Meeting Abstract

P3.94  Sunday, Jan. 6  Pulmonary anatomy and the evolution of turtles SCHACHNER, ER*; LYSON, TR; FARMER, CG; University of Utah; Smithsonian Institution; University of Utah eschachner@gmail.com

A fundamental question in evolutionary morphology is the origin of the structural diversity in the amniote lung. A second, and equally as contentious question within biology is the phylogenetic position of turtles. Recent studies have placed turtles outside of Diapsida based upon paleontological characters; however, several recent molecular-based analyses place them as a sister group to archosaurs. Pulmonary anatomy has long been used as a phylogenetic character for many vertebrates (e.g., varanids, chamaeleonids, anguimorph lizards, and rodents), yet there remains to be any detailed investigation into the pulmonary anatomy of turtles with the aim of contributing to the phylogenetic debate. The anatomy of the primary, secondary, and tertiary pulmonary bronchi of multiple genera of turtles were visualized as 3D surface models using computed tomography (CT). This method provides a novel way to analyze the respiratory system in situ, which will further elucidate the unusual morphology of turtle lungs as well as contribute to the discussion on the evolution of Testudines.