[The Final Dakar]

http://www.nytimes.com/2013/12/05/sc...mysteries.html

Mind-boggling number. And for extra fun, it pretty much muddles up a lot of theories on human evolution and identification of bones.

In a paper in the journal Nature, scientists reported Wednesday that they had retrieved ancient human DNA from a fossil dating back about 400,000 years, shattering the previous record of 100,000 years.

The fossil, a thigh bone found in Spain, had previously seemed to many experts to belong to a forerunner of Neanderthals. But its DNA tells a very different story. It most closely resembles DNA from an enigmatic lineage of humans known as Denisovans. Until now, Denisovans were known only from DNA retrieved from 80,000-year-old remains in Siberia, 4,000 miles east of where the new DNA was found.

But the DNA did not match that of Neanderthals. Dr. Meyer then compared it to the DNA of the Denisovans, the ancient human lineage that he and his colleagues had discovered in Siberia in 2010. He was shocked to find that it was similar.

“Everybody had a hard time believing it at first,” Dr. Meyer said. “So we generated more and more data to nail it down.”

The extra research confirmed that the DNA belonged on the Denisovan branch of the human family tree.

The new finding is hard to reconcile with the picture of human evolution that has been emerging based on fossils and ancient DNA. Denisovans were believed to be limited to East Asia, and they were not thought to look so Neanderthal-like.

To me the obvious answer is Denisovans are actual future humans with time travel technology, who keep getting trapped in the past and having their bones dug up now.

Based on previously discovered ancient DNA and fossil evidence, scientists generally agreed that humans’ direct ancestors shared a common ancestor with Neanderthals and Denisovans that lived about half a million years ago in Africa.

Their shared ancestors split off from humans’ lineage and left Africa, then split further into the Denisovans and Neanderthals about 300,000 years ago. The evidence suggested that Neanderthals headed west, toward Europe, and that the Denisovans moved east.

Humans’ ancestors, meanwhile, stayed in Africa, giving rise to Homo sapiens about 200,000 years ago. Humans then expanded from Africa into Asia and Europe about 60,000 years ago. They then interbred not only with Neanderthals, but with Denisovans, too. Later, both the Denisovans and Neanderthals became extinct.

“Now we have to rethink the whole story,” Dr. Arsuaga said.

Dr. Arsuaga doubts that Denisovans were spread out across so much of the Old World, from Spain to Siberia, masquerading as Neanderthals.

One alternative explanation is that the humans of Sima de los Huesos were not true Neanderthals, but belonged to the ancestors of both Denisovans and Neanderthals.

It is also possible that the newly discovered DNA was passed to both Neanderthals and Denisovans, but eventually disappeared from Neanderthals, replaced by other variants.

[osiris]

News about inter-species mating really adds to the fun.

Any (honest) genome scientist will profess a 90% lack of understanding* with the numbers they see - profound, really. Anything is possible!

edit: * gaps in DNA sequences, for one.

[The Final Dakar]

It's amusing that early homo sapiens seem to have ****ed everything they came in contact with – and may have caused extinction through fornication.

[osiris]

Originally Posted by The Final Dakar 

It's amusing that early homo sapiens seem to have ****ed everything they came in contact with – and may have caused extinction through fornication.

lol quite true. But thankfully they did because we're the end result.
Well, some of us.