Maybe someday science will be able to tell us if this has anything to do with the differences in social developments...farming...cities...armies etc.
All these things began to emerge as Neanderthal was disappearing.
bttt
we are neanderthals.
However, to be PC the writers didn't say any blacks at all had any Neanderthal genes ~ but you are clever to have noticed the difference. Remember, if the writer had said "blacks have Neanderthal genes" the NAACP and their running dog lackeys would be bouncing off the walls screaming "He used the N-word".