Meeting Abstract

P1-106   -   Evolution of the Vertebral Column and the Position of the Heart in Boids and Pythonids Fundingsland, TJ*; Hampton, PM; Colorado Mesa University; Colorado Mesa University tjfundingsland@mavs.coloradomesa.edu

In previous studies, it has been proposed that the position of the heart in snakes is generally considered to be associated with primary habitat use and the physiological constraints for blood pressure homeostasis. However, boids and pythonids comprise a relatively small proportion of the taxa in these studies. Moreover, boids and pythonids are unique among snakes with exceptionally large body sizes and high number of vertebrae. Consequently, statistical conclusions on the ubiquity of snake ecomorphology may be driven by larger snake families which may not hold true for such morphologically disparate taxa when evaluated in isolation. We measured the pre-cloacal and caudal regions of the vertebral column as well as heart position in boids and pythonids using both linear measurements and scale counts. We tested for dissociation in the number of vertebrae between the head and the heart, the heart and cloaca and between the pre-cloacal vertebrae and caudal vertebrae. In addition, we investigated ecological factors driving changes in the relative lengths and the proportion of vertebrae among the three regions of the vertebral column. Results will be discussed.