the detailed patterns of genomic variation can be accurately fitted to a model where the lineage ancestral to Khoe-San populations diverged around 300,000 years ago from a lineage ancestral to rainforest hunter-gatherers and neighboring agriculturalists.
So this earlier paper shows a similar split 300,000 years ago
Ancient tree-topologies and gene-flow processes among human lineages in Africa
e investigated genomic diversity patterns and aimed at reconstructing ancient demographic histories among lineages having led to different groups of Khoe-San hunter-gatherer or herder populations from Southern Africa 6, and to different groups of both Eastern or Western Congo Basin hunter-gatherer populations (often historically designated “Pygmies” by Europeans)
Interestingly, we found strong indications for almost synchronic events of introgressions having occurred during the Last Interglacial Maximum in Africa 67, between ~90,000 and ~135,000 years ago (when considering 20 or 30 years per generation). They involved gene-flow between lineages ancestral to Khoe-San populations and ancestors of Rainforest Hunter-Gatherer neighbors on the one hand and on the other hand, between lineages ancestral to Khoe-San populations and the lineage ancestral to all
Rainforest Hunter-Gatherers. An increase in material-based culture diversification and innovation, possibly linked to climatic and environmental changes locally, has previously been observed durin this period of the Middle Stone Age in diverse regions of continental Africa; prompting a long-standing debate as to its causes if human populations were subdivided and isolated biologically and culturally at the time.
https://academic.oup.com/hmg/article/30/R1/R2/6089116
The human Neandertal/Denisovan divergence of some 650 000 years into the past can then be viewed as an upper bound of the development of unique features of Homo sapiens. In other words, by using these constraints, we can ask the question how humans developed unique characteristics from the time of the common ancestor of Neandertals/Denisovans till the starting time of human stratification observed today.
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