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.

When leeches mate, the leech playing the male role (leeches are hermaphrodites and can assume either sex) clings to the body of the female and deposits a sac of sperm on her skin. This sac produces a strong, flesh-deteriorating enzyme that eats a hole through the female’s skin and fertilizes the eggs within her body.

The females in the pride tend to do the majority of the hunting. They work as a group and use intelligent hunting tactics to catch prey which they would not be able to catch alone as they are faster than them.