Fiddler Crabs Have Sex with Neighbors, says Study

"Love thy neighbor" has a whole new meaning.

Sometimes sex is the best weapon for defense. At least that's what some Fiddler Crabs use to survive. According to new research, female crabs are protected by nearby male crabs in exchange for sex.

In a new study published in the journal Biology Letters, researchers at the Australian National University in Canberrafound that female Fiddler Crabs will have sex with neighboring males in order for protection.

Michale Jennions, a scientist who helped conduct the study, was surprised at the partnership between the two sexes. "The fact that the neighbor comes over and helps to defend another territorial individual is pretty unusual," he said.

Jennions and his colleagues were interested in how the female Fiddler Crab defends herself, since she lacks the giant claws that males use to fight off intruders. What they found was that the lady crabs, while normally very picky about their partners, chose to have sex in echange for protection.

"This study shows, for the first time, that in exchange for sex and other benefits, males protect their female neighbors from territory-seeking male intruders. The paper provides the first evidence of 'defense coalitions' between territorial males and females," said Jennions.