A male fiddler crab (Uca lactea) FUMIO TAKESHITA
Male fiddler crabs use a number of methods to attract a mate, including waving their claws to draw females to the entrances of their burrows, and emitting vibrations to invite them in. But females are discerning, according to a recent study from researchers in Japan: they preferentially visit males that produce vibrations at a rate correlating with larger size. The findings were published last month (May 30) in The Science of Nature.
“Females significantly preferred males with higher pulse repetition rates when they were positioned at the entrance of the burrow,” the authors wrote in their paper, “indicating that the females use male vibrational signals to decide whether to enter the burrow.”
In manipulative experiments, the team used a “dummy female,” controlled by a length ...