The lesser mole rat not only digs an entire subterranean house for itself, complete with storerooms, halls, bedrooms, and a “wedding chamber” where all mating takes place, but actually constructs a separate bathroom which, when filled, is sealed off from the rest of the house.

Sea worms mate in the following way: at mating time, males and females swarm together. Suddenly the females turn on the males and bite their tails off. The tails contain the males’ testes and sperm. When they are swallowed and acted upon by the females’ digestive juices, they fertilize her eggs.

The female praying mantis devours the male while they are mating. The male sometimes continues copulating even after the female has bitten his head and part of his upper torso!