Meeting Abstract
Carnivorans share an evolutionary history specializing on a diet of vertebrate prey. As such, they are characterized by a suite of morphological and behavioral specializations that aid in capturing and feeding on animal tissues. However, a few carnivoran species have secondarily specialized on alternative, plant-based diets. In spite of the dietary specialization and diversity among carnivorans, very few studies have investigated their mastication in vivo. The goal of our study was to compare and contrast the masticatory motor pattern of two species of musteloid carnivoran with divergent dietary specializations: a carnivorous mustelid, the ferret (Mustela putorius furo) and a frugivorous procyonid, the kinkajou (Potos flavus). Electromyography was recorded bilaterally from anterior and posterior temporalis, medial pterygoid, and superficial and deep masseter during rhythmic mastication. Pairwise comparisons were used to determine whether timing of peak muscle activity differed between the jaw adductors. Both species exhibited near-simultaneous peak activity of all jaw adductors. This motor pattern is likely to facilitate concentration of muscle force for rapid vertical jaw movements used for slicing animal tissues. However, interspecific differences suggest specializations in the kinkajou motor pattern may be associated with transversely-oriented grinding jaw movements, which may assist them in processing fruit.
