''So, apart from not being rational profit maximising capitalistic individuals, early human tribes had not even heard about the gospel of the modern nuclear family.''
I think you are going too far with your capitalism thesis. Certainly far farther than anything I said, or suggested. I feel like whatever I may say it'll be turned into a political/economic issue about capitalism. Tribal society utilized the resources they had available and traded/exchanged for whatever they could not, given their location or whatever reason, produce for themselves, flint, shells, foods, etc. It is what it is.
