Highly Endangered Limpet Changes Sex to Improve Survival in the Wild

Animals will adapt and change in order to survive. Nowhere is this more apparent than with the endangered limpet, a sea snail that's one of the rarest invertebrates in the Mediterranean Sea. Now, scientists have discovered that these snails can change their sex from male to female and vice versa, improving their chances of survival in their environment.

The ribbed Mediterranean limpet, Patella ferruginea, is in danger of going extinct and is classified under the maximum protection category in the Spanish Catalogue of Endangered Species along with other animals, such as the Iberian Lynx. Yet this snail is difficult to conserve because so little is known about its biology. That's why scientists decided to investigate a bit further.

"One of the problems involved in the recovery of the Patella ferruginea is the lack of knowledge regarding basic aspects of its biology," said Javier Guallart, one of the researchers, in a news release. "This is the first time we have encountered this part of its reproductive strategy on an experimental basis."

Until now, the ribbed limpet was thought to be a protandric hermaphrodite species. This means that when young limpets reach sexual maturity, they do so as males. Then, at some point during their vital cycle, they change sex and become females. This strategy is often employed by molluscs, but it turns out that it's not the one that ribbed limpets use.

Scientists discovered a number of specimens previously sexed as male that were now female. This wasn't the surprising part, though. The real shock was discovering a female that had become a male between consecutive reproductive periods.

"The results obtained were fascinating," said Guillart in a news release. "This reverse sex change from female to male was something anecdotally described for a species of limpet. During subsequent periods, between 2010 and 2011, we discovered that this was not an isolated case; a whole new approach to the method of reproduction of this protected species, which helps it to survive."

The findings reveal a little bit more about this rare species. More specifically, understanding the limpet's biology is crucial for arming conservationists and employing policies that will help protect this species. Currently, there's still a long way to go when it comes to the limpet's recovery, yet it's possible that with this unusual reproductive strategy, the limpet may very well succeed.

The findings are published in the journal Invertebrate Reproduction & Development.