Is it culture or genes or both that drive some groups to have high completed family sizes?
It's both. There is a sustainability factor within nature for a large or small family. The idea is that parents that do not nurture infants, like ants will produce more than parents who spend the energy to nurture their infants, like humans. This is usually controlled through evolution depending on resource usage, space, etc. There is usually a limit for every species
However, for humans, with the rise of agri-technology (i just made that up btw, don't know the term), you can say that the limit has increased.
as much as I like agri-technology I think the term is farming or if you want to be fancy agriculture.
Well see i would have said farming, but im referring to the technologies that have made farming efficient; hence agri-technology
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