients contributed patient-level data. A comparison of medical record reported best response with radiographic measurements per RECIST of pre- and post-treatment target lesions. RECIST response rates were significantly lower compared with medical record reported with a concordance of 43.2% (95% CI: 28.0-58.4%). Subjective assessment of tumor response collected via traditional chart abstraction may overestimate benefit and limit the potential role of real-world evidence in value-based care research. The use of target lesion measurements presents an attractive alternative that better aligns with trial results.

The Microcosm within: An interview with William B. Miller, Jr., on the Extended Hologenome theory of evolution.

PubMed

Hunt, Tam

2015-01-01

There is a singular unifying reality underlying every biologic interaction on our planet. In immunology, that which does not kill you makes you different. -William B. Miller, Jr. We are experiencing a revolution in our understanding of inner space on a par with our exponentially increasing understanding of outer space. In biology, we are learning that the genetic and epigenetic complexity within organisms is far deeper than suspected. This is a key theme in William B. Miller Jr.'s book, The Microcosm Within: Evolution and Extinction in the Hologenome. We are learning also that a focus on the human genome alone is misleading when it comes to who we really are as biological entities, and in terms of how we and other creatures have evolved. Rather than being defined by the human genome alone, we are instead defined by the "hologenome," the sum of the human genome and the far larger genetic endowment of the microbiome and symbiotic communities that reside within and around us. Miller is a medical doctor previously in private practice in Pennsylvania and Phoenix, Arizona. This book is his first foray into evolutionary theory. His book could have been titled "The Origin of Variation" because this is his primary focus. He accepts that natural selection plays a role in evolution, but he demotes this mechanism to a less important role than the Modern Synthesis suggests. His main gripe, however, concerns random variation. He argues that random variation is unable to explain the origin and evolution of biological forms that we see in the world around us and in the historical record. Miller suggests that, rather than random variation as the engine of novelty, there is a creative impulse at the heart of cellular life, and even at the level of the genetic aggregate, that generates novelty on a regular basis. I probe this assertion in the interview below. He also highlights the strong role of "exogenous genetic assault" in variation and in his immunological model of evolution.

Shining evolutionary light on human sleep and sleep disorders

PubMed Central

Nunn, Charles L.; Samson, David R.; Krystal, Andrew D.

2016-01-01

Sleep is essential to cognitive function and health in humans, yet the ultimate reasons for sleep—i.e. ‘why’ sleep evolved—remain mysterious. We integrate findings from human sleep studies, the ethnographic record, and the ecology and evolution of mammalian sleep to better understand sleep along the human lineage and in the modern world. Compared to other primates, sleep in great apes has undergone substantial evolutionary change, with all great apes building a sleeping platform or ‘nest’. Further evolutionary change characterizes human sleep, with humans having the shortest sleep duration, yet the highest proportion of rapid eye movement sleep among primates. These changes likely reflect that our ancestors experienced fitness benefits from being active for a greater portion of the 24-h cycle than other primates, potentially related to advantages arising from learning, socializing and defending against predators and hostile conspecifics. Perspectives from evolutionary medicine have implications for understanding sleep disorders; we consider these perspectives in the context of insomnia, narcolepsy, seasonal affective disorder, circadian rhythm disorders and sleep apnea. We also identify how human sleep today differs from sleep through most of human evolution, and the implications of these changes for global health and health disparities. More generally, our review highlights the importance of phylogenetic comparisons in understanding human health, including well-known links between sleep, cognitive performance and health in humans. PMID:27470330

Connecting the surface to the deep: Flat-slab subduction dynamics and the evolution of western Amazonia

NASA Astrophysics Data System (ADS)

Eakin, C. M.

2017-12-01

Plate tectonics is primarily driven by the subduction of cold dense oceanic slabs. It has yet to be fully understood however how variations in slab morphology and buoyancy influence the surrounding mantle dynamics, and what difference if any is seen at the surface. An excellent natural laboratory to answer such questions is found along the Andean margin where the world's largest flat slab is presently subducting beneath much of Peru. Following the deployment of broadband seismic arrays across the region, mantle flow both beneath and above the flat-slab is investigated using targeted shear-wave splitting techniques that detect seismic anisotropy and the pattern of mantle deformation. The along strike change in slab dip angle and buoyancy content is found to exert a strong control over the surrounding mantle flow field. Modeling of the induced mantle flow, and the dynamic topography at the surface that results, predicts a wave of dynamic subsidence that propagates away from the trench as the flat slab develops. This is found to correlate well with the record of widespread sediment deposition across western Amazonia during the Miocene. A combination of uplift, flexure and dynamic topography during slab flattening is proposed to explain the overall landscape evolution of the region and the subsequent configuration of the transcontinental Amazon drainage system we see today.

A stacked Late Quaternary fluvio-periglacial sequence from the Axe valley, southern England with implications for landscape evolution and Palaeolithic archaeology

NASA Astrophysics Data System (ADS)

Brown, A. G.; Basell, L. S.; Toms, P. S.

2015-05-01

The current model of mid-latitude late Quaternary terrace sequences, is that they are uplift-driven but climatically controlled terrace staircases, relating to both regional-scale crustal and tectonic factors, and palaeohydrological variations forced by quasi-cyclic climatic conditions in the 100 K world (post Mid Pleistocene Transition). This model appears to hold for the majority of the river valleys draining into the English Channel which exhibit 8-15 terrace levels over approximately 60-100 m of altitudinal elevation. However, one valley, the Axe, has only one major morphological terrace and has long-been regarded as anomalous. This paper uses both conventional and novel stratigraphical methods (digital granulometry and terrestrial laser scanning) to show that this terrace is a stacked sedimentary sequence of 20-30 m thickness with a quasi-continuous (i.e. with hiatuses) pulsed, record of fluvial and periglacial sedimentation over at least the last 300-400 K yrs as determined principally by OSL dating of the upper two thirds of the sequence. Since uplift has been regional, there is no evidence of anomalous neotectonics, and climatic history must be comparable to the adjacent catchments (both of which have staircase sequences) a catchment-specific mechanism is required. The Axe is the only valley in North West Europe incised entirely into the near-horizontally bedded chert (crypto-crystalline quartz) and sand-rich Lower Cretaceous rocks creating a buried valley. Mapping of the valley slopes has identified many large landslide scars associated with past and present springs. It is proposed that these are thaw-slump scars and represent large hill-slope failures caused by Vauclausian water pressures and hydraulic fracturing of the chert during rapid permafrost melting. A simple 1D model of this thermokarstic process is used to explore this mechanism, and it is proposed that the resultant anomalously high input of chert and sand into the valley during terminations caused pulsed aggradation until the last termination. It is also proposed that interglacial and interstadial incision may have been prevented by the over-sized and interlocking nature of the sub-angular chert clasts until the Lateglacial when confinement of the river overcame this immobility threshold. One result of this hydrogeologically mediated valley evolution was to provide a sequence of proximal Palaeolithic archaeology over two MIS cycles. This study demonstrates that uplift tectonics and climate alone do not fully determine Quaternary valley evolution and that lithological and hydrogeological conditions are a fundamental cause of variation in terrestrial Quaternary records and landform evolution.

Distributed Emulation in Support of Large Networks

DTIC Science & Technology

2016-06-01

Provider LTE Long Term Evolution MB Megabyte MIPS Microprocessor without Interlocked Pipeline Stages MRT Multi-Threaded Routing Toolkit NPS Naval...environment, modifications to a network, protocol, or model can be executed – and the effects measured – without affecting real-world users or services...produce their results when analyzing performance of Long Term Evolution ( LTE ) gateways [3]. Many research scenarios allow problems to be represented

Combining Small-Vertebrate, Marine and Stable-Isotope Data to Reconstruct Past Environments

PubMed Central

Rofes, Juan; Garcia-Ibaibarriaga, Naroa; Aguirre, Mikel; Martínez-García, Blanca; Ortega, Luis; Zuluaga, María Cruz; Bailon, Salvador; Alonso-Olazabal, Ainhoa; Castaños, Jone; Murelaga, Xabier

2015-01-01

Three very different records are combined here to reconstruct the evolution of environments in the Cantabrian Region during the Upper Pleistocene, covering ~35.000 years. Two of these records come from Antoliñako Koba (Bizkaia, Spain), an exceptional prehistoric deposit comprising 9 chrono-cultural units (Aurignacian to Epipaleolithic). The palaeoecological signal of small-vertebrate communities and red deer stable-isotope data (δ13C and δ15N) from this mainland site are contrasted to marine microfaunal evidence (planktonic and benthic foraminifers, ostracods and δ18O data) gathered at the southern Bay of Biscay. Many radiocarbon dates for the Antoliña’s sequence, made it possible to compare the different proxies among them and with other well-known North-Atlantic records. Cooling and warming events regionally recorded, mostly coincide with the climatic evolution of the Upper Pleistocene in the north hemisphere. PMID:26391668

Infectious diseases in the 21st century: old challenges and new opportunities.

PubMed

Waldvogel, Francis A

2004-01-01

Infectious diseases are the confrontation of two worlds, the microbial world and the world of human physiology. Although these two worlds are as a whole governed by the same laws of nature, they show substantial differences: the microbiological world is 1000 times older, and was initiated by the development of the archaea, the 'living organisms of the extreme': its biomass and its diversity are immense - two to three billion species or 60% of the total biomass of the planet. The number of pathogens that adapted to man, however, is extremely limited - barely 1000. Thus, over billions of years, an evolution of the microbial world took place from 'early life', characterized by chemosynthesis, to the 'modern pathogens', and entailed a dramatic 'concentration' of life conditions and an adaptation towards a narrow range of requirements - those allowing survival in the human body. Within the last two centuries, these two slowly evolving systems, microbial life and human life, were profoundly modified in an unprecedented manner by a third player, human civilization, with its global impact on the environment through physical, chemical, societal, and climatic determinants. An appreciation of the evolution of infectious diseases in the 21st century and of the development of new diagnostic and therapeutic strategies therefore requires a full understanding of these three domains: human physiology, microbiology, and the environment. This review will put major emphasis on the environmental role of civilization on infectious diseases before considering new opportunities to combat them through novel and creative solutions.

On World Religion Adherence Distribution Evolution

NASA Astrophysics Data System (ADS)

Ausloos, Marcel; Petroni, Filippo

Religious adherence can be considered as a degree of freedom, in a statistical physics sense, for a human agent belonging to a population. The distribution, performance and life time of religions can thus be studied having in mind heterogeneous interacting agent modeling. We present a comprehensive analysis of 58 so-called religions (to be better defined in the main text) as measured through their number of adherents evolutions, between 1900 and 2000, - data taken from the World Christian Trends (Barrett and Johnson, "World Christian Trends AD 30 - AD 2200: Interpreting the Annual Christian Megacensus", William Carey Library, 2001): 40 are considered to be "presently growing" cases, including 11 turn overs in the twentieth century; 18 are "presently decaying", among which 12 are found to have had a recent maximum, in the nineteenth or the twentieth century. The Avrami-Kolmogorov differential equation which usually describes solid state transformations, like crystal growth, is used in each case in order to obtain the preferential attachment parameter introduced previously (Europhys Lett 77:38002, 2007). It is not often found close to unity, though often corresponding to a smooth evolution. However large values suggest the occurrence of extreme cases which we conjecture are controlled by so-called external fields. A few cases indicate the likeliness of a detachment process. We discuss a few growing and decaying religions, and illustrate various fits. Some cases seem to indicate the lack of reliability of the data, but others some marked departure from Avrami law. Whence the Avrami evolution equation might be surely improved, in particular, and somewhat obviously, for the decaying religion cases. We point out two major difficulties in such an analysis: (1) the "precise" original time of apparition of a religion, (2) the time at which there is a maximum number of adherents, both information being necessary for integrating reliably any evolution equation.

The RNA World: Life Before DNA and Protein

NASA Technical Reports Server (NTRS)

Joyce, Gerald F.

1993-01-01

All of the life that is known, all organisms that exist on Earth today or are known to have existed on Earth in the past, are of the same life form: a life form based on DNA and protein. It does not necessarily have to be that way. Why not have two competing life forms on this planet? Why not have biology as we know it and some other biology that occupies its own distinct niche? Yet that is not how evolution has played out. From microbes living on the surface of antarctic ice to tube worms lying near the deep-sea hydrothermal vents, all known organisms on this planet are of the same biology. Looking at the single known biology on Earth, it is clear that this biology could not have simply sprung forth from the primordial soup. The biological system that is the basis for all known. life is far too complicated to have arisen spontaneously. This brings us to the notion that something else something simpler, must have preceded life based on DNA and protein. One suggestion that has gained considerable acceptance over the past decade is that DNA and protein-based life was preceded by RNA-based life in a period referred to as the 'RNA world'. Even an RNA-based life form would have been fairly complicated - not as complicated as our own DNA- and protein-based life form - but far too complicated, according to prevailing scientific thinking, to have arisen spontaneously from the primordial soup. Thus, it has been argued that something else must have preceded RNA-based life, or even that there was a succession of life forms leading from the primordial soup to RNA-based life. The experimental evidence to support this conjecture is not strong because, after all, the origin of life was a historical event that left no direct physical record. However, based on indirect evidence in both the geological record and the phylogenetic record of evolutionary history on earth, it is possible to reconstruct a rough picture of what life was like before DNA and protein.

Modeling of Women's 100-M Dash World Record: Wind-Aided or Not?

ERIC Educational Resources Information Center

Hazelrigg, Conner; Waibel, Bryson; Baker, Blane

2015-01-01

On July 16, 1988, Florence Griffith Joyner (FGJ) shattered the women's 100-m dash world record (WR) with a time of 10.49 s, breaking the previous mark by an astonishing 0.27 s. By all accounts FGJ dominated the race that day, securing her place as the premiere female sprinter of that era, and possibly all time. In the aftermath of such an…

Remote Sensing for Risk Assessment of Via Iulia Augusta in Albenga

NASA Astrophysics Data System (ADS)

Van Meerbeek, Lore; Barazzetti, Luigi

2017-04-01

Today, the field of cultural heritage faces many challenges: cultural heritage is always at risk and heritage recording can be time-consuming and result in low accuracy. These challenges were visible during the risk assessment of Via Iulia Augusta in Albenga (Liguria, Italy). The traces of Via Iulia Augusta, a former Roman Road, connect several cultural heritage resources in Albenga's landscape. The cultural significance of these heritage sites is at risk. Threats and disturbances related to humans, development, site management, nature and climate were observed during the onsite visit. These impacts can be sudden or part of a very slow process, resulting in reduced values on cultural, social, economic and ecological level. Nature and climate (change) in Albenga impact the heritage sites the most. Water-related problems such as flooding and surface runoff have always been present in Albenga, but the amount seems to increase year by year due to global warming and is supposed to become even more critical in the future. The first step towards a risk management plan is recording and documenting these cultural heritage sites at risk. Heritage recording provides valuable documentation of the primary source, the cultural heritage itself. The produced ground plans, elevations, sections and details are the most important primary information source for every research. However, the size and complexity of the cultural heritage, the required accuracy and the time span could have a negative influence on heritage recording and documentation. This paper demonstrates the potential of remote sensing techniques for cultural heritage at risk. On site surveys with GPS, Unmanned Aerial Vehicle and photo camera gave reliable information of the heritage resources and its state of conservation. WorldView-2 Satellite images, extracted at different time periods, gave insight in the evolution of the cultural landscape in Albenga. This information resulted in several conclusions. First of all, the used remote sensing tools proved to be time-efficient and effective since they are able to gather a large amount of data with a high accuracy on a relative short time. Secondly, they are non-destructive techniques and fit in this sense within the concepts of preventive conservation. They do not decrease heritage's cultural significance. Third, aerial orthophotos, created with the use of photogrammetry, give insight on the state of conservation of heritage sites. They give the ability to monitor the risks and the threats of the site, as part of a risk management method. Finally, multi-spectral satellite images extracted at different time periods, made it possible to carry out studies on land use evolution. The results revealed that Albenga is subjected by urban sprawl. This uncontrolled development is threatening the intrinsic values of the cultural landscape and the cultural heritage sites along the Via Iulia Augusta. In conclusion, remote sensing tools proved to be time-efficient, accurate, non-destructive, recording and monitoring tools which provide information on the state of conservation of heritage sites and the evolution of cultural landscapes. This information is extremely useful when managing threats and disturbances at cultural heritage sites.

Molecular clocks and the early evolution of metazoan nervous systems.

PubMed

Wray, Gregory A

2015-12-19

The timing of early animal evolution remains poorly resolved, yet remains critical for understanding nervous system evolution. Methods for estimating divergence times from sequence data have improved considerably, providing a more refined understanding of key divergences. The best molecular estimates point to the origin of metazoans and bilaterians tens to hundreds of millions of years earlier than their first appearances in the fossil record. Both the molecular and fossil records are compatible, however, with the possibility of tiny, unskeletonized, low energy budget animals during the Proterozoic that had planktonic, benthic, or meiofaunal lifestyles. Such animals would likely have had relatively simple nervous systems equipped primarily to detect food, avoid inhospitable environments and locate mates. The appearance of the first macropredators during the Cambrian would have changed the selective landscape dramatically, likely driving the evolution of complex sense organs, sophisticated sensory processing systems, and diverse effector systems involved in capturing prey and avoiding predation. © 2015 The Author(s).

Looking through the Zircon Kaleidoscope: Durations, Rates, and Fluxes in Silicic Magmatic System

NASA Astrophysics Data System (ADS)

Schaltegger, U.; Wotzlaw, J. F.

2014-12-01

The crystallization rate of zircon in a cooling magma depends on the cooling rate through the saturation interval in addition to compositional and kinetic factors. Repeated influx of hot magma over 10-20 ka leads to short-amplitude temperature oscillations, which are recorded by resorption/crystallization cycles of zircon. Plotting the number of dated zircons versus their high-precision U-Pb date results in curves that qualitatively relate to the evolution of magma temperature over time [1], [2]. The trace elemental, O and Hf isotopic composition of zircon gives indications about the degree of magma homogenization and thermal evolution. Zircons from systems with small volumes and magma fluxes record non-systematic chemical and Hf isotopic heterogeneity, suggesting crystallization in non-homogenized ephemeral magma batches. Such systems typically lead to small, mid-upper crustal plutons [3]. Zircons from large-volume crystal-poor rhyolites record initial heterogeneities and rapid amalgamation of smaller magma batches over 10 ka [4], while zircons from monotonous intermediates record magma evolution over several 100 ka with coherent fractionation trends suggesting homogenization and a coherent thermal evolution [2]. In both cases, volumes and flux rates were sufficient to produce large volumes of eruptible magma on very contrasting time scales. Zircon is therefore recording cyclic crystallization-rejuvenation processes during temperature fluctuations in intermediate to upper crustal magma reservoirs but may not relate to the physical pluton emplacement or eruption. We can quantify volumes, rates of magma influx, rates of cooling and crystallization, and the degree of convective homogenization from zircon data, and infer reservoir assembly and eruption trigger mechanisms. These parameters largely control the evolution of long-lived, low-flux silicic magmatic system typical for mid-to-upper crustal plutons, monotonous intermediates are characterized by intermediate durations and fluxes while short-lived, high-flux systems preferentially produce crystal-poor rhyolites. References: [1] Caricchi et al. (2014) Nature 511, 457-461; [2] Wotzlaw et al. (2013) Geology 41, 867-870; [3] Broderick (2013) PhD thesis, Univ. of Geneva; [3] Wotzlaw et al. (2014) Geology, doi:10.1130/G35979.1

Compositional Variations of Paleogene and Neogene Tephra From the Northern Izu-Bonin-Mariana Arc

NASA Astrophysics Data System (ADS)

Tepley, F. J., III; Barth, A. P.; Brandl, P. A.; Hickey-Vargas, R.; Jiang, F.; Kanayama, K.; Kusano, Y.; Li, H.; Marsaglia, K. M.; McCarthy, A.; Meffre, S.; Savov, I. P.; Yogodzinski, G. M.

2014-12-01

A primary objective of IODP Expedition 351 was to evaluate arc initiation processes of the Izu-Bonin-Mariana (IBM) volcanic arc and its compositional evolution through time. To this end, a single thick section of sediment overlying oceanic crust was cored in the Amami Sankaku Basin where a complete sediment record of arc inception and evolution is preserved. This sediment record includes ash and pyroclasts, deposited in fore-arc, arc, and back-arc settings, likely associated with both the ~49-25 Ma emergent IBM volcanic arc and the evolving Ryukyu-Kyushu volcanic arc. Our goal was to assess the major element evolution of the nascent and evolving IBM system using the temporally constrained record of the early and developing system. In all, more than 100 ash and tuff layers, and pyroclastic fragments were selected from temporally resolved portions of the core, and from representative fractions of the overall core ("core catcher"). The samples were prepared to determine major and minor element compositions via electron microprobe analyses. This ash and pyroclast record will allow us to 1) resolve the Paleogene evolutionary history of the northern IBM arc in greater detail; 2) determine compositional variations of this portion of the IBM arc through time; 3) compare the acquired data to an extensive whole rock and tephra dataset from other segments of the IBM arc; 4) test hypotheses of northern IBM arc evolution and the involvement of different source reservoirs; and 5) mark important stratigraphic markers associated with the Neogene volcanic history of the adjacent evolving Ryukyu-Kyushu arc.

Phylogenetic modeling of lateral gene transfer reconstructs the pattern and relative timing of speciations

PubMed Central

Szöllősi, Gergely J.; Boussau, Bastien; Abby, Sophie S.; Tannier, Eric; Daubin, Vincent

2012-01-01

The timing of the evolution of microbial life has largely remained elusive due to the scarcity of prokaryotic fossil record and the confounding effects of the exchange of genes among possibly distant species. The history of gene transfer events, however, is not a series of individual oddities; it records which lineages were concurrent and thus provides information on the timing of species diversification. Here, we use a probabilistic model of genome evolution that accounts for differences between gene phylogenies and the species tree as series of duplication, transfer, and loss events to reconstruct chronologically ordered species phylogenies. Using simulations we show that we can robustly recover accurate chronologically ordered species phylogenies in the presence of gene tree reconstruction errors and realistic rates of duplication, transfer, and loss. Using genomic data we demonstrate that we can infer rooted species phylogenies using homologous gene families from complete genomes of 10 bacterial and archaeal groups. Focusing on cyanobacteria, distinguished among prokaryotes by a relative abundance of fossils, we infer the maximum likelihood chronologically ordered species phylogeny based on 36 genomes with 8,332 homologous gene families. We find the order of speciation events to be in full agreement with the fossil record and the inferred phylogeny of cyanobacteria to be consistent with the phylogeny recovered from established phylogenomics methods. Our results demonstrate that lateral gene transfers, detected by probabilistic models of genome evolution, can be used as a source of information on the timing of evolution, providing a valuable complement to the limited prokaryotic fossil record. PMID:23043116

The Moon as a recorder of organic evolution in the early solar system: a lunar regolith analog study.

PubMed

Matthewman, Richard; Court, Richard W; Crawford, Ian A; Jones, Adrian P; Joy, Katherine H; Sephton, Mark A

2015-02-01

The organic record of Earth older than ∼3.8 Ga has been effectively erased. Some insight is provided to us by meteorites as well as remote and direct observations of asteroids and comets left over from the formation of the Solar System. These primitive objects provide a record of early chemical evolution and a sample of material that has been delivered to Earth's surface throughout the past 4.5 billion years. Yet an effective chronicle of organic evolution on all Solar System objects, including that on planetary surfaces, is more difficult to find. Fortunately, early Earth would not have been the only recipient of organic matter-containing objects in the early Solar System. For example, a recently proposed model suggests the possibility that volatiles, including organic material, remain archived in buried paleoregolith deposits intercalated with lava flows on the Moon. Where asteroids and comets allow the study of processes before planet formation, the lunar record could extend that chronicle to early biological evolution on the planets. In this study, we use selected free and polymeric organic materials to assess the hypothesis that organic matter can survive the effects of heating in the lunar regolith by overlying lava flows. Results indicate that the presence of lunar regolith simulant appears to promote polymerization and, therefore, preservation of organic matter. Once polymerized, the mineral-hosted newly formed organic network is relatively protected from further thermal degradation. Our findings reveal the thermal conditions under which preservation of organic matter on the Moon is viable.

Planets and Life

NASA Astrophysics Data System (ADS)

Sullivan, Woodruff T., III; Baross, John

2007-09-01

Foreword; Preface; Contributors; Prologue; Part I. History: 1. History of astrobiological ideas W. T. Sullivan and D. Carney; 2. From exobiology to astrobiology S. J. Dick; Part II. The Physical Stage: 3. Formation of Earth-like habitable planets D. E. Brownlee and M. Kress; 4. Planetary atmospheres and life D. Catling and J. F. Kasting; Part III. The Origin of Life on Earth: 5. Does 'life' have a definition? C.E. Cleland and C. F. Chyba; 6. Origin of life: crucial issues R. Shapiro; 7. Origin of proteins and nucleic acids A. Ricardo and S. A. Benner; 8. The roots of metabolism G.D. Cody and J. H. Scott; 9. Origin of cellular life D. W. Deamer; Part IV. Life on Earth: 10. Evolution: a defining feature of life J. A. Baross; 11. Evolution of metabolism and early microbial communities J. A. Leigh, D. A. Stahl and J. T. Staley; 12. The earliest records of life on Earth R. Buick; 13. The origin and diversification of eukaryotes M. L. Sogin, D. J. Patterson and A. McArthur; 14. Limits of carbon life on Earth and elsewhere J. A. Baross, J. Huber and M. Schrenk; 15. Life in ice J. W. Deming and H. Eicken; 16. The evolution and diversification of life S. Awramik and K. J. McNamara; 17. Mass extinctions P. D. Ward; Part V. Potentially Habitable Worlds: 18. Mars B. M. Jakosky, F. Westall and A. Brack; 19. Europa C. F. Chyba and C. B. Phillips; 20. Titan J. I. Lunine and B. Rizk; 21. Extrasolar planets P. Butler; Part VI. Searching for Extraterrestrial Life: 22. How to search for life on other worlds C. P. McKay; 23. Instruments and strategies for detecting extraterrestrial life P. G. Conrad; 24. Societial and ethical concerns M. S. Race; 25. Planetary protection J. D. Rummel; 26. Searching for extraterrestrial intelligence J. C. Tarter; 27. Alien biochemistries P. D. Ward and S. A. Benner; Part VII. Future of the Field: 28. Disciplinary and educational opportunities L. Wells, J. Armstrong and J. Huber; Epilogue C. F. Chyba; Appendixes: A. Units and usages; B. Planetary properties; C. The geological time scale S. Awramik and K. J. McNamara; D. Astrobiological destinations on planet Earth J. Harnmeijer; E. Micro*scope web tool D. J. Patterson and M. L. Sogin; Index.

The emergence and evolution of life in a "fatty acid world" based on quantum mechanics.

PubMed

Tamulis, Arvydas; Grigalavicius, Mantas

2011-02-01

Quantum mechanical based electron correlation interactions among molecules are the source of the weak hydrogen and Van der Waals bonds that are critical to the self-assembly of artificial fatty acid micelles. Life on Earth or elsewhere could have emerged in the form of self-reproducing photoactive fatty acid micelles, which gradually evolved into nucleotide-containing micelles due to the enhanced ability of nucleotide-coupled sensitizer molecules to absorb visible light. Comparison of the calculated absorption spectra of micelles with and without nucleotides confirmed this idea and supports the idea of the emergence and evolution of nucleotides in minimal cells of a so-called Fatty Acid World. Furthermore, the nucleotide-caused wavelength shift and broadening of the absorption pattern potentially gives these molecules an additional valuable role, other than a purely genetic one in the early stages of the development of life. From the information theory point of view, the nucleotide sequences in such micelles carry positional information providing better electron transport along the nucleotide-sensitizer chain and, in addition, providing complimentary copies of that information for the next generation. Nucleotide sequences, which in the first period of evolution of fatty acid molecules were useful just for better absorbance of the light in the longer wavelength region, later in the PNA or RNA World, took on the role of genetic information storage.

Constraints and entropy in a model of network evolution

NASA Astrophysics Data System (ADS)

Tee, Philip; Wakeman, Ian; Parisis, George; Dawes, Jonathan; Kiss, István Z.

2017-11-01

Barabási-Albert's "Scale Free" model is the starting point for much of the accepted theory of the evolution of real world communication networks. Careful comparison of the theory with a wide range of real world networks, however, indicates that the model is in some cases, only a rough approximation to the dynamical evolution of real networks. In particular, the exponent γ of the power law distribution of degree is predicted by the model to be exactly 3, whereas in a number of real world networks it has values between 1.2 and 2.9. In addition, the degree distributions of real networks exhibit cut offs at high node degree, which indicates the existence of maximal node degrees for these networks. In this paper we propose a simple extension to the "Scale Free" model, which offers better agreement with the experimental data. This improvement is satisfying, but the model still does not explain why the attachment probabilities should favor high degree nodes, or indeed how constraints arrive in non-physical networks. Using recent advances in the analysis of the entropy of graphs at the node level we propose a first principles derivation for the "Scale Free" and "constraints" model from thermodynamic principles, and demonstrate that both preferential attachment and constraints could arise as a natural consequence of the second law of thermodynamics.

Bergmann's Rule, Adaptation, and Thermoregulation in Arctic Animals: Conflicting Perspectives from Physiology, Evolutionary Biology, and Physical Anthropology After World War II.

PubMed

Hagen, Joel B

2017-05-01

Bergmann's rule and Allen's rule played important roles in mid-twentieth century discussions of adaptation, variation, and geographical distribution. Although inherited from the nineteenth-century natural history tradition these rules gained significance during the consolidation of the modern synthesis as evolutionary theorists focused attention on populations as units of evolution. For systematists, the rules provided a compelling rationale for identifying geographical races or subspecies, a function that was also picked up by some physical anthropologists. More generally, the rules provided strong evidence for adaptation by natural selection. Supporters of the rules tacitly, or often explicitly, assumed that the clines described by the rules reflected adaptations for thermoregulation. This assumption was challenged by the physiologists Laurence Irving and Per Scholander based on their arctic research conducted after World War II. Their critique spurred a controversy played out in a series of articles in Evolution, in Ernst Mayr's Animal Species and Evolution, and in the writings of other prominent evolutionary biologists and physical anthropologists. Considering this episode highlights the complexity and ambiguity of important biological concepts such as adaptation, homeostasis, and self-regulation. It also demonstrates how different disciplinary orientations and styles of scientific research influenced evolutionary explanations, and the consequent difficulties of constructing a truly synthetic evolutionary biology in the decades immediately following World War II.

World Music Resources

ERIC Educational Resources Information Center

Beegle, Amy C.

2012-01-01

Access to world music resources such as videos and sound recordings have increased with the advent of YouTube and the efforts of music educators working closely with ethnomusicologists to provide more detailed visual and audio information about various musical practices. This column discusses some world music resources available for music…

[Bioethics and the French speaking world: an answer to globalization].

PubMed

Byk, Christian

2009-01-01

Are we able, today, to take a step closer to bringing together the French speaking world and bioethics by realizing that their association could provide a profound view of the current evolution of our world characterized by what is referred to as globalization? Could we be even more ambitious and register the specificity of the rapport between the French speaking world and bioethics confronted with this global phenomenon of deconstruction/reconstruction of the planetary order by setting as its path a dynamic balance, which is an integral part of the use of the French language and cultural diversity, a central point in a truly pluridisciplinary and pluralist bioethics?

Traditional Chinese medicine and the positive correlation with homeostatic evolution of human being: based on medical perspective.

PubMed

Wang, Jie-Hua

2012-08-01

Adaptation is an eternal theme of biological evolution. The paper aims at exploring the conception of positive correlation between traditional Chinese medicine (TCM) and human homeostatic evolution based on medical perspective. Discussions mainly involve TCM conforming to natural laws and natural evolution of life, spontaneous harmonization of yin and yang and operating system of human self-healing, modern human immunology and human endogenous immune function in TCM, self-homeostasis of human micro-ecological state and balance mechanism on regulating base in TCM, as well as adaptation-eternal theme of biological evolution and safeguarding adaptability-value of TCM. In perspective of medicine, theory and practice of TCM are in positive correlation with human homeostatic evolution, and what TCM tries to maintain is human intrinsic adaptive capability to disease and nature. Therefore, it is the core value of TCM, which is to be further studied, explored, realized and known to the world.

The whole genome sequence of the Mediterranean fruit fly, Ceratitis capitata (Wiedmann), reveals insights into the biology and adaptive evolution of a highly invasive pest species

USDA-ARS?s Scientific Manuscript database

The Mediterranean fruit fly is one of the most destructive agricultural pests throughout the world due to its broad host plant range that includes more than 260 different fruits, flowers, vegetables, and nuts. Host preferences vary in different regions of the world, which can be associated with its ...

Forest Technology Program, Lake City Community College: The Founding of a School, the Evolution of a College.

ERIC Educational Resources Information Center

Summers, Susan Robinson

Since 1947, Lake City Community College (LCCC) has evolved from a forest ranger school to a junior college to a true community college. After World War II, Lake City, the "Forestry Capitol of the World," converted a local air base into the Columbia Forestry School (CFS). The first few years were characterized by extremely low enrollment and…

Embedding the Form Generator in a Content Management System

NASA Astrophysics Data System (ADS)

Delgado, A.; Wicenec, A.; Delmotte, N.; Tejero, A.

2008-08-01

Given the tremendous amount of data generated by ESO's telescopes and the rapid evolution of the World Wide Web, the ESO archive web interface needs to offer more flexible services and advanced functionalities to a growing community of users all over the world. To achieve this endeavour, a query form generator is being developed inside a Content Management System. We present here a progress report.

Self-organization of chaos in mythology from a scientific point of view

NASA Astrophysics Data System (ADS)

Melker, Alexander I.

2007-04-01

In this contribution ancient Greek myths describing world's creation are analyzed as if they were a scientific paper. The 'paper' divided into the following parts: initial and boundary conditions, self-organization of chaos, world lines of self-organization, conclusion. It is shown that the self-organization of chaos consists of several stages during which two motive forces (attractive and repulsive) are generated, and totally disordered chaos transforms into partially ordered. It is found that there are five world lines of self-organization: water, light, cosmos-weather, water-fire, and State evolution.

The role of biology in planetary evolution: cyanobacterial primary production in low‐oxygen Proterozoic oceans

PubMed Central

Bryant, Donald A.; Macalady, Jennifer L.

2016-01-01

Summary Understanding the role of biology in planetary evolution remains an outstanding challenge to geobiologists. Progress towards unravelling this puzzle for Earth is hindered by the scarcity of well‐preserved rocks from the Archean (4.0 to 2.5 Gyr ago) and Proterozoic (2.5 to 0.5 Gyr ago) Eons. In addition, the microscopic life that dominated Earth's biota for most of its history left a poor fossil record, consisting primarily of lithified microbial mats, rare microbial body fossils and membrane‐derived hydrocarbon molecules that are still challenging to interpret. However, it is clear from the sulfur isotope record and other geochemical proxies that the production of oxygen or oxidizing power radically changed Earth's surface and atmosphere during the Proterozoic Eon, pushing it away from the more reducing conditions prevalent during the Archean. In addition to ancient rocks, our reconstruction of Earth's redox evolution is informed by our knowledge of biogeochemical cycles catalysed by extant biota. The emergence of oxygenic photosynthesis in ancient cyanobacteria represents one of the most impressive microbial innovations in Earth's history, and oxygenic photosynthesis is the largest source of O 2 in the atmosphere today. Thus the study of microbial metabolisms and evolution provides an important link between extant biota and the clues from the geologic record. Here, we consider the physiology of cyanobacteria (the only microorganisms capable of oxygenic photosynthesis), their co‐occurrence with anoxygenic phototrophs in a variety of environments and their persistence in low‐oxygen environments, including in water columns as well as mats, throughout much of Earth's history. We examine insights gained from both the rock record and cyanobacteria presently living in early Earth analogue ecosystems and synthesize current knowledge of these ancient microbial mediators in planetary redox evolution. Our analysis supports the hypothesis that anoxygenic photosynthesis, including the activity of metabolically versatile cyanobacteria, played an important role in delaying the oxygenation of Earth's surface ocean during the Proterozoic Eon. PMID:26549614

Science for Survival: The Modern Synthesis of Evolution and The Biological Sciences Curriculum Study

NASA Astrophysics Data System (ADS)

Green, Lisa Anne

In this historical dissertation, I examined the process of curriculum development in the Biological Sciences Curriculum Study (BSCS) in the United States during the period 1959-1963. The presentation of evolution in the high school texts was based on a more robust form of Darwinian evolution which developed during the 1930s and 1940s called "the modern synthesis of evolution." Building primarily on the work of historians Vassiliki Smocovitis and John L. Rudolph, I used the archival papers and published writings of the four architects of the modern synthesis and the four most influential leaders of the BSCS in regards to evolution to investigate how the modern synthetic theory of evolution shaped the BSCS curriculum. The central question was "Why was evolution so important to the BSCS to make it the central theme of the texts?" Important answers to this question had already been offered in the historiography, but it was still not clear why every citizen in the world needed to understand evolution. I found that the emphasis on natural selection in the modern synthesis shifted the focus away from humans as passive participants to the recognition that humans are active agents in their own cultural and biological evolution. This required re-education of the world citizenry, which was accomplished in part by the BSCS textbooks. I also found that BSCS leaders Grobman, Glass, and Muller had serious concerns regarding the effects of nuclear radiation on the human gene pool, and were actively involved in informing th public. Lastly, I found that concerns of 1950s reform eugenicists were addressed in the BSCS textbooks, without mentioning eugenics by name. I suggest that the leaders of the BSCS, especially Bentley Glass and Hermann J. Muller, thought that students needed to understand genetics and evolution to be able to make some of the tough choices they might be called on to make as the dominant species on earth and the next reproductive generation in the nuclear age. This was science for survival.

Cybernetics - The new Era Arrives

NASA Astrophysics Data System (ADS)

Sharma, Anil; Sengar, Chitransh; Bisht, Lalit; Sharma, Deepak

2012-12-01

The paper basically deals with the study of Cybernetics I, the history of evolution of this theory of this cyborg technology from the base to planting its roots in the future. The paper also presents a brief description about the use of this cyber technology in various felids known to the human world. Along with this is a description about the evolution of cybernetics as a cure to various medical problems.

Mesozoic mammals from Arizona: new evidence on Mammalian evolution.

PubMed

Jenkins, F A; Crompton, A W; Downs, W R

1983-12-16

Knowledge of early mammalian evolution has been based on Old World Late Triassic-Early Jurassic faunas. The discovery of mammalian fossils of approximately equivalent age in the Kayenta Formation of northeastern Arizona gives evidence of greater diversity than known previously. A new taxon documents the development of an angular region of the jaw as a neomorphic process, and represents an intermediate stage in the origin of mammalian jaw musculature.

Beyond aridification: multiple explanations for the elevated diversification of cacti in the New World Succulent Biome.

PubMed

Hernández-Hernández, Tania; Brown, Joseph W; Schlumpberger, Boris O; Eguiarte, Luis E; Magallón, Susana

2014-06-01

Succulent plants are widely distributed, reaching their highest diversity in arid and semi-arid regions. Their origin and diversification is thought to be associated with a global expansion of aridity. We test this hypothesis by investigating the tempo and pattern of Cactaceae diversification. Our results contribute to the understanding of the evolution of New World Succulent Biomes. We use the most taxonomically complete dataset currently available for Cactaceae. We estimate divergence times and utilize Bayesian and maximum likelihood methods that account for nonrandom taxonomic sampling, possible extinction scenarios and phylogenetic uncertainty to analyze diversification rates, and evolution of growth form and pollination syndrome. Cactaceae originated shortly after the Eocene-Oligocene global drop in CO2 , and radiation of its richest genera coincided with the expansion of aridity in North America during the late Miocene. A significant correlation between growth form and pollination syndrome was found, as well as a clear state dependence between diversification rate, and pollination and growth-form evolution. This study suggests a complex picture underlying the diversification of Cactaceae. It not only responded to the availability of new niches resulting from aridification, but also to the correlated evolution of novel growth forms and reproductive strategies. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

Philosophy and Sociology of Science Evolution and History

NASA Astrophysics Data System (ADS)

Rosen, Joe

The following sections are included: * Concrete Versus Abstract Theoretical Models * Introduction: concrete and abstract in kepler's contribution * Einstein's theory of gravitation and mach's principle * Unitary symmetry and the structure of hadrons * Conclusion * Dedication * Symmetry, Entropy and Complexity * Introduction * Symmetry Implies Abstraction and Loss of Information * Broken Symmetries - Imposed or Spontaneous * Symmetry, Order and Information * References * Cosmological Surrealism: More Than "Eternal Reality" Is Needed * Pythagoreanism in atomic, nuclear and particle physics * Introduction: Pythagoreanism as part of the Greek scientific world view — and the three questions I will tackle * Point 1: the impact of Gersonides and Crescas, two scientific anti-Aristotelian rebels * Point 2: Kepler's spheres to Bohr's orbits — Pythagoreanisms at last! * Point 3: Aristotle to Maupertuis, Emmy Noether, Schwinger * References * Paradigm Completion For Generalized Evolutionary Theory With Application To Epistemology * Evolution Fully Generalized * Entropy: Gravity as Model * Evolution and Entropy: Measures of Complexity * Extinctions and a Balanced Evolutionary Paradigm * The Evolution of Human Society - the Age of Information as example * High-Energy Physics and the World Wide Web * Twentieth Century Epistemology has Strong (de facto) Evolutionary Elements * The discoveries towards the beginning of the XXth Century * Summary and Conclusions * References * Evolutionary Epistemology and Invalidation * Introduction * Extinctions and A New Evolutionary Paradigm * Evolutionary Epistemology - Active Mutations * Evolutionary Epistemology: Invalidation as An Extinction * References

Early Precambrian crustal evolution of south India

NASA Technical Reports Server (NTRS)

Srinivasan, R.

1986-01-01

The Early Precambrian sequence in Karnataka, South India provides evidences for a distinct trend of evolution which differs from trends exhibited in many other Early Precambrian regions of the world. The supracrustal rock associations preserved in greenstone belts and as inclusions in gneisses and granulites suggest the evolution of the terrain from a stable to a mobile regime. The stable regime is represented by (1) layered ultramafic-mafic complexes, (2) orthoquartzite-basalt-rhyodacite-iron formation, and (30 ortho-quartzite-carbonate-Mn-Fe formation. The mobile regime, which can be shown on sedimentological grounds to have succeeded the stable regime, witnessed the accumulation of a greywacke-pillow basalt-dacite-rhyolite-iron formation association. Detrital sediments of the stable zone accumulated dominantly in fluvial environment and the associated volcanics are ubaerial. The volcanics of the stable regime are tholeiites derived from a zirconium and LREE-enriched sources. The greywackes of the mobile regime are turbidities, and the volcanic rocks possess continental margin (island-arc or back-arc) affinity; they show a LREE depleted to slightly LREE-enriched pattern. The evolution from a stable to a mobile regime is in contrast to the trend seen in most other regions of the world, where an early dominantly volcanic association of a mobile regime gives way upward in the sequence to sediments characteristic of a stable regime.

On the topology of the world exchange arrangements web

NASA Astrophysics Data System (ADS)

Li, Xiang; Jin, Yu Ying; Chen, Guanrong

2004-11-01

Exchange arrangements among different countries over the world are foundations of the world economy, which generally stand behind the daily economic evolution. As the first study of the world exchange arrangements web (WEAW), we built a bipartite network with countries as one type of nodes and currencies as the other, and found it to have a prominent scale-free feature with a power-law degree distribution. In a further empirical study of the currency section of the WEAW, we calculated the clustering coefficients, average nearest-neighbors degree, and average shortest distance. As an essential economic network, the WEAW is found to be a correlated disassortative network with a hierarchical structure, possessing a more prominent scale-free feature than the world trade web (WTW).

Gully evolution and geomorphic adjustments of badlands to reforestation

PubMed Central

Ballesteros Cánovas, J. A.; Stoffel, M.; Martín-Duque, J. F.; Corona, C.; Lucía, A.; Bodoque, J. M.; Montgomery, D. R.

2017-01-01

Badlands and gullied areas are among those geomorphic environments with the highest erosion rates worldwide. Nevertheless, records of their evolution and their relations with anthropogenic land transformation are scarcer. Here we combine historical data with aerial photographs and tree-ring records to reconstruct the evolution of a badland in a Mediterranean environment of Central Spain. Historical sources suggest an anthropogenic origin of this badland landscape, caused by intense quarrying activities during the 18th century. Aerial photographs allowed detection of dramatic geomorphic changes and the evolution of an emerging vegetation cover since the 1960s, due to widespread reforestation. Finally, tree-ring analyses of exposed roots allowed quantification of recent channel incision of the main gully, and sheet erosion processes. Our results suggest that reforestation practices have influenced the initiation of an episode of incision in the main channel in the 1980s, through the hypothesized creation of disequilibrium in water-sediment balance following decoupling of hillslopes from channel processes. These findings imply an asymmetry in the geomorphic response of badlands to erosion such that in the early evolution stages, vegetation removal results in gullying, but that reforestation alone does not necessarily stabilize the landforms and may even promote renewed incision. PMID:28327591

Evolution of Protein Synthesis from an RNA World

PubMed Central

Noller, Harry F.

2012-01-01

SUMMARY Because of the molecular complexity of the ribosome and protein synthesis, it is a challenge to imagine how translation could have evolved from a primitive RNA World. Two specific suggestions are made here to help to address this, involving separate evolution of the peptidyl transferase and decoding functions. First, it is proposed that translation originally arose not to synthesize functional proteins, but to provide simple (perhaps random) peptides that bound to RNA, increasing its available structure space, and therefore its functional capabilities. Second, it is proposed that the decoding site of the ribosome evolved from a mechanism for duplication of RNA. This process involved homodimeric “duplicator RNAs,” resembling the anticodon arms of tRNAs, which directed ligation of trinucleotides in response to an RNA template. PMID:20610545

Reflections on relationships between national and world events and development of dermatology. Venezuela as a model.

PubMed

Goihman-Yahr, Mauricio

2013-11-01

From a personal vantage, the author tries to understand evolution of medicine and dermatology as relating to political, ideological,and economic factors.He analyzes the evolution of Venezuelan Dermatology research and practice from 1936 to present, relating it to the events that have taken place in that country during this period and integrating the latter to events in the world. There is a close relationship between Venezuelan and US history particularly since the late nineteen-thirties.Physicians in general and dermatologists in particular should not dismiss or just bear the events that take place in the society as a whole. They should try to influence them by acting in harmony with forces that propitiate freedom, rule of law, free inquiry, and meritocracy.

Research Fellows | NREL

Science.gov Websites

years and has contributed greatly to world-record efficiencies in various photovoltaic technologies is a world-renowned expert in the fields of multijunction PV, concentrator PV, and PV reliability Publications Photo of Mark O'Malley Mark O'Malley SENIOR RESEARCH FELLOW Mark O'Malley is a world authority on

The Physics of Open Ended Evolution

NASA Astrophysics Data System (ADS)

Adams, Alyssa M.

What makes living systems different than non-living ones? Unfortunately this question is impossible to answer, at least currently. Instead, we must face computationally tangible questions based on our current understanding of physics, computation, information, and biology. Yet we have few insights into how living systems might quantifiably differ from their non-living counterparts, as in a mathematical foundation to explain away our observations of biological evolution, emergence, innovation, and organization. The development of a theory of living systems, if at all possible, demands a mathematical understanding of how data generated by complex biological systems changes over time. In addition, this theory ought to be broad enough as to not be constrained to an Earth-based biochemistry. In this dissertation, the philosophy of studying living systems from the perspective of traditional physics is first explored as a motivating discussion for subsequent research. Traditionally, we have often thought of the physical world from a bottom-up approach: things happening on a smaller scale aggregate into things happening on a larger scale. In addition, the laws of physics are generally considered static over time. Research suggests that biological evolution may follow dynamic laws that (at least in part) change as a function of the state of the system. Of the three featured research projects, cellular automata (CA) are used as a model to study certain aspects of living systems in two of them. These aspects include self-reference, open-ended evolution, local physical universality, subjectivity, and information processing. Open-ended evolution and local physical universality are attributed to the vast amount of innovation observed throughout biological evolution. Biological systems may distinguish themselves in terms of information processing and storage, not outside the theory of computation. The final research project concretely explores real-world phenomenon by means of mapping dominance hierarchies in the evolution of video game strategies. Though the main question of how life differs from non-life remains unanswered, the mechanisms behind open-ended evolution and physical universality are revealed.

Supporting the planning for the evolution of the EOSDIS through an in-depth understanding of user requirements for NASA's world-class Earth science data system

NASA Astrophysics Data System (ADS)

Griffin, V. L.; Behnke, J.; Maiden, M.; Fontaine, K.

2004-12-01

NASA is planning for the evolution of the Earth Observation System Data and Information System (EOSDIS), a large, complex data system currently supporting over 18 operational NASA satellite missions including the flagship EOS missions: Terra, Aqua, and Aura. A critical underpinning for the evolution planning is developing thorough knowledge of the EOSDIS users and how they use the EOSDIS products in their research and or applications endeavors. This paper provides charts and tables of results from NASA studies that characterized our users, data and techniques. Using these metrics, other projects can apply NASA's 'lessons learned' to the development and operations of their data systems. In 2004, NASA undertook an intensive study of the users and usage of EOSDIS data. The study considered trends in the types and levels of EOS data products being ordered, the expanding number of users requesting products, and the "domains" of those users. The study showed that increasing numbers of users are using the validated, geophysical products produced from the radiance measurements recorded by the EOS instruments; while there remains a steady demand for the radiance products themselves. In 2003, over 2.1 million individuals contacted EOSDIS (as identified by unique email and/or URL) with just over 10% requesting a product or service. The users came from all sectors including 40% from more than 125 countries outside the U.S. University researchers and students (.edu) received over 40% of the some 29 million data and information products disseminated by EOSDIS. The trend in method of delivery for EOSDIS data has been away from receiving data on hard media (tapes, CD-ROM, etc.) to receiving the data over the network. Over 75% of the EOSDIS data products were disseminated via electronic means in 2003 contrasted with just under 30% in 2000. To plan for system-wide evolution you need to know whether the system is meeting the users' needs and expectations. Thus, in 2004 NASA commissioned a comprehensive survey to determine user satisfaction using the American Customer Satisfaction Index (ACSI) approach. The results show that, overall, the users are highly satisfied with the EOSDIS systems and services as the EOSDIS ACSI score outperformed both the averages for U.S. companies and for Federal Agencies. Noteworthy was the fact that there was no statistical difference in the quality scores received by the various EOSDIS data centers. The response indicated that customer support provided by the EOSDIS Distributed Active Archive Centers (DAACs) is "world class" and that a very high number of users intend to use EOSDIS in the future (90%) and to recommend it to their colleagues (86%). The survey highlighted areas that, if improved, could lead to increased user satisfaction, including overall product quality, product documentation, and product selection and ordering processes. These results will be factored into NASA's evolution planning.

Short- and Long-term Evolutionary Dynamics of Bacterial Insertion Sequences: Insights from Wolbachia Endosymbionts

PubMed Central

Cerveau, Nicolas; Leclercq, Sébastien; Leroy, Elodie; Bouchon, Didier; Cordaux, Richard

2011-01-01

Transposable elements (TE) are one of the major driving forces of genome evolution, raising the question of the long-term dynamics underlying their evolutionary success. Long-term TE evolution can readily be reconstructed in eukaryotes, thanks to many degraded copies constituting genomic fossil records of past TE proliferations. By contrast, bacterial genomes usually experience high sequence turnover and short TE retention times, thereby obscuring ancient TE evolutionary patterns. We found that Wolbachia bacterial genomes contain 52–171 insertion sequence (IS) TEs. IS account for 11% of Wolbachia wRi, which is one of the highest IS genomic coverage reported in prokaryotes to date. We show that many IS groups are currently expanding in various Wolbachia genomes and that IS horizontal transfers are frequent among strains, which can explain the apparent synchronicity of these IS proliferations. Remarkably, >70% of Wolbachia IS are nonfunctional. They constitute an unusual bacterial IS genomic fossil record providing direct empirical evidence for a long-term IS evolutionary dynamics following successive periods of intense transpositional activity. Our results show that comprehensive IS annotations have the potential to provide new insights into prokaryote TE evolution and, more generally, prokaryote genome evolution. Indeed, the identification of an important IS genomic fossil record in Wolbachia demonstrates that IS elements are not always of recent origin, contrary to the conventional view of TE evolution in prokaryote genomes. Our results also raise the question whether the abundance of IS fossils is specific to Wolbachia or it may be a general, albeit overlooked, feature of prokaryote genomes. PMID:21940637

Short- and long-term evolutionary dynamics of bacterial insertion sequences: insights from Wolbachia endosymbionts.

PubMed

Cerveau, Nicolas; Leclercq, Sébastien; Leroy, Elodie; Bouchon, Didier; Cordaux, Richard

2011-01-01

Transposable elements (TE) are one of the major driving forces of genome evolution, raising the question of the long-term dynamics underlying their evolutionary success. Long-term TE evolution can readily be reconstructed in eukaryotes, thanks to many degraded copies constituting genomic fossil records of past TE proliferations. By contrast, bacterial genomes usually experience high sequence turnover and short TE retention times, thereby obscuring ancient TE evolutionary patterns. We found that Wolbachia bacterial genomes contain 52-171 insertion sequence (IS) TEs. IS account for 11% of Wolbachia wRi, which is one of the highest IS genomic coverage reported in prokaryotes to date. We show that many IS groups are currently expanding in various Wolbachia genomes and that IS horizontal transfers are frequent among strains, which can explain the apparent synchronicity of these IS proliferations. Remarkably, >70% of Wolbachia IS are nonfunctional. They constitute an unusual bacterial IS genomic fossil record providing direct empirical evidence for a long-term IS evolutionary dynamics following successive periods of intense transpositional activity. Our results show that comprehensive IS annotations have the potential to provide new insights into prokaryote TE evolution and, more generally, prokaryote genome evolution. Indeed, the identification of an important IS genomic fossil record in Wolbachia demonstrates that IS elements are not always of recent origin, contrary to the conventional view of TE evolution in prokaryote genomes. Our results also raise the question whether the abundance of IS fossils is specific to Wolbachia or it may be a general, albeit overlooked, feature of prokaryote genomes.

World War II, tantalum, and the evolution of modern cranioplasty technique.

PubMed

Flanigan, Patrick; Kshettry, Varun R; Benzel, Edward C

2014-04-01

Cranioplasty is a unique procedure with a rich history. Since ancient times, a diverse array of materials from coconut shells to gold plates has been used for the repair of cranial defects. More recently, World War II greatly increased the demand for cranioplasty procedures and renewed interest in the search for a suitable synthetic material for cranioprostheses. Experimental evidence revealed that tantalum was biologically inert to acid and oxidative stresses. In fact, the observation that tantalum did not absorb acid resulted in the metal being named after Tantalus, the Greek mythological figure who was condemned to a pool of water in the Underworld that would recede when he tried to take a drink. In clinical use, malleability facilitated a single-stage cosmetic repair of cranial defects. Tantalum became the preferred cranioplasty material for more than 1000 procedures performed during World War II. In fact, its use was rapidly adopted in the civilian population. During World War II and the heyday of tantalum cranioplasty, there was a rapid evolution in prosthesis implantation and fixation techniques significantly shaping how cranioplasties are performed today. Several years after the war, acrylic emerged as the cranioplasty material of choice. It had several clear advantages over its metallic counterparts. Titanium, which was less radiopaque and had a more optimal thermal conductivity profile (less thermally conductive), eventually supplanted tantalum as the most common metallic cranioplasty material. While tantalum cranioplasty was popular for only a decade, it represented a significant breakthrough in synthetic cranioplasty. The experiences of wartime neurosurgeons with tantalum cranioplasty played a pivotal role in the evolution of modern cranioplasty techniques and ultimately led to a heightened understanding of the necessary attributes of an ideal synthetic cranioplasty material. Indeed, the history of tantalum cranioplasty serves as a model for innovative thinking and adaptive technology development.

A Jurassic wood providing insights into the earliest step in Ginkgo wood evolution.

PubMed

Jiang, Zikun; Wang, Yongdong; Philippe, Marc; Zhang, Wu; Tian, Ning; Zheng, Shaolin

2016-12-16

The fossil record of Ginkgo leaf and reproductive organs has been well dated to the Mid-Jurassic (170 Myr). However, the fossil wood record that can safely be assigned to Ginkgoales has not yet been reported from strata predating the late Early Cretaceous (ca. 100 Myr). Here, we report a new fossil wood from the Mid-Late Jurassic transition deposit (153-165 Myr) of northeastern China. The new fossil wood specimen displays several Ginkgo features, including inflated axial parenchyma and intrusive tracheid tips. Because it is only slightly younger than the oldest recorded Ginkgo reproductive organs (the Yima Formation, 170 Myr), this fossil wood very probably represents the oldest bona fide fossil Ginkgo wood and the missing ancestral form of Ginkgo wood evolution.

Le Silurien de la région d'Oulad Abbou (Meseta occidentale, Maroc) : une sédimentation péritidale sous contrôle tectonique

NASA Astrophysics Data System (ADS)

Attou, Ahmed; Hamoumi, Naima

2004-07-01

In the Oulad Abbou syncline, western coastal Meseta, the Silurian deposits exhibit siliciclastic or mixed siliciclastic/carbonate tidal facies that recorded alkaline basalt flows and syn-sedimentary deformations. These facies are staked into peritidal shallowing upward sequences reflecting the evolution from an infratidal to a supratidal environment. These sequences recorded low-amplitude and high-frequency sea-level variations. The built-up of these rhythmic sequences is related to distensive tectonic that allowed the development of isolated platform from extensive siliciclastic influx. This tectonic event is well recorded in the palaeogeographic evolution of the northern Gondwana platform during the Lower Palaeozoic time. To cite this article: A. Attou, N. Hamoumi, C. R. Geoscience 336 (2004).

A Jurassic wood providing insights into the earliest step in Ginkgo wood evolution

NASA Astrophysics Data System (ADS)

Jiang, Zikun; Wang, Yongdong; Philippe, Marc; Zhang, Wu; Tian, Ning; Zheng, Shaolin

2016-12-01

The fossil record of Ginkgo leaf and reproductive organs has been well dated to the Mid-Jurassic (170 Myr). However, the fossil wood record that can safely be assigned to Ginkgoales has not yet been reported from strata predating the late Early Cretaceous (ca. 100 Myr). Here, we report a new fossil wood from the Mid-Late Jurassic transition deposit (153-165 Myr) of northeastern China. The new fossil wood specimen displays several Ginkgo features, including inflated axial parenchyma and intrusive tracheid tips. Because it is only slightly younger than the oldest recorded Ginkgo reproductive organs (the Yima Formation, 170 Myr), this fossil wood very probably represents the oldest bona fide fossil Ginkgo wood and the missing ancestral form of Ginkgo wood evolution.

Lunar interactions: Abstracts of papers presented at the Conference on Interactions of the Interplanetary Plasma with the Modern and Ancient Moon

NASA Technical Reports Server (NTRS)

Criswell, D. R. (Editor); Freeman, J. W. (Editor)

1974-01-01

Reviewed are the active mechanisms relating the moon to its environment and the linkage between these mechanisms and their records in the lunar sample and geophysical data. Topics: (1) large scale plasma interactions with the moon and non-magnetic planets; (2) ancient and present day lunar surface magnetic and electric fields; (3) dynamics and evolution of the lunar atmosphere; (4) evolution of the solar plasma; (5) lunar record of solar radiations; (6) non-meteoritic and meteoritic disturbance and transport of lunar surface materials; and (7) future lunar exploration.

Is globalization undermining the welfare state? The evolution of the welfare state in developed capitalist countries during the 1990s.

PubMed

Navarro, Vicente; Schmitt, John; Astudillo, Javier

2004-01-01

The authors analyze the evolution of macro-indicators of social and economic well-being during the 1990s in the majority of developed capitalist countries, grouped according to their dominant political traditions since the end of World War II. Their analysis shows that, despite the economic globalization of commerce and finance, "politics still matters" in explaining the evolution of the welfare states and labor markets in these countries; the impact of the globalization of financial capital in forcing reductions in the financial resources available for welfare state purposes has been exaggerated.

Cryptic genetic variation, evolution's hidden substrate

PubMed Central

Paaby, Annalise B.; Rockman, Matthew V.

2016-01-01

Cryptic genetic variation is invisible under normal conditions but fuel for evolution when circumstances change. In theory, CGV can represent a massive cache of adaptive potential or a pool of deleterious alleles in need of constant suppression. CGV emerges from both neutral and selective processes and it may inform how human populations respond to change. In experimental settings, CGV facilitates adaptation, but does it play an important role in the real world? We review the empirical support for widespread CGV in natural populations, including its potential role in emerging human diseases and the growing evidence of its contribution to evolution. PMID:24614309

Specimens as records: scientific practice and recordkeeping in natural history research.

PubMed

Ilerbaig, Juan

2010-01-01

For the past two decades, scholars in archival science have begun to question traditional assumptions about the nature of the record. Drawing on theories from fields such as sociology, organization theory, and science studies, and on their own ethnographic studies, they propose more inclusive definitions and widening the contexts of analysis of record making and recordkeeping. This paper continues this critical consideration of the concept of record by examining the nature of nonprototypical records in the scientific world. The paper focuses on the system of specimens and field notes established by biologist Joseph Grinnell at the Museum of Vertebrate Zoology (University of California, Berkeley) as a means of examining several aspects of the nature of the scientific record: materiality, representation, and the triad evidence/memory/accountability. Focusing on the creation and management of these scientific records, the paper argues that further analyses of scientific record making and recordkeeping are bound to benefit both scientific work, which depends more and more on databases and archives, as well as archival science, which is becoming more relevant beyond its traditional realm of the legal/business/administrative world.

Future Evolution of Virtual Worlds as Communication Environments

NASA Astrophysics Data System (ADS)

Prisco, Giulio

Extensive experience creating locations and activities inside virtual worlds provides the basis for contemplating their future. Users of virtual worlds are diverse in their goals for these online environments; for example, immersionists want them to be alternative realities disconnected from real life, whereas augmentationists want them to be communication media supporting real-life activities. As the technology improves, the diversity of virtual worlds will increase along with their significance. Many will incorporate more advanced virtual reality, or serve as major media for long-distance collaboration, or become the venues for futurist social movements. Key issues are how people can create their own virtual worlds, travel across worlds, and experience a variety of multimedia immersive environments. This chapter concludes by noting the view among some computer scientists that future technologies will permit uploading human personalities to artificial intelligence avatars, thereby enhancing human beings and rendering the virtual worlds entirely real.

The RNA-world and co-evolution hypotheses and the origin of life: Implications, research strategies and perspectives

NASA Astrophysics Data System (ADS)

Lahav, Noam

1993-12-01

The applicability of the RNA-world and co-evolution hypotheses to the study of the very first stages of the origin of life is discussed. The discussion focuses on the basic differences between the two hypotheses and their implications, with regard to the reconstruction methodology, ribosome emergence, balance between ribozymes and protein enzymes, and their major difficulties. Additional complexities of the two hypotheses, such as membranes and the energy source of the first reactions, are not treated in the present work. A central element in the proposed experimental strategies is the study of the catalytic activities of very small peptides and RNA-like oligomers, according to existing, as well as to yet-to-be-invented scenarios of the two hypotheses under consideration. It is suggested that the noveldirected molecular evolution technology, andmolecular computational modeling, can be applied to this research. This strategy is assumed to be essential for the suggested goal of future studies of the origin of life, namely, the establishment of a ‘Primordial Darwinian entity’.

Habitability of super-Earth planets around other suns: models including Red Giant Branch evolution.

PubMed

von Bloh, W; Cuntz, M; Schröder, K-P; Bounama, C; Franck, S

2009-01-01

The unexpected diversity of exoplanets includes a growing number of super-Earth planets, i.e., exoplanets with masses of up to several Earth masses and a similar chemical and mineralogical composition as Earth. We present a thermal evolution model for a 10 Earth-mass planet orbiting a star like the Sun. Our model is based on the integrated system approach, which describes the photosynthetic biomass production and takes into account a variety of climatological, biogeochemical, and geodynamical processes. This allows us to identify a so-called photosynthesis-sustaining habitable zone (pHZ), as determined by the limits of biological productivity on the planetary surface. Our model considers solar evolution during the main-sequence stage and along the Red Giant Branch as described by the most recent solar model. We obtain a large set of solutions consistent with the principal possibility of life. The highest likelihood of habitability is found for "water worlds." Only mass-rich water worlds are able to realize pHZ-type habitability beyond the stellar main sequence on the Red Giant Branch.

The RNA-world and co-evolution hypothesis and the origin of life: Implications, research strategies and perspectives

NASA Technical Reports Server (NTRS)

Lahav, Noam

1993-01-01

The applicability of the RNA-world and co-evolution hypothesis to the study of the very first stages of the origin of life is discussed. The discussion focuses on the basic differences between the two hypotheses and their implications, with regard to the reconstruction methodology, ribosome emergence, balance between ribozymes and protein enzymes, and their major difficultites. Additional complexities of the two hypotheses, such as membranes and the energy source of the first reactions, are not treated in the present work. A central element in the proposed experimental strategies is the study of the catalytic activites of very small peptides and RNA-like oligomers, according to existing, as well as to yet-to-be-invented scenarios of the two hypothesis under consideration. It is suggested that the novel directed molecular evolution technology, and molecular computational modeling, can be applied to this research. This strategy is assumed to be essential for the suggested goal of future studies of the origin of life, namely, the establishment of a `Primordial Darwinian entity'.

Geoethics in the Years of Living Dangerously

NASA Astrophysics Data System (ADS)

Schmitt, J.

2014-12-01

The geosciences lag behind the ecologic and atmospheric sciences in addressing the major scientific and societal ethical issues facing the inhabitants of planet Earth. Regardless, major emerging ethical issues at the interface of the earth system with society demand geoscientist engagement. These include climate change, extinction and biodiversity decline, transformation of terrestrial landscapes and related impacts on ocean ecosystems, and the consequential resonance of these changes on human health, economic and environmental justice, and political stability. The societal factors driving these issues derive from a world view founded on speciesism (human dominion), utilitarian use of resources, unquestioned population and economic growth, and human difficulty in perceiving deep time and large spatial scale. Accommodation of the supernatural, mythical, and political realms with science has led to widespread conflation of scientific consensus with opinion, driving denial of both climate change and evolution. Future success in rationally addressing these ethical conundrums requires geoscientist engagement across the social, political, economic, ethical, philosophical, and historical realms of inquiry. Geoscientists must be well-versed in earth system science principles and the major geologic concepts relevant to understanding anthropogenic change including deep time, the fossil record of evolution, and changes across multiple spatial and temporal scales that transcend human experience. They must also: 1) confront the global population issue, using the archaeological and historical record of its recent rapidly accelerated growth, especially as it impacts resource consumption and earth system function, 2) forcefully address the effects of agriculture on the atmosphere, terrestrial and marine ecosystems, disease, urbanization, and political instability, 3) apply the synthetic principles of conservation biology, including ecosystem science, geoecology, and major advances in understanding the cognitive abilities and social dimensions of non-human animals to address ethical issues involving humanity's impact on the Earth's biota, and 4) work to end the accommodation of belief systems with science that invariably leads to denialism and historical confabulation.

The Evolution of Seabirds in the Humboldt Current: New Clues from the Pliocene of Central Chile

PubMed Central

Chávez Hoffmeister, Martín; Carrillo Briceño, Jorge D.; Nielsen, Sven N.

2014-01-01

Background During the last decade, new Neogene fossil assemblages from South America have revealed important clues about the evolution of seabird faunas in one of the major upwelling systems of the world: the Humboldt Current. However, most of this record comes from arid Northern Chile and Southern Peru and, in consequence, our knowledge of the evolutionary history of seabirds in the temperate transitional zone is negligible. A new Late Pliocene assemblage of fossil birds from the coastal locality of Horcon in Central Chile offers a unique opportunity to fill this gap. Principal Findings Isolated bones of a medium-sized penguin are the most abundant bird remains. Morphological and cladistic analyses reveal that these specimens represent a new species of crested penguin, Eudyptes calauina sp. nov. Eudyptes is a penguin genus that inhabit temperate and subantarctic regions and currently absent in central Chile. Additionally, a partial skeleton of a small species of cormorant and a partial tarsometatarsus of a sooty shearwater have been identified. Conclusion/Significance The Horcon fossils suggest the existence of a mixed avifauna in central Chile during the Pliocene in concordance with the latitudinal thermal gradient. This resembles the current assemblages from the transitional zone, with the presence of species shared with Northern Chile and Southern Peru and a previously unrecorded penguin currently absent from the Humboldt System but present in the Magellanic region. Comparison of Pliocene seabird diversity across the Pacific coast of South America shows that the Horcon avifauna represents a distinctive assemblage linking the living faunas with the Late Miocene ones. A comparison with the fossil record near the Benguela Current (west coast of southern Africa) suggests that the thermic gradient could play an important role in the preservation of a higher diversity of cold/temperate seabirds in the Humboldt Current. PMID:24621560

The record of Tethyan planktonic foraminifera at the early Paleogene hyperthermal events and Middle Eocene Climatic Optimum in northeastern Italy: are they comparable?

NASA Astrophysics Data System (ADS)

Luciani, Valeria; Giusberti, Luca; Agnini, Claudia; Fornaciari, Eliana; Rio, Domenico

2010-05-01

The early Paleogene is one of the more climatically and evolutionary dynamic periods in the Earth history that records a pronounced warming trend peaking in the Early Eocene, and a successive composite transition towards the modern icehouse world. Ever increasingly scientific attention is dedicated to definitely comprehend timing, nature and characters of the complex, non-linear evolution of the Paleogene climate. Several complete and expanded Paleogene successions (Forada, Possagno, Alano, Farra), with a sound magneto-biochronostratigraphic and stable isotope record crop out in the Venetian Southern Alps (Northeast Italy). Recent studies (Giusberti et. al., 2007; Luciani et al., 2007; Agnini et al., 2008) and unpublished data document the presence in these section of the main short-lived warming events (hyperthermals) of the Eocene (Paleocene-Eocene Thermal Maximum, PETM, ca 55 Ma, Eocene Layer of Mysterious Origin (ELMO, ca 53,6 Ma), X-event (ca 52.5 Ma), of the Early Eocene Climatic Optimum (EECO, ca 50-52 Ma) and of the Middle Eocene Climatic Optimum (MECO, ca 40 Ma; Zachos et al., 2001. 2008). All these events are typified by marked negative shifts in δ13C curves that correspond to carbonate decrease related to rise of the carbonate compensation depth in turn induced by large introduction in the ocean-atmosphere system of CO2. Common features to the warming events are pronounced and complex changes in planktonic foraminiferal assemblages, indicating strong environmental perturbations that perfectly parallel the variations of the stable isotope curves in all the examined events. These strict correspondences indicate close cause-effect relationships between changes in environmental conditions and modifications of the assemblages. Our analysis shows that the most striking variations are recorded by the PETM and MECO assemblages that reflect highly perturbed environments. The ELMO, X-event and EECO exhibit planktic foraminiferal responses that are similar to, though less intense than, those observed across the PETM and the MECO. In addition, sedimentological and quantitative micropaleontological data from the hyperthermal events from the Venetian Southern Alps essentially suggest as the main response to the pronounced warmth, increased weathering and runoff as well as sea surface eutrophication. A pronounced shift from relatively oligotrophic to eutrophic, opportunist planktonic foraminiferal assemblages was observed at the MECO as well, thus showing analogies with the hyperthermal events recorded in the same area. The taxa indicating eutrophic environmental conditions are however different at the MECO from the Alano section; on the other hand we can expect that the planktonic foraminiferal taxa indicating analogous scenarios might be different in different Eocene time-intervals. Remarkably, the PETM and MECO events record a significant occurrence of giant and malformed foraminifera, evidence of transient alteration in the ocean chemistry, including possible pH oscillations and increase in trace metal content. Our data suggests therefore that a major threshold in the photic zone ocean chemistry has been passed only for those prominent events. In conclusion, from the biotic response to the hyperthermal events, to the EECO and MECO we deduce that the most important effect of pronounced warming, that is the aspect common to all these events, has been the eutrophication of surface waters, as a consequence of modification in the hydrological cycle. The location adjacent to land masses of the studied Tethyan setting evidently facilitated the terrigenous input that was apparently the main responsible for the increase in nutrient availability during the cited Paleogene warming events. Finally, several lines of evidence indicate that PETM, EECO and MECO were linked to permanent changes in planktonic foraminiferal evolution beside the transient, ecologically controlled variations. Even though the true mechanisms forcing evolution of life on Earth are still unexplained, our record of the major climatic Paleogene events suggests a close interaction between global climate and biological evolution. REFERENCES Agnini et al., 2008. Rend. Soc. Geol. It. 4, 5-12. Giusberti et., 2007; Geol. Soc. Am. Bull. 119, 391-412. Luciani et al., 2007. Mar. Micopaleont. 64, 189-214. Zachos et al., 2001. Science 292, 686-693. Zachos et al 2008 Nature 451, 279-283.

Paleoenvironmental change as seen from a multiproxy perspective in the West Turkana Kaitio core (WTK13), Kenya

NASA Astrophysics Data System (ADS)

Beck, C. C.; Feibel, C. S.; Lupien, R.; Yost, C. L.; Rucina, S.; Russell, J. M.; Deino, A. L.; Sier, M.; Cohen, A. S.; Campisano, C. J.

2017-12-01

The Hominin Sites and Paleolakes Drilling Project's (HSPDP) primary goal is to provide high quality environmental records to test whether and how Earth system dynamics influenced the evolution of hominins in Africa. To this end, multiproxy records from individual basins are essential to understanding how paleoenvironments changed in relation to shifts in the climatic and/or tectonic regimes both locally on a basin-scale and regionally across East Africa. Because of its rich combination of paleoanthropologic and geologic data, the West Turkana Kaitio (WTK13) core is an important component of this synthesis. Using a combination of tephra chronology and paleomagnetic data, the core has been dated to 1.87-1.37 Ma. The sedimentology records deposition on a dynamic lacustrine margin becoming more influenced by channel and floodplain processes through time. Multiproxy records provide a window into paleoevironments of the Turkana Basin that operated on shorter time scales than this dominant first-order facies shift. Processional cycles (21 kyr) are picked up by indicator records where the preservation of the archive was good enough to allow for high-resolution analysis. However, interestingly, the biomarker record suggests that the hydroclimate of the Turkana Basin, while highly variable at the Milankovitch-scale, exhibits no directional trend in the mean values towards wetter or drier conditions. The combined phytolith and pollen records suggest that grasses, albeit with fluctuating abundances of C4 mesophytic and C4 xerophytic taxa, dominated the landscape throughout most of the core. This indicates that despite climatic variability, resource availability may have maintained some general consistency for hominins in the area. Ultimately, the time period spanned by the WTK13 record is significant for our understanding of hominin evolution as it covers an interval of increasing aridity on the African continent as observed in distal marine records. This synthesis demonstrates how paleoenvironment of the Turkana Basin responded to these broader paleoclimatic trends. With this core, it is possible to refine this record both spatially, by looking directly at a basin where hominin evolution occurred, and temporally, by sampling on a sub-Milankovitch scale.

Automated Analysis of Zooplankton Size and Taxonomic Composition.

DTIC Science & Technology

1998-07-01

Gallager, and P. Alatalo. Seasonal evolution of plankton and particle distributions across Georges Bank as measured using the Video Plankton Recorder... pteropods , and larvaceans estimated from concurrent Video Plankton Recorder and MOCNESS tows in the stratified region of Georges Bank. Deep Sea Res

Study on Capturing Functional Requirements of the New Product Based on Evolution

NASA Astrophysics Data System (ADS)

Liu, Fang; Song, Liya; Bai, Zhonghang; Zhang, Peng

In order to exist in an increasingly competitive global marketplace, it is important for corporations to forecast the evolutionary direction of new products rapidly and effectively. Most products in the world are developed based on the design of existing products. In the product design, capturing functional requirements is a key step. Function is continuously evolving, which is driven by the evolution of needs and technologies. So the functional requirements of new product can be forecasted based on the functions of existing product. Eight laws of function evolution are put forward in this paper. The process model of capturing the functional requirements of new product based on function evolution is proposed. An example illustrates the design process.

Optimizing combined GPR, OSL and LiDAR (GOaL) to extract paleoenvironmental records and decipher shoreline evolution

NASA Astrophysics Data System (ADS)

Dougherty, A. J.; Choi, J. H.; Turney, C. S.; Dosseto, A.

2017-12-01

Records of past sea levels, storms, sediment supply and their impacts on the coastline are crucial for projecting likely shoreline changes resulting from anthropogenic warming. High-resolution geophysics, geochronology, and remote sensing techniques offer an optimal way to extract these records and decipher shoreline evolution. These methods include Light Detection and Ranging (LiDAR for imaging barrier morphologies in three dimensions), Ground Penetrating Radar (GPR for detecting paleo-dune, beach and nearshore stratigraphy) and Optically Stimulated Luminescence (OSL for dating deposition of sand grains along paleoshorelines). Each of these teqniques have been applied to coastal research over the decades since they were first introduced. Recently there has been a rapid increase their use since LiDAR became more available, GPR more user-friendly, and OSL more accessible. These methods have the potential to produce both detailed and voluminous datasets that can overwhelm or obscure significant features, such that discrepancies in analysis and/or presentation may lead to erroneous interpretations. In contrast, when utilized correctly on prograded barriers these methods (independently or in various combinations) have produced storm records, constructed sea-level curves, quantified sediment budgets, and deciphered coastal evolution. Therefore, combining the application of GPR, OSL, and LiDAR (GOaL) on one prograded barrier has the potential to generate detailed records of storms, sea level, and sediment supply for that coastline. Obtaining this GOaL hat-trick can provide valuable insights into how these three factors influenced past and future barrier evolution. Here we argue that systematically achieving GOaL hat-tricks on some of the 300+ prograded barriers worldwide would allow us to disentangle local patterns of sediment supply from regional effects of storms or global changes in sea level, allowing direct comparison to climate proxy records. To fully realize this aim requires standardization of methods to optimize results. The impetus for this initiative is to establish a framework for consistent data analysis that maximizes the potential of GOaL to contribute to climate change research and assist coastal communities in mitigating future impacts of global warming.

Classic Maya bloodletting and the cultural evolution of religious rituals: quantifying patterns of variation in hieroglyphic texts.

PubMed

Munson, Jessica; Amati, Viviana; Collard, Mark; Macri, Martha J

2014-01-01

Religious rituals that are painful or highly stressful are hypothesized to be costly signs of commitment essential for the evolution of complex society. Yet few studies have investigated how such extreme ritual practices were culturally transmitted in past societies. Here, we report the first study to analyze temporal and spatial variation in bloodletting rituals recorded in Classic Maya (ca. 250-900 CE) hieroglyphic texts. We also identify the sociopolitical contexts most closely associated with these ancient recorded rituals. Sampling an extensive record of 2,480 hieroglyphic texts, this study identifies every recorded instance of the logographic sign for the word ch'ahb' that is associated with ritual bloodletting. We show that documented rituals exhibit low frequency whose occurrence cannot be predicted by spatial location. Conversely, network ties better capture the distribution of bloodletting rituals across the southern Maya region. Our results indicate that bloodletting rituals by Maya nobles were not uniformly recorded, but were typically documented in association with antagonistic statements and may have signaled royal commitments among connected polities.

Classic Maya Bloodletting and the Cultural Evolution of Religious Rituals: Quantifying Patterns of Variation in Hieroglyphic Texts

PubMed Central

Munson, Jessica; Amati, Viviana; Collard, Mark; Macri, Martha J.

2014-01-01

Religious rituals that are painful or highly stressful are hypothesized to be costly signs of commitment essential for the evolution of complex society. Yet few studies have investigated how such extreme ritual practices were culturally transmitted in past societies. Here, we report the first study to analyze temporal and spatial variation in bloodletting rituals recorded in Classic Maya (ca. 250–900 CE) hieroglyphic texts. We also identify the sociopolitical contexts most closely associated with these ancient recorded rituals. Sampling an extensive record of 2,480 hieroglyphic texts, this study identifies every recorded instance of the logographic sign for the word ch’ahb’ that is associated with ritual bloodletting. We show that documented rituals exhibit low frequency whose occurrence cannot be predicted by spatial location. Conversely, network ties better capture the distribution of bloodletting rituals across the southern Maya region. Our results indicate that bloodletting rituals by Maya nobles were not uniformly recorded, but were typically documented in association with antagonistic statements and may have signaled royal commitments among connected polities. PMID:25254359

Explorer of Enceladus and Titan (E2T): Investigating ocean worlds' evolution and habitability in the solar system

NASA Astrophysics Data System (ADS)

Mitri, Giuseppe; Postberg, Frank; Soderblom, Jason M.; Wurz, Peter; Tortora, Paolo; Abel, Bernd; Barnes, Jason W.; Berga, Marco; Carrasco, Nathalie; Coustenis, Athena; Paul de Vera, Jean Pierre; D'Ottavio, Andrea; Ferri, Francesca; Hayes, Alexander G.; Hayne, Paul O.; Hillier, Jon K.; Kempf, Sascha; Lebreton, Jean-Pierre; Lorenz, Ralph D.; Martelli, Andrea; Orosei, Roberto; Petropoulos, Anastassios E.; Reh, Kim; Schmidt, Juergen; Sotin, Christophe; Srama, Ralf; Tobie, Gabriel; Vorburger, Audrey; Vuitton, Véronique; Wong, Andre; Zannoni, Marco

2018-06-01

Titan, with its organically rich and dynamic atmosphere and geology, and Enceladus, with its active plume, both harbouring global subsurface oceans, are prime environments in which to investigate the habitability of ocean worlds and the conditions for the emergence of life. We present a space mission concept, the Explorer of Enceladus and Titan (E2T), which is dedicated to investigating the evolution and habitability of these Saturnian satellites. E2T is proposed as a medium-class mission led by ESA in collaboration with NASA in response to ESA's M5 Cosmic Vision Call. E2T proposes a focused payload that would provide in-situ composition investigations and high-resolution imaging during multiple flybys of Enceladus and Titan using a solar-electric powered spacecraft in orbit around Saturn. The E2T mission would provide high-resolution mass spectrometry of the plume currently emanating from Enceladus' south polar terrain and of Titan's changing upper atmosphere. In addition, high-resolution infrared (IR) imaging would detail Titan's geomorphology at 50-100 m resolution and the temperature of the fractures on Enceladus' south polar terrain at meter resolution. These combined measurements of both Titan and Enceladus would enable the E2T mission scenario to achieve two major scientific goals: 1) Study the origin and evolution of volatile-rich ocean worlds; and 2) Explore the habitability and potential for life in ocean worlds. E2T's two high-resolution time-of-flight mass spectrometers would enable resolution of the ambiguities in chemical analysis left by the NASA/ESA/ASI Cassini-Huygens mission regarding the identification of low-mass organic species, detect high-mass organic species for the first time, further constrain trace species such as the noble gases, and clarify the evolution of solid and volatile species. The high-resolution IR camera would reveal the geology of Titan's surface and the energy dissipated by Enceladus' fractured south polar terrain and plume in detail unattainable by the Cassini mission.

Rattlesnake envenomation in 12 New World camelids.

PubMed

Dykgraaf, Susanne; Pusterla, Nicola; Van Hoogmoed, Linda M

2006-01-01

Rattlesnake envenomation of New World camelids is a seasonal problem with often dramatic clinical signs. The purpose of this study was to identify the clinical signs, laboratory results, treatment methods, and outcome for rattlesnake envenomation in New World camelids. Medical records from 1988 to 2004 were searched for New World camelids presented for rattlesnake bite or clinical signs suspected to be related to recent envenomation. Twelve records were identified. From these records a retrospective study was performed. Nine camelids presented for acute disease (2/9 arrived dead), whereas 3 presented for subacute onset of disease. Swelling of the lips, head and neck, tachypnea, dyspnea, tachycardia, and lethargy were the most common presenting signs. Snake bites were most commonly located to the muzzle (10/12). Common complete blood count (CBC) and serum biochemical abnormalities were neutrophilia, lymphopenia, increased muscle enzyme activity, hypoalbuminemia, hyperglycemia, hypokalemia, and thrombocytopenia. Treatment included combinations of intravenous fluid therapy, antimicrobials, anti-inflammatory drugs, tetanus prophylaxis, tracheostomy, supplemental oxygen, antivenom, total parenteral nutrition, and nursing care. Five of the 10 animals with acute onset of clinical signs survived, and all animals with subacute presentation died. The mortality rate for New World camelids with severe local tissue reaction and systemic signs of envenomation was 58%. New World camelids that sustain rattlesnake envenomation and severe facial swelling precluding prehension and mastication have a guarded prognosis for survival. Aggressive treatment is recommended to optimize the chances of survival. Animals with less severe local tissue reaction and absence of systemic signs have a better prognosis.

Pulmonary hypertension: Real-world data from a Portuguese expert referral centre.

PubMed

Gomes, A; Cruz, C; Rocha, J; Ricardo, M; Vicente, M; Melo, A; Santos, M; Carvalho, L; Gonçalves, F; Reis, A

2018-04-16

Pulmonary hypertension (PH) is a heterogeneous, debilitating condition with highly relevant impact on functional capacity, quality of life, and life-expectancy. This study aims to provide long-term data on the Portuguese PH population, by characterising the clinical presentation, evolution, and outcomes of PH patients in a specialised referral centre. Retrospective analysis of a cohort of 101 patients with pre-capillary PH (pcPH) referenced to an expert tertiary care referral centre in northern Portugal from 2002 to 2013. Diagnosis was confirmed by right heart catheterisation (RHC). PH classification followed consensus criteria from the 5th World Symposium in Nice, 2013. The most frequent causes of pcPH were Group 1 PH - pulmonary arterial hypertension (PAH) (54.4%) and Group 4 PH - Chronic thromboembolic pulmonary hypertension (CTEPH) (25.7%); importantly, 17.8% of patients presented PH associated with multiple aetiologies. Targeted therapy was used in 91.1% of patients (48.5% combination therapy). 1-, 3-, and 5-year survival was estimated at 86.6%, 76.7%, and 64.1%, respectively. Survival was significantly better for those ≤40 years old (10.5 vs. 6.4 years; P=0.003) and for women with I/HPAH (9.3 vs. 4.5 years; P=0.039). This study provides long-term, real-world data for the management of PAH and CTEPH in Portugal and demonstrates the importance of dedicated electronic medical records and well defined clinical management protocols for better patient outcomes. Patients presented mostly with intermediate or high risk of mortality, which suggests delayed diagnosis and highlights the need to increase awareness among clinicians. Copyright © 2018 Sociedade Portuguesa de Pneumologia. Published by Elsevier España, S.L.U. All rights reserved.

The search for understanding: the role of paradigms.

PubMed

Kelly, Marcella; Dowling, Maura; Millar, Michelle

2018-03-16

Kuhn's ( 1962 ) acknowledgement of a paradigm as a way that scientists make sense of their world and its reality gave recognition to the idea of 'paradigm shift'. This shift exposes the transience of paradigm development shaped by societal and scientific evolution. This ongoing evolutionary development provides the researcher with many paradigms to consider regarding how research is undertaken and the search for understanding achieved. An understanding of paradigm development is necessary when planning a study and can shape the search for understanding. It is hoped that the discussion presented here will assist novice and experienced researchers in articulating the rationales for their paradigm choices. An overview of the dominant paradigms is presented, reflecting ongoing paradigm development shaped by ontological, epistemological and methodological perspectives. Potential paradigm choices that shape research aims, objectives and focus in the search for understanding are considered. The inherent debates about paradigm shift, division, war and synthesis leave the researcher many perspectives to consider. Articulating the world views underpinning constructivism, interpretivism and pragmatism is particularly challenging because of the blurring of boundaries between them. The evolutionary nature of paradigmatic development has provided nurse researchers with the opportunity for methodological openness to the myriad research approaches, methods and designs that they may choose to answer their research question. However, it is imperative that researchers consider their ontological stances and the nature of their research questions. This is challenging in constructivism, interpretivism and pragmatism, where there is often an overlap of paradigm world views. ©2018 RCN Publishing Company Ltd. All rights reserved. Not to be copied, transmitted or recorded in any way, in whole or part, without prior permission of the publishers.

A synthesis of Plio-Pleistocene leaf wax biomarker records of hydrological variation in East Africa and their relationship with hominin evolution

NASA Astrophysics Data System (ADS)

Lupien, R.; Russell, J. M.; Campisano, C. J.; Feibel, C. S.; Deino, A. L.; Kingston, J.; Potts, R.; Cohen, A. S.

2017-12-01

Climate change is thought to play a critical role in human evolution. However, the mechanisms behind this relationship are difficult to test due to a lack of long, high-quality paleoclimate records from hominin fossil locales. We improve the understanding of this relationship by examining Plio-Pleistocene lake sediment cores from East Africa that were drilled by the Hominin Sites and Paleolakes Drilling Project, an international effort to study the environment in which our hominin ancestors evolved and dispersed. We have analyzed organic geochemical signals of climate from drill cores from Ethiopia and Kenya spanning the Pliocene to recent time (from north to south: paleolake Hadar, Lake Turkana, Lake Baringo, and paleolake Koora). Specifically, we analyzed the hydrogen isotopic composition of terrestrial leaf waxes, which records changes in regional atmospheric circulation and hydrology. We reconstructed quantitative records of rainfall amount at each of the study sites, which host sediment spanning different geologic times and regions. By compiling these records, we test hominin evolutionary hypotheses as well as crucial questions about climate trend and variability. We find that there is a gradual or step-wise enrichment in δDwax, signifying a trend from a wet to dry climate, from the Pliocene to the Pleistocene, perhaps implying an influence of global temperature, ice sheet extent, and/or atmospheric greenhouse gas concentrations on East African climate. However, the shift is small relative to the amplitude of orbital-scale isotopic variations. The records indicate a strong influence of eccentricity-modulated orbital precession, and imply that local insolation effects are the likely cause of East African precipitation. Several of the intervals of high isotopic variability coincide with key hominin fossil or technological transitions, suggesting that climate variability plays a key role in hominin evolution.

Exploring the Unknown

NASA Technical Reports Server (NTRS)

Logsdon, John M. (Editor); Garber, Stephen J. (Editor); Launius, Roger D. (Editor)

2004-01-01

One of the most important developments of the twentieth century has been the movement of humanity into space with machines and people. The extension of human activity into outer space has been accompanied by a high degree of self-awareness of its historical significance. Because most of the activity in outer space was carried out under government sponsorship, it was accompanied by the documentary record required of public institutions, and there has been a spate of official and privately written histories of most major aspects of space achievement to date. When top leaders considered what course of action to pursue in space, their deliberations and decisions often were carefully put on the record. There is, accordingly, no lack of material for those who aspire to understand the origins and evolution of U.S. space policies and programs.This reality forms the rationale for this series. Precisely because there is so much historical material available on space matters, the National Aeronautics and Space Administration (NASA) decided in 1988 that it would be extremely useful to have easily available to scholars and the interested public a selective collection of many of the seminal documents related to the evolution of the U.S. civilian space program. While recognizing that much space activity has taken place under the sponsorship of the Department of Defense and other national security organizations, the U.S. private sector, and in other countries around the world, NASA felt that there would be lasting value in a collection of documentary material primarily focused on the evolution of the U.S. government s civilian space program, most of which has been carried out since 1958 under the Agency s auspices. As a result, the NASA History Office contracted with the Space Policy Institute of George Washington University's Elliott School of International Affairs to prepare such a collection. This is the sixth volume in the documentary history series; two additional ones containing documents and introductory essays related to human space flight, including microgravity research in Earth orbit, will follow. The documents collected during this research project were assembled from a diverse number of both public and private sources. A major repository of primary source materials relative to the history of the civil space program is the NASA Historical Reference Collection of the NASA History Office located at the Agency s Headquarters in Washington, DC.

Maritime strategy and the nuclear age: Second edition

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

Till, G.

1984-01-01

This book offers an examination of the issues and theories that underlie contemporary maritime strategy. The author provides a description of the historical evolution of maritime strategy including an analysis of the works of Mahan, Columb and Corbett; assesses the impact that current political, technological and legal developments will have on the world's navies; and discusses contemporary American and Soviet maritime theory citing practical examples from recent naval events world-wide.

Thermal evolution of the western South Atlantic and the adjacent continent during Termination 1

NASA Astrophysics Data System (ADS)

Chiessi, C. M.; Mulitza, S.; Mollenhauer, G.; Silva, J. B.; Groeneveld, J.; Prange, M.

2015-06-01

During Termination 1, millennial-scale weakening events of the Atlantic meridional overturning circulation (AMOC) supposedly produced major changes in sea surface temperatures (SSTs) of the western South Atlantic, and in mean air temperatures (MATs) over southeastern South America. It has been suggested, for instance, that the Brazil Current (BC) would strengthen (weaken) and the North Brazil Current (NBC) would weaken (strengthen) during slowdown (speed-up) events of the AMOC. This anti-phase pattern was claimed to be a necessary response to the decreased North Atlantic heat piracy during periods of weak AMOC. However, the thermal evolution of the western South Atlantic and the adjacent continent is so far largely unknown. Here we address this issue, presenting high-temporal-resolution SST and MAT records from the BC and southeastern South America, respectively. We identify a warming in the western South Atlantic during Heinrich Stadial 1 (HS1), which is followed first by a drop and then by increasing temperatures during the Bølling-Allerød, in phase with an existing SST record from the NBC. Additionally, a similar SST evolution is shown by a southernmost eastern South Atlantic record, suggesting a South Atlantic-wide pattern in SST evolution during most of Termination 1. Over southeastern South America, our MAT record shows a two-step increase during Termination 1, synchronous with atmospheric CO2 rise (i.e., during the second half of HS1 and during the Younger Dryas), and lagging abrupt SST changes by several thousand years. This delay corroborates the notion that the long duration of HS1 was fundamental in driving the Earth out of the last glacial.

The Moon as a Recorder of Organic Evolution in the Early Solar System: A Lunar Regolith Analog Study

PubMed Central

Court, Richard W.; Crawford, Ian A.; Jones, Adrian P.; Joy, Katherine H.; Sephton, Mark A.

2015-01-01

Abstract The organic record of Earth older than ∼3.8 Ga has been effectively erased. Some insight is provided to us by meteorites as well as remote and direct observations of asteroids and comets left over from the formation of the Solar System. These primitive objects provide a record of early chemical evolution and a sample of material that has been delivered to Earth's surface throughout the past 4.5 billion years. Yet an effective chronicle of organic evolution on all Solar System objects, including that on planetary surfaces, is more difficult to find. Fortunately, early Earth would not have been the only recipient of organic matter–containing objects in the early Solar System. For example, a recently proposed model suggests the possibility that volatiles, including organic material, remain archived in buried paleoregolith deposits intercalated with lava flows on the Moon. Where asteroids and comets allow the study of processes before planet formation, the lunar record could extend that chronicle to early biological evolution on the planets. In this study, we use selected free and polymeric organic materials to assess the hypothesis that organic matter can survive the effects of heating in the lunar regolith by overlying lava flows. Results indicate that the presence of lunar regolith simulant appears to promote polymerization and, therefore, preservation of organic matter. Once polymerized, the mineral-hosted newly formed organic network is relatively protected from further thermal degradation. Our findings reveal the thermal conditions under which preservation of organic matter on the Moon is viable. Key Words: Moon—Regolith—Organic preservation—Biomarkers. Astrobiology 15, 154–168. PMID:25615648

The tempo and mode of New World monkey evolution and biogeography in the context of phylogenomic analysis.

PubMed

Jameson Kiesling, Natalie M; Yi, Soojin V; Xu, Ke; Gianluca Sperone, F; Wildman, Derek E

2015-01-01

The development and evolution of organisms is heavily influenced by their environment. Thus, understanding the historical biogeography of taxa can provide insights into their evolutionary history, adaptations and trade-offs realized throughout time. In the present study we have taken a phylogenomic approach to infer New World monkey phylogeny, upon which we have reconstructed the biogeographic history of extant platyrrhines. In order to generate sufficient phylogenetic signal within the New World monkey clade, we carried out a large-scale phylogenetic analysis of approximately 40 kb of non-genic genomic DNA sequence in a 36 species subset of extant New World monkeys. Maximum parsimony, maximum likelihood and Bayesian inference analysis all converged on a single optimal tree topology. Divergence dating and biogeographic analysis reconstruct the timing and geographic location of divergence events. The ancestral area reconstruction describes the geographic locations of the last common ancestor of extant platyrrhines and provides insight into key biogeographic events occurring during platyrrhine diversification. Through these analyses we conclude that the diversification of the platyrrhines took place concurrently with the establishment and diversification of the Amazon rainforest. This suggests that an expanding rainforest environment rather than geographic isolation drove platyrrhine diversification. Copyright © 2014 Elsevier Inc. All rights reserved.

The adaptive value of primate color vision for predator detection.

PubMed

Pessoa, Daniel Marques Almeida; Maia, Rafael; de Albuquerque Ajuz, Rafael Cavalcanti; De Moraes, Pedro Zurvaino Palmeira Melo Rosa; Spyrides, Maria Helena Constantino; Pessoa, Valdir Filgueiras

2014-08-01

The complex evolution of primate color vision has puzzled biologists for decades. Primates are the only eutherian mammals that evolved an enhanced capacity for discriminating colors in the green-red part of the spectrum (trichromatism). However, while Old World primates present three types of cone pigments and are routinely trichromatic, most New World primates exhibit a color vision polymorphism, characterized by the occurrence of trichromatic and dichromatic females and obligatory dichromatic males. Even though this has stimulated a prolific line of inquiry, the selective forces and relative benefits influencing color vision evolution in primates are still under debate, with current explanations focusing almost exclusively at the advantages in finding food and detecting socio-sexual signals. Here, we evaluate a previously untested possibility, the adaptive value of primate color vision for predator detection. By combining color vision modeling data on New World and Old World primates, as well as behavioral information from human subjects, we demonstrate that primates exhibiting better color discrimination (trichromats) excel those displaying poorer color visions (dichromats) at detecting carnivoran predators against the green foliage background. The distribution of color vision found in extant anthropoid primates agrees with our results, and may be explained by the advantages of trichromats and dichromats in detecting predators and insects, respectively. © 2014 Wiley Periodicals, Inc.

The Living Cosmos

NASA Astrophysics Data System (ADS)

Impey, Chris

2011-06-01

Preface; 1. The unfinished revolution; 2. Life's origins; 3. Extreme life; 4. Shaping evolution; 5. Living in the Solar System; 6. Distant worlds; 7. Are we alone?; Notes; Glossary; Reading list; Media resources; Illustration credits; Index.

How Good is the Fossil Record?

ERIC Educational Resources Information Center

Boucot, A. J.

1983-01-01

Suggests that earth scientists become active in the creationist debate by making sure that the religious concept creationism is not taught in schools and that well-based, informative material about organic evolution, earth's age, and nature of stratigraphic record are employed by science teachers. (Author/JN)

Complex response of a midcontinent north America drainage system to late Wisconsinan sedimentation

USGS Publications Warehouse

Bettis, E. Arthur; Autin, W.J.

1997-01-01

The geomorphic evolution of Mud Creek basin in eastern Iowa, U.S.A. serves to illustrate how geomorphic influences such as sediment supply, valley gradient, climate, and vegetation are recorded in the alluvial stratigraphic record. Sediment supply to the fluvial system increased significantly during the late Wisconsinan through a combination of periglacial erosion and loess accumulation. Subsequent evolution of the Holocene alluvial stratigraphic record reflects long-term routing of the late Wisconsinan sediment through the drainage basin in a series of cut-and-fill cycles whose timing was influenced by hydrologic response to change in climate and vegetation. When viewed in a regional context, the alluvial stratigraphic record appears to reflect a long-term complex response of the fluvial system to increased sediment supply during the late Wisconsinan. Hydrologic and sediment-supply changes accompanying the spread of Euroamerican agriculture to the basin in the 180Os dramatically upset trends in sedimentation and channel behavior established during the Holocene. Copyright ?? 1997, SEPM (Society for Sedimentary Geology).

Evolution of seahorses' upright posture was linked to Oligocene expansion of seagrass habitats.

PubMed

Teske, Peter R; Beheregaray, Luciano B

2009-08-23

Seahorses (Syngnathidae: Hippocampus) are iconic marine teleosts that are readily identifiable by their upright posture. The fossil record is inadequate to shed light on the evolution of this trait because it lacks transitional forms. There are, however, extant syngnathid species (the pygmy pipehorses) that look like horizontally swimming seahorses and that might represent a surviving evolutionary link between the benthic seahorses and other, free-swimming members of the family Syngnathidae. Using sequence data from five nuclear loci, we confirm the sister taxon relationship between seahorses and pygmy pipehorses. Molecular dating indicates that the two taxa diverged during the Late Oligocene. During this time, tectonic events in the Indo-West Pacific resulted in the formation of vast amounts of new shallow-water areas and associated expansion of seagrass habitats that would have favoured the seahorses' upright posture by improving their camouflage while not affecting their manoeuvrability negatively. The molecular techniques employed here provide new insights into the evolution of a taxon whose fossil record is incomplete, but whose evolutionary history is so recent that the major stages of morphological evolution are still represented in extant species.

Rates of climatic niche evolution are correlated with species richness in a large and ecologically diverse radiation of songbirds.

PubMed

Title, Pascal O; Burns, Kevin J

2015-05-01

By employing a recently inferred phylogeny and museum occurrence records, we examine the relationship of ecological niche evolution to diversification in the largest family of songbirds, the tanagers (Thraupidae). We test whether differences in species numbers in the major clades of tanagers can be explained by differences in rate of climatic niche evolution. We develop a methodological pipeline to process and filter occurrence records. We find that, of the ecological variables examined, clade richness is higher in clades with higher climatic niche rate, and that this rate is also greater for clades that occupy a greater extent of climatic space. Additionally, we find that more speciose clades contain species with narrower niche breadths, suggesting that clades in which species are more successful at diversifying across climatic gradients have greater potential for speciation or are more buffered from the risk of extinction. © 2015 John Wiley & Sons Ltd/CNRS.

Sensitivity of geomagnetic reversal rate on core evolution from numerical dynamos

NASA Astrophysics Data System (ADS)

Driscoll, P. E.; Davies, C. J.

2017-12-01

The paleomagnetic record indicates the geodynamo has evolved from frequently reversing to non-reversing (superchron) magnetic states several times over the Phanerozoic. Previous theoretical studies demonstrated a positive correlation between magnetic reversal rate and core-mantle boundary heat flux. However, attempts to identify such a correlation between reversal rates and proxies for internal cooling rate, such as plume events, superchron cycles, and subduction rates, have been inconclusive. Here we revisit the magnetic reversal occurrence rate in numerical dynamos at low Ekman numbers (faster rotation) and high magnetic Prandtl numbers (ratio of viscous and magnetic diffusivities). We focus on how the correlation between reversal rate and convective power depends on the core evolution rate and on other factors, such as Ek, Pm, and thermal boundary conditions. We apply our results to the seafloor reversal record in an attempt to infer the energetic evolution of the lower mantle and core over that period.

Earth science: Extraordinary world

NASA Astrophysics Data System (ADS)

Day, James M. D.

2016-09-01

The isotopic compositions of objects that formed early in the evolution of the Solar System have been found to be similar to Earth's composition -- overturning notions of our planet's chemical distinctiveness. See Letters p.394 & p.399

Acoustic signals of baby black caimans.

PubMed

Vergne, Amélie L; Aubin, Thierry; Taylor, Peter; Mathevon, Nicolas

2011-12-01

In spite of the importance of crocodilian vocalizations for the understanding of the evolution of sound communication in Archosauria and due to the small number of experimental investigations, information concerning the vocal world of crocodilians is limited. By studying black caimans Melanosuchus niger in their natural habitat, here we supply the experimental evidence that juvenile crocodilians can use a graded sound system in order to elicit adapted behavioral responses from their mother and siblings. By analyzing the acoustic structure of calls emitted in two different situations ('undisturbed context', during which spontaneous calls of juvenile caimans were recorded without perturbing the group, and a simulated 'predator attack', during which calls were recorded while shaking juveniles) and by testing their biological relevance through playback experiments, we reveal the existence of two functionally different types of juvenile calls that produce a different response from the mother and other siblings. Young black caimans can thus modulate the structure of their vocalizations along an acoustic continuum as a function of the emission context. Playback experiments show that both mother and juveniles discriminate between these 'distress' and 'contact' calls. Acoustic communication is thus an important component mediating relationships within family groups in caimans as it is in birds, their archosaurian relatives. Although probably limited, the vocal repertoire of young crocodilians is capable of transmitting the information necessary for allowing siblings and mother to modulate their behavior. Copyright © 2011 Elsevier GmbH. All rights reserved.

The dawn of the RNA World: Toward functional complexity through ligation of random RNA oligomers

PubMed Central

Briones, Carlos; Stich, Michael; Manrubia, Susanna C.

2009-01-01

A main unsolved problem in the RNA World scenario for the origin of life is how a template-dependent RNA polymerase ribozyme emerged from short RNA oligomers obtained by random polymerization on mineral surfaces. A number of computational studies have shown that the structural repertoire yielded by that process is dominated by topologically simple structures, notably hairpin-like ones. A fraction of these could display RNA ligase activity and catalyze the assembly of larger, eventually functional RNA molecules retaining their previous modular structure: molecular complexity increases but template replication is absent. This allows us to build up a stepwise model of ligation-based, modular evolution that could pave the way to the emergence of a ribozyme with RNA replicase activity, step at which information-driven Darwinian evolution would be triggered. PMID:19318464

The evolutionary history of Mimosa (Leguminosae): toward a phylogeny of the sensitive plants.

PubMed

Simon, Marcelo F; Grether, Rosaura; de Queiroz, Luciano P; Särkinen, Tiina E; Dutra, Valquíria F; Hughes, Colin E

2011-07-01

Large genera provide remarkable opportunities to investigate patterns of morphological evolution and historical biogeography in plants. A molecular phylogeny of the species-rich and morphologically and ecologically diverse genus Mimosa was generated to evaluate its infrageneric classification, reconstruct the evolution of a set of morphological characters, and establish the relationships of Old World species to the rest of the genus. We used trnD-trnT plastid sequences for 259 species of Mimosa (ca. 50% of the total) to reconstruct the phylogeny of the genus. Six morphological characters (petiolar nectary, inflorescence type, number of stamens, number of petals, pollen type, and seismonasty) were optimized onto the molecular tree. Mimosa was recovered as a monophyletic clade nested within the Piptadenia group and includes the former members of Schrankia, corroborating transfer of that genus to Mimosa. Although we found good support for several infrageneric groups, only one section (Mimadenia) was recovered as monophyletic. All but one of the morphological characters analyzed showed high levels of homoplasy. High levels of geographic structure were found, with species from the same area tending to group together in the phylogeny. Old World species of Mimosa form a monophyletic clade deeply nested within New World groups, indicating recent (6-10 Ma) long-distance dispersal. Although based on a single plastid region, our results establish a preliminary phylogenetic framework for Mimosa that can be used to infer patterns of morphological evolution and relationships and which provides pointers toward a revised infrageneric classification.

Niche conservatism and the invasive potential of the wild boar.

PubMed

Sales, Lilian Patrícia; Ribeiro, Bruno R; Hayward, Matt Warrington; Paglia, Adriano; Passamani, Marcelo; Loyola, Rafael

2017-09-01

Niche conservatism, i.e. the retention of a species' fundamental niche through evolutionary time, is cornerstone for biological invasion assessments. The fact that species tend to maintain their original climate niche allows predictive maps of invasion risk to anticipate potential invadable areas. Unravelling the mechanisms driving niche shifts can shed light on the management of invasive species. Here, we assessed niche shifts in one of the world's worst invasive species: the wild boar Sus scrofa. We also predicted potential invadable areas based on an ensemble of three ecological niche modelling methods, and evaluated the performance of models calibrated with native vs. pooled (native plus invaded) species records. By disentangling the drivers of change on the exotic wild boar population's niches, we found strong evidence for niche conservatism during biological invasion. Ecological niche models calibrated with both native and pooled range records predicted convergent areas. Also, observed niche shifts are mostly explained by niche unfilling, i.e. there are unoccupied areas in the exotic range where climate is analogous to the native range. Niche unfilling is expected as result of recent colonization and ongoing dispersal, and was potentially stronger for the Neotropics, where a recent wave of introductions for pig-farming and game-hunting has led to high wild boar population growth rates. The invasive potential of wild boar in the Neotropics is probably higher than in other regions, which has profound management implications if we are to prevent their invasion into species-rich areas, such as Amazonia, coupled with expansion of African swine fever and possibly great economic losses. Although the originally Eurasian-wide distribution suggests a pre-adaptation to a wide array of climates, the wild boar world-wide invasion does not exhibit evidence of niche evolution. The invasive potential of the wild boar therefore probably lies on the reproductive, dietary and morphological characteristics of this species, coupled with behavioural thermoregulation. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

Historical development of world wide guided missiles

NASA Technical Reports Server (NTRS)

Spearman, M. L.

1978-01-01

This paper attempts to put in perspective the development of missiles from early history to present time. The influence of World War II in accelerating the development of guided missiles, particularly through German scientists, is discussed. The dispersion of German scientists to other countries and the coupling of their work with native talent to develop guided missiles is traced. Particular emphasis is placed on the evolution of the missile in the U.S. and the U.S.S.R. Since the Soviets possess what is probably the world's most complete array of dedicated missile system types, their known inventory is reviewed in some detail.

A world of cytochrome P450s

PubMed Central

Nelson, David R.

2013-01-01

The world we live in is a biosphere influenced by all organisms who inhabit it. It is also an ecology of genes, with some having rather startling effects. The premise put forth in this issue is cytochrome P450 is a significant player in the world around us. Life and the Earth itself would be visibly different and diminished without cytochrome P450s. The contributions to this issue range from evolution on the billion year scale to the colour of roses, from Darwin to Rachel Carson; all as seen through the lens of cytochrome P450. PMID:23297353

IODP Expedition 351 Lithostratigraphy: Volcaniclastic Record of Izu-Bonin-Mariana (IBM) Arc Initiation

NASA Astrophysics Data System (ADS)

Barth, A. P.; Brandl, P. A.; Li, H.; Hickey-Vargas, R.; Jiang, F.; Kanayama, K.; Kusano, Y.; Marsaglia, K. M.; McCarthy, A.; Meffre, S.; Savov, I. P.; Tepley, F. J., III; Yogodzinski, G. M.

2014-12-01

The destruction of lithospheric plates by subduction is a fundamentally important process leading to arc magmatism and the creation of continental crust, yet subduction initiation and early magmatic arc evolution remain poorly understood. For many arc systems, onset of arc volcanism and early evolution are obscured by metamorphism or the record is deeply buried; however, initial products of arc systems may be preserved in forearc and backarc sedimentary records. IODP Expedition 351 recovered this history from the dispersed ash and pyroclast record in the proximal rear-arc of the northern IBM system west of the Kyushu-Palau Ridge. Drilling at Site U1438 in the Amami Sankaku Basin recovered a thick volcaniclastic record of subduction initiation and the early evolution of the Izu-Bonin Arc. A 160-m thick section of Neogene sediment overlies 1.3 kilometers of Paleogene volcaniclastic rocks with andesitic average composition; this volcaniclastic section was deposited on mafic volcanic basement rocks. The thin upper sediment layer is primarily terrigenous, biogenic and volcaniclastic mud and ooze with interspersed ash layers. The underlying Eocene to Oligocene volcaniclastic rocks are 33% tuffaceous mudstone, 61% tuffaceous sandstone, and 6% conglomerate with volcanic and rare sedimentary clasts commonly up to pebble and rarely to cobble size. The clastic section is characterized by repetitive conglomerate and sandstone-dominated intervals with intervening mudstone-dominated intervals, reflecting waxing and waning of coarse arc-derived sediment inputs through time. Volcanic lithic clasts in sandstones and conglomerates range from basalt to rhyolite in composition and include well-preserved pumice, reflecting a lithologically diverse and compositionally variable arc volcanic source.

Evolution and extinction in the marine realm: some constraints imposed by phytoplankton

NASA Technical Reports Server (NTRS)

Knoll, A. H.

1989-01-01

The organic and mineralized remains of planktonic algae provide a rich record of microplankton evolution extending over nearly half of the preserved geological record. In general, Phanerozoic patterns of phytoplankton radiation and extinction parallel those documented for skeletonized marine invertebrates, both augmenting and constraining thought about evolution in the oceans. Rapidly increasing knowledge of Proterozoic plankton is making possible the recognition of additional episodes of diversification and extinction that antedate the Ediacaran radiation of macroscopic animals. In contrast to earlier phytoplankton history, the late Mesozoic and Cainozoic record is documented in sufficient detail to constrain theories of mass extinction in more than a general way. Broad patterns of diversity change in planktonic algae show similarities across the Cretaceous-Tertiary and Eocene-Oligocene boundaries, but detailed comparisons of origination and extinction rates in calcareous nannoplankton, as well as other algae and skeletonized protozoans, suggest that the two episodes were quite distinct. Common causation appears unlikely, casting doubt on monolithic theories of mass extinction, whether periodic or not. Studies of mass extinction highlight a broader class of insights that paleontologists can contribute to evolutionary biology: the evaluation of evolutionary change in the context of evolving Earth-surface environments.

Life and consciousness – The Vedāntic view

PubMed Central

Shanta, Bhakti Niskama

2015-01-01

In the past, philosophers, scientists, and even the general opinion, had no problem in accepting the existence of consciousness in the same way as the existence of the physical world. After the advent of Newtonian mechanics, science embraced a complete materialistic conception about reality. Scientists started proposing hypotheses like abiogenesis (origin of first life from accumulation of atoms and molecules) and the Big Bang theory (the explosion theory for explaining the origin of universe). How the universe came to be what it is now is a key philosophical question. The hypothesis that it came from Nothing (as proposed by Stephen Hawking, among others), proves to be dissembling, since the quantum vacuum can hardly be considered a void. In modern science, it is generally assumed that matter existed before the universe came to be. Modern science hypothesizes that the manifestation of life on Earth is nothing but a mere increment in the complexity of matter — and hence is an outcome of evolution of matter (chemical evolution) following the Big Bang. After the manifestation of life, modern science believed that chemical evolution transformed itself into biological evolution, which then had caused the entire biodiversity on our planet. The ontological view of the organism as a complex machine presumes life as just a chance occurrence, without any inner purpose. This approach in science leaves no room for the subjective aspect of consciousness in its attempt to know the world as the relationships among forces, atoms, and molecules. On the other hand, the Vedāntic view states that the origin of everything material and nonmaterial is sentient and absolute (unconditioned). Thus, sentient life is primitive and reproductive of itself – omne vivum ex vivo – life comes from life. This is the scientifically verified law of experience. Life is essentially cognitive and conscious. And, consciousness, which is fundamental, manifests itself in the gradational forms of all sentient and insentient nature. In contrast to the idea of objective evolution of bodies, as envisioned by Darwin and followers, Vedānta advocates the idea of subjective evolution of consciousness as the developing principle of the world. In this paper, an attempt has been made to highlight a few relevant developments supporting a sentient view of life in scientific research, which has caused a paradigm shift in our understanding of life and its origin. PMID:27066168

Life and consciousness - The Vedāntic view.

PubMed

Shanta, Bhakti Niskama

2015-01-01

In the past, philosophers, scientists, and even the general opinion, had no problem in accepting the existence of consciousness in the same way as the existence of the physical world. After the advent of Newtonian mechanics, science embraced a complete materialistic conception about reality. Scientists started proposing hypotheses like abiogenesis (origin of first life from accumulation of atoms and molecules) and the Big Bang theory (the explosion theory for explaining the origin of universe). How the universe came to be what it is now is a key philosophical question. The hypothesis that it came from Nothing (as proposed by Stephen Hawking, among others), proves to be dissembling, since the quantum vacuum can hardly be considered a void. In modern science, it is generally assumed that matter existed before the universe came to be. Modern science hypothesizes that the manifestation of life on Earth is nothing but a mere increment in the complexity of matter - and hence is an outcome of evolution of matter (chemical evolution) following the Big Bang. After the manifestation of life, modern science believed that chemical evolution transformed itself into biological evolution, which then had caused the entire biodiversity on our planet. The ontological view of the organism as a complex machine presumes life as just a chance occurrence, without any inner purpose. This approach in science leaves no room for the subjective aspect of consciousness in its attempt to know the world as the relationships among forces, atoms, and molecules. On the other hand, the Vedāntic view states that the origin of everything material and nonmaterial is sentient and absolute (unconditioned). Thus, sentient life is primitive and reproductive of itself - omne vivum ex vivo - life comes from life. This is the scientifically verified law of experience. Life is essentially cognitive and conscious. And, consciousness, which is fundamental, manifests itself in the gradational forms of all sentient and insentient nature. In contrast to the idea of objective evolution of bodies, as envisioned by Darwin and followers, Vedānta advocates the idea of subjective evolution of consciousness as the developing principle of the world. In this paper, an attempt has been made to highlight a few relevant developments supporting a sentient view of life in scientific research, which has caused a paradigm shift in our understanding of life and its origin.

Beyond Descartes and Newton: Recovering life and humanity.

PubMed

Kauffman, Stuart A; Gare, Arran

2015-12-01

Attempts to 'naturalize' phenomenology challenge both traditional phenomenology and traditional approaches to cognitive science. They challenge Edmund Husserl's rejection of naturalism and his attempt to establish phenomenology as a foundational transcendental discipline, and they challenge efforts to explain cognition through mainstream science. While appearing to be a retreat from the bold claims made for phenomenology, it is really its triumph. Naturalized phenomenology is spearheading a successful challenge to the heritage of Cartesian dualism. This converges with the reaction against Cartesian thought within science itself. Descartes divided the universe between res cogitans, thinking substances, and res extensa, the mechanical world. The latter won with Newton and we have, in most of objective science since, literally lost our mind, hence our humanity. Despite Darwin, biologists remain children of Newton, and dream of a grand theory that is epistemologically complete and would allow lawful entailment of the evolution of the biosphere. This dream is no longer tenable. We now have to recognize that science and scientists are within and part of the world we are striving to comprehend, as proponents of endophysics have argued, and that physics, biology and mathematics have to be reconceived accordingly. Interpreting quantum mechanics from this perspective is shown to both illuminate conscious experience and reveal new paths for its further development. In biology we must now justify the use of the word "function". As we shall see, we cannot prestate the ever new biological functions that arise and constitute the very phase space of evolution. Hence, we cannot mathematize the detailed becoming of the biosphere, nor write differential equations for functional variables we do not know ahead of time, nor integrate those equations, so no laws "entail" evolution. The dream of a grand theory fails. In place of entailing laws, a post-entailing law explanatory framework is proposed in which Actuals arise in evolution that constitute new boundary conditions that are enabling constraints that create new, typically unprestatable, Adjacent Possible opportunities for further evolution, in which new Actuals arise, in a persistent becoming. Evolution flows into a typically unprestatable succession of Adjacent Possibles. Given the concept of function, the concept of functional closure of an organism making a living in its world, becomes central. Implications for patterns in evolution include historical reconstruction, and statistical laws such as the distribution of extinction events, or species per genus, and the use of formal cause, not efficient cause, laws. Copyright © 2015. Published by Elsevier Ltd.

Evolution in Stage-Structured Populations

PubMed Central

Barfield, Michael; Holt, Robert D.; Gomulkiewicz, Richard

2016-01-01

For many organisms, stage is a better predictor of demographic rates than age. Yet no general theoretical framework exists for understanding or predicting evolution in stage-structured populations. Here, we provide a general modeling approach that can be used to predict evolution and demography of stage-structured populations. This advances our ability to understand evolution in stage-structured populations to a level previously available only for populations structured by age. We use this framework to provide the first rigorous proof that Lande’s theorem, which relates adaptive evolution to population growth, applies to stage-classified populations, assuming only normality and that evolution is slow relative to population dynamics. We extend this theorem to allow for different means or variances among stages. Our next major result is the formulation of Price’s theorem, a fundamental law of evolution, for stage-structured populations. In addition, we use data from Trillium grandiflorum to demonstrate how our models can be applied to a real-world population and thereby show their practical potential to generate accurate projections of evolutionary and population dynamics. Finally, we use our framework to compare rates of evolution in age- versus stage-structured populations, which shows how our methods can yield biological insights about evolution in stage-structured populations. PMID:21460563

Cryptic genetic variation: evolution's hidden substrate.

PubMed

Paaby, Annalise B; Rockman, Matthew V

2014-04-01

Cryptic genetic variation (CGV) is invisible under normal conditions, but it can fuel evolution when circumstances change. In theory, CGV can represent a massive cache of adaptive potential or a pool of deleterious alleles that are in need of constant suppression. CGV emerges from both neutral and selective processes, and it may inform about how human populations respond to change. CGV facilitates adaptation in experimental settings, but does it have an important role in the real world? Here, we review the empirical support for widespread CGV in natural populations, including its potential role in emerging human diseases and the growing evidence of its contribution to evolution.

What Is a Personal Health Record (PHR)?

MedlinePlus

... and critical step in the evolution of health information management ( HIM ). The book “ The Personal Health Record ” assists ... potential health conditions, treatment options, costs of treatment, management of chronic conditions, healthy lifestyle choices, preventive actions, and monitoring the ... Does a PHR Work? How Does a ...

Time rescaling and pattern formation in biological evolution.

PubMed

Igamberdiev, Abir U

2014-09-01

Biological evolution is analyzed as a process of continuous measurement in which biosystems interpret themselves in the environment resulting in changes of both. This leads to rescaling of internal time (heterochrony) followed by spatial reconstructions of morphology (heterotopy). The logical precondition of evolution is the incompleteness of biosystem's internal description, while the physical precondition is the uncertainty of quantum measurement. The process of evolution is based on perpetual changes in interpretation of information in the changing world. In this interpretation the external biospheric gradients are used for establishment of new features of organization. It is concluded that biological evolution involves the anticipatory epigenetic changes in the interpretation of genetic symbolism which cannot generally be forecasted but can provide canalization of structural transformations defined by the existing organization and leading to predictable patterns of form generation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Molecular Evolution of the Nuclear Factor (Erythroid-Derived 2)-Like 2 Gene Nrf2 in Old World Fruit Bats (Chiroptera: Pteropodidae).

PubMed

Yin, Qiuyuan; Zhu, Lei; Liu, Di; Irwin, David M; Zhang, Shuyi; Pan, Yi-Hsuan

2016-01-01

Mammals developed antioxidant systems to defend against oxidative damage in their daily life. Enzymatic antioxidants and low molecular weight antioxidants (LMWAs) constitute major parts of the antioxidant systems. Nuclear factor (erythroid-derived 2)-like 2 (Nrf2, encoded by the Nrf2 gene) is a central transcriptional regulator, regulating transcription, of many antioxidant enzymes. Frugivorous bats eat large amounts of fruits that contain high levels of LMWAs such as vitamin C, thus, a reliance on LMWAs might greatly reduce the need for antioxidant enzymes in comparison to insectivorous bats. Therefore, it is possible that frugivorous bats have a reduced need for Nrf2 function due to their substantial intake of diet-antioxidants. To test whether the Nrf2 gene has undergone relaxed evolution in fruit-eating bats, we obtained Nrf2 sequences from 16 species of bats, including four Old World fruit bats (Pteropodidae) and one New World fruit bat (Phyllostomidae). Our molecular evolutionary analyses revealed changes in the selection pressure acting on Nrf2 gene and identified seven specific amino acid substitutions that occurred on the ancestral lineage leading to Old World fruit bats. Biochemical experiments were conducted to examine Nrf2 in Old World fruit bats and showed that the amount of catalase, which is regulated by Nrf2, was significantly lower in the brain, heart and liver of Old World fruit bats despite higher levels of Nrf2 protein in Old World fruit bats. Computational predictions suggest that three of these seven amino acid replacements might be deleterious to Nrf2 function. Therefore, the results suggest that Nrf2 gene might have experienced relaxed constraint in Old World fruit bats, however, we cannot rule out the possibility of positive selection. Our study provides the first data on the molecular adaptation of Nrf2 gene in frugivorous bats in compensation to the increased levels of LWMAs from their fruit-diet.

Molecular Evolution of the Nuclear Factor (Erythroid-Derived 2)-Like 2 Gene Nrf2 in Old World Fruit Bats (Chiroptera: Pteropodidae)

PubMed Central

Liu, Di; Irwin, David M.; Zhang, Shuyi; Pan, Yi-Hsuan

2016-01-01

Mammals developed antioxidant systems to defend against oxidative damage in their daily life. Enzymatic antioxidants and low molecular weight antioxidants (LMWAs) constitute major parts of the antioxidant systems. Nuclear factor (erythroid-derived 2)-like 2 (Nrf2, encoded by the Nrf2 gene) is a central transcriptional regulator, regulating transcription, of many antioxidant enzymes. Frugivorous bats eat large amounts of fruits that contain high levels of LMWAs such as vitamin C, thus, a reliance on LMWAs might greatly reduce the need for antioxidant enzymes in comparison to insectivorous bats. Therefore, it is possible that frugivorous bats have a reduced need for Nrf2 function due to their substantial intake of diet-antioxidants. To test whether the Nrf2 gene has undergone relaxed evolution in fruit-eating bats, we obtained Nrf2 sequences from 16 species of bats, including four Old World fruit bats (Pteropodidae) and one New World fruit bat (Phyllostomidae). Our molecular evolutionary analyses revealed changes in the selection pressure acting on Nrf2 gene and identified seven specific amino acid substitutions that occurred on the ancestral lineage leading to Old World fruit bats. Biochemical experiments were conducted to examine Nrf2 in Old World fruit bats and showed that the amount of catalase, which is regulated by Nrf2, was significantly lower in the brain, heart and liver of Old World fruit bats despite higher levels of Nrf2 protein in Old World fruit bats. Computational predictions suggest that three of these seven amino acid replacements might be deleterious to Nrf2 function. Therefore, the results suggest that Nrf2 gene might have experienced relaxed constraint in Old World fruit bats, however, we cannot rule out the possibility of positive selection. Our study provides the first data on the molecular adaptation of Nrf2 gene in frugivorous bats in compensation to the increased levels of LWMAs from their fruit-diet. PMID:26735303

Bridging the gap between the randomised clinical trial world and the real world by combination of population-based registry and electronic health record data: A case study in haemato-oncology.

PubMed

Kibbelaar, R E; Oortgiesen, B E; van der Wal-Oost, A M; Boslooper, K; Coebergh, J W; Veeger, N J G M; Joosten, P; Storm, H; van Roon, E N; Hoogendoorn, M

2017-11-01

Randomised clinical trials (RCTs) are considered the basis of evidence-based medicine. It is recognised more and more that application of RCT results in daily practice of clinical decision-making is limited because the RCT world does not correspond with the clinical real world. Recent strategies aiming at substitution of RCT databases by improved population-based registries (PBRs) or by improved electronic health record (EHR) systems to provide significant data for clinical science are discussed. A novel approach exemplified by the HemoBase haemato-oncology project is presented. In this approach, a PBR is combined with an advanced EHR, providing high-quality data for observational studies and support of best practice development. This PBR + EHR approach opens a perspective on randomised registry trials. Copyright © 2017 Elsevier Ltd. All rights reserved.

Storytelling in the digital world: achieving higher-level learning objectives.

PubMed

Schwartz, Melissa R

2012-01-01

Nursing students are not passive media consumers but instead live in a technology ecosystem where digital is the language they speak. To prepare the next generation of nurses, educators must incorporate multiple technologies to improve higher-order learning. The author discusses the evolution and use of storytelling as part of the digital world and how digital stories can be aligned with Bloom's Taxonomy so that students achieve higher-level learning objectives.

Variation, differential reproduction and oscillation: the evolution of nucleic acid hybridization.

PubMed

Suárez-Díaz, Edna

2013-01-01

This paper builds upon Hans-Jörg Rheinberger ideas on the oscillation and intercalation of epistemic things and technical objects in experimental systems, to give a fine-grained analysis of what here is called the problems of "adaptation" between our material and cognitive tools and the phenomena of the material world. To do so, it relies on the case-study of the evolution of nucleic acid hybridization and the stabilization of satellite DNA.

A novel dataset on legal traditions, their determinants, and their economic role in 155 transplants.

PubMed

Guerriero, Carmine

2016-09-01

The law and the economy are deeply influenced by the legal tradition or origin, which is the bundle of institutions shaping lawmaking and dispute adjudication. The two principal legal traditions, common law and civil law, have been transplanted through colonization and occupation to the vast majority of the jurisdictions in the world by a group of European countries. Here, I illustrate a novel dataset recording the lawmaking institution employed by 155 of these jurisdictions at independence and in 2000 and four discretion-curbing adjudication institutions adopted by 99 of these "transplants" at the same two points in time. Contrary to the "legal origins" scholars׳ assumption, 25 transplants changed the transplanted lawmaking institution and 95 modified at least one of the transplanted lawmaking and adjudication rules. In "Endogenous Legal Traditions" (Guerriero, 2016a) [12], I document that these reforms are consistent with a model of the design of legal institutions by societies heterogeneous in their endowment of both the extent of cultural heterogeneity and the quality of the political process. In "Endogenous Legal Traditions and Economic Outcomes" (Guerriero, 2016b) [13] moreover, I show the relevance of considering legal evolution and the endogeneity between legal traditions and economics outcomes. The data illustrated here also include the proxies for the determinants of legal evolution I use in "Endogenous Legal Traditions" (Guerriero, 2016a) [12] and the novel measure of economic outcomes I employ in "Endogenous Legal Traditions and Economic Outcomes" (Guerriero, 2016b) [13].

Evolution of large body size in abalones (Haliotis): Patterns and implications

USGS Publications Warehouse

Estes, J.A.; Lindberg, D.R.; Wray, C.

2005-01-01

Kelps and other fleshy macroalgae - dominant reef-inhabiting organisms in cool - seasmay have radiated extensively following late Cenozoic polar cooling, thus triggering a chain of evolutionary change in the trophic ecology of nearshore temperate ecosystems. We explore this hypothesis through an analysis of body size in the abalones (Gastropoda; Haliotidae), a widely distributed group in modern oceans that displays a broad range of body sizes and contains fossil representatives from the late Cretaceous (60-75 Ma). Geographic analysis of maximum shell length in living abalones showed that small-bodied species, while most common in the Tropics, have a cosmopolitan distribution, whereas large-bodied species occur exclusively in cold-water ecosystems dominated by kelps and other macroalgae. The phylogeography of body size evolution in extant abalones was assessed by constructing a molecular phylogeny in a mix of large and small species obtained from different regions of the world. This analysis demonstrates that small body size is the plesiomorphic state and largeness has likely arisen at least twice. Finally, we compiled data on shell length from the fossil record to determine how (slowly or suddenly) and when large body size arose in the abalones. These data indicate that large body size appears suddenly at the Miocene/Pliocene boundary. Our findings support the view that fleshy-algal dominated ecosystems radiated rapidly in the coastal oceans with the onset of the most recent glacial age. We conclude with a discussion of the broader implications of this change. ?? 2005 The Paleontological Society. All rights reserved.

Preceramic maize from Paredones and Huaca Prieta, Peru

PubMed Central

Grobman, Alexander; Bonavia, Duccio; Dillehay, Tom D.; Piperno, Dolores R.; Iriarte, José; Holst, Irene

2012-01-01

Maize (Zea mays ssp. mays) is among the world's most important and ancient domesticated crops. Although the chronology of its domestication and initial dispersals out of Mexico into Central and South America has become more clear due to molecular and multiproxy archaeobotanical research, important problems remain. Among them is the paucity of information on maize's early morphological evolution and racial diversification brought about in part by the poor preservation of macrofossils dating to the pre-5000 calibrated years before the present period from obligate dispersal routes located in the tropical forest. We report newly discovered macrobotanical and microbotanical remains of maize that shed significant light on the chronology, land race evolution, and cultural contexts associated with the crop's early movements into South America and adaptation to new environments. The evidence comes from the coastal Peruvian sites of Paredones and Huaca Prieta, Peru; dates from the middle and late preceramic and early ceramic periods (between ca. 6700 and 3000 calibrated years before the present); and constitutes some of the earliest known cobs, husks, stalks, and tassels. The macrobotanical record indicates that a diversity of racial complexes characteristic of the Andean region emerged during the preceramic era. In addition, accelerator mass spectrometry radiocarbon determinations carried out directly on different structures of preserved maize plants strongly suggest that assays on burned cobs are more reliable than those on unburned cobs. Our findings contribute to knowledge of the early diffusion of maize and agriculture and have broader implications for understanding the development of early preindustrial human societies. PMID:22307642

Preceramic maize from Paredones and Huaca Prieta, Peru.

PubMed

Grobman, Alexander; Bonavia, Duccio; Dillehay, Tom D; Piperno, Dolores R; Iriarte, José; Holst, Irene

2012-01-31

Maize (Zea mays ssp. mays) is among the world's most important and ancient domesticated crops. Although the chronology of its domestication and initial dispersals out of Mexico into Central and South America has become more clear due to molecular and multiproxy archaeobotanical research, important problems remain. Among them is the paucity of information on maize's early morphological evolution and racial diversification brought about in part by the poor preservation of macrofossils dating to the pre-5000 calibrated years before the present period from obligate dispersal routes located in the tropical forest. We report newly discovered macrobotanical and microbotanical remains of maize that shed significant light on the chronology, land race evolution, and cultural contexts associated with the crop's early movements into South America and adaptation to new environments. The evidence comes from the coastal Peruvian sites of Paredones and Huaca Prieta, Peru; dates from the middle and late preceramic and early ceramic periods (between ca. 6700 and 3000 calibrated years before the present); and constitutes some of the earliest known cobs, husks, stalks, and tassels. The macrobotanical record indicates that a diversity of racial complexes characteristic of the Andean region emerged during the preceramic era. In addition, accelerator mass spectrometry radiocarbon determinations carried out directly on different structures of preserved maize plants strongly suggest that assays on burned cobs are more reliable than those on unburned cobs. Our findings contribute to knowledge of the early diffusion of maize and agriculture and have broader implications for understanding the development of early preindustrial human societies.

Fantastic animals as an experimental model to teach animal adaptation

PubMed Central

Guidetti, Roberto; Baraldi, Laura; Calzolai, Caterina; Pini, Lorenza; Veronesi, Paola; Pederzoli, Aurora

2007-01-01

Background Science curricula and teachers should emphasize evolution in a manner commensurate with its importance as a unifying concept in science. The concept of adaptation represents a first step to understand the results of natural selection. We settled an experimental project of alternative didactic to improve knowledge of organism adaptation. Students were involved and stimulated in learning processes by creative activities. To set adaptation in a historic frame, fossil records as evidence of past life and evolution were considered. Results The experimental project is schematized in nine phases: review of previous knowledge; lesson on fossils; lesson on fantastic animals; planning an imaginary world; creation of an imaginary animal; revision of the imaginary animals; adaptations of real animals; adaptations of fossil animals; and public exposition. A rubric to evaluate the student's performances is reported. The project involved professors and students of the University of Modena and Reggio Emilia and of the "G. Marconi" Secondary School of First Degree (Modena, Italy). Conclusion The educational objectives of the project are in line with the National Indications of the Italian Ministry of Public Instruction: knowledge of the characteristics of living beings, the meanings of the term "adaptation", the meaning of fossils, the definition of ecosystem, and the particularity of the different biomes. At the end of the project, students will be able to grasp particular adaptations of real organisms and to deduce information about the environment in which the organism evolved. This project allows students to review previous knowledge and to form their personalities. PMID:17767729

Thermal emission before earthquakes by analyzing satellite infra-red data

NASA Astrophysics Data System (ADS)

Ouzounov, D.; Taylor, P.; Bryant, N.; Pulinets, S.; Freund, F.

2004-05-01

Satellite thermal imaging data indicate long-lived thermal anomaly fields associated with large linear structures and fault systems in the Earth's crust but also with short-lived anomalies prior to major earthquakes. Positive anomalous land surface temperature excursions of the order of 3-4oC have been observed from NOAA/AVHRR, GOES/METEOSAT and EOS Terra/Aqua satellites prior to some major earthquake around the world. The rapid time-dependent evolution of the "thermal anomaly" suggests that is changing mid-IR emissivity from the earth. These short-lived "thermal anomalies", however, are very transient therefore there origin has yet to be determined. Their areal extent and temporal evolution may be dependent on geology, tectonic, focal mechanism, meteorological conditions and other factors.This work addresses the relationship between tectonic stress, electro-chemical and thermodynamic processes in the atmosphere and increasing mid-IR flux as part of a larger family of electromagnetic (EM) phenomena related to seismic activity.We still need to understand better the link between seismo-mechanical processes in the crust, on the surface, and at the earth-atmospheric interface that trigger thermal anomalies. This work serves as an introduction to our effort to find an answer to this question. We will present examples from the strong earthquakes that have occurred in the Americas during 2003/2004 and the techniques used to record the thermal emission mid-IR anomalies, geomagnetic and ionospheric variations that appear to associated with impending earthquake activity.

Global biogeography and evolution of Cuvierina pteropods.

PubMed

Burridge, Alice K; Goetze, Erica; Raes, Niels; Huisman, Jef; Peijnenburg, Katja T C A

2015-03-12

Shelled pteropods are planktonic gastropods that are potentially good indicators of the effects of ocean acidification. They also have high potential for the study of zooplankton evolution because they are metazoan plankton with a good fossil record. We investigated phenotypic and genetic variation in pteropods belonging to the genus Cuvierina in relation to their biogeographic distribution across the world's oceans. We aimed to assess species boundaries and to reconstruct their evolutionary history. We distinguished six morphotypes based on geometric morphometric analyses of shells from 926 museum and 113 fresh specimens. These morphotypes have distinct geographic distributions across the Atlantic, Pacific and Indian oceans, and belong to three major genetic clades based on COI and 28S DNA sequence data. Using a fossil-calibrated phylogeny, we estimated that these clades separated in the Late Oligocene and Early to Middle Miocene. We found evidence for ecological differentiation among all morphotypes based on ecological niche modelling with sea surface temperature, salinity and phytoplankton biomass as primary determinants. Across all analyses, we found highly congruent patterns of differentiation suggesting species level divergences between morphotypes. However, we also found distinct morphotypes (e.g. in the Atlantic Ocean) that were ecologically, but not genetically differentiated. Given the distinct ecological and phenotypic specializations found among both described and undescribed Cuvierina taxa, they may not respond equally to future ocean changes and may not be equally sensitive to ocean acidification. Our findings support the view that ecological differentiation may be an important driving force in the speciation of zooplankton.

Entropy and charge in molecular evolution--the case of phosphate

NASA Technical Reports Server (NTRS)

Arrhenius, G.; Sales, B.; Mojzsis, S.; Lee, T.; Bada, J. L. (Principal Investigator)

1997-01-01

Biopoesis, the creation of life, implies molecular evolution from simple components, randomly distributed and in a dilute state, to form highly organized, concentrated systems capable of metabolism, replication and mutation. This chain of events must involve environmental processes that can locally lower entropy in several steps; by specific selection from an indiscriminate mixture, by concentration from dilute solution, and in the case of the mineral-induced processes, by particular effectiveness in ordering and selective reaction, directed toward formation of functional biomolecules. Numerous circumstances provide support for the notion that negatively charged molecules were functionally required and geochemically available for biopoesis. Sulfite ion may have been important in bisulfite complex formation with simple aldehydes, facilitating the initial concentration by sorption of aldehydes in positively charged surface active minerals. Borate ion may have played a similar, albeit less investigated role in forming charged sugar complexes. Among anionic species, oligophosphate ions and charged phosphate esters are likely to have been of even more wide ranging importance, reflected in the continued need for phosphate in a proposed RNA world, and extending its central role to evolved biochemistry. Phosphorylation is shown to result in selective concentration by surface sorption of compounds, otherwise too dilute to support condensation reactions. It provides protection against rapid hydrolysis of sugars and, by selective concentration, induces the oligomerization of aldehydes. As a manifestation of life arisen, phosphate already appears in an organic context in the oldest preserved sedimentary record.

A Novel Application of Synthetic Biology and Directed Evolution to Engineer Phage-based Antibiotics

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

Wu, Meiye

The emergence of multiple drug resistant bacteria poses threats to human health, agriculture and food safety. Annually over 100,000 deaths and up to $20 billion loss to the U.S. economy are attributed to multiple drug resistant bacteria. With only four new chemical antibiotics in the drug development pipeline, we are in dire need of new solutions to address the emerging threat of multiple drug resistance. We propose a paradigm-changing approach to address the multi-drug resistant bacteria problem by utilizing Synthetic Biology (SynBio) methodologies to create and evolve “designer” bacteriophages or phages – viruses that specifically infect bacteria – to infectmore » and kill newly emerging pathogenic bacterial strains WITHOUT the need for chemical antibiotics. A major advantage of using phage to combat pathogenic bacteria is that phages can co-evolve with their bacterial host, and Sandia can be the first in the world to establish an industrial scale Synthetic Biology pipeline for phage directed evolution for safe, targeted, customizable solution to bacterial drug resistance. Since there is no existing phage directed evolution effort within or outside of Sandia, this proposal is suitable as a high-risk LDRD effort to create the first pipeline for such an endeavor. The high potential reward nature of this proposal will be the immediate impact in decontamination and restoration of surfaces and infrastructure, with longer term impact in human or animal therapeutics. The synthetic biology and screening approaches will lead to fundamental knowledge of phage/bacteria co-evolution, making Sandia a world leader in directed evolution of bacteriophages.« less

Niche-tracking migrants and niche-switching residents: evolution of climatic niches in New World warblers (Parulidae)

PubMed Central

Gómez, Camila; Tenorio, Elkin A.; Montoya, Paola; Cadena, Carlos Daniel

2016-01-01

Differences in life-history traits between tropical and temperate lineages are often attributed to differences in their climatic niche dynamics. For example, the more frequent appearance of migratory behaviour in temperate-breeding species than in species originally breeding in the tropics is believed to have resulted partly from tropical climatic stability and niche conservatism constraining tropical species from shifting their ranges. However, little is known about the patterns and processes underlying climatic niche evolution in migrant and resident animals. We evaluated the evolution of overlap in climatic niches between seasons and its relationship to migratory behaviour in the Parulidae, a family of New World passerine birds. We used ordination methods to measure seasonal niche overlap and niche breadth of 54 resident and 49 migrant species and used phylogenetic comparative methods to assess patterns of climatic niche evolution. We found that despite travelling thousands of kilometres, migrants tracked climatic conditions across the year to a greater extent than tropical residents. Migrant species had wider niches than resident species, although residents as a group occupied a wider climatic space and niches of migrants and residents overlapped extensively. Neither breeding latitude nor migratory distance explained variation among species in climatic niche overlap between seasons. Our findings support the notion that tropical species have narrower niches than temperate-breeders, but does not necessarily constrain their ability to shift or expand their geographical ranges and become migratory. Overall, the tropics may have been historically less likely to experience the suite of components that generate strong selection pressures for the evolution of migratory behaviour. PMID:26865303

Quest for Performance: the Evolution of Modern Aircraft

NASA Technical Reports Server (NTRS)

Loftin, Lawrence K., Jr.

1985-01-01

The technical evolution of the subsonic airplane is traced from a curiosity at the beginning of World War I to the highly useful machine of today. Included are descriptions of significant aircraft which incorporated important technical innovations and served to shape the future course of aeronautical development, as well as aircraft which represented the state-of-art in a particular time frame or were much used or liked. The discussion is related primarily to aircraft configuration evolution and associated aerodynamic characteristics and, to a lesser extent, to developments in aircraft construction and propulsion. The material is presented in a manner designed to appeal to the nontechnical reader who is interested in the evolution of the airplane, as well as to students of aeronautical engineering and others with an aeronautical background.

Possible impact of global warming on the evolution of hemagglutinins from influenza a viruses.

PubMed

Yan, Shaomin; Wu, Guang

2011-02-01

To determine if global warming has an impact on the evolution of hemagglutinins from influenza A viruses, because both global warming and influenza pandemics/epidemics threaten the world. 4 706 hemagglutinins from influenza A viruses sampled from 1956 to 2009 were converted to a time-series to show their evolutionary process and compared with the global, northern hemisphere and southern hemisphere temperatures, to determine if their trends run in similar or opposite directions. Point-to-point comparisons between temperature and quantified hemagglutinins were performed for all species and for the major prevailing species. The comparisons show that the trends for both hemagglutinin evolution and temperature change run in a similar direction. Global warming has a consistent and progressive impact on the hemagglutinin evolution of influenza A viruses.

HPI Soup.

ERIC Educational Resources Information Center

Sanders, Ethan S.; Ruggles, Julie L.

2000-01-01

Discusses the evolution of human performance improvement, an outgrowth of instructional systems design and programmed instruction that emerged after World War II. Discusses the contributing disciplines (behaviorism, analytical systems, organizational learning, organizational development, systems theory, management development) and the major…

Considering body mass differences, who are the world's strongest women?

PubMed

Vanderburgh, P M; Dooman, C

2000-01-01

Allometric modeling (AM) has been used to determine the world's strongest body mass-adjusted man. Recently, however, AM was shown to demonstrate body mass bias in elite Olympic weightlifting performance. A second order polynomial (2OP) provided a better fit than AM with no body mass bias for men and women. The purpose of this study was to apply both AM and 2OP models to women's world powerlifting records (more a function of pure strength and less power than Olympic lifts) to determine the optimal model approach as well as the strongest body mass-adjusted woman in each event. Subjects were the 36 (9 per event) current women world record holders (as of Nov., 1997) for bench press (BP), deadlift (DL), squat (SQ), and total (TOT) lift (BP + DL + SQ) according to the International Powerlifting Federation (IPF). The 2OP model demonstrated the superior fit and no body mass bias as indicated by the coefficient of variation and residuals scatterplot inspection, respectively, for DL, SQ, and TOT. The AM for these three lifts, however, showed favorable bias toward the middle weight classes. The 2OP and AM yielded an essentially identical fit for BP. Although body mass-adjusted world records were dependent on the model used, Carrie Boudreau (U.S., 56-kg weight class), who received top scores in TOT and DL with both models, is arguably the world's strongest woman overall. Furthermore, although the 2OP model provides a better fit than AM for this elite population, a case can still be made for AM use, particularly in light of theoretical superiority.

Collection Evaluation and Evolution

NASA Technical Reports Server (NTRS)

Habermann, Ted; Kozimor, John

2017-01-01

We will review metadata evaluation tools and share results from our most recent CMR analysis. We will demonstrate results using Google spreadsheets and present new results in terms of number of records that include specific content. We will show evolution of UMM-compliance over time and also show results of comparing various CMR collections (NASA, non-NASA, and SciOps).

Evolution of Policy Leading to the 2006 General Dental Service Contract and Some Possible Outcomes

ERIC Educational Resources Information Center

Downer, Martin C.; Drugan, Caroline S.

2007-01-01

Background and objective: This paper was designed to rehearse the evolution of policy for the UK NHS General Dental Service (and related services) since its inception in 1948, culminating in the establishment of a new contract for general dental practitioners in 2006. Methods: Information was abstracted from the literature, historical records,…

Variety and evolution of American endoscopic image management and recording systems.

PubMed

Korman, L Y

1996-03-01

The rapid evolution of computing technology has and will continue to alter the practice of gastroenterology and gastrointestinal endoscopy. Development of communication standards for text, images, and security systems will be necessary for medicine to take advantage of high-speed computing and communications. Professional societies can have an important role in guiding the development process.

Evidence for Evolution from the Vertebrate Fossil Record.

ERIC Educational Resources Information Center

Gingerich, Philip D.

1983-01-01

Discusses three examples of evolutionary transition in the vertebrate fossil record, considering evolutionary transitions at the species level. Uses archaic squirrel-like Paleocine primates, the earliest primates of modern aspect, as examples. Also reviews new evidence on the origin of whales and their transition from land to sea. (JN)

Do We Really Understand What a Meter of Sea-level Rise by 2100 Means for the Coast?

NASA Astrophysics Data System (ADS)

Thieler, E. R.; Plant, N. G.; Gutierrez, B.

2014-12-01

Many projections of sea-level rise (SLR) by 2100 require rise rates of >7 mm/yr after about 2050. Thus, in the latter half of this century, the global average SLR rate may be higher than it has been since about 7000 years ago. That includes a prolonged period of relatively slow sea-level rise over the past 2000-4000 years, during which many coastal landforms and their associated ecosystems (e.g., barrier islands, estuaries, wetlands) matured and extended across the landscape, building rich sedimentary archives. The understanding of coastal evolution in these settings is typically based on both recent geologic history and modern process observations. The recent geologic history can be sampled from relatively accessible sedimentary records, as opposed to earlier records deposited more than ~5000 years ago, which are scarce on the transgressed continental margin. In addition, few to no modern analogs exist for many coastal settings that will experience high SLR rates and where there is significant human infrastructure and development. These settings provide valuable resources and ecosystem services on which society depends (e.g., sandy recreational beaches and fisheries), where useful projections are most needed. Thus, traditional sources of insight - the stratigraphic record and modern analogs - are lacking and limit our ability, and confidence, to predict the form, magnitude, and spatial extent of future changes to the coastal landscape. If sea-level is indeed heading towards ~1 m SLR by 2100, we have a limited timeframe to understand coastal change at higher SLR rates, communicate information to decision makers, and allow sufficient time for action. This is a moderate probability, but extraordinarily high risk, high impact scenario. It is a region of the coastal evolution parameter space that warrants focused exploration to identify critical knowledge gaps, conduct research to fill these gaps, and build our understanding. We also need to apply current knowledge to this problem; we know how to make skillful, yet imperfect models. Are we ready to set them against reality and evaluate their utility for a rapidly-changing world? We present some examples of current landscape-change predictive capability and discuss their application with and without updated understanding of higher-end SLR scenarios.

The role of biology in planetary evolution: cyanobacterial primary production in low-oxygen Proterozoic oceans.

PubMed

Hamilton, Trinity L; Bryant, Donald A; Macalady, Jennifer L

2016-02-01

Understanding the role of biology in planetary evolution remains an outstanding challenge to geobiologists. Progress towards unravelling this puzzle for Earth is hindered by the scarcity of well-preserved rocks from the Archean (4.0 to 2.5 Gyr ago) and Proterozoic (2.5 to 0.5 Gyr ago) Eons. In addition, the microscopic life that dominated Earth's biota for most of its history left a poor fossil record, consisting primarily of lithified microbial mats, rare microbial body fossils and membrane-derived hydrocarbon molecules that are still challenging to interpret. However, it is clear from the sulfur isotope record and other geochemical proxies that the production of oxygen or oxidizing power radically changed Earth's surface and atmosphere during the Proterozoic Eon, pushing it away from the more reducing conditions prevalent during the Archean. In addition to ancient rocks, our reconstruction of Earth's redox evolution is informed by our knowledge of biogeochemical cycles catalysed by extant biota. The emergence of oxygenic photosynthesis in ancient cyanobacteria represents one of the most impressive microbial innovations in Earth's history, and oxygenic photosynthesis is the largest source of O2 in the atmosphere today. Thus the study of microbial metabolisms and evolution provides an important link between extant biota and the clues from the geologic record. Here, we consider the physiology of cyanobacteria (the only microorganisms capable of oxygenic photosynthesis), their co-occurrence with anoxygenic phototrophs in a variety of environments and their persistence in low-oxygen environments, including in water columns as well as mats, throughout much of Earth's history. We examine insights gained from both the rock record and cyanobacteria presently living in early Earth analogue ecosystems and synthesize current knowledge of these ancient microbial mediators in planetary redox evolution. Our analysis supports the hypothesis that anoxygenic photosynthesis, including the activity of metabolically versatile cyanobacteria, played an important role in delaying the oxygenation of Earth's surface ocean during the Proterozoic Eon. © 2015 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.

The RNA world hypothesis: the worst theory of the early evolution of life (except for all the others)a

PubMed Central

2012-01-01

The problems associated with the RNA world hypothesis are well known. In the following I discuss some of these difficulties, some of the alternative hypotheses that have been proposed, and some of the problems with these alternative models. From a biosynthetic – as well as, arguably, evolutionary – perspective, DNA is a modified RNA, and so the chicken-and-egg dilemma of “which came first?” boils down to a choice between RNA and protein. This is not just a question of cause and effect, but also one of statistical likelihood, as the chance of two such different types of macromolecule arising simultaneously would appear unlikely. The RNA world hypothesis is an example of a ‘top down’ (or should it be ‘present back’?) approach to early evolution: how can we simplify modern biological systems to give a plausible evolutionary pathway that preserves continuity of function? The discovery that RNA possesses catalytic ability provides a potential solution: a single macromolecule could have originally carried out both replication and catalysis. RNA – which constitutes the genome of RNA viruses, and catalyzes peptide synthesis on the ribosome – could have been both the chicken and the egg! However, the following objections have been raised to the RNA world hypothesis: (i) RNA is too complex a molecule to have arisen prebiotically; (ii) RNA is inherently unstable; (iii) catalysis is a relatively rare property of long RNA sequences only; and (iv) the catalytic repertoire of RNA is too limited. I will offer some possible responses to these objections in the light of work by our and other labs. Finally, I will critically discuss an alternative theory to the RNA world hypothesis known as ‘proteins first’, which holds that proteins either preceded RNA in evolution, or – at the very least – that proteins and RNA coevolved. I will argue that, while theoretically possible, such a hypothesis is probably unprovable, and that the RNA world hypothesis, although far from perfect or complete, is the best we currently have to help understand the backstory to contemporary biology. Reviewers This article was reviewed by Eugene Koonin, Anthony Poole and Michael Yarus (nominated by Laura Landweber). PMID:22793875

Chronology of Miocene-Pliocene deposits at Split Mountain Gorge, Southern California: A record of regional tectonics and Colorado River evolution

USGS Publications Warehouse

Dorsey, R.J.; Fluette, A.; McDougall, K.; Housen, B.A.; Janecke, S.U.; Axen, G.J.; Shirvell, C.R.

2007-01-01

Late Miocene to early Pliocene deposit at Split Mountain Gorge, California, preserve a record of basinal response to changes in regional tectonics, paleogeography, and evolution of the Colorado River. The base of the Elephant Trees Formation, magnetostratigraphically dated as 8.1 ?? 0.4 Ma, provides the earliest well-dated record of extension in the southwestern Salton Trough. The oldest marine sediments are ca. 6.3 Ma. The nearly synchronous timing of marine incursion in the Salton Trough and northern Gulf of California region supports a model for localization of Pacific-North America plate motion in the Gulf ca. 6 Ma. The first appearance of Colorado River sand at the Miocene-Pliocene boundary (5.33 Ma) suggests rapid propagation of the river to the Salton Trough, and supports a lake-spillover hypothesis for initiation of the lower Colorado River. ?? 2007 Geological Society of America.

A geological history of reflecting optics.

PubMed

Parker, Andrew Richard

2005-03-22

Optical reflectors in animals are diverse and ancient. The first image-forming eye appeared around 543 million years ago. This introduced vision as a selection pressure in the evolution of animals, and consequently the evolution of adapted optical devices. The earliest known optical reflectors--diffraction gratings--are 515 Myr old. The subsequent fossil record preserves multilayer reflectors, including liquid crystals and mirrors, 'white' and 'blue' scattering structures, antireflective surfaces and the very latest addition to optical physics--photonic crystals. The aim of this article is to reveal the diversity of reflecting optics in nature, introducing the first appearance of some reflector types as they appear in the fossil record as it stands (which includes many new records) and backdating others in geological time through evolutionary analyses. This article also reveals the commercial potential for these optical devices, in terms of lessons from their nano-level designs and the possible emulation of their engineering processes--molecular self-assembly.

Detrital zircons and Earth system evolution

NASA Astrophysics Data System (ADS)

McKenzie, R.

2016-12-01

Zircon is a mineral commonly produced in silicic magmatism. Therefore, due to its resilience and exceedingly long residence times in the continental crust, detrital zircon records can be used to track processes associated with silicic magmatism throughout Earth history. In this contribution I will address the potential role of preservational biases in zircon record, and further discuss how zircon datasets can be used to help better understand the relationship between lithospheric and Earth system evolution. I will use large compilations of zircon data to trace the composition and weatherability of the continental crust, to evaluate temporal rates of crustal recycling, and finally to track spatiotemporal variation in continental arc magmatism and volcanic CO2 outgassing throughout Earth history. These records demonstrate that secular changes in plate tectonic regimes played a prominent role in modulating conditions of the ocean+atmosphere system and long-term climate state for the last 3 billion years.

Properties of four real world collaboration--competition networks

NASA Astrophysics Data System (ADS)

Fu, Chun-Hua; Xu, Xiu-Lian; He, Da-Ren

2009-03-01

Our research group has empirically investigated 9 real world collaboration networks and 25 real world cooperation-competition networks. Among the 34 real world systems, all the 9 real world collaboration networks and 6 real world cooperation-competition networks show the unimodal act-size distribution and the shifted power law distribution of degree and act-degree. We have proposed a collaboration network evolution model for an explanation of the rules [1]. The other 14 real world cooperation-competition networks show that the act-size distributions are not unimodal; instead, they take qualitatively the same shifted power law forms as the degree and act-degree distributions. The properties of four systems (the main land movie film network, Beijing restaurant network, 2004 Olympic network, and Tao-Bao notebook computer sale network) are reported in detail as examples. Via a numerical simulation, we show that the new rule can still be explained by the above-mentioned model. [1] H. Chang, B. B. Su, et al. Phsica A, 2007, 383: 687-702.

Open WorldCat and Its Impact on Academic Libraries

ERIC Educational Resources Information Center

El-Sherbini, Magda

2007-01-01

This paper analyzes librarians' reactions to the Open OCLC WorldCat. A detailed survey was sent to ARL libraries to explore what, if anything, the libraries are currently doing to prepare for these changes and how they plan to cope with the probability of having all their records open to the whole world. Survey findings indicate that most of the…

Open Access Metadata, Catalogers, and Vendors: The Future of Cataloging Records

ERIC Educational Resources Information Center

Flynn, Emily Alinder

2013-01-01

The open access (OA) movement is working to transform scholarly communication around the world, but this philosophy can also apply to metadata and cataloging records. While some notable, large academic libraries, such as Harvard University, the University of Michigan, and the University of Cambridge, released their cataloging records under OA…

The bridge of iconicity: from a world of experience to the experience of language.

PubMed

Perniss, Pamela; Vigliocco, Gabriella

2014-09-19

Iconicity, a resemblance between properties of linguistic form (both in spoken and signed languages) and meaning, has traditionally been considered to be a marginal, irrelevant phenomenon for our understanding of language processing, development and evolution. Rather, the arbitrary and symbolic nature of language has long been taken as a design feature of the human linguistic system. In this paper, we propose an alternative framework in which iconicity in face-to-face communication (spoken and signed) is a powerful vehicle for bridging between language and human sensori-motor experience, and, as such, iconicity provides a key to understanding language evolution, development and processing. In language evolution, iconicity might have played a key role in establishing displacement (the ability of language to refer beyond what is immediately present), which is core to what language does; in ontogenesis, iconicity might play a critical role in supporting referentiality (learning to map linguistic labels to objects, events, etc., in the world), which is core to vocabulary development. Finally, in language processing, iconicity could provide a mechanism to account for how language comes to be embodied (grounded in our sensory and motor systems), which is core to meaningful communication.

The bridge of iconicity: from a world of experience to the experience of language

PubMed Central

Perniss, Pamela; Vigliocco, Gabriella

2014-01-01

Iconicity, a resemblance between properties of linguistic form (both in spoken and signed languages) and meaning, has traditionally been considered to be a marginal, irrelevant phenomenon for our understanding of language processing, development and evolution. Rather, the arbitrary and symbolic nature of language has long been taken as a design feature of the human linguistic system. In this paper, we propose an alternative framework in which iconicity in face-to-face communication (spoken and signed) is a powerful vehicle for bridging between language and human sensori-motor experience, and, as such, iconicity provides a key to understanding language evolution, development and processing. In language evolution, iconicity might have played a key role in establishing displacement (the ability of language to refer beyond what is immediately present), which is core to what language does; in ontogenesis, iconicity might play a critical role in supporting referentiality (learning to map linguistic labels to objects, events, etc., in the world), which is core to vocabulary development. Finally, in language processing, iconicity could provide a mechanism to account for how language comes to be embodied (grounded in our sensory and motor systems), which is core to meaningful communication. PMID:25092668

Eco-Philosophy and Deep Ecology.

ERIC Educational Resources Information Center

Skolimowski, Henryk

1988-01-01

Criticizes the Deep Ecology Movement as a new ecological world view. Discusses the limits of this philosophy including its views of destiny, evolution and cosmology. Concludes that although its intentions are admirable, Deep Ecology leaves too much unanswered. (CW)

A new time tree reveals Earth history's imprint on the evolution of modern birds.

PubMed

Claramunt, Santiago; Cracraft, Joel

2015-12-01

Determining the timing of diversification of modern birds has been difficult. We combined DNA sequences of clock-like genes for most avian families with 130 fossil birds to generate a new time tree for Neornithes and investigated their biogeographic and diversification dynamics. We found that the most recent common ancestor of modern birds inhabited South America around 95 million years ago, but it was not until the Cretaceous-Paleogene transition (66 million years ago) that Neornithes began to diversify rapidly around the world. Birds used two main dispersion routes: reaching the Old World through North America, and reaching Australia and Zealandia through Antarctica. Net diversification rates increased during periods of global cooling, suggesting that fragmentation of tropical biomes stimulated speciation. Thus, we found pervasive evidence that avian evolution has been influenced by plate tectonics and environmental change, two basic features of Earth's dynamics.

Coral snakes predict the evolution of mimicry across New World snakes.

PubMed

Davis Rabosky, Alison R; Cox, Christian L; Rabosky, Daniel L; Title, Pascal O; Holmes, Iris A; Feldman, Anat; McGuire, Jimmy A

2016-05-05

Batesian mimicry, in which harmless species (mimics) deter predators by deceitfully imitating the warning signals of noxious species (models), generates striking cases of phenotypic convergence that are classic examples of evolution by natural selection. However, mimicry of venomous coral snakes has remained controversial because of unresolved conflict between the predictions of mimicry theory and empirical patterns in the distribution and abundance of snakes. Here we integrate distributional, phenotypic and phylogenetic data across all New World snake species to demonstrate that shifts to mimetic coloration in nonvenomous snakes are highly correlated with coral snakes in both space and time, providing overwhelming support for Batesian mimicry. We also find that bidirectional transitions between mimetic and cryptic coloration are unexpectedly frequent over both long- and short-time scales, challenging traditional views of mimicry as a stable evolutionary 'end point' and suggesting that insect and snake mimicry may have different evolutionary dynamics.

National military strategy in the post cold war era: Nuclear deterrence or an alternative. Study project

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

Pooley, G.R.

In the aftermath of the Cold War it becomes necessary to explore the validity of nuclear deterrence as the cornerstone of the United States National Military Strategy for the upcoming period of transition in international relations. Using the current world situation as a starting point, the evolving trends in international relations, arms control and nuclear proliferation, the strategic threat and the evolution of technology will be analyzed in an effort to forecast the complexion of international relations twenty years hence. Then, within this context, nuclear deterrence and a non nuclear alternative nonoffensive defense, proposed by the Danish political scientist, Bjornmore » Moller, will be examined. In the final analysis, this project will suggest an appropriate direction for the evolution of the United States' National Military Strategy which, in the opinion of the author, provides the best probability for long term world peace.« less

Coral snakes predict the evolution of mimicry across New World snakes

PubMed Central

Davis Rabosky, Alison R.; Cox, Christian L.; Rabosky, Daniel L.; Title, Pascal O.; Holmes, Iris A.; Feldman, Anat; McGuire, Jimmy A.

2016-01-01

Batesian mimicry, in which harmless species (mimics) deter predators by deceitfully imitating the warning signals of noxious species (models), generates striking cases of phenotypic convergence that are classic examples of evolution by natural selection. However, mimicry of venomous coral snakes has remained controversial because of unresolved conflict between the predictions of mimicry theory and empirical patterns in the distribution and abundance of snakes. Here we integrate distributional, phenotypic and phylogenetic data across all New World snake species to demonstrate that shifts to mimetic coloration in nonvenomous snakes are highly correlated with coral snakes in both space and time, providing overwhelming support for Batesian mimicry. We also find that bidirectional transitions between mimetic and cryptic coloration are unexpectedly frequent over both long- and short-time scales, challenging traditional views of mimicry as a stable evolutionary ‘end point' and suggesting that insect and snake mimicry may have different evolutionary dynamics. PMID:27146100

Air and Space Power Journal. Volume 22, Number 4, Winter 2008

DTIC Science & Technology

2008-01-01

otherwise be illegal. en- sign Florencio J. Yuzon, “Deliberate environmental Modi- fication through the Use of Chemical and Biological Weapons ...of war. His land- mark book Ideas and Weapons , published in 1953, analyzes the evolution of weaponry be- tween World War I and World War II, notably...it could opt to use nuclear weapons against India? How can a government prove that a foreign government (India) is the cause of internal problems

JPRS Report, Soviet Union, World Economy & International Relations, No. 3, March 1987

DTIC Science & Technology

1987-06-15

Efficiency Promotion in Industry (pp 28-40) (E. Vilkhovchenko) (not translated) •Star Wars ’ and Washington’s Allies Western Europe on SDI (pp 41-48) (G...sets of complex problems. The first is the problem S war and peace, pollution of environment and the socio-economic gap between industrially...developed capitalist countries and the developing world. The second -has taken shape as a result of the evolution of state-monopolistic capitalism and

KSC-99pp0772

NASA Image and Video Library

1999-06-27

In this fish-eye view, the Chandra X-ray Observatory rests inside the payload bay of the orbiter Columbia. Chandra is the primary payload on mission STS-93, scheduled to launch no earlier than July 20 aboard Space Shuttle Columbia. The world's most powerful X-ray telescope, Chandra will allow scientists from around the world to see previously invisible black holes and high-temperature gas clouds, giving the observatory the potential to rewrite the books on the structure and evolution of our universe

Seizing the Digital High Ground: Military Operations and Politics in the Social Media Era

DTIC Science & Technology

2015-04-13

divided on the relative threats and opportunities. Through the analysis of social media’s technological evolution, its impact on crowd behaviour , and... Through the analysis of social media’s technological evolution, its impact on crowd behaviour , and using case studies of the Arab Spring and Islamic... arguments and recommendations proposed. Web 2.0 is a term used to describe the way in which software developers and end-users utilize the World Wide Web as

Teaching evolution in the Australian classroom

NASA Astrophysics Data System (ADS)

Vozzo, Les

A summary of the key issues of controversy encountered by science teachers in Australian classrooms. Evolution, cloning and gene manipulation, fertility control, artificial intelligence, irradiation of food, the use of nuclear energy, radiation from powerlines are some of the topics discussed and debated in classrooms. What are some of the difficulties encountered by teachers when students ask questions that raise moral dilemmas and challenges entrenched beliefs and views of the world. What are some of the teaching strategies used that deal with these difficulties.

PyEvolve: a toolkit for statistical modelling of molecular evolution.

PubMed

Butterfield, Andrew; Vedagiri, Vivek; Lang, Edward; Lawrence, Cath; Wakefield, Matthew J; Isaev, Alexander; Huttley, Gavin A

2004-01-05

Examining the distribution of variation has proven an extremely profitable technique in the effort to identify sequences of biological significance. Most approaches in the field, however, evaluate only the conserved portions of sequences - ignoring the biological significance of sequence differences. A suite of sophisticated likelihood based statistical models from the field of molecular evolution provides the basis for extracting the information from the full distribution of sequence variation. The number of different problems to which phylogeny-based maximum likelihood calculations can be applied is extensive. Available software packages that can perform likelihood calculations suffer from a lack of flexibility and scalability, or employ error-prone approaches to model parameterisation. Here we describe the implementation of PyEvolve, a toolkit for the application of existing, and development of new, statistical methods for molecular evolution. We present the object architecture and design schema of PyEvolve, which includes an adaptable multi-level parallelisation schema. The approach for defining new methods is illustrated by implementing a novel dinucleotide model of substitution that includes a parameter for mutation of methylated CpG's, which required 8 lines of standard Python code to define. Benchmarking was performed using either a dinucleotide or codon substitution model applied to an alignment of BRCA1 sequences from 20 mammals, or a 10 species subset. Up to five-fold parallel performance gains over serial were recorded. Compared to leading alternative software, PyEvolve exhibited significantly better real world performance for parameter rich models with a large data set, reducing the time required for optimisation from approximately 10 days to approximately 6 hours. PyEvolve provides flexible functionality that can be used either for statistical modelling of molecular evolution, or the development of new methods in the field. The toolkit can be used interactively or by writing and executing scripts. The toolkit uses efficient processes for specifying the parameterisation of statistical models, and implements numerous optimisations that make highly parameter rich likelihood functions solvable within hours on multi-cpu hardware. PyEvolve can be readily adapted in response to changing computational demands and hardware configurations to maximise performance. PyEvolve is released under the GPL and can be downloaded from http://cbis.anu.edu.au/software.

The evolution of Yellowstone's magmatic system over the past 630 kyr: Insights from the crystal record

NASA Astrophysics Data System (ADS)

Stelten, M. E.

2017-12-01

The Yellowstone Plateau volcanic field in northwestern Wyoming is one of the world's largest, active silicic volcanic centers, and has produced three caldera-forming "super eruptions" over the past 2.1 Myr. As a result, the petrologic evolution of Yellowstone's magmatic system has been the focus of numerous studies over the past 60 years. Early studies at Yellowstone focused on characterizing whole-rock chemical and isotopic variations observed in magmas erupted over Yellowstone's lifetime. While these have provided important insights into the source of Yellowstone magmas and the processes controlling their compositional evolution though time, whole-rock studies are limited in their ability to identify the mechanisms and timescales of rhyolite generation. In contrast, much of the recent work at Yellowstone has focused on applying micro-analytical techniques to characterize the age and composition of phenocrysts hosted in Yellowstone rhyolites. These studies have greatly advanced our understanding of the magmatic system at Yellowstone and have provided crucial new insights into the mechanisms and timescales of rhyolite generation. In particular, recent work has focused on applying micro-analytical techniques to study the age and origin of the [1] three caldera-forming eruptions that produced the Huckleberry Ridge, Mesa Falls, Lava Creek tuffs and [2] post-Lava Creek tuff intracaldera rhyolites that compose the Plateau Rhyolite. As a result, a wealth of crystal-chemical data now exists for rhyolites erupted throughout Yellowstone's 2.1 Myr history. These data provide a unique opportunity to create a detailed reconstruction of Yellowstone's magmatic system through time. In this contribution, I integrate available age, chemical, and isotopic data for phenocrysts hosted in Yellowstone rhyolites to construct a model for the evolution of Yellowstone's magmatic system from the caldera-forming eruption of the Lava Creek tuff at ca. 0.63 Ma to the present day. In particular, I highlight new insights into [1] the physical nature of Yellowstone's magmatic system, [2] the ways in which the mechanisms and timescales of rhyolite generation have changed though time, and [3] implications for the current state of the Yellowstone's magmatic system.

Island life in the Cretaceous - faunal composition, biogeography, evolution, and extinction of land-living vertebrates on the Late Cretaceous European archipelago

PubMed Central

Csiki-Sava, Zoltán; Buffetaut, Eric; Ősi, Attila; Pereda-Suberbiola, Xabier; Brusatte, Stephen L.

2015-01-01

Abstract The Late Cretaceous was a time of tremendous global change, as the final stages of the Age of Dinosaurs were shaped by climate and sea level fluctuations and witness to marked paleogeographic and faunal changes, before the end-Cretaceous bolide impact. The terrestrial fossil record of Late Cretaceous Europe is becoming increasingly better understood, based largely on intensive fieldwork over the past two decades, promising new insights into latest Cretaceous faunal evolution. We review the terrestrial Late Cretaceous record from Europe and discuss its importance for understanding the paleogeography, ecology, evolution, and extinction of land-dwelling vertebrates. We review the major Late Cretaceous faunas from Austria, Hungary, France, Spain, Portugal, and Romania, as well as more fragmentary records from elsewhere in Europe. We discuss the paleogeographic background and history of assembly of these faunas, and argue that they are comprised of an endemic ‘core’ supplemented with various immigration waves. These faunas lived on an island archipelago, and we describe how this insular setting led to ecological peculiarities such as low diversity, a preponderance of primitive taxa, and marked changes in morphology (particularly body size dwarfing). We conclude by discussing the importance of the European record in understanding the end-Cretaceous extinction and show that there is no clear evidence that dinosaurs or other groups were undergoing long-term declines in Europe prior to the bolide impact. PMID:25610343

The evolution of methods for establishing evolutionary timescales

PubMed Central

2016-01-01

The fossil record is well known to be incomplete. Read literally, it provides a distorted view of the history of species divergence and extinction, because different species have different propensities to fossilize, the amount of rock fluctuates over geological timescales, as does the nature of the environments that it preserves. Even so, patterns in the fossil evidence allow us to assess the incompleteness of the fossil record. While the molecular clock can be used to extend the time estimates from fossil species to lineages not represented in the fossil record, fossils are the only source of information concerning absolute (geological) times in molecular dating analysis. We review different ways of incorporating fossil evidence in modern clock dating analyses, including node-calibrations where lineage divergence times are constrained using probability densities and tip-calibrations where fossil species at the tips of the tree are assigned dates from dated rock strata. While node-calibrations are often constructed by a crude assessment of the fossil evidence and thus involves arbitrariness, tip-calibrations may be too sensitive to the prior on divergence times or the branching process and influenced unduly affected by well-known problems of morphological character evolution, such as environmental influence on morphological phenotypes, correlation among traits, and convergent evolution in disparate species. We discuss the utility of time information from fossils in phylogeny estimation and the search for ancestors in the fossil record. This article is part of the themed issue ‘Dating species divergences using rocks and clocks’. PMID:27325838

The evolution of methods for establishing evolutionary timescales.

PubMed

Donoghue, Philip C J; Yang, Ziheng

2016-07-19

The fossil record is well known to be incomplete. Read literally, it provides a distorted view of the history of species divergence and extinction, because different species have different propensities to fossilize, the amount of rock fluctuates over geological timescales, as does the nature of the environments that it preserves. Even so, patterns in the fossil evidence allow us to assess the incompleteness of the fossil record. While the molecular clock can be used to extend the time estimates from fossil species to lineages not represented in the fossil record, fossils are the only source of information concerning absolute (geological) times in molecular dating analysis. We review different ways of incorporating fossil evidence in modern clock dating analyses, including node-calibrations where lineage divergence times are constrained using probability densities and tip-calibrations where fossil species at the tips of the tree are assigned dates from dated rock strata. While node-calibrations are often constructed by a crude assessment of the fossil evidence and thus involves arbitrariness, tip-calibrations may be too sensitive to the prior on divergence times or the branching process and influenced unduly affected by well-known problems of morphological character evolution, such as environmental influence on morphological phenotypes, correlation among traits, and convergent evolution in disparate species. We discuss the utility of time information from fossils in phylogeny estimation and the search for ancestors in the fossil record.This article is part of the themed issue 'Dating species divergences using rocks and clocks'. © 2016 The Authors.

Sky Quality Meter measurements in a colour-changing world

NASA Astrophysics Data System (ADS)

Sánchez de Miguel, A.; Aubé, M.; Zamorano, J.; Kocifaj, M.; Roby, J.; Tapia, C.

2017-05-01

The Sky Quality Meter (SQM) has become the most common device used to track the evolution of the brightness of the sky from polluted regions to first-class astronomical observatories. A vast database of SQM measurements already exists for many places in the world. Unfortunately, the SQM operates over a wide spectral band and its spectral response interacts with the sky's spectrum in a complex manner. This is why the optical signals are difficult to interpret when the data are recorded in regions with different sources of artificial light. The brightness of the night sky is linked in a complex way to ground-based light emissions, while taking into account atmospheric-induced optical distortion as well as spectral transformation from the underlying ground surfaces. While the spectral modulation of the sky's radiance has been recognized, it still remains poorly characterized and quantified. The impact of the SQM's spectral characteristics on sky-brightness measurements is analysed here for different light sources, including low- and high-pressure sodium lamps, PC-amber and white LEDs, metal halide and mercury lamps. We show that a routine conversion of radiance to magnitude is difficult, or rather impossible, because the average wavelength depends on actual atmospheric and environment conditions, the spectrum of the source and device-specific properties. We correlate SQM readings with both the Johnson astronomical photometry bands and the human system of visual perception, assuming different lighting technologies. These findings have direct implications for the processing of SQM data and for their improvement and/or remediation.

The new world of retirement income security in America.

PubMed

Quinn, Joseph F; Cahill, Kevin E

2016-01-01

We have entered a new world of retirement income security in America, with older individuals more exposed to market risk and more vulnerable to financial insecurity than prior generations. This reflects an evolution that has altered the historical vision of a financially secure retirement supported by Social Security, a defined-benefit pension plan, and individual savings. Today, 2 of these 3 retirement income sources-pensions and savings-are absent or of modest importance for many older Americans. Retirement income security now often requires earnings from continued work later in life, which exacerbates the economic vulnerability of certain segments of the population, including persons with disabilities, the oldest-old, single women, and individuals with intermittent work histories. Because of the unprecedented aging of our society, further changes to the retirement income landscape are inevitable, but policymakers do have options to help protect the financial stability of older Americans. We can begin by promoting savings at all (especially younger) ages and by removing barriers that discourage work later in life. For individuals already on the cusp of retirement, more needs to be done to educate the public about the value of delaying the receipt of Social Security benefits. Inaction now could mean a return to the days when old age and poverty were closely linked. The negative repercussions of this would extend well beyond traditional economic measures, as physical and mental health outcomes are closely tied to financial security. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Electronic medical records and the transgender patient: recommendations from the World Professional Association for Transgender Health EMR Working Group

PubMed Central

Deutsch, Madeline B; Green, Jamison; Keatley, JoAnne; Mayer, Gal; Hastings, Jennifer; Hall, Alexandra M

2013-01-01

Transgender patients have particular needs with respect to demographic information and health records; specifically, transgender patients may have a chosen name and gender identity that differs from their current legally designated name and sex. Additionally, sex-specific health information, for example, a man with a cervix or a woman with a prostate, requires special attention in electronic health record (EHR) systems. The World Professional Association for Transgender Health (WPATH) is an international multidisciplinary professional association that publishes recognized standards for the care of transgender and gender variant persons. In September 2011, the WPATH Executive Committee convened an Electronic Medical Records Working Group comprised of both expert clinicians and medical information technology specialists, to make recommendations for developers, vendors, and users of EHR systems with respect to transgender patients. These recommendations and supporting rationale are presented here. PMID:23631835

Introduction to Special Section: Paleoseismology

NASA Astrophysics Data System (ADS)

Yeats, Robert S.; Prentice, Carol S.

1996-03-01

A proverb of Confucius states "Study the past if you would divine the future." If we could learn about the past history of earthquakes on a specific fault, then we could serve society well by better forecasting the future earthquake behavior of that fault. For most of the world, the period of historical records is short: about 200 years in California and less than that in New Zealand, Oregon, and other parts of the world. And even where the historical record is thousands of years long, such as in north central China or the eastern Mediterranean region, it is commonly difficult to correlate a major historical earthquake with a specific active fault. Even if this correlation could be made without ambiguity, the recurrence intervals for many faults are longer than even a historical record of several thousand years. For these reasons, the history of large earthquakes on faults must, for the most part, be learned from the geological record.

Evidence of Archaean life - A brief appraisal

NASA Technical Reports Server (NTRS)

Schopf, J. W.

1976-01-01

Attention is called to the question of whether the meagerness of the Archaean fossil record is a function of a sparsity of preserved, cratonal, fossiliferous facies, or whether the abrupt break in the known fossil record near the Archaean-Proterozoic boundary reflects a major event in biological evolution. The paper then reviews the currently available geochemical and paleobiological data on Archaean biota. The occurrence of stromatolites in the Archaean, and the carbon isotopic composition of Archaean organic matter, both suggest strongly the existence of an Archaean biota. The presence of relatively abundant and morphologically complex microorganisms in deposits of early Proterozoic age seems to be certain evidence for a prior episode of Archaean evolution.

Changing climate in a pre-impact world: a multi-proxy paleotemperature reconstruction across the last million years of the Cretaceous

NASA Astrophysics Data System (ADS)

Woelders, L.; Vellekoop, J.; Reichart, G. J.; de Nooijer, L. J.; Sluijs, A.; Peterse, F.; Claeys, P. F.; Speijer, R. P.

2015-12-01

Climate instability during the last million years of the Cretaceous (67-66 Ma) is still poorly documented and not well understood. One of the reasons for this is that in deep time, different proxies are likely to yield different temperatures. This is because the application of calibrations based on present day temperature proxy relationships is affected by source organism evolution, differences in ocean chemistry and non-analogue processes. Only by combining temperature estimates derived from different, independent proxies, the problems with individual proxies can be cancelled out. A quantitative, multi-proxy temperature record from the latest Cretaceous therefore may provide a better insight in climate changes across this time interval. For such a multi-proxy research, sediments are required that yield both well-preserved foraminiferal calcite as well as organic biomarkers. Very few sites are known to provide such sedimentary records, but ODP Leg 174AX Site Bass River (New Jersey Shelf) has proven to be an excellent archive for paleotemperature reconstructions for the Cretaceous and Paleogene. We here present a multi-proxy, quantitative paleotemperature reconstruction of the last million years of the Cretaceous of the Bass River core. Benthic and planktic foraminiferal Mg/Ca and δ18O were determined, as well as the organic geochemical sea surface temperature proxy TEX86. This resulted in a unique coupled surface and bottom water temperature record of the latest Cretaceous. Our data suggest a ~2-6 ˚C bottom water warming and a ~4-6 ˚C surface water warming approximately 300 kyr before the Cretaceous-Paleogene boundary, followed by a cooling trend across the boundary. This warming event appears to coincide with the main phase of the Deccan Traps eruptions and therefore probably represents a global event.

Investigations of LRE-HRE-TM thin films for hybrid recording

NASA Astrophysics Data System (ADS)

Li, Zuoyi; Cheng, Xiaomin; Jin, Fang; Li, Zhen; Lin, Gengqi; Yang, Xiaofei

2005-09-01

Light rare earth-heavy rare earth-transition metal (LRE-HRE-TM) thin films are a kind of important recording media. A lot of researches have been carried out on the LRE-HRE-TM thin films to improve its properties for data storage application and fruitful results have been achieved. This report gives a glance on the evolution of the research on LRE-HRE-TM recording media. At the same time, combined with the hybrid recording technology, some experimental results obtained on LRE-HRE-TM recording media are discussed, which suggest the promising prospect of the LRE-HRE-TM media in hybrid recording application.

A high-resolution speleothem record of western equatorial Pacific rainfall: Implications for Holocene ENSO evolution

NASA Astrophysics Data System (ADS)

Chen, Sang; Hoffmann, Sharon S.; Lund, David C.; Cobb, Kim M.; Emile-Geay, Julien; Adkins, Jess F.

2016-05-01

The El Niño-Southern Oscillation (ENSO) is the primary driver of interannual climate variability in the tropics and subtropics. Despite substantial progress in understanding ocean-atmosphere feedbacks that drive ENSO today, relatively little is known about its behavior on centennial and longer timescales. Paleoclimate records from lakes, corals, molluscs and deep-sea sediments generally suggest that ENSO variability was weaker during the mid-Holocene (4-6 kyr BP) than the late Holocene (0-4 kyr BP). However, discrepancies amongst the records preclude a clear timeline of Holocene ENSO evolution and therefore the attribution of ENSO variability to specific climate forcing mechanisms. Here we present δ18 O results from a U-Th dated speleothem in Malaysian Borneo sampled at sub-annual resolution. The δ18 O of Borneo rainfall is a robust proxy of regional convective intensity and precipitation amount, both of which are directly influenced by ENSO activity. Our estimates of stalagmite δ18 O variance at ENSO periods (2-7 yr) show a significant reduction in interannual variability during the mid-Holocene (3240-3380 and 5160-5230 yr BP) relative to both the late Holocene (2390-2590 yr BP) and early Holocene (6590-6730 yr BP). The Borneo results are therefore inconsistent with lacustrine records of ENSO from the eastern equatorial Pacific that show little or no ENSO variance during the early Holocene. Instead, our results support coral, mollusc and foraminiferal records from the central and eastern equatorial Pacific that show a mid-Holocene minimum in ENSO variance. Reduced mid-Holocene interannual δ18 O variability in Borneo coincides with an overall minimum in mean δ18 O from 3.5 to 5.5 kyr BP. Persistent warm pool convection would tend to enhance the Walker circulation during the mid-Holocene, which likely contributed to reduced ENSO variance during this period. This finding implies that both convective intensity and interannual variability in Borneo are driven by coupled air-sea dynamics that are sensitive to precessional insolation forcing. Isolating the exact mechanisms that drive long-term ENSO evolution will require additional high-resolution paleoclimatic reconstructions and further investigation of Holocene tropical climate evolution using coupled climate models.

Abstracts for the International Conference on Asteroids, Comets, Meteors 1991

NASA Technical Reports Server (NTRS)

1991-01-01

Topics addressed include: chemical abundances; asteroidal belt evolution; sources of meteors and meteorites; cometary spectroscopy; gas diffusion; mathematical models; cometary nuclei; cratering records; imaging techniques; cometary composition; asteroid classification; radio telescopes and spectroscopy; magnetic fields; cosmogony; IUE observations; orbital distribution of asteroids, comets, and meteors; solar wind effects; computerized simulation; infrared remote sensing; optical properties; and orbital evolution.

Evolution of seahorses' upright posture was linked to Oligocene expansion of seagrass habitats

PubMed Central

Teske, Peter R.; Beheregaray, Luciano B.

2009-01-01

Seahorses (Syngnathidae: Hippocampus) are iconic marine teleosts that are readily identifiable by their upright posture. The fossil record is inadequate to shed light on the evolution of this trait because it lacks transitional forms. There are, however, extant syngnathid species (the pygmy pipehorses) that look like horizontally swimming seahorses and that might represent a surviving evolutionary link between the benthic seahorses and other, free-swimming members of the family Syngnathidae. Using sequence data from five nuclear loci, we confirm the sister taxon relationship between seahorses and pygmy pipehorses. Molecular dating indicates that the two taxa diverged during the Late Oligocene. During this time, tectonic events in the Indo-West Pacific resulted in the formation of vast amounts of new shallow-water areas and associated expansion of seagrass habitats that would have favoured the seahorses’ upright posture by improving their camouflage while not affecting their manoeuvrability negatively. The molecular techniques employed here provide new insights into the evolution of a taxon whose fossil record is incomplete, but whose evolutionary history is so recent that the major stages of morphological evolution are still represented in extant species. PMID:19451164

Dengue — Quo tu et quo vadis?

PubMed Central

Chen, Rubing; Vasilakis, Nikos

2011-01-01

Dengue viruses (DENV) are by far the most important arboviral pathogens in the tropics around the world, putting at risk of infection nearly a third of the global human population. DENV are members of the genus Flavivirus in the Family Flaviviridae and comprise four antigenically distinct serotypes (DENV-1-4). Although they share almost identical epidemiological features, they are genetically distinct. Phylogenetic analyses have revealed valuable insights into the origins, epidemiology and the forces that shape DENV evolution in nature. In this review, we examine the current status of DENV evolution, including but not limited to rates of evolution, selection pressures, population sizes and evolutionary constraints, and we discuss how these factors influence transmission, pathogenesis and emergence. PMID:21994796

Morphological diversity and evolution of egg and clutch structure in amphibians

USGS Publications Warehouse

Altig, Ronald; McDiarmid, Roy W.

2007-01-01

The first part of this synthesis summarizes the morphology of the jelly layers surrounding an amphibian ovum. We propose a standard terminology and discuss the evolution of jelly layers. The second part reviews the morphological diversity and arrangement of deposited eggs?the ovipositional mode; we recognize 5 morphological classes including 14 modes. We discuss some of the oviductal, ovipositional, and postovipositional events that contribute to these morphologies. We have incorporated data from taxa from throughout the world but recognize that other types will be discovered that may modify understanding of these modes. Finally, we discuss the evolutionary context of the diversity of clutch structure and present a first estimate of its evolution.

Geography and Similarity of Regional Cuisines in China

PubMed Central

Zhu, Yu-Xiao; Huang, Junming; Zhang, Zi-Ke; Zhang, Qian-Ming; Zhou, Tao; Ahn, Yong-Yeol

2013-01-01

Food occupies a central position in every culture and it is therefore of great interest to understand the evolution of food culture. The advent of the World Wide Web and online recipe repositories have begun to provide unprecedented opportunities for data-driven, quantitative study of food culture. Here we harness an online database documenting recipes from various Chinese regional cuisines and investigate the similarity of regional cuisines in terms of geography and climate. We find that geographical proximity, rather than climate proximity, is a crucial factor that determines the similarity of regional cuisines. We develop a model of regional cuisine evolution that provides helpful clues for understanding the evolution of cuisines and cultures. PMID:24260166

Geography and similarity of regional cuisines in China.

PubMed

Zhu, Yu-Xiao; Huang, Junming; Zhang, Zi-Ke; Zhang, Qian-Ming; Zhou, Tao; Ahn, Yong-Yeol

2013-01-01

Food occupies a central position in every culture and it is therefore of great interest to understand the evolution of food culture. The advent of the World Wide Web and online recipe repositories have begun to provide unprecedented opportunities for data-driven, quantitative study of food culture. Here we harness an online database documenting recipes from various Chinese regional cuisines and investigate the similarity of regional cuisines in terms of geography and climate. We find that geographical proximity, rather than climate proximity, is a crucial factor that determines the similarity of regional cuisines. We develop a model of regional cuisine evolution that provides helpful clues for understanding the evolution of cuisines and cultures.

Chaotic evolution of arms races

NASA Astrophysics Data System (ADS)

Tomochi, Masaki; Kono, Mitsuo

1998-12-01

A new set of model equations is proposed to describe the evolution of the arms race, by extending Richardson's model with special emphases that (1) power dependent defensive reaction or historical enmity could be a motive force to promote armaments, (2) a deterrent would suppress the growth of armaments, and (3) the defense reaction of one nation against the other nation depends nonlinearly on the difference in armaments between two. The set of equations is numerically solved to exhibit stationary, periodic, and chaotic behavior depending on the combinations of parameters involved. The chaotic evolution is realized when the economic situation of each country involved in the arms race is quite different, which is often observed in the real world.

Phylogenetic ecology at world scale, a new fusion between ecology and evolution.

PubMed

Westoby, Mark

2006-07-01

One fusion between ecology and evolution is well established, under the title of population biology. The years 2006-2020 will see a new fusion, likely to prove equally creative. Inputs from ecology to this second fusion will be worldwide data sets for ecological traits across many species. Inputs from evolution will be phylogenetic trees with well-resolved topology and with increasingly tight geological dates for each branch point. There will be unification of two aims: first to explain the spread of different ways of making a living, across the range of present-day species; and second, to narrate the evolutionary history that has led up to present-day ecology.

Arms races and the evolution of big fierce societies.

PubMed

Boswell, G P; Franks, N R; Britton, N F

2001-08-22

The causes of biological gigantism have received much attention, but only for individual organisms. What selection pressures might favour the evolution of gigantic societies? Here we consider the largest single-queen insect societies, those of the Old World army ant Dorylus, single colonies of which can have 20 million workers. We propose that colony gigantism in Dorylus arises as a result of an arms race and test this prediction by developing a size-structured mathematical model. We use this model for exploring and potentially explaining differences in colony size, colony aggression and colony propagation strategies in populations of New World army ants Eciton and Old World army ants Dorylus. The model shows that, by determining evolutionarily stable strategies (ESSs), differences in the trophic levels at which these army ants live feed forwards into differences in their densities and collision rates and, hence, into different strategies of growth, aggression and propagation. The model predicts large colony size and the occurrence of battles and a colony-propagation strategy involving highly asymmetrical divisions in Dorylus and that Eciton colonies should be smaller, non-combative and exhibit equitable binary fission. These ESSs are in excellent agreement with field observations and demonstrate that gargantuan societies can arise through arms races.

Virus World as an Evolutionary Network of Viruses and Capsidless Selfish Elements

PubMed Central

Dolja, Valerian V.

2014-01-01

SUMMARY Viruses were defined as one of the two principal types of organisms in the biosphere, namely, as capsid-encoding organisms in contrast to ribosome-encoding organisms, i.e., all cellular life forms. Structurally similar, apparently homologous capsids are present in a huge variety of icosahedral viruses that infect bacteria, archaea, and eukaryotes. These findings prompted the concept of the capsid as the virus “self” that defines the identity of deep, ancient viral lineages. However, several other widespread viral “hallmark genes” encode key components of the viral replication apparatus (such as polymerases and helicases) and combine with different capsid proteins, given the inherently modular character of viral evolution. Furthermore, diverse, widespread, capsidless selfish genetic elements, such as plasmids and various types of transposons, share hallmark genes with viruses. Viruses appear to have evolved from capsidless selfish elements, and vice versa, on multiple occasions during evolution. At the earliest, precellular stage of life's evolution, capsidless genetic parasites most likely emerged first and subsequently gave rise to different classes of viruses. In this review, we develop the concept of a greater virus world which forms an evolutionary network that is held together by shared conserved genes and includes both bona fide capsid-encoding viruses and different classes of capsidless replicons. Theoretical studies indicate that selfish replicons (genetic parasites) inevitably emerge in any sufficiently complex evolving ensemble of replicators. Therefore, the key signature of the greater virus world is not the presence of a capsid but rather genetic, informational parasitism itself, i.e., various degrees of reliance on the information processing systems of the host. PMID:24847023

Pushing the speed limit in enantioselective supercritical fluid chromatography.

PubMed

Regalado, Erik L; Welch, Christopher J

2015-08-01

Chromatographic enantioseparations on the order of a few seconds can be achieved by supercritical fluid chromatography using short columns packed with chiral stationary phases. The evolution of 'world record' speeds for the chromatographic separation of enantiomers has steadily dropped from an industry standard of 20-40 min just two decades ago, to a current ability to perform many enantioseparations in well under a minute. Improvements in instrument and column technologies enabled this revolution, but the ability to predict optimal separation time from an initial method development screening assay using the t(min cc) predictor greatly simplifies the development and optimization of high-speed chiral chromatographic separations. In this study, we illustrate how the use of this simple tool in combination with the workhorse technique of supercritical fluid chromatography on customized short chiral columns (1-2 cm length) allows us to achieve ultrafast enantioseparations of pharmaceutically relevant compounds on the 5-20 s scale, bringing the technique of high-throughput enantiopurity analysis out of the specialist realm and into the laboratories of most researchers. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

[Evolution of the audio-visual technologies of production and diffusion and the conditions of their application in the Third World].

PubMed

Lefebvre, M

1979-01-01

The present information production techniques are so inefficient that it is out of the question to generalize them. On the other hand audio-visual communication raises a major political problem, especially for developing countries. Audio-visual equipment has gone through adjustment phases; the example of the tape and cassette recorder is given: 2 technological improvements have completely modified its use; the transistors have allowed considerable reduction in volume and weight as well as the energy necessary; the invention of the cassette has simplified its use. Technological research is following 3 major directions: the production of equipment which consumes little energy; the improvement of electronic component production techniques (towards cheaper electronic components); finally, the designing of systems allowing to stock large quantities of information. The communication systems will probably make so much progress in the areas of technology and programming, that they will soon have very different uses than the present ones. The question is whether our civilizations will let themselves be dominated by these new systems, or whether they will succeed to turn them into progress tools.

Relative Travel Time Tomography for East Asia

NASA Astrophysics Data System (ADS)

Chang, S. J.; CHO, S.

2016-12-01

Japan island region is one of the most seismically active region in the world. As a large number of earthquakes have recently occurred along circum-Pacific belt called the ring of fire, concern over earthquakes is increasing in South Korea close to Japan. In this study, we perform seismic imaging based on relative S-wave travel-times to examine S-wave velocity upper mantle structure of East Asia. We used teleseismic events recorded at the Korea Institute of Geoscience and Mineral Resources (KIGAM) network and F-net network operated by the National Research Institute for Earth Science and Disaster Prevention (NIED). Relative travel-time residuals were obtained by a multi-channel cross-correlation method designed to automatically determine accurate relative phase arrival times. The resulting images show high-velocity anomalies along East and South side of Japan island region. These anomalies may indicate subducting Pacific and Philippine Sea plates, respectively. The velocity structure beneath southwest Japan is revealed very complex because the two slabs interact with each other there. Velocity structure of East Asia is useful to understand the tectonic evolution and the mechanism of earthquakes that occur in this region.

Cretaceous Vertebrate Tracksites - Korean Cretaceous Dinosaur Coast World Heritage Nomination Site

NASA Astrophysics Data System (ADS)

Huh, M.; Woo, K. S.; Lim, J. D.; Paik, I. S.

2009-04-01

South Korea is one of the best known regions in the world for Cretaceous fossil footprints, which are also world-renowned. Korea has produced more scientifically named bird tracks (ichnotaxa) than any other region in the world. It has also produced the world's largest pterosaur tracks. Dinosaur tracksites also have the highest frequency of vertebrate track-bearing levels currently known in any stratigraphic sequence. Among the areas that have the best track records, and the greatest scientific significance with best documentation, Korea ranks very highly. Objective analysis of important individual tracksites and tracksite regions must be based on multiple criteria including: size of site, number of tracks, trackways and track bearing levels, number of valid named ichnotaxa including types, number of scientific publications, quality of preservation. The unique and distinctive dinosaur tracksites are known as one of the world's most important dinosaur track localities. In particular, the dinosaur track sites in southern coastal area of Korea are very unique. In the sites, we have excavated over 10,000 dinosaur tracks. The Hwasun sites show diverse gaits with unusual walking patterns and postures in some tracks. The pterosaur tracks are the most immense in the world. The longest pterosaur trackway yet known from any track sites suggests that pterosaurs were competent terrestrial locomotors. This ichnofauna contains the first pterosaur tracks reported from Asia. The Haenam Uhangri pterosaur assigns to a new genus Haenamichnus which accomodates the new ichnospecies, Haenamichnus uhangriensis. At least 12 track types have been reported from the Haman and Jindong Formations (probably late Lower Cretaceous). These include the types of bird tracks assigned to Koreanornis, Jindongornipes, Ignotornis and Goseongornipes. In addition the bird tracks Hwangsanipes, Uhangrichnus, the pterosaur track Haenamichnus and the dinosaur tracks, Brontopodus, Caririchnium, Minisauripus and at least three other unnamed morphotypes are known . A total of 52 clutches containing 390 dinosaur eggs occur in several stratigraphic formations including seven dinosaur egg localities. The other fossils including turtles, crocodiles, fishes, wood fossil, plants, trace fossils and microfossils have also been discovered. The occurrences of Korean dinosaurs in diverse stratigraphic formations and sedimentological setting and in diverse sizes and morphotypes provide an opportunity to study the palaeoecologic and palaeoenvironmental conditions of the sites of the Late Cretaceous dinosaurs. Korea could serve as a global vertebrate ichnological standard for Cretaceous terrestrial sequences, and allow correlation with Japanese marine sequences to the east and classic Chinese sites to the west. The region plays a pivotal role in helping us understand vertebrate evolution and paleoecology on the margins of the Asian continent during the Cretaceous.

Time to split Salvia s.l. (Lamiaceae) - New insights from Old World Salvia phylogeny.

PubMed

Will, Maria; Claßen-Bockhoff, Regine

2017-04-01

Salvia L. is widely known as the largest genus in the mint family. A morphological modification of the androecium (lever-like stamens) was used to support this genus. However, molecular data revealed that Salvia is polyphyletic. Since phylogenetic studies largely underrepresented Old World Salvia species, we filled this gap and combined new data with existing sequences. The aim of our study was the identification of well-supported clades that provide the basis for evolutionary and taxonomic conclusions. We included ITS data (internal transcribed spacer) from 220 Salvia species, 86 of which were sequenced for the first time. Additionally, the highly variable plastid marker rpl32-trnL was sequenced, providing new data for 100 Salvia species. These sequences were combined with the accessions available from GenBank. Old World Salvia is represented herein with 57% of its species. The two datasets were analyzed separately using BI and ML approaches. Our data confirm that Salvia is polyphyletic with four distinct evolutionary lineages (Clade I-IV), including five additional genera. The clades strongly reflect the geographical distribution, i.e., Clade IV (East Asia), Clade III (Southwest Asia to Northern Africa), and Clade II (America). The origin of Salvia s.s. (Clade I) is most likely Southwest Asia. A high degree of parallel character evolution was identified in most of the Old World sections. Based on our results, we reconstructed the evolution and biogeography of Salvia s.l. and propose to split this large group into six genera, each supported by geographical distribution, morphology, and karyology. Salvia s.l. is a polyphyletic group that was originally regarded as a genus because its species share a derived stamen structure. However, phylogenetic data clearly indicate that this floral trait and other morphological characters evolved in parallel. Our study illustrates that the combination of different data sets allows a comprehensive reconstruction of taxa and characteristic evolution, both of which are a precondition for future revision. Copyright © 2017 Elsevier Inc. All rights reserved.

Natural and anthropogenic ocean noise recorded at long-term and temporary observatories

NASA Astrophysics Data System (ADS)

Grevemeyer, Ingo; Metz, Dirk; Watts, Anthony B.; Geissler, Wolfram

2017-04-01

Most people worldwide would assume that the oceans are silent. However, a number of natural phenomenon's like ocean waves, wind, lightening, ice noise, earthquakes, and submarine volcanic activity contributes to the ambient ocean noise. During their evolution, marine animals like fish and mammals have adopted in many ways to the acoustic properties of the sea. Yet in recent decades, anthropogenic and hence manmade ocean noise level has risen profoundly. Due to extreme reliance of fish and mammals on underwater sounds for basic life functions, including searching for food or mate and the absence of any mechanism to safeguard them against it, underwater noise pollution may disrupt marine life. The primary sources of low-frequency anthropogenic noise include sounds associated with shipping, military operations, oil and gas exploration and production, and even research activities. Some scientists suggest that today virtually no marine environment is without any noise pollution. Thus, all marine life forms that rely heavily on the integrity of their acoustic habitat may have to adapt to new conditions. Of greatest concern for whales are low-frequency sounds that travel long distances in the ocean. Ship propellers and motors, for instance, produce sound at low frequencies, as do natural and manmade seismic activity. These profound, loud noises reverberate in the deep ocean and can effectively mask or block vital whale communication. However, in general very little is known about the world-wide distribution of ambient ocean noise. Thus, on a global scale and considering the vast areas of the world's oceans, we know virtually nothing about noise levels in different parts of the oceans and how anthropogenic noise contributes to ambient noise. Here, we use hydrophone recordings from the UN's Comprehensive Nuclear-Test-Ban Treaty organization (CTBTO) and ocean-bottom seismometers to provide an assessment of noise in all major basins, including the Pacific, Atlantic and Indian Ocean at low frequencies of <50 Hz. Hydrophones recorded explosive volcanic eruptions, calls of Fin whales, distant seismic surveys and ship's traffic. Silent setting are characterized at 10 to 50 Hz by a noise level of 50 to 70 dB while areas affected by heavy shipping show noise levels of >100 dB. At frequencies below 1 Hz the ambient noise field is dominated by microseisms, forces by ocean gravity waves and surf.

Environmental conditions and geomorphologic changes during the Middle-Upper Paleolithic in the southern Iberian Peninsula

NASA Astrophysics Data System (ADS)

Jiménez-Espejo, Francisco J.; Rodríguez-Vidal, Joaquín; Finlayson, Clive; Martínez-Ruiz, Francisca; Carrión, José S.; García-Alix, Antonio; Paytan, Adina; Giles Pacheco, Francisco; Fa, Darren A.; Finlayson, Geraldine; Cortés-Sánchez, Miguel; Rodrigo Gámiz, Marta; González-Donoso, José M.; Linares, M. Dolores; Cáceres, Luis M.; Fernández, Santiago; Iijima, Koichi; Martínez Aguirre, Aranzazu

2013-01-01

This study utilizes geomorphology, marine sediment data, environmental reconstructions and the Gorham's Cave occupational record during the Middle to Upper Paleolithic transition to illustrate the impacts of climate changes on human population dynamics in the Western Mediterranean. Geomorphologic evolution has been dated and appears to be driven primarily by coastal dune systems, sea-level changes and seismo-tectonic evolution. Continental and marine records are well correlated and used to interpret the Gorham's Cave sequence. Specific focus is given to the three hiatus sections found in Gorham's Cave during Heinrich periods 4, 3 and 2. These time intervals are compared with a wide range of regional geomorphologic, climatic, paleoseismic, faunal and archeological records. Our data compilations indicate that climatic and local geomorphologic changes explain the Homo sapiens spp. occupational hiatuses during Heinrich periods 4 and 3. The last hiatus corresponds to the replacement of Homo neanderthalensis by H. sapiens. Records of dated cave openings, slope breccias and stalactite falls suggest that marked geomorphologic changes, seismic activity and ecological perturbations occurred during the period when Homo replacement took place.

A last updating evolution model for online social networks

NASA Astrophysics Data System (ADS)

Bu, Zhan; Xia, Zhengyou; Wang, Jiandong; Zhang, Chengcui

2013-05-01

As information technology has advanced, people are turning to electronic media more frequently for communication, and social relationships are increasingly found on online channels. However, there is very limited knowledge about the actual evolution of the online social networks. In this paper, we propose and study a novel evolution network model with the new concept of “last updating time”, which exists in many real-life online social networks. The last updating evolution network model can maintain the robustness of scale-free networks and can improve the network reliance against intentional attacks. What is more, we also found that it has the “small-world effect”, which is the inherent property of most social networks. Simulation experiment based on this model show that the results and the real-life data are consistent, which means that our model is valid.

Decadal changes in North Atlantic atmospheric circulation patterns recorded by sand spits since 1800 CE

NASA Astrophysics Data System (ADS)

Poirier, Clément; Tessier, Bernadette; Chaumillon, Éric; Bertin, Xavier; Fruergaard, Mikkel; Mouazé, Dominique; Noël, Suzanne; Weill, Pierre; Wöppelmann, Guy

2017-03-01

Present-day coastal barriers represent around 15% of the world's oceanic shorelines, and play an important role as early warning indicators of environmental change. Among them, wave-dominated barriers are dynamic landforms that tend to migrate landward in response to storms and sea-level change. High rates of sediment supply can locally offset the global retrogradation trend, providing valuable records of past environmental change occurring on transgressive coasts. However, geochronological control limits the temporal resolution of such records to millennial or centennial timescales, and the decadal or even faster response of wave-built barriers to historical climate changes is therefore poorly understood. In this study, we show that shoreline dynamics of sand spits reconstructed from old cartographic documents has been synchronous on both margins of the North Atlantic Ocean since about 1800 CE. Spit growth accelerated drastically during three periods lasting about 15 years, characterised by positive North Atlantic Oscillation (NAO) and negative East Atlantic-West Russia (EA-WR) atmospheric circulation patterns. These changes are in phase with periods of increased volcanic activity. We use a high-resolution wave hindcast (1948-2014 CE) in a reference area to confirm the association between NAO and EA-WR as a proxy for offshore and nearshore wave height and for associated longshore sediment transport (LST) involved in spit growth. A 24-month lagged correlation between sediment transport and volcanic aerosol optical thickness (concentration of ashes in the atmosphere) is observed, suggesting that spit shoreline dynamics at the decadal timescale is partially forced by external climate drivers via cascading effects on atmospheric circulation patterns and wave climate. Our results imply that NAO variability alone is not sufficient to understand the evolution of wave-built coastal environments. The associated sediment record can be used to reconstruct multi-decadal variability of other climate patterns.

Reflecting on Language. (Reflexionando Sobre el Idioma.)

ERIC Educational Resources Information Center

Mazas, Jose Garcia

1980-01-01

Covering a 500-year span, this article traces the changes in and evolution of the Spanish language from its earliest written accounts in the eleventh century to the Spanish that was brought by the Conquistadores to the New World. (DS)

The Emergence of Homo sapiens.

ERIC Educational Resources Information Center

Rensberger, Boyce

1980-01-01

Describes chronologically the evolution of the human race on earth so as to refute Darwin's theory of descent from animals. Skull fragments from sites around the world suggest at least two possible routes toward the emergence of Homo sapiens sapiens. (Author/SK)

Issues and Challenges of Teaching and Learning in 3D Virtual Worlds: Real Life Case Studies

ERIC Educational Resources Information Center

Pfeil, Ulrike; Ang, Chee Siang; Zaphiris, Panayiotis

2009-01-01

We aimed to study the characteristics and usage patterns of 3D virtual worlds in the context of teaching and learning. To achieve this, we organised a full-day workshop to explore, discuss and investigate the educational use of 3D virtual worlds. Thirty participants took part in the workshop. All conversations were recorded and transcribed for…

Real World, Pretend Universities.

ERIC Educational Resources Information Center

Ericson, Jon

1993-01-01

Corruption in college athletics requires immediate attention through monitoring and publication of student-athletes' academic records. Privacy can be protected three ways: modification of federal law concerning student records; implementing voluntary disclosure; and exposing exploitation of African-American student athletes by examining their…

From cumulative cultural transmission to evidence-based medicine: evolution of medicinal plant knowledge in Southern Italy

PubMed Central

Leonti, Marco; Staub, Peter O.; Cabras, Stefano; Castellanos, Maria Eugenia; Casu, Laura

2015-01-01

In Mediterranean cultures written records of medicinal plant use have a long tradition. This written record contributed to building a consensus about what was perceived to be an efficacious pharmacopeia. Passed down through millennia, these scripts have transmitted knowledge about plant uses, with high fidelity, to scholars and laypersons alike. Herbal medicine's importance and the long-standing written record call for a better understanding of the mechanisms influencing the transmission of contemporary medicinal plant knowledge. Here we contextualize herbal medicine within evolutionary medicine and cultural evolution. Cumulative knowledge transmission is approached by estimating the causal effect of two seminal scripts about materia medica written by Dioscorides and Galen, two classical Greco-Roman physicians, on today's medicinal plant use in the Southern Italian regions of Campania, Sardinia, and Sicily. Plant-use combinations are treated as transmissible cultural traits (or “memes”), which in analogy to the biological evolution of genetic traits, are subjected to mutation and selection. Our results suggest that until today ancient scripts have exerted a strong influence on the use of herbal medicine. We conclude that the repeated empirical testing and scientific study of health care claims is guiding and shaping the selection of efficacious treatments and evidence-based herbal medicine. PMID:26483686

From cumulative cultural transmission to evidence-based medicine: evolution of medicinal plant knowledge in Southern Italy.

PubMed

Leonti, Marco; Staub, Peter O; Cabras, Stefano; Castellanos, Maria Eugenia; Casu, Laura

2015-01-01

In Mediterranean cultures written records of medicinal plant use have a long tradition. This written record contributed to building a consensus about what was perceived to be an efficacious pharmacopeia. Passed down through millennia, these scripts have transmitted knowledge about plant uses, with high fidelity, to scholars and laypersons alike. Herbal medicine's importance and the long-standing written record call for a better understanding of the mechanisms influencing the transmission of contemporary medicinal plant knowledge. Here we contextualize herbal medicine within evolutionary medicine and cultural evolution. Cumulative knowledge transmission is approached by estimating the causal effect of two seminal scripts about materia medica written by Dioscorides and Galen, two classical Greco-Roman physicians, on today's medicinal plant use in the Southern Italian regions of Campania, Sardinia, and Sicily. Plant-use combinations are treated as transmissible cultural traits (or "memes"), which in analogy to the biological evolution of genetic traits, are subjected to mutation and selection. Our results suggest that until today ancient scripts have exerted a strong influence on the use of herbal medicine. We conclude that the repeated empirical testing and scientific study of health care claims is guiding and shaping the selection of efficacious treatments and evidence-based herbal medicine.

Small mammals taphonomy and environmental evolution during Late Pleistocene-Holocene in Monte Desert: The evidence of Gruta del Indio (central west Argentina)

NASA Astrophysics Data System (ADS)

Fernández, Fernando J.; Pardiñas, Ulyses F. J.

2018-07-01

Very few excavated sequences in southern South America provide an approximation to the environmental evolution covering the segment Late Pleistocene-Holocene. Here we present the taphonomic analysis and paleoenvironmental reconstruction based on the small mammal remains retrieved from the archaeological and paleontological site Gruta del Indio (Mendoza Province, Argentina). Radiocarbon dates situate the small mammal deposits studied within the Late Pleistocene and Holocene. Thus, these assemblages provide a record for inferring environmental evolution in the middle basin of Atuel River during the last ∼31 ky BP. Taphonomic analysis revealed that most of small mammal remains were incorporated by a little destructive nocturnal owl. Recorded species include mainly cricetid and caviomorph rodents and a single marsupial. While Pleistocene assemblages have not exclusive species, the specific richness increases towards the Holocene probably linked with the climatic variability related to ENSO. In overall, the recorded small mammals suggest environmental stability during the Late Pleistocene-Holocene, mostly associated with Monte Desert conditions. Conversely, the pollen sequence studied from Gruta del Indio was interpreted as indicator of a deep environmental change during the Pleistocene-Holocene transition, when the Patagonian steppe was replaced by Monte Desert. Potential biases linked with these kinds of proxies are discussed.

Paleo- and Neoproterozoic magmatic and tectonometamorphic evolution of the Isla Cristalina de Rivera (Nico Pérez Terrane, Uruguay)

NASA Astrophysics Data System (ADS)

Oyhantçabal, Pedro; Wagner-Eimer, Martin; Wemmer, Klaus; Schulz, Bernhard; Frei, Robert; Siegesmund, Siegfried

2012-10-01

The Isla Cristalina de Rivera crystalline complex in northeastern Uruguay underwent a multistage magmatic and metamorphic evolution. Based on SHRIMP U-Pb zircon, Th-U-Pb monazite (CHIME-EPMA method) and K-Ar age data from key units several events can be recognized: (1) multistage magmatism at 2,171-2,114 Ma, recorded on zircon of the granulitic orthogneisses and their 2,093-2,077 Ma overgrowths; (2) a distinct amphibolite facies metamorphism at ~1,980 Ma, recorded by monazite; (3) greenschist facies reworking and shearing at ca. 606 Ma (monazite and K-Ar on muscovite) along the Rivera Shear Zone, and finally (4) intrusion of the post-tectonic Sobresaliente and Las Flores granites at around 585 Ma. Lithological similarities, geographic proximity and coeval magmatic and metamorphic events indicate a similar tectonometamorphic evolution for the Isla Cristalina de Rivera, the Valentines Block in Uruguay and the Santa María Chico Granulitic Complex in southern Brazil, since at least 2.1 Ga.

Deglacial hydrography and IRD inputs: A comparison of Terminations I and II in the N.E. Atlantic

NASA Astrophysics Data System (ADS)

Hibbert, Fiona; Chapman, Mark; Austin, William; Rohling, Eelco

2015-04-01

We present a high resolution marine record (MD04-2822) from the N.E. Atlantic. This record captures the demise of the penultimate glaciation (Termination II) in high resolution. The record of co-registered proxies offers the opportunity to investigate the evolution of the last two deglacial events in the North Atlantic. The deglacial evolution of Termination II is much less well documented than the last deglaciation (Termination I). A striking feature of Termination II in the MD04-2822 record, are several large (~1 ‰) oscillations in benthic δ18O, reflecting oscillations in sea level (e.g. Grant et al., 2012, Thomas et al., 2009) and/or deep sea temperatures (cf. Skinner and Shackleton, 2006). Also notable is the markedly different pattern of surface and deep water evolution for the two deglaciations. Termination I is characterised by a short offset between benthic δ18O decrease and δ13C increase (and northwards migration of the polar front) whereas during Termination II, benthic δ13C 'improvement' (and inferred resumption in overturning) occurs only during the Marine Isotope Stage (MIS) 5e plateau, giving the marine record it's characteristic 'drawn-out' appearance. The most conspicuous feature of the penultimate deglacial in most marine cores is Heinrich event 11 (H11), an extensive episode of ice rafted debris (IRD) discharge that spread across the North Atlantic to the margin of what is now the subtropical gyre (Chapman et al., 2000). H11 generally manifests in marine records as one large and long (~ 2.5 ka) event throughout the Termination. In MD04-2822 however, there are multiple IRD events within the Termination. The continued influence of the disintegrating N. hemisphere ice sheets is also evident within the benthic δ13C and surface conditions (the polar front migrates north of the core site early within MIS 5e following a brief SST reversal).

The evolution of complex and higher organisms

NASA Technical Reports Server (NTRS)

Milne, D. (Editor); Raup, D. (Editor); Billingham, J. (Editor); Niklaus, K. (Editor); Padian, K. (Editor)

1985-01-01

The evolution of Phanerozoic life has probably been influenced by extraterrestrial events and properties of the Earth-Moon system that have not, until now, been widely recognized. Tide range, gravitational strength, the Earth's axial tilt, and other planetary properties provide background conditions whose effects on evolution may be difficult to distinguish. Solar flares, asteroid impacts, supernovae, and passage of the solar system through galactic clouds can provide catastrophic changes on the Earth with consequent characteristic extinctions. Study of the fossil record and the evolution of complex Phanerozoic life can reveal evidence of past disturbances in space near the Earth. Conversely, better understanding of environmental influences caused by extraterrestrial factors and properties of the solar system can clarify aspects of evolution, and may aid in visualizing life on other planets with different properties.

How they won Rugby World Cup through height, mass and collective experience.

PubMed

Sedeaud, Adrien; Marc, Andy; Schipman, Julien; Tafflet, Muriel; Hager, Jean-Philippe; Toussaint, Jean-François

2012-06-01

To investigate the evolution of anthropometric characteristics in World Cup rugby players and identify elements associated with performance. Age, weight and height were collected for 2692 World Cup rugby players as well as rankings in each World Cup, and collective experience of winners, finalists, semifinalists and quarter finalists in comparison to the rest of the competitors. Anthropometric parameters were compared according to age and position (back and forwards). From 1987 to 2007, forwards and backs have become heavier by 6.63 and 6.68 kg and taller by 0.61 and 1.09 cm, respectively. The collective experience of the forwards' pack is a value increasing with the final ranking attained, as well as the weight of forwards and the height of backs. For all Rugby World Cups, the highest performing teams have the tallest backs and heaviest forwards with the highest percentage of collective experience.

Small Cofactors May Assist Protein Emergence from RNA World: Clues from RNA-Protein Complexes

PubMed Central

Shen, Liang; Ji, Hong-Fang

2011-01-01

It is now widely accepted that at an early stage in the evolution of life an RNA world arose, in which RNAs both served as the genetic material and catalyzed diverse biochemical reactions. Then, proteins have gradually replaced RNAs because of their superior catalytic properties in catalysis over time. Therefore, it is important to investigate how primitive functional proteins emerged from RNA world, which can shed light on the evolutionary pathway of life from RNA world to the modern world. In this work, we proposed that the emergence of most primitive functional proteins are assisted by the early primitive nucleotide cofactors, while only a minority are induced directly by RNAs based on the analysis of RNA-protein complexes. Furthermore, the present findings have significant implication for exploring the composition of primitive RNA, i.e., adenine base as principal building blocks. PMID:21789260

Induced gravity on intersecting brane worlds. II. Cosmology

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

Corradini, Olindo; Koyama, Kazuya; Tasinato, Gianmassimo

2008-12-15

We explore cosmology of intersecting brane worlds with induced gravity on the branes. We find the cosmological equations that control the evolution of a moving codimension-one brane and a codimension-two brane that sits at the intersection. We study the Friedmann equation at the intersection, finding new contributions from the six-dimensional bulk. These higher dimensional contributions allow us to find new examples of self-accelerating configurations for the codimension-two brane at the intersection and we discuss their features.

Major Findings from The Changing Body: Health, Nutrition, and Human Development in the Western World since 1700.

PubMed

Fogel, Robert W; Grotte, Nathaniel

2011-12-01

This paper discusses findings from The Changing Body: Health, Nutrition, and Human Development in the Western World since 1700 (Cambridge University Press) The book is built on the authors' work with 300 years of height and nutrition data and discusses their findings in the context of technophysio evolution, a uniquely modern form of rapid physiological development, the result of humanity's ability to control its environment and create technological innovations to adapt to it.

sts093-s-013

NASA Image and Video Library

1999-06-27

STS093-S-013 (27 June 1999) --- In this fish-eye view, the Chandra X-ray Observatory rests inside the payload bay of the Space Shuttle Columbia at the Kennedy Space Center (KSC). Chandra is the primary payload on the STS-93 mission, scheduled to launch next month. The world's most powerful X-ray telescope, Chandra, will allow scientists from around the world to see previously invisible black holes and high-temperature gas clouds, giving the observatory the potential to rewrite the books on the structure and evolution of the universe.

KSC-99pp0771

NASA Image and Video Library

1999-06-27

In this fish-eye view, a worker oversees the movement of the Chandra X-ray Observatory into the payload bay of the orbiter Columbia. Chandra is the primary payload on mission STS-93, scheduled to launch no earlier than July 20 aboard Space Shuttle Columbia. The world's most powerful X-ray telescope, Chandra will allow scientists from around the world to see previously invisible black holes and high-temperature gas clouds, giving the observatory the potential to rewrite the books on the structure and evolution of our universe

Landsat Program

NASA Technical Reports Server (NTRS)

Markham, Brian L.; Arvidson, Terry; Barsi, Julia A.; Choate, Michael; Kaita, Edward; Levy, Raviv; Lubke, Mark; Masek, Jeffrey G.

2016-01-01

Landsat initiated the revolution in moderate resolution Earth remote sensing in the 1970s. With seven successful missions over 40+ years, Landsat has documented - and continues to document - the global Earth land surface and its evolution. The Landsat missions and sensors have evolved along with the technology from a demonstration project in the analog world of visual interpretation to an operational mission in the digital world, with incremental improvements along the way in terms of spectral, spatial, radiometric and geometric performance as well as acquisition strategy, data availability, and products.

Phylogenetics, biogeography, and staminal evolution in the tribe Mentheae (Lamiaceae).

PubMed

Drew, Bryan T; Sytsma, Kenneth J

2012-05-01

The mint family (Lamiaceae) is the sixth largest family of flowering plants, with the tribe Mentheae containing about a third of the species. We present a detailed perspective on the evolution of the tribe Mentheae based on a phylogenetic analysis of cpDNA and nrDNA that is the most comprehensive to date, a biogeographic set of analyses using a fossil-calibrated chronogram, and an examination of staminal evolution. Data from four cpDNA and two nrDNA markers representing all extant genera within the tribe Mentheae were analyzed using the programs BEAST, Lagrange, S-DIVA, and BayesTraits. BEAST was used to simultaneously estimate phylogeny and divergence times, Lagrange and S-DIVA were used for biogeographical reconstruction, and BayesTraits was used to infer staminal evolution within the tribe. Currently accepted subtribal delimitations are shown to be invalid and are updated. The Mentheae and all five of its subtribes have a Mediterranean origin and have dispersed to the New World multiple times. The vast majority of New World species of subtribe Menthinae are the product of a single dispersal event in the mid-late Miocene. At least four transitions from four stamens to two stamens have occurred within Mentheae, once in the subtribe Salviinae, once in the subtribe Lycopinae, and at least twice in the subtribe Menthinae. Worldwide cooling trends probably played a large role in the diversification and present day distribution of the tribe Mentheae. Additional work is needed to ascertain relationships within some Mentheae genera, especially in the subtribe Menthinae.

Aurora candidates from the chronicle of Qíng dynasty in several degrees of relevance

NASA Astrophysics Data System (ADS)

Kawamura, Akito D.; Hayakawa, Hisashi; Tamazawa, Harufumi; Miyahara, Hiroko; Isobe, Hiroaki

2016-10-01

We present the result of a survey of sunspots and auroras in Qíngshǐgǎo (清史稿), a draft chronicle of Qíng dynasty, for the period of 1559-1912 CE. This is a sequel to a series of works surveying historical sunspot and aurora records, and providing online data to the scientific community regarding the attained results. In total of this Qíngshǐgǎo survey, we found 111 records of night-sky luminous events with such keywords as vapor (氣, qì), cloud (雲, yún), and light (光, guāng), which may indicate auroras as well as some other phenomena. Similarly, a keyword survey for sunspots was conducted, but no sunspot record was found. In comparison with the aurora records in the western world, we found that 14 of the 111 records have a corresponding record of simultaneous observation in the western world, and hence are very likely to be aurora. In order to investigate the likeliness of the remainder of the record being aurora, we calculated the lunar age and the phase of a solar cycle for each record. After these calculations, a notable fraction of these records clustered near the full moon were to be found statistically doubtful in considerations with atmospheric optics; meanwhile, a few records of observations near the new moon could be more likely interpreted as being auroras, including three records during the Maunder minimum.

Accepting, understanding, teaching, and learning (human) evolution: Obstacles and opportunities.

PubMed

Pobiner, Briana

2016-01-01

Questions about our origin as a species are universal and compelling. Evolution-and in particular human evolution-is a subject that generates intense interest across the world, evidenced by the fact that fossil and DNA discoveries grace the covers of major science journals and magazines as well as other popular print and online media. However, virtually all national polls indicate that the majority of Americans strongly reject biological evolution as a fact-based, well-tested, and robust understanding of the history of life. In the popular mind, no topic in all of science is more contentious or polarizing than evolution and media sources often only serve to magnify this polarization by covering challenges to the teaching of evolution. In the realm of teaching, debates about evolution have shaped textbooks, curricula, standards, and policy. Challenges to accepting and understanding evolution include mistrust and denial of science, cognitive obstacles and misconceptions, language and terminology, and a religious worldview, among others. Teachers, who are on the front lines of these challenges, must be armed with the tools and techniques to teach evolution in formal education settings across grades K-16 in a straightforward, thorough, and sensitive way. Despite the potentially controversial topic of human evolution, growing research is demonstrating that a pedagogical focus on human examples is an effective and engaging way to teach core concepts of evolutionary biology. © 2016 Wiley Periodicals, Inc.

Analysis of Technique to Extract Data from the Web for Improved Performance

NASA Astrophysics Data System (ADS)

Gupta, Neena; Singh, Manish

2010-11-01

The World Wide Web rapidly guides the world into a newly amazing electronic world, where everyone can publish anything in electronic form and extract almost all the information. Extraction of information from semi structured or unstructured documents, such as web pages, is a useful yet complex task. Data extraction, which is important for many applications, extracts the records from the HTML files automatically. Ontologies can achieve a high degree of accuracy in data extraction. We analyze method for data extraction OBDE (Ontology-Based Data Extraction), which automatically extracts the query result records from the web with the help of agents. OBDE first constructs an ontology for a domain according to information matching between the query interfaces and query result pages from different web sites within the same domain. Then, the constructed domain ontology is used during data extraction to identify the query result section in a query result page and to align and label the data values in the extracted records. The ontology-assisted data extraction method is fully automatic and overcomes many of the deficiencies of current automatic data extraction methods.

The formulation of dynamical contact problems with friction in the case of systems of rigid bodies and general discrete mechanical systems—Painlevé and Kane paradoxes revisited

NASA Astrophysics Data System (ADS)

Charles, Alexandre; Ballard, Patrick

2016-08-01

The dynamics of mechanical systems with a finite number of degrees of freedom (discrete mechanical systems) is governed by the Lagrange equation which is a second-order differential equation on a Riemannian manifold (the configuration manifold). The handling of perfect (frictionless) unilateral constraints in this framework (that of Lagrange's analytical dynamics) was undertaken by Schatzman and Moreau at the beginning of the 1980s. A mathematically sound and consistent evolution problem was obtained, paving the road for many subsequent theoretical investigations. In this general evolution problem, the only reaction force which is involved is a generalized reaction force, consistently with the virtual power philosophy of Lagrange. Surprisingly, such a general formulation was never derived in the case of frictional unilateral multibody dynamics. Instead, the paradigm of the Coulomb law applying to reaction forces in the real world is generally invoked. So far, this paradigm has only enabled to obtain a consistent evolution problem in only some very few specific examples and to suggest numerical algorithms to produce computational examples (numerical modeling). In particular, it is not clear what is the evolution problem underlying the computational examples. Moreover, some of the few specific cases in which this paradigm enables to write down a precise evolution problem are known to show paradoxes: the Painlevé paradox (indeterminacy) and the Kane paradox (increase in kinetic energy due to friction). In this paper, we follow Lagrange's philosophy and formulate the frictional unilateral multibody dynamics in terms of the generalized reaction force and not in terms of the real-world reaction force. A general evolution problem that governs the dynamics is obtained for the first time. We prove that all the solutions are dissipative; that is, this new formulation is free of Kane paradox. We also prove that some indeterminacy of the Painlevé paradox is fixed in this formulation.

Reconstructing Anaximander's biological model unveils a theory of evolution akin to Darwin's, though centuries before the birth of science.

PubMed

Trevisanato, Siro Igino

2016-08-01

Anaximander's fragments on biology report a theory of evolution, which, unlike the development of other biological systems in the ancient Aegean, is naturalistic and is not based on metaphysics. According to Anaximander, evolution affected all living beings, including humans. The first biological systems formed in an aquatic environment, and were encased in a rugged and robust envelope. Evolution progressed with modifications that enabled the formation of more dynamic biological systems. For instance, after reaching land, the robust armors around aquatic beings dried up, and became brittle, This led to the loss of the armor and the development of more mobile life forms. Anaximander's theory combines observations of animals with speculations, and as such mirrors the more famous theory of evolution by Charles Darwin expressed 24 centuries later. The poor reception received by Anaximander's model in his time, illustrates a zeitgeist that would explain the contemporary lag phase in the development of biology and, as a result, medicine, in the ancient western world.

The Cosmic Century

NASA Astrophysics Data System (ADS)

Longair, Malcolm S.

2013-04-01

Part I. Stars and Stellar Evolution up to the Second World War: 1. The legacy of the nineteenth century; 2. The classification of stellar spectra; 3. Stellar structure and evolution; 4. The end points of stellar evolution; Part II. The Large-Scale Structure of the Universe, 1900-1939: 5. The Galaxy and the nature of spiral nebulae; 6. The origins of astrophysical cosmology; Part III. The Opening up of the Electromagnetic Spectrum: 7. The opening up of the electromagnetic spectrum and the new astronomies; Part IV. The Astrophysics of Stars and Galaxies since 1945: 8. Stars and stellar evolution; 9. The physics of the interstellar medium; 10. The physics of galaxies and clusters of galaxies; 11. High-energy astrophysics; Part V. Astrophysical Cosmology since 1945: 12. Astrophysical cosmology; 13. The determination of cosmological parameters; 14. The evolution of galaxies and active galaxies with cosmic epoch; 15. The origin of galaxies and the large-scale structure of the Universe; 16. The very early Universe; References; Name index; Object index; Subject index.

Darwin's goldmine is still open: variation and selection run the world

PubMed Central

Forterre, Patrick

2012-01-01

The scientific contribution of Darwin, still agonized in many religious circles, has now been recognized and celebrated by scientists from various disciplines. However, in recent years, several evolutionists have criticized Darwin as outdated, arguing that “Darwinism,” assimilated to the “tree of life,” cannot explain microbial evolution, or else was not operating in early life evolution. These critics either confuse “Darwinism” and old versions of “neo-Darwinism” or misunderstand the role of gene transfers in evolution. The core of Darwin explanation of evolution (variation/selection) remains necessary and sufficient to decipher the history of life. The enormous diversity of mechanisms underlying variations has been successfully interpreted by evolutionists in this framework and has considerably enriched the corpus of evolutionary biology without the necessity to kill the father. However, it remains for evolutionists to acknowledge interactions between cells and viruses (unknown for Darwin) as a major driving force in life evolution. PMID:22919695

Real-world perceptions of emerging event data recorder (EDR) technologies

DOT National Transportation Integrated Search

2002-01-01

This research focuses on what college-age motorists perceive to be the positive and negative aspects of implementing on-board Event Data Recorders (EDRs) in the highway mode of transport. The achievements and findings offer safety researchers insi...

Deep Time Ecosystem Engineers: The Correlation between Palaeozoic Vegetation, Evolution of Physical Riverine Habitats, and Plant and Animal Terrestrialization

NASA Astrophysics Data System (ADS)

Davies, N. S.; Gibling, M. R.

2012-04-01

Evidence from the deep time geological record attests to the fundamental importance of plant life to the construction of physical habitats within fluvial environments. Data from an extensive literature review and original fieldwork has demonstrated that many landforms and geomorphic features present in modern river systems do not appear in the deep time stratigraphic record until terrestrial vegetation had adopted certain evolutionary advances that enabled them: for example, stable point bars are associated with the development of deep rooting in the Siluro-Devonian and avulsive anabranching fluvial systems appear at the same time as extensive arborescent vegetation in the Carboniferous. In this presentation, we demonstrate a correlation between the diversification of physical fluvial sedimentary environments and the expansion of terrestrial fauna and flora throughout the Cambrian to Carboniferous, and offer an explanation for this observation that considers plants as ecosystem engineers on an evolutionary timescale. Many extrinsic factors have been considered when attempting to identify controls on the evolutionary timelines of terrestrialization for various different organisms. Factors such as O2 and CO2 levels in the atmosphere, climatic events, global tectonic organisation, sea-level changes, extinction events, weathering rates and nutrient supply are all known to have played a role. However, another factor is likely to have been a fundamental prerequisite for achieving terrestrial biodiversity: the variety of physical habitats available for newly evolved organisms. In fluvial environments, this is a function of the diversity of hydrodynamic regimes (both temporal and spatial) within the world's river systems. In a world where only sheet-like ephemeral braided rivers existed, such as appears to be the case in pre-vegetation settings, both the geographic extent of riparian margins and the diversity of hydrodynamic regimes would be minimal. However, as fluvial corridors narrowed throughout the Ordovician and Silurian, the potential importance of riparian zones as a global biome would have increased as they became more extensive in continental environments. Furthermore, the move towards climatic controls on the ephemeral or perennial nature of streams would have boosted the diversity of temporally diverse hydrodynamic regimes. As single-thread meandering channels and extensive muddy floodplains, stabilised by vegetation, became significant components of the global suite of alluvial geomorphic components throughout the Siluro-Devonian, further diversification of the extent and diversity of physical habitats within the global riparian biome occurred. Into the Carboniferous, the evolution of the anabranching habit within alluvial systems created further new physical landforms for colonization and would have promoted increasingly complex hyporheic flow regimes. Furthermore the associated advent of arborescent vegetation and, specifically, the large woody debris supplied by this, would have created a wealth of new microhabitats for continental organisms. The expanding extent and diversity of physical alluvial niches during the Palaeozoic can be argued to be an underappreciated driver of the terrestrialization of early continental life. The study of the deep time fossil and stratigraphic record also illustrates that vegetation is a fundamental prerequisite for the creation of biogeomorphic alluvial landforms and physical habitats and microhabitats.

Genetic diversity and trait genomic prediction in a pea diversity panel.

PubMed

Burstin, Judith; Salloignon, Pauline; Chabert-Martinello, Marianne; Magnin-Robert, Jean-Bernard; Siol, Mathieu; Jacquin, Françoise; Chauveau, Aurélie; Pont, Caroline; Aubert, Grégoire; Delaitre, Catherine; Truntzer, Caroline; Duc, Gérard

2015-02-21

Pea (Pisum sativum L.), a major pulse crop grown for its protein-rich seeds, is an important component of agroecological cropping systems in diverse regions of the world. New breeding challenges imposed by global climate change and new regulations urge pea breeders to undertake more efficient methods of selection and better take advantage of the large genetic diversity present in the Pisum sativum genepool. Diversity studies conducted so far in pea used Simple Sequence Repeat (SSR) and Retrotransposon Based Insertion Polymorphism (RBIP) markers. Recently, SNP marker panels have been developed that will be useful for genetic diversity assessment and marker-assisted selection. A collection of diverse pea accessions, including landraces and cultivars of garden, field or fodder peas as well as wild peas was characterised at the molecular level using newly developed SNP markers, as well as SSR markers and RBIP markers. The three types of markers were used to describe the structure of the collection and revealed different pictures of the genetic diversity among the collection. SSR showed the fastest rate of evolution and RBIP the slowest rate of evolution, pointing to their contrasted mode of evolution. SNP markers were then used to predict phenotypes -the date of flowering (BegFlo), the number of seeds per plant (Nseed) and thousand seed weight (TSW)- that were recorded for the collection. Different statistical methods were tested including the LASSO (Least Absolute Shrinkage ans Selection Operator), PLS (Partial Least Squares), SPLS (Sparse Partial Least Squares), Bayes A, Bayes B and GBLUP (Genomic Best Linear Unbiased Prediction) methods and the structure of the collection was taken into account in the prediction. Despite a limited number of 331 markers used for prediction, TSW was reliably predicted. The development of marker assisted selection has not reached its full potential in pea until now. This paper shows that the high-throughput SNP arrays that are being developed will most probably allow for a more efficient selection in this species.

A case study in evolutionary contingency.

PubMed

Blount, Zachary D

2016-08-01

Biological evolution is a fundamentally historical phenomenon in which intertwined stochastic and deterministic processes shape lineages with long, continuous histories that exist in a changing world that has a history of its own. The degree to which these characteristics render evolution historically contingent, and evolutionary outcomes thereby unpredictably sensitive to history has been the subject of considerable debate in recent decades. Microbial evolution experiments have proven among the most fruitful means of empirically investigating the issue of historical contingency in evolution. One such experiment is the Escherichia coli Long-Term Evolution Experiment (LTEE), in which twelve populations founded from the same clone of E. coli have evolved in parallel under identical conditions. Aerobic growth on citrate (Cit(+)), a novel trait for E. coli, evolved in one of these populations after more than 30,000 generations. Experimental replays of this population's evolution from various points in its history showed that the Cit(+) trait was historically contingent upon earlier mutations that potentiated the trait by rendering it mutationally accessible. Here I review this case of evolutionary contingency and discuss what it implies about the importance of historical contingency arising from the core processes of evolution. Copyright © 2015 Elsevier Ltd. All rights reserved.

Landscape evolution of Antarctica

USGS Publications Warehouse

Jamieson, S.S.R.; Sugden, D.E.

2007-01-01

shelf before retreating to its present dimensions at ~13.5 Ma. Subsequent changes in ice extent have been forced mainly by sea-level change. Weathering rates of exposed bedrock have been remarkably slow at high elevations around the margin of East Antarctica under the hyperarid polar climate of the last ~13.5 Ma, offering potential for a long quantitative record of ice-sheet evolution with techniques such as cosmogenic isotope analysis

Workshop on the Archean Mantle

NASA Technical Reports Server (NTRS)

Ashwal, L. D. (Editor)

1989-01-01

The Workshop on the Archaen mantle considers and discusses evidence for the nature of earth's Archaen mantle, including its composition, age and structure, influence on the origin and evolution of earth's crust, and relationship to mantle and crustal evolution of the other terrestrial planets. The summaries of presentations and discussions are based on recordings made during the workshop and on notes taken by those who agreed to serve as summarizers.