Nice find.  That was interesting...

Here's an interesting new discovery:

http://johnhawks.net/weblog/reviews/neandertals/neandertal_dna/denisova-krause-2010.html

Basically, they've found a mitochondrial strain in a Siberian finger bone that diverged from the human strain approximately 1,000,000 years ago.  Humans and known neanderthals are on the same side of the divergence, although neanderthals were known to live in the same general area at the time the bone was deposited.

See the blog post and the papers it links to for more information.

A belated update - the paper is now available:

http://www.sciencemag.org/cgi/content/abstract/328/5979/710

There's a good discussion here:

http://johnhawks.net/weblog/reviews/neandertals/neandertal_dna/neandertals-live-genome-sequencing-2010.html

Bottom line:  nonafrican humans have 1% to 4% more neanderthal blood than african humans, meaning that nonafrican humans have at least 1% to 4% neanderthal blood.  The important part of the finding is that it's not 0%.

A belated update - the paper is now available:

http://www.sciencemag.org/cgi/content/abstract/328/5979/710

There's a good discussion here:

http://johnhawks.net/weblog/reviews/neandertals/neandertal_dna/neandertals-live-genome-sequencing-2010.html

Bottom line:  nonafrican humans have 1% to 4% more neanderthal blood than african humans, meaning that nonafrican humans have at least 1% to 4% neanderthal blood.  The important part of the finding is that it's not 0%.

So, are you saying that decendants of northern Europeans/somewhere else? could possess a significant amount of neanderthal DNA, such that one's physiology would be more like a neanderthal?

That actually makes sense. Makes me think even more about a mostly meat diet. Might even explain why nonafricans tend to be hairier.

And I come from people from the middle east by way of eastern Europe (Jewish).  I look like every other Mediterannean and Levantine ethnicity - people ask if I am whatever they are (Italian, Spanish, Arab, Turk, etc.)  I am short, stocky, hairy, etc.  I don't know, but I suspect so-called racial characteristics are relatively modern traits as people became more concentrated in particular areas rather than nomadic or even pastoral.

And I come from people from the middle east by way of eastern Europe (Jewish).  I look like every other Mediterannean and Levantine ethnicity - people ask if I am whatever they are (Italian, Spanish, Arab, Turk, etc.  I am short, stocky, hairy, etc.  I don't know, but I suspect so-called racial characteristics are relatively modern traits as people became more concentrated in particular areas rather than nomadic or even pastoral.

You count as nonafrican for the purposes of the genetic findings I linked to.

Given the 1%-4% was found in east Asians as well as Europeans, it seems most likely that the relevant hybridization occurred in the middle east, when our nonneanderthal ancestors left Africa and encountered the neanderthals that then lived in the middle east.  That conjecture seems further bolstered by the fact that many middle eastern skeletons from that period a few tens of thousands of years ago seem to be intermediate between neanderthal and cro magnon forms.

Whether humans in more northerly parts of Europe have more neanderthal ancestry from further interbreeding is not yet known.  Partial genetic analysis of two neanderthals from further north indicate that they had lighter coloration, with perhaps red hair, but it was from an allele not found in the modern human population, so the lightening of complexion further north in Europe may be parallel adaptation.  We simply don't have enough information to know yet.

What I found most interesting was that east Asians also had neanderthal ancestry, since previous to this east Asians had been shown only to have significant amounts of likely Asian homo erectus ancestry not shared by Europeans or Africans.  That's what makes it most likely that the neanderthal hybridization occurred in the middle east, since on the path from Africa to the far East, neanderthals weren't found east of the middle east.