[extropy-chat] Human Evolution

[kevinfreels at hotmail.com]

Is anyone here a primatologist, anthropologist, or geneticist?
I am working on a research paper for no particular reason than to organize my thoughts and I need to find out a few things.
1.) Bonobos show that they diverged from chimpanzees about 2 mya. Are they capable of breeding with regular chimpanzees. Do they show any history of doing so? If so, do they produce sterile offspring?
2.) A donkey and a horse may make a mule. Sterile, but a creature that has characteristics of both horses and donkeys. A bengal cat is a cross between the asian leopard cat (felis bengalensis) and a domestic house cat. The male offspring are also sterile, but the females may breed yet again with a domestic housecat male and produce males that are not sterile. Are there similar occurrances in the primate world?
3.) Is there a single known primate that a human is capable of breeding with, even if it were to produce something really weird looking and sterile? What about crosses between Gibbons, baboons, orang-utans, gorrillas, etc?

My research didn;t originally go in this direction, but it seems to be making a slight turn towards problems with the entire classification system. The entire Homo fossil record is full of weird combinations of archaic and modern type hominids. Combinations such as human-like teeth and small brains, large craniums with supraorbital ridges, bipedal stature with small brains, etc. 

I am starting to get the idea that the last 3 million years was a huge orgy of crossbreeding and that the fossil record, given the chance process of fossilization, will probably never be able to tell the whole story. Maybe a group of modern humans about 200k years ago simply decided to stop crossbreeding. H. sapiens may have assimilated H.neanderthanelsis as they moved into Europe and Asia, but weren't able to produce viable offspring either because neanderthal women weren't capable of giving birth to the human babies (probably due to a longer gestation period) and/or the production of sterile offspring. 
Bipedalism may have fluctuated back and forth, (3 steps forward, two steps back) in several lines until the right conditions came along that simply required it. 
The Oldowan tools show up about 2.4 mya. This is towards the end of the A. africanus period. Might older tools and younger fossils of A africanus be found? Are someof the fossils discovered simply crossbreeds of different species?

Comments?





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