Cannibalism in the Andean lizard Liolaemus orientalis

Abstract

ABSTRACTCannibalism is a recurrent behavior across the animal kingdom, with important ecological and evolutionary consequences due to its potential trade-offs on the fitness of involved individuals and demography dynamics. Cannibalism has been reported in eight species of several phylogenetic lineages within Liolaemus, a highly diverse genus of Neotropical lizards. Within the Liolaemus montanus series, two species are reported to eat juveniles in captivity. We observed a female Liolaemus orientalis, another L. montanus series member, which had ingested a juvenile of its own species in the wild. As it generally happens with other lizards, cannibalism in Liolaemus has been suggested to be performed by the larger sex, with L. chiliensis being the only other case observed until now in which the cannibalistic individual was a female. The fact that females are slightly smaller than males in L. orientalis means that our observation is an exception to previously observed trends. We suggest that there is a relationship between this behavior and the presence of a masculine trait in the cannibalistic female: developed precloacal pores. We also discuss how refuge availability may influence demography and the probability of dispersing juveniles encountering adults, increasing the chances for cannibalism to play some role in population density regulation.