In its youth, the peacock has a magnificent tail that it uses to attract mates. The peahens pretend to be impressed and this ensures the survival of the species. Later, when the peacock reaches middle age, it looks in the mirror and wonders just what the hell happened.
The male seahorse carries the baby seahorses, as many as two thousand at a time, in a specially evolved pouch. The male seahorse claims he is perfectly confident of his sexuality and sees nothing wrong with carrying a man purse. During the gestation period the male loses track of all its old college buddies and begins talking about Montessori schools and minivans. Within twenty-five days, the young emerge and begin asking for money.
The male salmon swims miles upstream against rapids and waterfalls to the same spot where it was born. There, the lucky survivors spawn, and within a few days, all their scales fall out, and they die. They try to tell their young, disturbingly called "fry," what's in store for them, but does anybody ever listen? No.
The female praying mantis attracts the male by a specially seductive wiggle of her lower abdomen. A few days later, the female tells him she's pregnant and gives birth to 20,000 babies. The male has a DNA test performed, and it turns out that all but 5,000 are his. The female sues for child support and files a restraining order. Then she eats him.
Each year hundreds of thousands of young monarch butterflies migrate from as far north as Canada to Cancun, Mexico, where they gather in thick lumps and the females display their wings for "Butterflies Gone Wild" videos. Their fathers stay behind and complain that in their day they were perfectly content to go to Fort Walton Beach, and these young ones don't appreciate how good they have it.
The male wood duck builds an elaborately domed nest of twisted twigs and leaves. After all the desirable mates have gone to better-looking ducks, it settles for what it can get and begins to raise a family. The male stays home and tends the eggs while the female is out with her girlfriends. During this time, the male practices quacking things like, "Wipe your feet before you come in the nest! Do you think twigs grow on trees?" and "What, were you raised in a pond?"