/sci/ - Science & Math

>>12666821
I have my doubts towards the OoA theory but the information in that picture is presented all fumbled up. The only thing this says is that pure Africans don't have Denisovan or Neanderthal DNA which is something we've known for a while, it doesn't raise objections or cause controversy.

A dog and an ape are separate species because they fill different roles ecologically, can't produce fertile offspring, and are genetically dissimilar.

But some species can produce fertile offspring, and create a hybrid.
>60 ka Homo sapiens who leave Africa in this wave may have interbred with the Neanderthals they encounter

Most non black people have some Neanderthal DNA. And Neanderthals were a separate species. Why?
If ancient homo sapiens could fuck neanderthals, why would they be considered different species?
If non black people are neanderthal hybrids, why aren't they classified as separate from people who didn't interbreed with neanderthal? And why aren't Denisovan hybrids separate?

If we could breed with them just fine, why wouldn't they just be classified as different ethnicity's?
Modern Homo Sapiens ethnicity's fill a niche, why aren't they all classified as different species?

http://news.nationalgeographic.com/news/2014/07/140702-genetics-tibetan-denisovan-altitude-science/
according to this, Tibetans are better adapted to their climate through genes picked up in denisovan. That makes them genetically different than say, a black person living at a very low elevation. And they fill a niche.
Why are they still the same species? Interbreeding apparently isn't necessarily strict in defining a species.

To bring it to a less-racist sounding place, why are all dog breeds, Canis familiaris? Most fill a different role, are genetically dissimilar, and some can breed but others can't. Why isn't a little froo froo dog a different species than a great dane?

Assuming humans keep evolving through genetic drift or whatever, how long until an Inuit and an Aborigine are different enough to be considered separate?

If we start fucking with our genome, how different until that's considered a new species?