At what point is the theory just wrong?
Having to adjust the parameters of the model and having to change the fundamental aspects (e.g. humans came from Africa) are different things.
Right/wrong is most commonly used in a moral framework. Correct/incorrect seems more apt during application of an observed value to an expected value.
We live in a fascinating time!
From the article
Razib Khan had a good short primer on this topic a little while back [1], excerpt:
The data for non-Africans is rather unequivocal. The vast majority of (>90%) of the ancestry of non-Africans seems to go back to a small number of common ancestors ~60,000 years ago. Perhaps in the range of ~1,000 individuals. These individuals seem to be a node within a phylogenetic tree where all the other branches are occupied by African populations. Between this period and ~15,000 years ago these non-Africans underwent a massive range expansion, until modern humans were present on all continents except Antarctica. Additionally, after the Holocene some of these non-African groups also experienced huge population growth due to intensive agricultural practice.
To give a sense of what I’m getting at, the bottleneck and common ancestry of non-Africans goes back ~60,000 years, but the shared ancestry of Khoisan peoples and non-Khoisan peoples goes back ~150,000-200,000 years. A major lacunae of the current discussion is that often the dynamics which characterize non-Africans are assumed to be applicable to Africans. But they are not.
[1] https://www.gnxp.com/WordPress/2017/04/28/beyond-out-of-afri...
And of course on these time scales people can easily walk all over the place. We only see remnants of larger populations lone wanderers are extremely unlikely to leave any evidence behind.
If you are reading experts still standing behind a simplistic Out of Africa model after all the recent findings of archaic admixture and incredibly deep splits in human populations, I'd be very curious to see some links to papers/articles.
[1] https://medium.com/@johnhawks/the-story-of-modern-human-orig...
[2] https://www.edge.org/conversation/christopher_stringer-rethi...
I thought The Selfish Gene would be this, but it seemed primarily focused on more abstract/philosophical questions, like group selection vs. gene selection. I'm more interested in concrete information about what our DNA and the fossil record can credibly establish. I want to know what facts are indisputably known, and which are more speculative.
So far, nobody has recovered ancient DNA from archaic human skeletal remains in Africa. The 2000-year-old Ballito Bay boy is not the oldest, but there are no DNA results from truly archaic specimens, like the Kabwe skull from Zambia. As a result, we don’t have the kind of record within Africa that geneticists have built for Neanderthals and Denisovans in Eurasia...
Morphology does not tell the story of modern human origins...Did short faces and rounded braincases really make a difference to the survival and success of modern humans? Maybe they were chance legacies of the population that gave rise to our gene pool. We don’t know.
Conclusion:
We have to discover more fossils. That’s the way that we will start to solve these new problems and shed light on old mysteries.
[1] https://medium.com/@johnhawks/the-story-of-modern-human-orig... via https://news.ycombinator.com/item?id=16234903
https://www.youtube.com/watch?v=dGiQaabX3_o
https://www.youtube.com/watch?v=czgOWmtGVGs
His stuff is well sourced and generally reliable.
This happened "after the Holocene"? Aren't we in the Holocene epoch?
And, indeed, a quick search for Razib Khan brings up this: https://undark.org/article/race-science-razib-khan-racism/
