How sure are we really about that?
There is an large amount of history backwards in time, and not a large amount of reliable documentation regarding the amount of partners people had.
There is an large amount of history backwards in time, and not a large amount of reliable documentation regarding the amount of partners people had.
And I'm relatively sure that in smaller communities there's less chance of anonymous sex: the social control, lower frequency of encounters.
Imagine the opposite: 1000 years ago, AIDS and gonorrhea spreading all over the world at current rates (88 million cases of gonorrhea per year) without any medication or protection. That would have ravaged the population, or made us immune, but neither happened.