[sxakin] Why hunter-gatherers went out with unrelated individuals, even though they often preferred their own descendants and close relatives to build their camps, is a mystery. M. Dyble and his team found at least a well-founded explanation for that apparent paradox7.
He ran 100 simulations of two “agent-based models” (see the Wikipedia for an explanation) of a selection process for group members. In the first one a gender-egalitarian situation is assumed, both partners of a couple determine the selection of the group members, in the other model, a non-egalitarian situation is assumed, selection is a privilege of the males of the families. Below is a presentation of the results of those computational models8.
He tested these models against genealogical data of two groups of gender-egalitarian hunter-gatherers and of a group of Brazilian Paranan farmers. They corresponded to what the computational models had predicted.
The Agta belong to a group of hunter-gathers in Congo, the Mbendjele belong to a group of hunter-gathers in the Philippines. The composition of both showed that 50% of the couples were distant affines or not related. 16.7% of them were the non relatives. The percentage of non-relatives for the farmer group was only 4.2%. The conclusion can not be clearer, depending on how the selection is made, gender-egalitarian or non-egalitarian poeple lived together with a significant number of non-relatives or with only a minimal number of non-relatives9. In the latter case, we have the model of the patriarchal society, typical of agricultural society.
7M. Dyble et al., Sex equality can explain the unique social structure of hunter-gatherer bands, 2015.
8Idem, p. 1
9Idem, p. 2
10Shane Lunny, Early men and women were equal, say scientists, 2015, Medium, retrieved at https://medium.com/@shanelunny/early-men-and-women-were-equal-say-scientists-eabbd380d05c on 10/10/2019