123,162 research outputs found

    Molar macrowear reveals Neanderthal eco-geographic dietary variation

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    Neanderthal diets are reported to be based mainly on the consumption of large and medium sized herbivores, while the exploitation of other food types including plants has also been demonstrated. Though some studies conclude that early Homo sapiens were active hunters, the analyses of faunal assemblages, stone tool technologies and stable isotopic studies indicate that they exploited broader dietary resources than Neanderthals. Whereas previous studies assume taxon-specific dietary specializations, we suggest here that the diet of both Neanderthals and early Homo sapiens is determined by ecological conditions. We analyzed molar wear patterns using occlusal fingerprint analysis derived from optical 3D topometry. Molar macrowear accumulates during the lifespan of an individual and thus reflects diet over long periods. Neanderthal and early Homo sapiens maxillary molar macrowear indicates strong eco-geographic dietary variation independent of taxonomic affinities. Based on comparisons with modern hunter-gatherer populations with known diets, Neanderthals as well as early Homo sapiens show high dietary variability in Mediterranean evergreen habitats but a more restricted diet in upper latitude steppe/coniferous forest environments, suggesting a significant consumption of high protein meat resources

    The rise of the technobionts: toward a new ontology to understand current planetary crisis

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    Inhere we expand the concept of Holobiont to incorporate niche construction theory in order to increase our understanding of the current planetary crisis. By this, we propose a new ontology, the Ecobiont, as the basic evolutionary unit of analysis. We make the case of Homo Sapiens organized around modern cities (technobionts) as a different Ecobiont from classical Homo Sapiens (i.e. Hunter- gatherers Homo Sapiens). We consider that Ecobiont ontology helps to make visible the coupling of Homo Sapiens with other biological entities under processes of natural and cultural evolution. Not to see this coupling hidden systemic risks and enhance the probability of catastrophic events. So Ecobiont ontology is necessary to understand and respond to the current planetary crisis

    Rare dental trait provides morphological evidence of archaic introgression in Asian fossil record

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    The recently described Denisovan hemimandible from Xiahe, China [F. Chen et al., (2019) Nature 569, 409–412], possesses an unusual dental feature: a 3-rooted lower second molar. A survey of the clinical and bioarchaeological literature demonstrates that the 3-rooted lower molar is rare (less than 3.5% occurrence) in non-Asian Homo sapiens. In contrast, its presence in Asian-derived populations can exceed 40% in China and the New World. It has long been thought that the prevalence of 3-rooted lower molars in Asia is a relatively late acquisition occurring well after the origin and dispersal of H. sapiens. However, the presence of a 3-rooted lower second molar in this 160,000-y-old fossil hominin suggests greater antiquity for the trait. Importantly, it also provides morphological evidence of a strong link between archaic and recent Asian H. sapiens populations. This link provides compelling evidence that modern Asian lineages acquired the 3-rooted lower molar via introgression from Denisovans

    (WP 2018-02) Extending Behavioral Economics’ Methodological Critique of Rational Choice Theory to Include Counterfactual Reasoning

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    This paper extends behavioral economics’ realist methodological critique of rational choice theory to include the type of logical reasoning underlying its axiomatic foundations. A purely realist critique ignores Kahneman’s emphasis on how the theory’s axiomatic foundations make it normative. I extend his critique to the theory’s reliance on classical logic, which excludes the concept of possibility employed in counterfactual reasoning. Nudge theory reflects this in employing counterfactual conditionals. This answers the complaint that the Homo sapiens agent conception ultimately reduces to a Homo economicus conception, and also provides grounds for treating Homo sapiens as an adaptive, non-optimizing, reflexive agent

    Homo heidelbergensis: The Tool to Our Success

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    Homo heidelbergensis, a physiological variant of the species Homo sapien, is an extinct species that existed in both Europe and parts of Asia from 700,000 years ago to roughly 300,000 years ago (carbon dating). This “subspecies” of Homo sapiens, as it is formally classified, is a direct ancestor of anatomically modern humans, and is understood to have many of the same physiological characteristics as those of anatomically modern humans while still expressing many of the same physiological attributes of Homo erectus, an earlier human ancestor. Since Homo heidelbergensis represents attributes of both species, it has therefore earned the classification as a subspecies of Homo sapiens and Homo erectus. Homo heidelbergensis, like anatomically modern humans, is the byproduct of millions of years of natural selection and genetic variation. It is understood through current scientific theory that roughly 200,000 years ago (carbon dating), archaic Homo sapiens and Homo erectus left Africa in pursuit of the small and large animal game that were migrating north into Europe and Asia. As they migrated north with their food source, the climates that these individuals faced were completely opposite to the environment that they were subjected to in Africa

    Core promoter short tandem repeats as evolutionary switch codes for primate speciation

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    Alteration in gene expression levels underlies many of the phenotypic differences across species. Because of their highly mutable nature, proximity to the +1 transcription start site (TSS), and the emerging evidence of functional impact on gene expression, core promoter short tandem repeats (STRs) may be considered an ideal source of variation across species. In a genome-scale analysis of the entire Homo sapiens protein-coding genes, we have previously identified core promoters with at least one STR of ≥6-repeats, with possible selective advantage in this species. In the current study, we performed reverse analysis of the entire Homo sapiens orthologous genes in mouse in the Ensembl database, in order to identify conserved STRs that have shrunk as an evolutionary advantage to humans. Two protocols were used to minimize ascertainment bias. Firstly, two species sharing a more recent ancestor with Homo sapiens (i.e. Pan troglodytes and Gorilla gorilla gorilla) were also included in the study. Secondly, four non-primate species encompassing the major orders across Mammals, including Scandentia, Laurasiatheria, Afrotheria, and Xenarthra were analyzed as out-groups. We introduce STR evolutionary events specifically identical in primates (i.e. Homo sapiens, Pan troglodytes, and Gorilla gorilla gorilla) vs. non-primate out-groups. The average frequency of the identically shared STR motifs across those primates ranged between 0.00005 and 0.06. The identified genes are involved in important evolutionary and developmental processes, such as normal craniofacial development (TFAP2B), regulation of cell shape (PALMD), learning and long-term memory (RGS14), nervous system development (GFRA2), embryonic limb morphogenesis (PBX2), and forebrain development (APAF1). We provide evidence of core promoter STRs as evolutionary switch codes for primate speciation, and the first instance of identity-by-descent for those motifs at the interspecies level. © 2014 Wiley Periodicals, Inc

    Could There Have Been Human Families Where Parents Came from Different Populations: Denisovans, Neanderthals or Sapiens?

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    No later than ~500kya the population of Homo sapiens split into three lin-eages of independently evolving human populations: Sapiens, Neanderthals and Den-isovans. After several hundred thousands years, they met several times and interbred with low frequency. Evidence of coupling between them is found in fossil records of Neanderthal – Sapiens offspring (Oase 1) and Neanderthal – Denisovans (Denisova 11)offspring. Moreover, the analysis of ancient and present-day population DNA shows that there were several significant gene flows between populations. Many introgressed sequences from Denisovans and Neanderthals were identified in genomes of currently living populations. All these data, according to biological species definition, may in-dicate that populations of H. sapiens sapiens and two extinct populations H. sapiens neanderthalensis and H. sapiens denisovensis are one species. Ontological transitions from pre-human beings to humans might have happened before the initial splitting of the Homo sapiens population or after the splitting during evolution of H. sapiens sapiens lineage in Africa. If the ensoulment of the first homo occurred in the evolving populations of H. sapiens sapiens, then occasionally mixed couples (Neanderthals – Sa-piens or Denisovans – Sapiens) created relations that functioned as a family, in which children could have matured
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