Male fiddler crabs produce female-luring vibrations in their burrows

The vibrations and pulses that male fiddler crabs produce when they are trying to lure females into their burrows to mate are surprisingly informative. These signals serve as a type of "Morse code" that the females decipher to learn more about the size and stamina of their suitors. This is according to a study by Japanese researchers Fumio Takeshita of Nagasaki University and Minoru Murai of the University of the Ryukyu, published in Springer's journal The Science of Nature.