This is an argument I've heard previously but in the context of jealousy. The idea then is that men are on average more "sexually" jealous (don't want their heterosexual partner to have physical intimacy with other men) whereas women would on average be more "socially" jealous (don't want their heterosexual partner to have emotional intimacy with other women.)

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.