Quantitative analysis of feeding kinematics in dusky salamanders (Desmognathus)

Abstract

Gape formation by the dusky salamander(Desmognathus) involves both upper and lower jaws and occurs in a manner similar to that of other terrestrial salamanders. As Desemognathus opens its mouth, ventral rotation of the mandibles is restricted but not stopped by the atlas-mandibular ligaments, the lower jaw is not propelled anteriorly. Tongue protraction, well beyond the mandibular symphysis, is always a major component of prey capture by this genus. After the sticky tongue pad has made contact with the prey, the salamander''s head surges forward and the pad is rapidly retracted with the prey item attached. Aided by a unique suite of characters the mouth then snaps shut with considerable force. Our study supports the premise that Desmognathus is no different from most, if not all, terrestrial salamanders in its employment of tongue projection as a major feature in prey capture. We argue that the primary selective force for the unique configuration of desmognathine cephalic structures was enhancement of the ability of these small salamanders to capture relatively large prey without an increase in the size of the head and body.