Meeting Abstract
P2.54 Monday, Jan. 5 Histology and Morphology of Cyprinid Pharyngeal Dentition in Relation to Diet MOSTAFIZ, W.; GIDMARK, N.*; SWARTZ, S.; Harvard School of Dental Medicine; Brown University; Brown University Whitney.Mostafiz@gmail.com
Many characteristics define the dietary habits and functions of a particular species. Furthermore, the underlying functional bases of the ability to detect, pursue, capture, and to successfully handle prey may relate directly to morphology (Wainwright, 1988). Most studies focus on oral teeth and their relation to diet and dentition, while few studies consider the properties of pharyngeal teeth and also consider their dietary function. In particular, specialized cusps are one essential aspect of tooth shape that relates to wear. Cuspal wear correlates with the direction of masticatory movements and forces and exhibits the thicker enamel layers. This suggests that the cusps themselves are functionally adapted to masticate food, which enables teeth to withstand the usual stresses of mastication (Luke and Lucas, 1983). It has been hypothesized that evolutionary shifts to morphologies associated with herbivory, particularly flattened cusps, occurred simultaneously in multiple cyprinid lineages (Gidmark and Simons, in prep). We examined the morphological and histological features of species in the Erimystax and Pimephales clades, members of the Cyprinidae. Cross-sections of the cusps were stained and imaged, and scanning electron microscopy images of whole tooth rows were obtained. With regard to evolutionary influences, observational data were incorporated into and analyzed with consideration for each clade’s established phylogenetic tree. Herbivorous taxa exhibited modified cusps that were worn, flattened, and possessed an additional layer of tissue. Meanwhile, all carnivorous taxa had one tissue layer and were morphologically diverse. Carnivorous Pimephales taxa exhibited concave cusp bodies. These characteristics in cyprinid fishes support a strong correlation between herbivorous diets and functional morphological and histological adaptations.
