Chewing Off Your Own Penis
Banana slugs sometimes chew off their partner's penis after mating — or their own if it gets stuck. The penis doesn't grow back.
Banana slug sex is not for the faint of heart. These bright yellow gastropods have a mating ritual that can end in apophallation — the chewing off of the penis.
Here's how it works:
Banana slugs are hermaphrodites, meaning each individual has both male and female organs. During mating, they exchange sperm simultaneously. Their penises are impressively large — sometimes as long as the slug's entire body (6-8 inches).
The problem? Sometimes the penis gets stuck after mating. When this happens, one slug will gnaw off the stuck penis — sometimes their partner's, sometimes their own.
The severed penis does not regenerate. A slug that loses its penis can still reproduce, but only as a female from then on.
Scientists aren't entirely sure why this happens. Theories include: - The penis simply gets stuck in the partner's reproductive tract - The biting slug is removing a competitor's ability to mate as a male - It may help the remaining sperm stay inside the recipient
Despite how brutal this sounds, banana slugs are important decomposers in Pacific Northwest forests, breaking down dead plant material and recycling nutrients.