The effect of size and cheliped autotomies on sexual competition between males of the mud crab Cyrtograpsus angulatus Dana

DALEO, P; T. LUPPI; A, MENDEZ CASARIEGO; M. ESCAPA; P. RIBEIRO; SILVA, P; O, IRIBARNE

MARINE BIOLOGY

Elsevier

Lugar: New York; Año: 2009 p. 269 - 275

0025-3162

Abstract Size advantage in male–male competition over mates, combined with male preference over large females, is a common feature that can drive to size assortative mating and, eventually, sexual selection. In crabs, appendage autotomy can aVect assortative mating and opportunity for sexual selection by aVecting size advantage in mating contests. In this work, we evaluate the eVect of size and appendage autotomy in generating assortative mating in the mud crab Cyrtograpsus angulatus. Field observations of guarding pairs in two diVerent populations show a positive correlation between carapace width of males and females in both the populations. In one of the populations, incidence of appendage autotomy was low and the variability in the size of reproductive males was lower than the variability in the size of randomly collected males (i.e. only larger males were successful in getting a female), whereas there was no diVerences in the other population (i.e. most male sizes were successful) where the incidence of appendage autotomy was very high, indicating that the importance of size is higher when the incidence of autotomy is low.