A male <em>Solenosteira macrospira</em>, left, carries snail eggs on its shell. But not all of the eggs were fertilized by him. Females, like the one on the right, deposit the eggs into papery capsules and attach them to the males' shells.
A man is not a mollusk, and many men probably think that's a good thing. And it's not just because a mollusk is a squishy invertebrate with a shell. It's also because for at least one species of mollusk, the males do all the heavy lifting when it comes to childcare.
The species of mollusk we're talking about is Solenosteira macrospira, a marine snail about 2 inches long. These snails live off the coast of Baja California, and during the mating season, the beach is awash with male and female snails in connubial bliss.