Morphological Investigation into Functions of the Jaw Symphysis in Carnivorans

The hemimandibles in carnivorans may be united in various ways at the symphysis menti. The symphysis may contain a readily flexible joint that permits a moderate amount of independent movement of the hemimandibles. This type of symphyseal union is primitive for and widely distributed in extant carnivorans. In other carnivorans, the symphysis is patent but allows slight or essentially no independent movement of the hemimandibles. Finally, the hemimandibles may be rigidly united by synostosis of the symphysis. The morphology, movement and, insofar as possible, function of these types of symphyses are described.