Recently I learned about Human Acceleration Regions (HARs), parts of our DNA that remained almost unchanged in our mammalian ancestors, and then diverged very rapidly in humans between 500-200kya. And it made me wonder, is this why the ancient Hebrews said humans alone are created in the "image and likeness of God"? At any rate, it establishes that we are a very different kind of animal, even from our closest relatives the chimpanzees.
Anthropologists make a similar point from a different perspective: at some point roughly within that time span, human biology and culture began to co-evolve, so cultural practices would bring about physiological changes, which would in turn unlock new practices, and so on.