Today I have come across two brand new and very interesting papers:
The first one tells us that modern Homo sapiens reached Australia much earlier than formerly believed: 65,000 years ago. (Chris Clarkson et al., "Human occupation of northern Australia by 65,000 years ago", Nature 547, 306–310, 20 July 2017, doi:10.1038/nature22968).
The authors point out that "This evidence sets a new minimum age for the arrival of humans in Australia, the dispersal of modern humans out of Africa, and the subsequent interactions of modern humans with Neanderthals and Denisovans.".
The other paper by Duo Xu et al ("Archaic hominin introgression in Africa contributes to functional salivary MUC7 genetic variation", Molecular Biology and Evolution, 2017; DOI: 10.1093/molbev/msx206.) tells us that an archaic hominin interbred with sub-Saharan Africans.
This is an extremely interesting conjecture which the authors state as follows "...we conclude that a divergent MUC7 haplotype likely originated in an unknown African hominin population and introgressed into ancestors of modern Africans...".
This introgression could explain why there is so much diversity in sub-Saharan Africans: they got it from an archaic human (I posted this same idea Here, where I wrote: "This leads me to ask, what if African heterozygosity was enriched by recent admixture with other hominins in Africa? an inflow of different relic alleles elevated African diversity above that of non-Africans" and Here where I wrote: "These ancient African humans carried the A00 lineage in them, mated with AMH (within the last 195 ky)").
The second paper is interesting and I will post on it later because it has some "orthodoxy" influencing its hypothesis, see this for instance, where the authors look into the introgressed halpogroup, (E):
"However, introgression of haplogroup E from Neanderthals or Denisovans is unlikely, because haplogroup E is exclusively found in sub- Saharan African populations, whereas introgression events between Neanderthals or Denisovans with modern humans happened after modern humans migrated out of Africa (Vernot and Akey 2014) (Figure 5A, Figure S5). As such, we hypothesize that an archaic hominin, at that time still roaming in Africa, contributed haplogroup E to the ancestors of extant Africans."
They are assuming that H. sapiens originated in Africa and moved "Out" of Africa. If they had move "Into" Africa from Eurasia, then Neanderthals or Denisovans could have been the origin of the haplogroup...
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2014 by Austin Whittall ©
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