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1.
Heliyon ; 10(10): e31042, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38807888

RESUMEN

Purpose: This research seeks to extend previous research into student discipline and competitiveness, at the macro or national level, to the micro or individual level. The role of factors with the potential to impact individual competitiveness, namely the expectations of the mother and the father, the importance of school discipline played in primary and secondary schools, and past participation in sport and music were examined. Design/methodology/approach: Data from a sample of current university students and recent graduates representing Western (the United States) and Asian regions (South Korea and China) were analysed using multiple regressions to establish the explanatory power of independent variables in the competitiveness model, including testing for moderation effects of country of birth. Results: The study found that personal discipline is significantly associated with individual competitiveness. The importance placed on discipline in primary schools was found to predict individual competitiveness as were parents' expectations, yet with nuances in terms of maternal and paternal expectations. Surprisingly, neither participation in music nor discipline at secondary school was found to significantly associate with individual competitiveness. At the same time, the study did find moderating effects of country of birth and the number of years students played sport in predicting competitiveness. Originality/value: Guided by the Ecological Systems Theory and the notion of the Pygmalion effect, we develop a framework of factors that shape an individual's competitiveness. The results make several theoretical contributions by establishing new drivers of individual competitiveness, and as such illuminating the importance of discipline during schooling and how parental expectations drive performance. Implications for employers, educational institutions, and parents are outlined and directions for further research are offered.

2.
Philos Trans R Soc Lond B Biol Sci ; 379(1902): 20230021, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38583478

RESUMEN

Today's biodiversity crisis fundamentally threatens the habitability of the planet, thus ranking among the primary human challenges of our time. Much emphasis is currently placed on the loss of biodiversity in the Anthropocene, yet these debates often portray biodiversity as a purely natural phenomenon without much consideration of its human dimensions and frequently lack long-term vistas. This paper offers a deep-time perspective on the key role of the evolving human niche in ecosystem functioning and biodiversity dynamics. We summarize research on past hunter-gatherer ecosystem contributions and argue that human-environment feedback systems with important biodiversity consequences are probably a recurrent feature of the Late Pleistocene, perhaps with even deeper roots. We update current understandings of the human niche in this light and suggest that the formation of palaeo-synanthropic niches in other animals proffers a powerful model system to investigate recursive interactions of foragers and ecosystems. Archaeology holds important knowledge here and shows that ecosystem contributions vary greatly in relation to different human lifeways, some of which are lost today. We therefore recommend paying more attention to the intricate relationship between biodiversity and cultural diversity, contending that promotion of the former depends on fostering the latter. This article is part of the theme issue 'Ecological novelty and planetary stewardship: biodiversity dynamics in a transforming biosphere'.


Asunto(s)
Biodiversidad , Ecosistema , Animales , Humanos , Arqueología
3.
Nat Ecol Evol ; 7(8): 1302-1314, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37349568

RESUMEN

The earlier Gravettian of Southern Moravia-the Pavlovian-is notable for the many raven bones (Corvus corax) documented in its faunal assemblages. On the basis of the rich zooarchaeological and settlement data from the Pavlovian, previous work suggested that common ravens were attracted by human domestic activities and subsequently captured by Pavlovian people, presumably for feathers and perhaps food. Here, we report independent δ15N, δ13C and δ34S stable isotope data obtained from 12 adult ravens from the Pavlovian key sites of Predmostí I, Pavlov I and Dolní Vestonice I to test this idea. We show that Pavlovian ravens regularly fed on larger herbivores and especially mammoths, aligning in feeding preferences with contemporaneous Gravettian foragers. We argue that opportunistic-generalist ravens were encouraged by human settlement and carcass provisioning. Our data may thus provide surprisingly early evidence for incipient synanthropism among Palaeolithic ravens. We suggest that anthropogenic manipulation of carrion supply dynamics furnished unique contexts for the emergence of human-oriented animal behaviours, in turn promoting novel human foraging opportunities-dynamics which are therefore important for understanding early hunter-gatherer ecosystem impacts.


Asunto(s)
Cuervos , Animales , Adulto , Humanos , Ecosistema , Ecología , Dieta , Huesos
4.
Evol Med Public Health ; 11(1): 129-138, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37252429

RESUMEN

Background and objectives: Virtual teaching tools have gained increasing importance in recent years. In particular, the COVID-19 pandemic has reinforced the need for media-based and self-regulated tools. What is missing are tools that allow us to interlink highly interdisciplinary fields such as evolutionary medicine and, at the same time, allow us to adapt content to different lectures. Methodology: We designed an interactive online teaching tool, namely, the Mummy Explorer, using open-access software (Google Web Designer), and we provided a freely downloadable template. We tested the tool on students and lecturers of evolutionary medicine using questionnaires and improved the tool according to their feedback. Results: The tool has a modular design and provides an overview of a virtual mummy excavation, including the subfields of palaeopathology, paleoradiology, cultural and ethnographic context, provenance studies, paleogenetics, and physiological analyses. The template allows lecturers to generate their own versions of the tool for any topic of interest by simply changing the text and pictures. Tests undertaken with students of evolutionary medicine showed that the tool was helpful during their studies. Lecturers commented that they appreciated having a similar tool in other fields. Conclusions and implications: Mummy Explorer fills a gap in the virtual teaching landscape of highly interdisciplinary fields such as evolutionary medicine. It will be offered for free download and can be adapted to any educational topic. Translations into German and possibly other languages are in progress.

5.
Nature ; 607(7918): 313-320, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35768506

RESUMEN

The grey wolf (Canis lupus) was the first species to give rise to a domestic population, and they remained widespread throughout the last Ice Age when many other large mammal species went extinct. Little is known, however, about the history and possible extinction of past wolf populations or when and where the wolf progenitors of the present-day dog lineage (Canis familiaris) lived1-8. Here we analysed 72 ancient wolf genomes spanning the last 100,000 years from Europe, Siberia and North America. We found that wolf populations were highly connected throughout the Late Pleistocene, with levels of differentiation an order of magnitude lower than they are today. This population connectivity allowed us to detect natural selection across the time series, including rapid fixation of mutations in the gene IFT88 40,000-30,000 years ago. We show that dogs are overall more closely related to ancient wolves from eastern Eurasia than to those from western Eurasia, suggesting a domestication process in the east. However, we also found that dogs in the Near East and Africa derive up to half of their ancestry from a distinct population related to modern southwest Eurasian wolves, reflecting either an independent domestication process or admixture from local wolves. None of the analysed ancient wolf genomes is a direct match for either of these dog ancestries, meaning that the exact progenitor populations remain to be located.


Asunto(s)
Perros , Genoma , Genómica , Filogenia , Lobos , África , Animales , ADN Antiguo/análisis , Perros/genética , Domesticación , Europa (Continente) , Genoma/genética , Historia Antigua , Medio Oriente , Mutación , América del Norte , Selección Genética , Siberia , Proteínas Supresoras de Tumor/genética , Lobos/clasificación , Lobos/genética
6.
Sci Rep ; 11(1): 5137, 2021 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-33664287

RESUMEN

Dogs are known to be the oldest animals domesticated by humans. Although many studies have examined wolf domestication, the geographic and temporal origin of this process is still being debated. To address this issue, our study sheds new light on the early stages of wolf domestication during the Magdalenian period (16-14 ka cal BP) in the Hegau Jura region (Southwestern Germany and Switzerland). By combining morphology, genetics, and isotopes, our multidisciplinary approach helps to evaluate alternate processes driving the early phases of domestication. The isotope analysis uncovered a restricted, low δ15N protein diet for all analyzed Gnirshöhle specimens, while morphological examinations and phylogenetic relationships did not unequivocally assign them to one or the other canid lineage. Intriguingly, the newly generated mitochondrial canid genomes span the entire genetic diversity of modern dogs and wolves. Such high mitochondrial diversity could imply that Magdalenian people tamed and reared animals originating from different wolf lineages. We discuss our results in light of three ecological hypotheses and conclude that both domestication and the existence of a specialized wolf ecomorph are highly probable. However, due to their proximity to humans and a restricted diet, we propose domestication as the most likely scenario explaining the patterns observed herein.


Asunto(s)
Canidae/genética , ADN Mitocondrial/genética , Filogenia , Lobos/genética , Animales , Cuevas , Perros , Domesticación , Fósiles , Suiza
7.
PLoS One ; 15(7): e0235692, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32697783

RESUMEN

Nowadays, opportunistic small predators, such as foxes (Vulpes vulpes and Vulpes lagopus), are well known to be very adaptable to human modified ecosystems. However, the timing of the start of this phenomenon in terms of human impact on ecosystems and of the implications for foxes has hardly been studied. We hypothesize that foxes can be used as an indicator of past human impact on ecosystems, as a reflection of population densities and consequently to track back the influence of humans on the Pleistocene environment. To test this hypothesis, we used stable isotope analysis (δ13C, δ15N) of bone collagen extracted from faunal remains from several archaeological sites located in the Swabian Jura (southwest Germany) and covering a time range over three important cultural periods, namely the Middle Palaeolithic (older than 42,000 years ago) attributed to Neanderthals, and the early Upper Palaeolithic periods Aurignacian and Gravettian (42,000 to 30,000 years ago) attributed to modern humans. We then ran Bayesian statistic systems (SIBER, mixSIAR) to reconstruct the trophic niches and diets of Pleistocene foxes. We observed that during the Middle Palaeolithic period, when Neanderthals sparsely populated the Swabian Jura, the niches occupied by foxes suggest a natural trophic behavior. In contrast, during the early Upper Palaeolithic periods, a new trophic fox niche appeared, characterized by a restricted diet on reindeer. This trophic niche could be due to the consumption of human subsidies related to a higher human population density and the resulting higher impact on the Pleistocene environment by modern humans compared to Neanderthals. Furthermore, our study suggests that, a synanthropic commensal behavior of foxes started already in the Aurignacian, around 42,000 years ago.


Asunto(s)
Dieta/veterinaria , Ecosistema , Zorros/fisiología , Animales , Arqueología , Teorema de Bayes , Huesos/metabolismo , Isótopos de Carbono/análisis , Colágeno/química , Colágeno/metabolismo , Fósiles/historia , Historia Antigua , Humanos , Hombre de Neandertal , Isótopos de Nitrógeno/análisis
8.
Proc Natl Acad Sci U S A ; 117(30): 17710-17719, 2020 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-32661161

RESUMEN

Cat remains from Poland dated to 4,200 to 2,300 y BCE are currently the earliest evidence for the migration of the Near Eastern cat (NE cat), the ancestor of domestic cats, into Central Europe. This early immigration preceded the known establishment of housecat populations in the region by around 3,000 y. One hypothesis assumed that NE cats followed the migration of early farmers as synanthropes. In this study, we analyze the stable isotopes in six samples of Late Neolithic NE cat bones and further 34 of the associated fauna, including the European wildcat. We approximate the diet and trophic ecology of Late Neolithic felids in a broad context of contemporary wild and domestic animals and humans. In addition, we compared the ecology of Late Neolithic NE cats with the earliest domestic cats known from the territory of Poland, dating to the Roman Period. Our results reveal that human agricultural activity during the Late Neolithic had already impacted the isotopic signature of rodents in the ecosystem. These synanthropic pests constituted a significant proportion of the NE cat's diet. Our interpretation is that Late Neolithic NE cats were opportunistic synanthropes, most probably free-living individuals (i.e., not directly relying on a human food supply). We explore niche partitioning between studied NE cats and the contemporary native European wildcats. We find only minor differences between the isotopic ecology of both these taxa. We conclude that, after the appearance of the NE cat, both felid taxa shared the ecological niches.


Asunto(s)
Animales Domésticos , Arqueología , Dieta , Fósiles , Animales , Gatos , Colágeno , Ecosistema , Europa (Continente) , Geografía , Humanos , Marcaje Isotópico
9.
Sci Rep ; 9(1): 4433, 2019 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-30872714

RESUMEN

Correlating cultural, technological and ecological aspects of both Upper Pleistocene modern humans (UPMHs) and Neandertals provides a useful approach for achieving robust predictions about what makes us human. Here we present ecological information for a period of special relevance in human evolution, the time of replacement of Neandertals by modern humans during the Late Pleistocene in Europe. Using the stable isotopic approach, we shed light on aspects of diet and mobility of the late Neandertals and UPMHs from the cave sites of the Troisième caverne of Goyet and Spy in Belgium. We demonstrate that their diet was essentially similar, relying on the same terrestrial herbivores, whereas mobility strategies indicate considerable differences between Neandertal groups, as well as in comparison to UPMHs. Our results indicate that UPMHs exploited their environment to a greater extent than Neandertals and support the hypothesis that UPMHs had a substantial impact not only on the population dynamics of large mammals but also on the whole structure of the ecosystem since their initial arrival in Europe.


Asunto(s)
Evolución Biológica , Radioisótopos de Carbono/análisis , Dieta/tendencias , Ecosistema , Emigración e Inmigración/estadística & datos numéricos , Radioisótopos de Nitrógeno/análisis , Radioisótopos de Azufre/análisis , Animales , Antropología Física , Dieta/estadística & datos numéricos , Proteínas en la Dieta/análisis , Fósiles , Hominidae , Humanos , Hombre de Neandertal
10.
J Med Chem ; 50(12): 2807-17, 2007 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-17500511

RESUMEN

High-throughput screening of a subset of the J&J compound library containing the carboxylic acid functional group uncovered a bromophenyl derivative as a moderate potent GPR40 agonist. Chemical elaboration of this bromophenyl led to the discovery of a novel series of GPR40 agonists with submicromolar potency. Among them, 22 and 24 behaved as full agonists when compared to the endogenous GPR40 ligand linolenic acid in a functional Ca+2 flux assay in HEK cells expressing GPR40 receptor. Several GPR40 agonists have also demonstrated the ability to induce glucose-mediated insulin secretion in the mouse MIN6 pancreatic beta-cell line. Our data supports the hypothesis that GPR40 may play an important role in fatty acid-mediated glucose-dependent insulin secretion. Compound 22 exhibited good pharmacokinetic profile in rat and may serve as a good candidate for in vivo study and may help to determine if GPR40 agonists would be beneficial in the treatment of type II diabetes.


Asunto(s)
Fenilpropionatos/síntesis química , Propionatos/síntesis química , Receptores Acoplados a Proteínas G/agonistas , Animales , Disponibilidad Biológica , Calcio/metabolismo , Línea Celular , Humanos , Hipoglucemiantes/síntesis química , Hipoglucemiantes/farmacocinética , Hipoglucemiantes/farmacología , Insulina/metabolismo , Secreción de Insulina , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Ratones , Fenilpropionatos/farmacocinética , Fenilpropionatos/farmacología , Propionatos/farmacocinética , Propionatos/farmacología , Ratas , Estereoisomerismo , Relación Estructura-Actividad
11.
J Am Soc Echocardiogr ; 16(12): 1244-51, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14652603

RESUMEN

Automated border-detection techniques such as acoustic quantification have proven accurate and useful for quantifying left ventricular (LV) function. We acquired LV acoustic quantification waveforms from the parasternal short-axis window in 140 healthy patients in the age range of 16 to 78 years. Signal-averaged waveforms were analyzed for parameters of systolic and diastolic performance. The average fractional area change was 54 +/- 12%, and there were no significant changes in LV systolic function in the age range studied. There were significant changes in diastolic parameters with aging. The percentage of contribution to total LV filling occurring during atrial filling nearly tripled during the 6 decades studied, from 13% in the youngest cohort to 36% in the eighth decade of life. This study provides normal reference values for systolic and diastolic parameters of LV function determined from signal-averaged acoustic quantification waveforms acquired from the parasternal short-axis view in adult and adolescent patients over a wide age range.


Asunto(s)
Diástole/fisiología , Sístole/fisiología , Función Ventricular Izquierda , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Volumen Sistólico
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