For this to be seriously interesting we would need information on the extent
to which humans cooperated prior to the 'invention' of language. Also, Ian
Tattersal, in Monkey in the Mirror, tells of a troop of monkeys who did
learn from each other. (I forget the precise species.) They lived along the
shore and their main food supply was found there; it was often sandy. Then
some young monkeys began to wash their food in the surf, and before long the
adult females were doing so. (I forget whether the adult males ever
learned.) Eventually, the whole troop washed their food.
Anaother anecdote I can't confirm because I forget my source & without a
source mere memory is undependable. But here is the story as I remember it.
Baboons are among the most hierarchial of all primates, with rigid lines and
complete control by the Alpha males. One troopo of baboons regularly got
food from a nearby village dump. Then some rotten meat was cast out, and
naturally only the alpha males got to eat it - and they all died, leaving
only females and young baboons, and they developed a wholly cooperative
culture. The young males grew into the culture. And what is more, males
separated from their troops that joined this troop adopted its culture. I
don't remember how many generations the new culture lasted.