AI Study of Human Genome Finds Unknown Human Ancestor (smithsonianmag.com)

Zorro shares a report from the Smithsonian: A recent study used machine learning technology to analyze eight leading models of human origins and evolution, and the program identified evidence in the human genome of a "ghost population" of human ancestors. The analysis suggests that a previously unknown and long-extinct group of hominins interbred with Homo sapiens in Asia and Oceania somewhere along the long, winding road of human evolutionary history, leaving behind only fragmented traces in modern human DNA. The study, published in Nature Communications, is one of the first examples of how machine learning can help reveal clues to our own origins. By poring through vast amounts of genomic data left behind in fossilized bones and comparing it with DNA in modern humans, scientists can begin to fill in some of the many gaps of our species' evolutionary history. "The new data suggest that the mysterious hominin was likely descended from an admixture of Neanderthals and Denisovans (who were only identified as a unique species on the human family tree in 2010)," the report adds. "Such a species in our evolutionary past would look a lot like the fossil of a 90,000-year-old teenage girl from Siberia's Denisova cave. Her remains were described last summer as the only known example of a first-generation hybrid between the two species, with a Neanderthal mother and a Denisovan father."

Comments

Re:Species?

[dryeo]

There's at least 26 definitions of species. When you get down to it, defining a species is a problem. The observation of the AC about lions and tigers being able to hybridize with only one sex being fertile is an example that may apply to the different hominoids. There's also horses and donkeys where the offspring are almost always infertile but there has been rare cases of mules getting pregnant and producing offspring.
Ring species where the neigbours can breed but further apart specimens can't.
Plants get more complex. Dandelions IIRC skip generations so parent and offspring can't breed but grandparent and grandchild can.
Then there's the organisms that are asexual.