"You’ve spread your seed, so to speak, and joined the ranks of your own father... not only are you a dork when you lapse into goo-goo talk, but now you’re less of a man scientifically."
Oh, man, the guys will have their revenge for all the cat litter box cleaning they had to do when we women were pregnant and had to be protected from toxoplasmosis.
During pregnancy, the man is the pussy man, dealing with the cat poo. But now that the baby is born, if she doesn't want a pussy man, depleted in testosterone, it is her turn to handle the poo.
Now, these arguments about division of household labor have a new dimension: My dear, are you anti-science or are you trying to emasculate me?
ADDED: Is it manly to make that argument? It suggests you need to conserve the testosterone you have. It would be more macho to act like you have plenty to spare. Also, I think diaper changing is one of the more manly baby-related chores? It's a dirty job and someone's got to do it. We don't have a study about which specific baby-relted activities are testosterone depleting. I'm going to speculate that it would tend to be the ones like bottle/breast-feeding where you look for a long time into the baby's eyes... not the one where you're looking at the nether regions.