There are four human speciation events: From the formation in the south african

There are four human speciation events:
From the formation in the south african marshes, and in order:
– E african rift valley is certain.
– Dry Persian Gulf almost certain
– Tibetan Plateu, looks likely
– Somewhere in europe. (three ice age groups in southern europe, and whatever happend to the ancient north eurasians in upper russia.)
At the end of the ice age these four groups were as different as europans and east asians.
Technically those are four species (races).

Out of africa is certain but so is back and forth migration in and out of it – especially along the coastal route from africa to india to east asia and the islands. Think of mixing fluids of different densities in stead of mechanical systems when you think about migration and hybridization.

Human adaptivity and reproductive placticity makes possible extensive hybridization.
All hybrids express the compromiae (median) of the traits of each race (species).
The most important of all is domestication syndrome and intelligence, both of which are caused by neotenic evolution (domestication) in favor of trading aggression and impulse for cooperation and cognitive agency (thinking).

Cheers.

Reply addressees: @hbd_orbiter @SwannMarcus89