Meeting Abstract
Conspicuous antipredator coloration has long fascinated biologists and provides some of the most striking examples of convergent evolution. Research has tended to focus on mimicry and aposematic coloration, which have evolved convergently in many groups and is governed by spatial and temporal heterogeneity of selection. However, decoy coloration is another type of antipredator coloration that directs predator attacks towards a brightly colored but non-lethal body segment, which may exhibit different macroevolutionary dynamics. We studied the evolution of the brightly colored (red, green, blue, or yellow) tail of many lizard species, which effectively directs predator attacks towards the autotomous tail and away from vital body parts. Using a time-calibrated phylogeny of nearly 700 species, we studied the evolutionary dynamics of decoy coloration among lizards in the clade Scincoidea. We estimated the number of origins of the blue and red tail, tested the evolutionary association of the blue tail with dorsal striping, and characterized how temporal dynamics vary among tail color type using phylogenetic comparative methods. We found that both the red and blue tail have similar numbers of evolutionary origins, and reversions to the cryptic tail color are rare. In addition, the presence of either the blue or red tail was evolutionarily correlated with dorsal striping. Finally, we found that the blue tail had both old and more recent origins, while the red tail had multiple recent origins. These results suggest that the evolution of decoy coloration can be dependent on the evolution of other phenotypic traits (dorsal striping) and highlights the dynamic and convergent evolution of decoy coloration in lizards.
