Was Homo erectus the mysterious missing gene link?
Klevius predicts more and older dating Siberian
Some 100,000 years ago Neanderthal and other late archaic humans in Africa and Southwest Asia had reached a certain more or less even level of tool making and culture. However, only after some 40,000+ years ago we see the next huge jump in sophistication - and now only on a line from Altai to Central Europe. Nowhere else!
The Denisova genome reflects ancestry from people substantially different from Neanderthals and sub-Saharan Africans
A lack of diversity in the genetic material supports the view that Neanderthals lived in small groups in small populations.
Sex between closely related individuals within the Siberia Neanderthal community was common.
Pääbo: We can see that the mama and papa of the individuals were very closely related — half siblings or so. It is possible that the Altai Neanderthals were such a small population that they’ve hardly any other choice.
Neanderthal and modern human populations interbred too. The Neanderthal genome data confirms "leakage of DNA" from these extinct hominins into modern humans.
Klevius comment: As Klevius has said before the most likely scenario was Denisovan/human girls/women raped by Neanderthal males. Children from these meetings then came to be part of the human groups, hence spreading their new gene set up further.
Denisovans interbred with an unknown human lineage, getting as much as 2.7 to 5.8 percent of their genomes from it. This mystery relative apparently split from the ancestors of all modern humans, Neanderthals and Denisovans between 900,000 years and 4 million years ago, before these latter groups started diverging from each other.
Kay Prüfer, a computational geneticist at the Max Planck Institute for Evolutionary Anthropology: "Some unknown archaic DNA might have caught a ride through time by living on in Denisovans until we dug the individual up and sequenced it".
Interbreeding took place between Neanderthals and Denisovans and the research suggests at least 0.5 percent of the Denisovan genome came from Neanderthals.
There are more than 31,000 genetic changes that distinguish modern humans from Neanderthals and Denisovans. Some of them have to do with brain development.
A West Eurasian gene flow into the ancestors of Yoruba West Africans within the last ten thousand years has been detected, which indirectly contributed a small amount of Neandertal ancestry to Yoruba. The results, according to the researchers, mean that they have not identified any sub-Saharan African sample that they are confident has no evidence of back-to-Africa migration.
Klevius comment: So in summary we have a big-headed but dumb Denisovan related creature roaming the continent(s) while some of them ended up (or developed there) in the active and changing S E Asian jungle archipelago where they dwarfed without loosing intelligence (compare floresiensis). When some of these later managed to get to the mainland they again started mixing with their relatives all the way up to the really big headed northern Neanderthals in Altai.
The new brain then started a gene flow in all directions resulting in the pattern we now know.
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