Fiddler crabs are found along sandy beaches, and their life spans are less than two years. Female crabs have two small claws, and males have one claw larger than the other claw. Males use their smaller claw for feeding. The larger claw is waved up and down to attract females and attack other crabs. Female crabs choose their mates based on the size of the larger claw and waving action. Which is one reason why females select males with large claws?