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The sequencing of the Neanderthal genome answered once and for all the question of whether these hominins played a role in the origins of modern humans—they did, and a majority of humans alive today retain a small portion of Neanderthal genes. This finding rejects the strictest versions of the Recent African Origin model and has been celebrated by supporters of Multiregional Evolution (MRE). However, we argue that MRE can also be rejected and that other, intermediate, models of modern human origins better represent the means by which modern humans became the only extant human species. We argue this because we reject one of the major tenets of MRE: global gene flow that prevents cladogenesis from occurring. First, using reconstructions of Pleistocene hominin census size, we maintain that populations were neither large nor dense enough to result in such high levels of gene flow across the Old World. Second, we use mammalian divergence and hybridization data to show that the emergence of Homo is recent enoug...

Since the 1984 discovery of the Nariokotome Homo erectus/Homo ergaster skeleton, it has been almost axiomatic that the emergence of Homo (sensu stricto) was characterized by an increase in body size to the modern human condition and an autapomorphic shift in body proportions to those found today. This was linked to a behavioral shift toward more intensive carnivory and wider ranging in the genus Homo. Recent fossil discoveries and reanalysis of the Nariokotome skeleton suggest a more complex evolutionary pattern. While early Homo tend to be larger than Australopithecus/Paranthropus, they were shorter on average than people today. Reanalysis of the Nariokotome pelvis along with the discovery of additional early and middle Pleistocene pelves indicate that a narrow bi-iliac (pelvic) breadth is an autapomorphy specific to Homo sapiens. Likewise, it appears that at least some early Homo (even those referred to H. ergaster/H. erectus) were characterized by higher humero-femoral indices than the H. sapiens avera...

Hennig differentiated parent‐offspring, or tokogenetic, relationships among organisms within a population, which are network‐like, or reticulate, in their structure, from phylogenetic relationships between species taxa, which are hierarchical. However, some biologists have recently argued that reticulation may occur across taxa at high taxonomic levels, and Jolly, using a papionin analogy for hominin evolution, argued that fossil hominins represent a group of allotaxa that likely exhibited varying degrees of hybridization in zones of ecological overlap. Such potential reticulation among the Hominini has important implications for phylogenetic reconstruction and is likely a significant source of homoplasy in the hominin fossil record. Hybridization between taxa can lead to the merging of taxa, to the reinforcement of behavioral barriers to mating, or even to the emergence of new, hybrid species. Templeton has noted that many mammalian species appear to be grouped into higher‐level, hybridizing taxa called ...

La fin du Pleistocene correspond a une importante modification ecologique en Europe, les plaines disparaissant au profit des forets, ce qui entraina a un changement radical de la faune avec une proliferation de petits animaux et l'extinction presque complete de nombreuses especes de grands mammiferes. L'un des changements probable dans les moyens de subsistance des hommes fut peut-etre alors l'intensification de la chasse au piege .