Abstract

Male body size was tested for its influence on female choice and male-male competition among fiddler crabs, Uca paradussumieri Bott, 1973. Both processes, that drive the evolution and maintenance of male traits and female preferences, had an influence on male body size. Females preferred larger males as mates. Copulation time was shorter in cases where females were larger than males. Compared with rejected males, accepted males had greater carapace breadth and length. Larger males were more successful in competition against smaller males, but body size had no effect on fighting duration.