At a minimum, how many people would be able to get a society going, presuming rough equality in numbers between the sexes? It could be fragile for awhile, and probably first cousin consanguinity would have to be tolerated until the population hit higher levels. I've read a little about population bottlenecks and migration, but still haven't got a good idea about the numbers that would be necessary to get a few generations going and on their feet. Forty? Four hundred?
Does anyone have a good source on this?