Adaptive introgression:
[The researchers] went looking for instances of adaptive introgression — a phenomenon in which a newly introduced piece of genetic material is so beneficial that it quickly radiates out into the entire population. [“Your Neanderthal DNA might actually be doing you some good,” Sarah Kaplan, WaPo]
Reading that last phrase, I was struck by the notion that “population” must implicitly have the modifier “future” on it, since genes, for creatures such as us, is not a directly transferring piece of genetic material.
But it is for bacteria.
“Quickly,” for us, would imply at least a few generations, which would be inversely related to the level of promiscuity practiced by the population.
