Other primates would have existed at the time, too, but not all were ancestors of ours.
The divergence date has been a matter of hot debate at least since the publication in 1859 of Charles Darwin's "The Origin of Species." The new estimate supports claims that recently discovered primate fossils, the Millennium man (.
The new estimate fails to square up with previous molecular estimates for the divergence date, not to mention the fossil evidence on hominids, said Ian Tattersall, a paleoanthropologist at the American Museum of Natural History.
"You have bipedal hominids by 4 million years ago, and 4.2 million years ago you have definite fossil evidence of bipeds around the place, part of a knee joint and a lower ankle joint that are pretty good indicators," Tattersall told .
Asger Hobolth of North Carolina State University and his colleagues arrived at the new estimate of " the time we became human," or the time in the past when descendents of the human-chimp ancestor split into human and chimp, by statistically comparing DNA from four regions of the human, chimp and gorilla genomes.
The timeline of human evolution is long and controversial, with significant gaps.
"And then you have more arguable fragmentary back 6 million years ago." "Chimps are knuckle-walkers and hominids are bipeds," he said, "and it's inconceivable that you could have a common ancestor to both at 4 million years ago when you already have evidence in the hominid lineage that there were bipeds already around at that time." Robin Lloyd was a senior editor at and Live Science from 2007 to 2009.
Strange then, I realised recently, that I have rarely been properly on my own.
The team also came up with a fairly large estimate for the size of the ancestral population of the primates just before human and chimp species evolved from it—about 65,000 individuals. degree in sociology from the University of California at Santa Barbara.The lineages of humans and chimpanzees, our closest relatives, diverged from one another about 4.1 million years ago, according to a new estimate that is said to be far more precise than previous ranges for this critical evolutionary moment.However, the claim is a bad match with previous estimates based on fossil evidence and other genetic work.I haven’t lived with a boyfriend, introduced anyone to my parents, or been on a mini-break.
Experts do not agree on many of the start and end points of various species. The new divergence date is considered fairly recent, maybe too much so.Previous estimates, based on fossil evidence, put the most recent common ancestor of humans and chimps on Earth anywhere from 2 million to 10 million years ago, Hobolth said.