Two hours.
From the tribe of 1k-10k modern humans who killed off all the other human species 70,000 years ago, to the Yamnaya steppe nomads 5,000 who killed off 90+% of (then) Europeans and also destroyed the Indus Valley Civilization.
So much of what we thought we knew about human history is turning out to be wrong, from the ‘Out of Africa’ theory to the evolution of language, and this is all thanks to the research from David Reich’s lab.