Upvote:-2
Well we can do one better than a Jared Diamond answer with a Dave Graeber answer: complex class societies where methods for accounting for what property was and for accounting of the forcing of property from people developed differently in different periods. This is because some societies succeeded in destroying nascent ruling classes, or resisting foreign imperialism, more successfully than others. In contrast to successful human societies which forced property to not come into being, failed human societies developed accounting, and thus writing, and thus man's enslavement of humanity. The division line is complex, but has to do with the capacity to concentrate violence, which largely means terrain and access to population bomb techniques of food production.
Upvote:-1
I disagree with the comment by T.E.D. that it is a "Guns, Germs and Steel" question. Jared Diamond gives an answer for colonizing civilizations in competition, but I don't think it applies to earlier periods. My answer is that it is at least in significant part random chance.
The lower paleolithic is was roughly 2,000,000 to 200,000 years ago.
The middle paleolithic was roughly 200,000 to 20,000 years ago.
The upper paleolithic was roughly 50,000 to 10,000 years ago.
The neolithic was roughly 10,000 to 5,000 years ago.
Those numbers are not exact, there is some overlap, and one could quibble about the exact dates. But one thing stands out. The earlier periods were much longer.
A difference in just one percent in the duration of the lower paleolithic would be more than everything since the neolithic age. If different societies had evolved in isolation, one would expect some sort of normal distribution of the end dates -- some sooner, most in the middle, some later. Of course they were not isolated, so more-developed societies contacted less-developed societies, and in a very few cases less-developed societies contacted more-developed ones.