(Phys.org)—A trio of researchers with Anglia Ruskin University in the U.K. and the Australian National University has found that the male fiddler crab uses its oversized claw to get the attention of a prospective mate and then uses drumming to demonstrate its degree of physical fitness. In their paper published in the journal Royal Society Open Science, Sophie Mowles, Michael Jennions and Patricia Backwell describe their study of the crab and what they found.