And yes, another post on archaic hominin introgression into modern humans in Africa: Yorubans have admixed with an unknown hominin and this gave them archaic genes. So much for the "diversity" of Sub Saharan Africans as proof of them being ancestral to the rest of human beings.
This paper: Recovering signals of ghost archaic admixture in the genomes of present-day Africans, by Arun Durvasula and Sriram Sankararaman - doi: https://doi.org/10.1101/285734 - says that:
"Yoruban individuals trace about 7.9% of their genomes to an as yet unidentified archaic population."
An eight percent of their genes are archaic far more than the Neanderthal admixture in Eurasians or the Denisovan introgression into non-Africans... This is really a "Big" introgression and that explains why they, the Africans are so different and "diverse" from non-Africans. They mixed with diverse ancient genes of some unknown hominin. So they aren't older than us, they simply "admixed" with archaic hominins.
The authors add:
"suggesting that there was a rich diversity of hominin species within Africa
and that introgression was commonplace. Using our inferred segments of archaic ancestry in the Yoruba, we find that there are regions of the genome that are under higher selective constraint have reduced archaic ancestry on average indicating that the archaic alleles were deleterious in the hybrid population. More data is needed for a complete picture of these ghost populations. For example, it is unclear whether the archaic signatures found here are from the same as those found in other African populations"
....
"...Taken together, these results suggest that introgression from one or more deeply diverged populations
278 has shaped the genomes of a modern human population in Africa."
And no, these ancient genes didn't come from mixing with Pygmies. The authors found evidence "...suggesting that the Biaka are not the source of admixture"
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2018 by Austin Whittall ©
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