In case it needs to be explicit: the men in the story are worried that their women may become with another man's child, whereas the women are worried that the man will not remain loyal and help raise their child.
When both of those are in effect, does jealousy dissipate?
> The carrying out of a paternity test outside the legal framework carries penalties ranging from one year's imprisonment to €15,000 fine.
Official source: https://www.service-public.fr/particuliers/vosdroits/F14042?...
But in practice, I expect a paternity test to come in an otherwise troubled relationship, so I don't know how often it happens that both parents would seek to get one.
What’s the gene pool loss if the kid actually isn’t his? Seems to me that that his dating pool will then expand from zero to many. A rational male may think that offering more than 18 years of his life is more significant than not offending someone once.
It's like drawing conclusions about human society based on just watching prison inmates interact.
- Fathers (depending on species) can't be confident a given child is theirs. Mothers can be confident due to giving live birth. Fathers have a lower incentive to care for a given child, since expending effort on offspring that's not yours is evolutionary detrimental; everything has an opportunity cost.
- Mothers have a much higher investment in the child from the moment of conception: Due to the extra food they must consume to nourish the embryo, the effects of pregnancy etc. By comparison, sperm is cheap. Neither parent wants to let the child die due to lack of care, but the fathers are in a better position to call the mothers' bluff than vice versa due to the sunk cost.