Biting Performance in Teeth‐Digging African Mole‐Rats (Fukomys, Bathyergidae, Rodentia)

Abstract

Phenotypic variation is channeled by adaptation to local environments and phylogenetic constraints. The morphology of the obligatorily subterranean African mole-rats of the genus Fukomys has been shaped within the context of their underground habitat, posing particular limits on the animals' morphology. Especially the biting apparatus has likely evolved within severe evolutionary constraints, as it is used for feeding on hard geophytes, for digging complex tunnel systems, and for defensive purposes and social interactions in a colony. We studied interspecific differences in bite performance among three taxa, in relation to their skull anatomy and skull shape. Data on biting performance were gathered by in vivo measurements and compared with model simulations. It is shown that the model simulation is a good proxy for in vivo measurement. Scaling of bite force is positively allometric relative to head size. Moreover, differences in biting performance exist between taxa, which may be linked to differences in their ecology. This study will eventually enable us to analyze the evolutionary pattern behind the variation in structure and performance of the biting apparatus in Fukomys mole-rats.

Ontogenetic changes in jaw-muscle architecture facilitate durophagy in the turtleSternotherus minor

“…This is consistent with other static bite-force models that assume simultaneous and maximum contraction of the adductor musculature during biting (e.g. Wainwright, 1987;Hernández and Motta, 1997;Van Daele et al, 2009;Curtis et al, 2010). We understand that this does not account for the full range of functional variation in muscle recruitment (De Vree and Gans, 1984;Gans et al, 1985;Cleuren et al, 1995).…”

Analysis of arch‐like bones: The rodent mandible as a case study

“…The mandibular apparatus of rodents, which is adapted to process hard food items, is particularly capable of producing strong bite forces (Van Daele et al, 2009;Becerra et al, 2012;Vassallo and Antenucci, 2015). Therefore, it must be able to withstand large reaction forces received on incisors, molars, and jaw condyle.…”

Digital dissection of the masticatory muscles of the naked mole-rat,Heterocephalus glaber(Mammalia, Rodentia)

“…This morphology is termed protrogomorphous, and is thought to be the ancestral condition for rodents also seen in many Eocene fossil taxa (Wood, 1965) and the extant mountain beaver, Aplodontia rufa (Druzinsky, 2010), although claims of hystricomorphy in Aplodontia have also been made (Eastman, 1982). It should be noted, however, that a moderate enlargement of the infraorbital foramen is seen in two recently-split extant genera of blesmols, Cryptomys (Boller, 1970; Morlok, 1983) and Fukomys (Van Daele, Herrel & Adriaens, 2009), as well as in fossil genera from the Miocene of East Africa, (Lavocat, 1973; Lavocat, 1974). In Cryptomys and Fukomys this enlargement is accompanied by a very limited extension of the ZM through the foramen on to the rostrum (Boller, 1970; Van Daele, Herrel & Adriaens, 2009).…”