How many of us are the descendants of Neanderthals?

Question

And would we be able to find out whether we are by DNA testing?

Answer 1

So far the answer is 'zero', as they can't find any anomalous mitochondrial DNA that could have belonged to the Neanderthals. However, the jury is really still out on that one as it's easy to lose a DNA lineage.The later Neanderthal remains have chins and longer limbs, and some modern humans seem to have Neanderthal features, like occipital buns, long second toes, and a few others that are internal. The most probable answer is that they may well have made a small contribution to the European gene pool, mainly seen in our colouring, and Rhesus negative blood types.

Answer 2

Recent testing of Neanderthal DNA show that present day humans are not descended from the Neanderthals. This has placed them outside the human line of descent. However, it should be remembered that this has happened before, Neanderthals were out, only to be put back in.

There have been supposed hybrids found. The remains are few in number and when compared to the range of physical characteristics present in each species: "are either typically Neanderthal or modern (10) and, in one significant case, had been misdated ... that nobody has had any idea what a Neanderthal/modern hybrid might look like in theory"
http://www.pnas.org/cgi/content/full/96/13/7117

Recently a theory has been proposed that Neanderthal genes are somehow responsible for Autism in humans "however much of it being of an only circumstantial nature."
http://www.farviolet.com/~entropy/neanderthal/
The theory proposes that genes brought in by interbreeding have caused or contributed to Autism and ADHD. The challenge to this theory is that it's based primarily on assumptions of the Neanderthals. As example the lack of eye contact in Autistics is due to Neanderthal genes as "Although nothing is known about Neanderthal eye contact, lack of it is common in other primate species." One comparison: "Neanderthals had "rodeo-type" injuries, which might suggest they had different sensitivity to pain." is more likely due to what they hunters, reindeer and the techniques they used.

As one site reported "If this theory is correct, we would expect autism and ADHD to be disorders almost exclusive of European populations." due to the fact Neanderthals live primarily in Europe and not Asia or Africa. This is not the case.

While intriguing interbreeding hasn't been demonstrated. The DNA says separate species and supposed hybrids still fall into the physical variations found in each group.Disorders ascribes to Neanderthal genes, such as autism, rely on conjecture.

Answer 3

All or none. It is likely that a few Neanderthals may have had viable babies with humans. If so, then every human is descended from them, even blacks in Africa, Ed. It is highly unlikely that any human population has been completely isolated for over 50,000 years since modern humans first contacted Neanderthals.

Answer 4

I don't think this question is as dumb as it sounds.

I am unaware that science has determined, for certain, that old Neander and Cro Magnon ( a term used for the convenience of past anthropologists) could not have interbred. Logic dictates that if some lonely Neander came upon a winsome Cro Magnon female, alone and unprotected, he would be encouraged to...have his way with the hapless female.

If such a situation actually occurred, could a viable offspring result?

I can't say but possiblly science can and may have; I simply don't know.

So, are any of us descendants of such a union?

Good question, IMO!

Answer 5

To date we don't know if we have any Neandertal genes, but a complete sequencing of the Neandertal genome is targeted for a draft in slightly over a year. Many adhering to the "multi regional" hypothesis of sapien evolution believe Europeans mixed with Neandertal. To prove or disprove this hypothesis will require more extensive investigation.
Those supporting the Out of Africa "replacement" hypothesis point to MtDNA & Y chromosome markers as proof that sapiens have no Neandertal genes... but any indication of these markers could be wiped out in 3 generations. MtDNA is passed down only by female to daughter & Y is passed down only by a son. Therefore if a doner is female & has no daughters, that line disappears & the same can be said for a father that produces only daughters.
Bruce Lahn, John Hawks, Eric Trinkaus, Wolpoff & a number of others have gathered evidence on Neandertal hybrid fossiles & evidence of gene introgression by a more ancient line of human on the sapien line that migrated out of Africa.
Mungo man, found in Australia is at least 40,000 yrs old & the MtDNA tests as more like Neandertal than Sapien, although the skeleton "appears" to be a modern sapien. This may indicate mixing of Homo erectus & Sapien in South East Asia (Erectus appears to evolved into both Sapien & Neandertal.)
This makes for some very interesting reading:
http://donsmaps.com/mungo.html
You may also wish to google "John Hawks Neandertal genes"
To answer your question... yes we should soon know if sapien & neandertal produced fertile hybrids as many suspect. However, unless we obtain more DNA from H. erectus fossiles, we won't know if Asians have H. erectus genes.
BravoZul... We will have to disagree on your significant migration back to Africa hypothesis, as you have no supporting evidence & genetic evidence is not at all supportive of this.

Answer 6

I suggest you watch the Discovery Channel special "The Real Eve." It explains a lot.

Answer 7

They are still out on this one. That will just be another slot and another name for a missing link.

Answer 8

I'm leaning toward 80% based on some of the answers to some of the questions on YA.

Answer 9

OMG....my second toes are longer!!

Seriously, interesting discussion, I'm learning from the links provided. Thanks!