On the Incidences of Cannibalism in the Lizard Genus Sceloporus: Updates, Hypotheses, and the First Case of Siblicide

Although cannibalism is not unusual in amphibians, it is rare in reptiles. The working hypotheses on the occurrence of cannibalism in reptiles assume that it occurs as an opportunistic feeding event, but these hypotheses have not been formally described. Here we report a cannibalistic event in the Eastern Fence Lizard, Sceloporus undulatus undulatus. DNA tests were used to confirm that the lizard was consumed by a sibling, and thus our report is of the first case of siblicide in the genus Sceloporus. We also present an updated list of cannibalistic events, as reported in the literature, for the genus Sceloporus, and describe testable hypotheses regarding the rare occurrence of cannibalism based on juvenile and adult densities, food availability, and distance to nesting grounds.