Many amphibians are known to be arboreal, living in trees. Controlled aerial descent by parachuting (i.e., manipulating falling speed) or gliding (i.e., generating a horizontal component of locomotion while descending) is common among arboreal animals, yet until recently, had been unexplored in salamanders. Brown et al. (2022) documented controlled aerial descent in the highly arboreal Aneides vagrans, which lives in the canopies of the tallest trees on Earth, as well as in three other related species representing a continuum of arboreality: A. lugubris (most arboreal after A. vagrans), A. flavipunctatus, and Ensatina eschscholtzii (least arboreal). The authors used a vertical wind tunnel to simulate aerial descent and motion capture techniques to characterize their behaviors. The more arboreal species (A. lugubris and A. vagrans) regularly demonstrated aerial control by adjusting body orientation, parachuting, and gliding. Alternatively, A. flavipunctatus and E. eschscholtzii rarely showed such control. This is the first instance in which salamanders have been demonstrated to perform such behaviors, which they do without specialized aerodynamic control surfaces like skin flaps. It is possible that the morphological features typically associated with arboreality, such as relatively flattened body, long limbs and digits, and large feet relative to body size, serve to enhance aerial control. Further investigation into such inconspicuous aerodynamic features may reveal similar adaptations in other arboreal taxa.
