Whole Genome Sequencing / Archaic Interbreeding

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Figure 1: A possible model of archaic introgression based on the latest analysis using second-generation sequencing.

From The impact of whole-genome sequencing on the reconstruction of human population history

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.

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Figure 2: Alternative human origin models that fit existing fossil evidence on the basis of either phylogenetic or pedigree-based mutation rates.

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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…

More at link above.

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2 thoughts on “Whole Genome Sequencing / Archaic Interbreeding

  1. I want to add something to the map:

    The red darts show from where modern humans (HS) migrated out of Africa. I think we can never be sure if the violet filled areas do not represent Homo Erectus. What would they be else instead of named as Archaic Africans?

    I read about Homo Erectus instead of Archaic Africans. You can add Homo Rhodeniensis to that archaic group, too. But the most important species was H.E. because he not only contributed to the evolution of HS but also to Homo Erectus Heidelbergensis/ Homo Heidelbergensis! He then evolved into Neandertaler.

    Archaic Africans are named as Palae Africans and were represented in my opinion by tropical Homo Erectus branches.

    If you move on the map to East Asia you find the grey filled areas representig Homo Erectus habitat. I find that confusing because in Africa you had them at first, but then some tropical Homo Erectus populations of better intelligence than neighboured populations migrated to East Asia and evolved there special features but also kept features they already had from Africa. If you think of South East Asia with its tropical climate you know curly hair was a better adaption than straight hair.

    Homo Erectus did not leave Africa complete.

    When Homo Sapiens was entering the stage in todays Ethiopia he must have met Homo Erectus and interbreed with them.
    The same situation took place in East Asia.

    So you not only have HS migrating out from Africa to parts of the world but also HS-HE hybrids migrating to East Asia. And then interbreeding with a earlier form of HE there.

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    • Thanks for the comment! I’m an H. erectus fan. Enter ‘erectus’ in the search box for my blog; several erelated posts will appear. I contend that WE ARE H. erectus – Neanderthals, H.Sapiens and Modern Social humans are all “types”: (subspecies that were on the path toward speciation) but our wandering ways ensured interbreeding. Modern Social Humans (neurotypicals) are very recent and highly juvenalized (neotenic) H. erectus. MSH are likely an “invasive species”…

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