Study finds that male fiddler crabs are a**holes.

Photo: flickr/Bernard DUPONTThe males of many animal species will "coerce" females into mating by force. But according to this study, male fiddler crabs take it a step further. They lure females into their burrows, allow the ladies to enter first...and then block their escape. As the researchers in this study (delicately) put it, "upon entry 79% females that enter will become trapped and almost all of these females (90%) produce a clutch of eggs. Our observations suggest that males are able to gain fertilisations from females that may not have remained in the burrow by trapping them and coercing them to mate." Are male fiddler crabs the Ramsay Boltons of the animal world, or is there a more despicable animal rapist out there? Tell us in the comments below!Ladies First: Coerced Mating in a Fiddler Crab "In some species males increase their reproductive success by forcing females to copulate with them, usually by grasping the female or pinning her to the ground to prevent her from escaping. Here we report an example of males coercing copulation by trapping a female in a confined space. During mate-searching, female Uca mjoebergi fiddler crabs visit males and choose whether or not to enter their burrow for inspection. Males typically enter the burrow first and we found that 71% of females will follow him down and 54% decide to stay and mate. However, some males use an alternative tactic where he will wait for the female to enter the burrow first, after which he traps her inside. Although a significantly lower percentage of females will enter a burrow following this behaviour (41%), upon entry 79% females that enter will become trapped and almost all of these females (90%) produce a clutch of eggs. Our observations suggest that males are able to gain fertilisations from females that may not have remained in the burrow by trapping them and coercing them to mate." Related content: Spider sex is kinkier than you thought!What makes a sexy wasp sexy? Funny you should ask…Spiders perform female genital mutilation to ensure faithfulness.