Meeting Abstract

30.4  Jan. 5  A combined analysis of variation in skull shape and feeding kinematics in five turtle species STAYTON, C.T.; Bucknell University tstayton@bucknell.edu

Organismal morphology and kinematics interact to produce complex behaviors; however, morphological and kinematic data have traditionally been analyzed separately using different techniques. Here, I present a joint study of the morphology and kinematics of a relatively simple behavior: turtle biting during feeding. Skull morphology and biting kinematics were studied in 5 species of turtles: Chrysemys picta, Sternotherus odoratus, Glyptemys guttata, Graptemys kohnii, and Trachemys scripta. Each species overlaps with the others in some part of its geographic range save G. guttata/G. kohnii. Variation in skull morphology was studied using geometric morphometric techniques on a large data set of preserved skulls. High-speed video was taken of turtles feeding, and kinematic variation was studied using Procrustes motion analysis. These turtles show significant amounts of overlap in both morphology and kinematics, especially among the relatively closely related Emydids (i.e., it is difficult to discriminate the species based on skull shape or kinematics alone). However, when both morphological and kinematic data sets are combined, the observed overlap decreases. An integrated analysis of both types of data can provide valuable information about the evolution and integration of organismal form and function.