The hard reality exists that hunting bands exchange women one way orthe other or they collect DNA from guests. In the event, DNA and newknow how traveled readily.
It appears at likely that the Neanderthal was the red haired giantthat shows up quite often. I would like to see that outright provenand there exists reports of actual living types in South America. Itat least appears to be possible.
So although pure neanderthal populations have essentiallydisappeared, their DNA has been absorbed into the larger populations. This is the ultimate fate of all small sub groups that areparticularly distinct. Again it is a boon for hybrid vigor.
The Real Question:Who Didn't Have Sex with Neanderthals?
By Charles Choi,LiveScience Contributor | LiveScience.com – Thu,Nov 1, 2012
http://news.yahoo.com/real-didnt-sex-neanderthals-134026418.html
The only modernhumans whose ancestors did not interbreed with Neanderthals areapparently sub-Saharan Africans, researchers say.
New findings suggestmodern North Africans carry genetic traces fromNeanderthals, modern humanity's closest known extinct relatives.
Although modern humansare the only surviving members of the human lineage, others onceroamed the Earth, including the Neanderthals. Genetic analysisof these extinct lineages’ fossils has revealed they once interbredwith our ancestors, with recent estimates suggesting that NeanderthalDNA made up 1 percent to 4 percent of modern Eurasian genomes.Although this sex apparently only rarely produced offspring,this mixing was enough to endow some people with the robustimmune systems they enjoy today.
The Neanderthal genomerevealed that people outside Africa share more genetic mutations withNeanderthals than Africans do. One possible explanation isthat modern humans interbred with Neanderthals mostly after themodern lineage began appearing outside Africa at least100,000 years ago. Another, more complex scenario is that an Africangroup ancestral to both Neanderthals and certain modern humanpopulations genetically split from other Africans beginning about230,000 years ago. This group then stayed genetically distinct untilit eventually left Africa.
To shed light on whyNeanderthals appear most closely related to people outside Africa,scientists analyzed North Africans. Some researchers had suggestedthese groups were the sources of the out-of-Africa migrations thatultimately spread humans around the globe.
The researchersfocused on 780,000 genetic variants in 125 peoplerepresenting seven different North African locations. They foundNorth Africans had dramatically more genetic variants linked withNeanderthals than sub-Saharan Africans did. The level of geneticvariants that North Africans share with Neanderthals is on par withthat seen in modern Eurasians.
The scientists alsofound this Neanderthal genetic signal was higher in North Africanpopulations whose ancestors had relatively little recentinterbreeding with modern Near Eastern or European peoples. Thatsuggests the signal came directly from ancient mixing withNeanderthals, and not recent interbreeding with other modern humanswhose ancestors might have interbred with Neanderthals. [10 Mysteriesof the First Humans]
"The only modernpopulations without Neanderthal admixture are the sub-Saharangroups," said researcher Carles Lalueza-Fox, a paleogeneticistat the Institute of Evolutionary Biology at Barcelona, Spain.
The researchers saytheir findings do not suggest that Neanderthals entered Africa andmade intimate contact with ancient North Africans. Rather, "whatwe are saying is that the contact took place outside Africa, likelyin the Near East, and that there was a back migration into Africa ofsome groups that peopled North Africa, likely replacing orassimilating some ancestral populations," Lalueza-Fox toldLiveScience.
This research alsosuggests that North African groups were not the source of theout-of-Africa migrations. Rather, other groups, perhaps out of EastAfrica, might have led this diaspora.
The scientistsdetailed their findings Oct. 17 in the journal PLoS ONE.
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