http://dienekes.blogspot.com/2012/10/neandertal-modern-hybrid-babies-and.html

35. “You give me woolly rhinocerous liver, I love you long time.” LOL

The trend definitely seems to be going in the direction of “hybrids” all over the world. Certain places, like Hawaii and other parts of America, Brazil, Macau have been like this for a while. These days I see more and more mixed couples and mixed children. As an aside, I feel kinda weird using the word “hybrid” like we’re talking about cross-pollinating orchids, or breeding dogs or something. But then again, we’re animals too. It’s not that weird. I don’t like to deify humans.

Hybrid zones do still happen too, among a lot of first generation hybrids – restaurants, bars, chat-rooms and stuff. There are schools here where about a 2/3 majority (not an exaggeration) of the students are first generation hybrids.

I still haven’t seen any totally convincing evidence for a significant difference in pelvis size by race, such that it would lead to more c-sections. If 100 couples of comparably sized Asian females and white males – say both partners are around 5’6″ – had children, would the c-section rate be above average? I doubt it. But that’s just a gut feeling. And I think when it comes to possible rape being involved, a homo sapien male would have managed even against a neanderthal. But who knows, they might have just been into it. There were probably few to no social constraints back then about that kind of thing.

Maybe there was a hybrid zone, where people could find others who were not too different from them selves

It’s moot in any case – some fertile hybrids apparently did survive, unless what we’re seeing is ancient population structure in SSA, and the evidence seems to be moving away from that (and considering that hybridisation with Denisovans evidently also did occur). I was just trying to explain why past doubts about Hsn/Hss hybridisation were not necessarily a result of political correctness or the ‘grossness’ factor. If the ‘grossness’ factor had any relevance, a substantial subset of people in America, Australia, UK and Mexico would no longer be reproducing, which is obviously not the case.

Of course there’s always the ‘hello sailor’ factor.

Wait what about Hss males and Hsn females? They may have had easier births than they usually would have.

try and make this discussion useful, instead of randomly firing weird and confusing assertions.

Also, what were their ethnicities? “Asian” covers everything from India to Tibet to Southeast Asia all the way down to Indonesia and the Phillipines. Sometimes “Asian” even includes Middle Easterners. There must be pelvic variation among all the Asian ethnicities.

Say you are correct though, and it’s a pelvis issue. There could just as well have been homo sapiens males mating with neanderthal females.

What matters here is weight/head size at birth. That Californian study was taken from case histories over the period 2000 to 2005. Do you really think nutrition has improved that much for Asians living in California in the past 7 years? I would be surprised if it had changed at all during that period. Post 2008 I guess it’s possible it even got worse.

The study reported that Asian babies had lower median birthweights than European babies. It also reported a much higher rate of Caesarian deliveries for Asian mothers with European husbands than for European mothers with either European or East Asian fathers. They attribute this to possibly smaller pelvis size in Asian than in European women.

White mother/Asian father had the lowest rate of Caesarian births of 23%, compared to 33.2% for white father/Asian mother. If that’s not an issue of the head size versus the pelvis/birth canal size, which is it caused by?

http://www.healthnewstrack.com/health-news-705.html

Have you ever watched a baby being born up close? It’s a tight fit and a very painful process, and the baby’s head has to change shape to get through the birth canal. It doesn’t take much of a size difference to create a major difficulty.

Assuming Neanderthal babies had bigger heads than AMH babies, which seems like a reasonable assumption, then the birth could be really difficult, and there were no surgeons around to perform Caesarian sections back then, so far as I know . It doesn’t necessarily mean it was always impossible – there’s a natural variation in head size in babies. But it could suggest that successful Nanderthal/amh births were not that common. The child would then need to grow up among amhs, becuase the alternative was extinction.

This all suggests that successful hybrids who went on to breed themselves successfully with amhs were a rarity.

Case closed, I’d say.

I found a study showing that smaller women in general have more c-sections: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0020497

I’d just like to see more data specific to this circumstance, and that takes into account real measurements of pelvis, height of partners, etc. The hard evidence seems lacking.

Would you like to put some money on that?

If they took those tests for birthing difficulties again in say, 5-10 years, would the difficulties still exist? I doubt it. I don’t think a half-white, half-Asian baby is so much bigger than a 100% Asian baby such that it would account for difficulty with birth for an Asian woman.

Do you have links to any research? I saw something from 2008 about a California study but did not find much info on the subject.

It’s not a reason for them to not do it, you understand. Birthing difficulties happen – it’s our (human) fault for developing big brains.

Separately, I mentioned that there was no evidence at the time that hybrids would be fertile. Even now, it looks possible that they might have been fertile only rarely. Or not – we have no real idea how often interbreeding events might have taken place.

I take Greg’s point about mammalian hybridisation, but birth difficulties in humans are not that rare, and both AMHs and Neanderthals are/were human.

I said nothing about grossness – this is not a sexual act with an animal of another genus that we’re talking about. The reference to sex with sheep is totally irrelevant in my view. We’re talking about sex between two humans, there’s no call to invoke bestiality.