Comparative gliding performance of Anolis lizards among three Caribbean ecomorphs.

Anole lizards (genus Anolis) have repeatedly and independently occupied arboreal niches, and in parallel have evolved associated morphologies and locomotor behaviors. In arboreal vertebrates more generally, parachuting and gliding have frequently evolved in response to selective pressure for targeting and controlled landings during either falls or intentional jumps. Here we describe morphological features and aerial performance among five anole species representing the trunk-ground, trunk-crown, and crown giant ecomorphs. Aerial behavior within a vertical wind tunnel was used to evaluate gliding performance, including body orientation, velocity, and glide angle. All study species exhibited controlled non-equilibrium aerial descent. When accounting for phylogenetic relatedness among species, heavier species exhibited greater downward velocities and glide angles. Interspecifically, glide angles were also inversely correlated with wing loading. By contrast, gliding performance did not differ significantly among the three Anolis ecomorphs. Overall, that all study species engaged in controlled aerial descent despite exhibiting substantial morphological variation and being phylogenetically distant within the genus. These results suggest that controlled aerial behaviors may be widespread within Anolis, and that morphological differentiation among species may derive in part from selection for locomotor performance in the air.