Meeting Abstract
Many organisms possess antipredator traits that confuse, decoy, or startle predators to decrease mortality from predation. Paradoxically, some of these antipredator traits are present only in juveniles, with antipredation traits lost during ontogeny. While potential drivers of ontogenetic loss of antipredation traits can include shifts in predators, prey, or intraspecific competition, the specific factors that drive the loss of antipredation traits with ontogeny are not well known. We studied the ontogenetic loss of the bright-blue tail of skinks, which diverts predatory strikes away from vital body parts towards the tail. We used 1) a survey of morphology and body size of three skink species, 2) a clay model study of predation rates, and 3) a study of body and tail energetics to determine the factors that drive ontogenetic loss of the blue tail. We found that the blue tail is lost at the same size among three different species of skinks, which implies similar selective forces drive the loss of the blue tail among these species. We also found strong support that the ontogenetic shift in coloration is related to differences in predation pressure with increased size, and not differences in energetics of tail loss. Our findings illustrate how predation can drive complex expression of antipredation traits, which has implications for understanding the evolution of phenotypic diversity.
