Morphology of the Masticatory Apparatus in the Springhare, Pedetes capensis

Publisher Website
Google Scholar
Abstract
Springhares, Pedetes capensis, are adapted for nocturnal life in arid and semiarid regions. Their large orbits and acoustic apparatus differ greatly from the primitive conditions for rodents. Herein, the masticatory apparatus of springhares is compared with the scarce data available for protrogomorph, myomorph, and hystricomorph rodents. The muscles of the zygomasseteric complex are of the hystricomorphous type and show an extremely strong development (87.5% of the total mass of the adductor muscles) compared to the hystricognathous hystricomorphous rodents (66.4% in Cavia). The digastric muscle and the medial pterygoid, in contrast, are of the sciurognathous type. Within each evolutionary line the musculature differs only in detail, whereas masticatory movement patterns vary significantly. Apparently, skeletal elements of the masticatory apparatus significantly affect the movement pattern of the lower jaw during the power stroke during which the molar teeth come into occlusion.