“Both groups would seem to us dirty and smelly...”
—Oh?
“Humans today still should have some Neanderthal genes.”
—But we don’t.
“...the unanswered question of why Neanderthals died out is even more puzzling...”
—Possibly mating with Cro-Magnons did not produce viable offspring.
Red hair is a Neanderthal gene.
Know any redheads?
Not cro-magnum, homo sapiens sapiens.