Re: Research finds that Homo sapiens may be a hybridogenous species.

On 3/23/2025 11:10 AM, Ernest Major wrote:

A paper in Nature Genetics infers that two lineages split c. 1.5 million years ago, and that c. 300,000 year ago hybridisation produced a population ancestral to modern humans, with 80% of its ancestry from one lineage, and 20% from the other.
 https://www.nature.com/articles/s41588-025-02117-1#MOESM2
 

There was a previous paper that was mainly about how Neanderthals looked more related to modern humans than Denisovans due to an interbreeding event 250,000 years ago between Africans and Neanderthals.  Their analysis indicated that there were two populations that coexisted with the lineage that gave rise to the Neanderthal-Denisovan and Africans that separated from each other over a million years ago and that this lineage either came back to Africa or was preserved somewhere in Africa and interbred with the African lineage before modern humans left Africa. It was their best model for what genetics left Africa and how it differed from what had left 200,000 years earlier.  They did not know where this second population of Homo evolved only that it must have been kept separate from the African lineage for more than a million years. This paper must be expanding on that initial inference from the sequence.  They are talking about two populations of Homo erectus that would have coexisted for over a million years getting back together and interbreeding to produce the Africans that left Africa 60,000 years ago.
My guess would be that some Homo erectus left Africa over a million years ago, and some of them came back before they were displaced by the Neanderthals and Denisovans.  The Denisovan genomes show evidence that they interbred with, possibly, Homo erectus in South East Asia that were known to have colonized Indonesia before the Denisovans (think about Java man).
Ron Okimoto