Look. Neanderthals and Denisovans split,
and they both appeared to have interbred
with others and even each other -- after
they became separate & distinct populations.

Both interbred with moderns.

But there's also "Mystery Meat" ancestors
out there, somewhere, which are known from
the DNA studies...

Okay, so what do you know? Simple: That
populations spring up, spread out, split, interbreed
(maybe a lot of that spreading is due to
interbreeding) and then the whole process starts
all over again. That's the model we have, we know
as fact, so why wouldn't that same model be
working 2 million years ago? Why not even further
back?

Does savanna nonsense allow any of this to happen?

Of course not. But we know it happened anyway.

Does Aquatic Ape allow for this?

YES! It would be a prediction of Aquatic Ape, really.
They spread out, occasionally some groups pushed
inland and adapted, creating distinct groups, and
those distinct groups met others or, now get this,
the Aquatic population connected them to all the
other groups. Have sex with the Aquatics and they
move down the line, consuming resources on a
stretch of beach then finding a new stretch to
exploit, they encountered different inland groups
and shared their DNA... picked up the new DNA
that the inland groups acquired...

Yup. Aquatic Ape provides for what we know
happened, savanna idiocy can't.

-- --

https://jtem.tumblr.com/post/696108919478796288/