What has happened in the field of human evolution in the last 25 years can be summed up in one word: “more”. Archaeologists have found many more fossils, species and artifacts in more places – from tiny “hobbits” that lived on an Indonesian island to mysterious Homo naledi known only from a single deep cave in South Africa. At the same time, researchers have developed more and better techniques for analyzing all these remains. There is, simply put, a vast amount of information about our ancestry and extinct cousins.
Two main lessons emerged from this blizzard of discoveries. First, since 2000, the hominin fossil record has been extended much further into the past. In the late 1990s, he was the oldest known hominin 4.4 million years old Ardipithecus. But in 2000 and 2001, scientists found even older ones Ardipithecus, Orrorin tugenensis from 6 million years ago and Sahelanthropus tchadensis from 7 million years ago. According to Terror species, Orrorin praegenswas quietly described in 2022; appears to be slightly newer than O. tugenensis.
The discovery of these early hominins was “one of the great revolutions”, he says Clement Zanolli at the University of Bordeaux in France.
Second, the story of our own species’ emergence from the hominin pack has become much richer. By the year 2000 genetic evidence proved that all non-African people descended from African ancestors who lived about 60,000 years ago. The consequence was that modern humans evolved in Africa and expanded from there to replace all other hominin species.
But in 2010, scientists sequenced the first Neanderthal genome, followed by the DNA of many other ancient humans. DNA revealed that our species interbred with Neanderthals, Denisovans, and possibly others—and that other groups sometimes intermingled.
Scientists who study skeletons have long suspected interbreeding because many fossils don’t fit neatly into species categories, he says Sheela Athreya at Texas A&M University in College Station. Jaws from Peştera cu Oase, Romania, were described by Erik Trinkaus and colleagues in 2003 as a hybrid of man and Neanderthalbased on its shape. “[Trinkaus] was called a crackpot,” says Athreya. Then in 2015, genetics revealed that the Oase individual had a Neanderthal ancestor four to six generations earlier.
So our species did not simply expand out of Africa. Instead, our population absorbed the genetic heritage of Neanderthals and Denisovans along the way. Genetically, we are a mosaic: the stitched together remnants of millions of years of different forms of humanity.
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