Scientists Find Oldest Human DNA -- Evolution Timeline In Doubt

[Doc]

Baffling 400,000-Year-Old Clue to Human Origins http://graphics8.nytimes.com/images/2013/12/05/science/05dna-1/05dna-1-articleLarge.jpg Javier Trueba, Madrid Scientific Films
An artist's interpretation of the hominins that lived near the Sima de los Huesos cave in Spain.

By CARL ZIMMER Published: December 4, 2013 131 Comments (http://www.nytimes.com/2013/12/05/science/at-400000-years-oldest-human-dna-yet-found-raises-new-mysteries.html?partner=rss&emc=rss&smid=tw-nytimes&_r=0#commentsContainer) Scientists have found the oldest DNA evidence yet of humans’ biological history. But instead of neatly clarifying human evolution, the finding is adding new mysteries.



http://graphics8.nytimes.com/images/2013/12/05/science/05dna-3/05dna-3-articleInline.jpg
The thigh bone of a 400,000-year-old hominin from Sima de los Huesos, Spain.







In a paper in the journal Nature, scientists reported (http://tinyurl.com/lzae2ro) 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.


The mismatch between the anatomical and genetic evidence surprised the scientists, who are now rethinking human evolution over the past few hundred thousand years. It is possible, for example, that there are many extinct human populations that scientists have yet to discover. They might have interbred, swapping DNA. Scientists hope that further studies of extremely ancient human DNA will clarify the mystery.

Read the rest here: http://www.nytimes.com/2013/12/05/science/at-400000-years-oldest-human-dna-yet-found-raises-new-mysteries.html?partner=rss&emc=rss&smid=tw-nytimes&_r=0

[CasperParks]

Doc,

Thanks for posting. I read a similar article earlier at one of the major tv news networks. The article you posted is better done.

How many times in Earth's ancient history have disasters rebooted life?

The more we learn, the more we realize how much we don't know.

[Doc]

Doc,

Thanks for posting. I read a similar article earlier at one of the major tv news networks. The article you posted is better done.

How many times in Earth's ancient history have disasters rebooted life?

The more we learn, the more we realize how much we don't know.

There is a lot to this discovery that I will have to refresh my memory to understand the full significance. I remember the Denisovians go way back 200,000 years or more and we have their stone tools (which resemble the tools from Calico) but they were thought to be a dead end. Now, to find that they were in Spain so much earlier means they must have migrated earlier or had two migrations, East and West. Which means that what anthrpologists etc. believed about the human line and extinctions before finding this DNA was mistaken.

[Dragonfire]

Thanks for posting Doc. I read this earlier here - http://news.nationalgeographic.com/news/2013/12/131204-human-fossil-dna-spain-denisovan-cave/

[Doc]

Thanks for posting Doc. I read this earlier here - http://news.nationalgeographic.com/news/2013/12/131204-human-fossil-dna-spain-denisovan-cave/

Thanks! You're link has most of the details I was fuzzy about and there are links from that article to the rest of of the argument. The commenters at the NatGeo link do a good job of bringing out all the controversies in layman's terms, too. This is the kind of discovery that gets the textbooks questioned if not rewritten. 40 Years ago there is a good chance this inconvenient discovery might have been buried. Or we might have had to wait a year or five for a National Geographic Special on TV to know anything about this.

[southerncross]

I am always amazed but not surprised that such early life is found in Spain and France. The Lasceaux caves were just the beginning or discovery of our early times. No doubt they will push it back again with further discoveries. It opens up questions as to how sophisticated they were. Did they bury their dead in sacred sites ? What were their family and colony practices like ? What spiritual practices did they have ? It's just fascinating that we have so much in common with these early people.