Posted on 05/18/2023 7:55:56 AM PDT by Red Badger
A new model for human evolution asserts that modern Homo sapiens stemmed from multiple genetically diverse populations across Africa rather than a single ancestral population. This conclusion was reached after researchers analyzed genetic data from present-day African populations, including 44 newly sequenced genomes from the Nama group of southern Africa. The research suggests that the earliest detectable split in early human populations occurred between 120,000 to 135,000 years ago, after long periods of genetic intermixing, and that subsequent migrations created a weakly structured genetic stem. Contrary to some previous models, this research implies that contributions from archaic hominins were unlikely to have significantly affected Homo sapiens’ evolution.
New model for human evolution suggests Homo sapiens arose from multiple closely related populations.
A new study in Nature challenges prevailing theories, suggesting that Homo sapiens evolved from multiple diverse populations across Africa, with the earliest detectable split occurring 120,000-135,000 years ago, after prolonged periods of genetic intermixing.
In testing the genetic material of current populations in Africa and comparing it against existing fossil evidence of early Homo sapiens populations there, researchers have uncovered a new model of human evolution — overturning previous beliefs that a single African population gave rise to all humans. The new research was published on May 17, in the journal Nature.
Although it is widely understood that Homo sapiens originated in Africa, uncertainty surrounds how branches of human evolution diverged and how people migrated across the continent, said Brenna Henn, professor of anthropology and the Genome Center at UC Davis, corresponding author of the research.
Village of Kuboes
View of the village of Kuboes, on the border of South Africa and Namibia. DNA samples were collected from Nama individuals who have historically lived in the region. Credit: Brenna Henn/UC Davis
“This uncertainty is due to limited fossil and ancient genomic data, and to the fact that the fossil record does not always align with expectations from models built using modern DNA,” she said. “This new research changes the origin of species.”
Research co-led by Henn and Simon Gravel of McGill University tested a range of competing models of evolution and migration across Africa proposed in the paleoanthropological and genetics literature, incorporating population genome data from southern, eastern, and western Africa.
Nama Woman
Nama woman standing in the doorway to her home in Kuboes, South Africa, a UNESCO World Heritage Site. Credit: Justin Myrick-Tarrant/with permission
The authors included newly sequenced genomes from 44 modern Nama individuals from southern Africa, an Indigenous population known to carry exceptional levels of genetic diversity compared to other modern groups. Researchers generated genetic data by collecting saliva samples from modern individuals going about their everyday business in their villages between 2012 and 2015.
The model suggests the earliest population split among early humans that is detectable in contemporary populations occurred 120,000 to 135,000 years ago, after two or more weakly genetically differentiated Homo populations had been mixing for hundreds of thousands of years. After the population split, people still migrated between the stem populations, creating a weakly structured stem. This offers a better explanation of genetic variation among individual humans and human groups than do previous models, the authors suggest.
“We are presenting something that people had never even tested before,” Henn said of the research. “This moves anthropological science significantly forward.”
“Previous more complicated models proposed contributions from archaic hominins, but this model indicates otherwise,” said co-author Tim Weaver, UC Davis professor of anthropology. He has expertise in what early human fossils looked like and provided comparative research for the study.
The authors predict that, according to this model, 1-4% of genetic differentiation among contemporary human populations can be attributed to variation in the stem populations. This model may have important consequences for the interpretation of the fossil record. Owing to migration between the branches, these multiple lineages were probably morphologically similar, which means morphologically divergent hominid fossils (such as Homo naledi) are unlikely to represent branches that contributed to the evolution of Homo sapiens, the authors said.
Reference: “A weakly structured stem for human origins in Africa” by Aaron P. Ragsdale, Timothy D. Weaver, Elizabeth G. Atkinson, Eileen G. Hoal, Marlo Möller, Brenna M. Henn and Simon Gravel, 17 May 2023, Nature. DOI: 10.1038/s41586-023-06055-y
Additional co-authors include Aaron Ragsdale, University of Wisconsin, Madison; Elizabeth Atkinson, Baylor College of Medicine; and Eileen Hoal and Marlo Möller, Stellenbosch University, South Africa.
So, we didn’t descend from apes or chimps or whatever BS they claim?!?
All the white people left Africa 500,000 year sago....................
Great joke.
No, no it doesn’t change the origin of human species.
Mankind was created in the image of God.
Thus endeth the lesson.
That’s what it sounds like. Hoo rah?
Who writes this garbage?
In 6th grade, if I had repeated the same sentence over and over again, and tried to pass it off as a composition, I would have gotten an F.
An Eff? Uh oh! ;-)
[[What do you mean ‘we’, Paleface?........................]]
I identify as a melanin deficient minority person thank you very much
Very interesting. It never seemed logical to me that the one-and-done out of Africa dogma was factually based-there had to be more than one tribe/group making that migration over centuries, a group going here, a group going there, etc-I’m sure humans have always been curious to see what kind of places and stuff were available on the other side of the mountains/water and were smart/inventive enough to get there-the Supreme Being-God designed us that way for long-term survival. Trade probably started to be the driving force as soon as one group of folks found new stuff to trade and new people to do business and breed with. The woman in the photo looks like Polynesian people I’ve met-from Australia, Hawaii, etc-sort of blows that all-Black Africa/Wakanda thing away...
This is great news! We are now ALL African-Americans and can claim reparations which are for those of African-American descent not just for the descendants of American slaves.
“Lucy was a tranny?”
And now she’s sad ‘cause she ain’t the Ma of us all now. Just another case of whitey keepin’ a sistah down!
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