Squamates as prey: Predator diversity patterns and predator-prey size relationships

Abstract

Understanding the relationships between prey and their predators can provide important insights into evolution of defenses, foraging ecology, and functional roles within their ecosystem. Squamates (lizards and snakes) exhibit a wide range of morphological, ecological and behavioral variation and are model organisms for the study of the evolution of anti-predator traits, making them an ideal group to search for general patterns in predator-prey relationships. We compiled a squamate predator database that consisted of 1152 squamate predation-prey interactions representing 396 lizard species from 30 families and 217 snake species from 13 families. We quantified the predator taxonomic diversity and explored the relationship between predator size and prey size. Both lizards and snakes were preyed upon by a greater diversity of squamate predators compared to avian and mammalian predators. Snakes appear to be more vulnerable to a broader size range of predators compared to lizards, which is likely attributed to differences in their body morphology. These results provide further support for the hypotheses that predation pressure may affect the evolutionary trajectory of squamate defenses.