Sea Slug Owns a Disposable Penis

Japanese scientists are surprised at the bizarre mating behavior of a sea slug. They are amused to see how a sea slug is able to detach its penis after copulation. Not only this, it can even re-grow and re-use its penis.

Mainly found in the Pacific Ocean, Chromodoris reticulate is a red and white slug and is a soft-bodied marine mollusk.

The sea slug, which disposes its penis after sex, doesn't have to worry about its genitalia, as it needs just 24 hours to regenerate its male organs and mate again.

Equal to the size of a human thumb, the slug is a simultaneous hermaphrodite. This indicates its capability to perform the role of a male by donating sperms and also the role of a female, by receiving sperms from the partner during copulation.

According to the lead author Dr. Ayami Sekizawa, nearly one-third of the internal penis length is disposed after copulation. After this, it is able to re-grow the penis gradually to its original length.

Bernard Picton, curator of marine invertebrates at the National Museums Northern Ireland, was quoted in BBC stating, "The general apparatus is on the right hand side of the body. So two nudibranchs come together and one faces one way and one faces the other way, with the right hand side of their bodies touching."

What is actually happening is they are both donating sperm to the other one.

The study was conducted on sea slugs collected from the shallow coral reefs of Japan. They noticed that they mated 31 times, reports BBC. The animals were able to mate three times in a row, with gaps of 24 hours in between.

This sort of mating behavior is very rare in the animal kingdom.

The study was published in the Royal Society's journal Biology Letters.