But this gene pool stuff is really important. Homo Sapiens are a very diverse group and IMHO we 'hard wired' that way. I can tell you from my personal experience that whenever I seem some foreign chick I've always wanted to see what's in those jeans genes.
I didn't mean to imply intermarriage between neandertal and cro-magnon..
What I meant was, neandertal, being isolationist and territorial, tended to be suspicious of even their own kind..
Intermarriage between neandertal tribes was therefore, fairly uncommon, possibly with the exception of females captured during clashes between tribes.
Their natural tendencies helped to cause their demise..
They stayed in their own territories and defended them from outsiders, even among their own species..
I expect the introduction of Cro-Mag made them even more insular..
Cro-Magnon, on the other hand, while they had their tribal clashes, also seemed to have found room for "nuetral ground", for gatherings, trade, etc.. ( and maybe a little wife-swapping, or other trading in females, be it on a simple barter basis, mutual interest like tribal alliances, or whatever.. )