Meeting Abstract

70.1  Tuesday, Jan. 6  Patterns of Variation in Chiropteran Wing Folding: With Special Attention to Differences in Joint Morphology ARMOUR, Maria T.; C.W. Post Campus of Long Island University m.t.armour@gmail.com

Bats (Chiroptera) are a diverse group, with more than 1,200 species worldwide, and flight is the synapomorphy that has permitted them to diversify in habitat, behavior, and morphology. All species of bat are similarly equipped with a handwing structure that houses the morphology needed to perform powered flight. Each bat must abide by the same aeromechanical demands placed on them during flight, yet the morphology of their wing structures exhibit significant interspecific variability. Previous phylogenetic studies of Chiroptera have identified differences in wing folding at the family level. This is the first broad-scale study focused on variability at the species level. I examined wing folding-related characteristics across 300 bat species, covering 18 families. Four basic wing folding patterns were described. Digital osteology was studied, in a subset of thirteen species, where I identified aspects of joint morphology involved in those four wing folding patterns. Morphological results showed extreme variation along articulating points of the handwing bones among bat species with correlations between joint morphology and wing folding patterns. The data collected have enabled me to approach several questions including: how do skeletal elements of the handwing vary among species, are there morphological suites of characters arising independently in different lineages, and does flexion pattern along the digits occur independently from the requirements of flight? Interpretation of these data supports my hypothesis that the handwing’s joint composition varies across wing folding states.