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Jovialis
22-07-17, 16:30
http://www.buffalo.edu/news/releases/2017/07/028.html

By Charlotte Hsu


Release Date: July 21, 2017


“It seems that interbreeding between different early hominin species is not the exception — it’s the norm.”
Omer Gokcumen, assistant professor
Department of Biological Sciences
BUFFALO, N.Y. — In saliva, scientists have found hints that a “ghost” species of archaic humans may have contributed genetic material to ancestors of people living in Sub-Saharan Africa today.

...

“Based on our analysis, the most plausible explanation for this extreme variation is archaic introgression — the introduction of genetic material from a ‘ghost’ species of ancient hominins,” Gokcumen says. “This unknown human relative could be a species that has been discovered, such as a subspecies of Homo erectus, or an undiscovered hominin. We call it a ‘ghost’ species because we don’t have the fossils.”


It's called a ghost species, because there's no fossil evidence. But by using saliva samples of modern Sub-Saharan Africans, scientists found signs of admixture with an archaic ghost species. There are indications that Homo sapiens in Africa interbred with another unknown ancient hominid, or perhaps a known subspecies of Homo erectus.



More from the article (http://www.buffalo.edu/news/releases/2017/07/028.html)

A tantalizing clue in saliva


The scientists came upon their findings while researching the purpose and origins of the MUC7 protein, which helps give spit its slimy consistency and binds to microbes, potentially helping to rid the body of disease-causing bacteria.


As part of this investigation, the team examined the MUC7 gene in more than 2,500 modern human genomes. The analysis yielded a surprise: A group of genomes from Sub-Saharan Africa had a version of the gene that was wildly different from versions found in other modern humans.


The Sub-Saharan variant was so distinctive that Neanderthal and Denisovan MUC7 genes matched more closely with those of other modern humans than the Sub-Saharan outlier did.

LeBrok
22-07-17, 16:54
It makes sense. Hominid species are known of mixing and remixing with each other.

bicicleur
22-07-17, 18:33
not only in Africa
it is the most plausible explanation for 'Basal Eurasian'

Jovialis
22-07-17, 19:34
not only in Africa
it is the most plausible explanation for 'Basal Eurasian'

Do you mean that Basal Eurasians are the common ancestor, that bridges all modern Homo Sapiens? Who are mixed with other hominids (Neanderthals, denisovans, or this ghost population)?

There are probably other archaic ghost species that live on in the genes in different areas of the world.

bicicleur
23-07-17, 08:41
Do you mean that Basal Eurasians are the common ancestor, that bridges all modern Homo Sapiens? Who are mixed with other hominids (Neanderthals, denisovans, or this ghost population)?

There are probably other archaic ghost species that live on in the genes in different areas of the world.

I think there was an earlier wave of modern humans out of Africa, of which Y-DNA and mtDNA are extinct, but which autosomal contributed to Basal Eurasian.
I refer to the tools found at Jebel Faya 129 ka, and the recent findings in northern Australia, 65 ka.
Basal Eurasian branches of between African and Usht-Ishim.