Ah, see but it also says "substantial genetic differences between different current human populations"

Which means different areas have genetic differences. But the human population as a whole isn't changing. Maybe we might split off in to different species. But I think there is too many people for this to happen. People moving about all the time etc.

Or maybe "There's also various types of meiotic drive to take into account where a gene manipulates meiosis in such a manner as to ensure that it's passed on to a disproportionate amount of the offspring of its hosts." This would change that. Not sure though.