Figure 1: A possible model of archaic introgression based on the latest analysis using second-generation sequencing.
Journal name: Nature Reviews Genetics Volume: 15, Pages: 149–162 Published (2014)
Red arrows indicate initial colonization events across the Old World after the origination of anatomically modern humans (AMHs) in Africa, including two movements into Asia. Approximate positions of introgression events are represented by coloured circles and are not intended to be accurate. This model portrays the hypothesis that portions of the Denisovan genome entered the human gene pool through hybridization with more widespread populations of archaic hominins (such as Homo erectus), which also interbred with the Denisovan population. Models that involve interbreeding directly between Denisovans and AMHs (anatomically modern humans) can be found in Ref. 46. The black arrow shows a more recent expansion of Asian farming populations (that is, <10,000 years ago) that did not carry introgressed Denisovan alleles and that replaced much of the indigenous resident population up to Wallace’s phenotypic boundary (shown by the dashed line), which lies just east of Wallace’s biogeographical line154
This hypothesis may explain the lack of evidence for Denisovan introgression outside islands in Southeast Asia and Oceania.
Figure 2: Alternative human origin models that fit existing fossil evidence on the basis of either phylogenetic or pedigree-based mutation rates.
Figure 3: Second-generation sequencing in ancient Europeans.
a | The map of Europe shows the major prehistoric migration events that may have influenced modern-day European genetic diversity. These events, in chronological order, are the initial colonization of Europe ~40,000 years ago…
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