Meeting Abstract

102.6  Sunday, Jan. 6  Scaling of radular length and replacement rate in the Atlantic slippersnail, Crepidula fornicata. PADILLA, D.K.*; YEE, A.; Stony Brook University; Stony Brook University padilla@life.bio.sunysb.edu

All organisms undergo changes in size during ontogeny, and, for multicellular animals, morphologies, behavior and performance frequently do not scale simply with size. In addition, throughout ontogeny organisms experience significant changes in their biotic and abiotic environments, and can respond through changes in morphological, physiological and behavioral traits, or phenotypic plasticity. Morphological systems often have size-dependent functions, i.e., all features of organisms cannot be expected to function similarly as individuals change size through ontogeny, creating challenges for organisms with respect food acquisition among other functions. The slippersnial Crepidula fornicata is unusual among gastropods in that it is primarily a suspension feeder. It does possess a radula, which is used to move collected food particles, primarily microalgae, bound in strings of mucus into the digestive track. However, some data suggest that very small snails retain the ancestral feeding mode of grazing with the radula. We examined the scaling of radular length with body size in C. fornicata from newly metamorphosed juveniles to adults, and quantified radular replacement rates for snails across a wide size range. We found that the radula of C. fornicata is shorter relative to body size than many other gastropods with a similar radular form, and that smaller snails have a disproportionately long radula relative to larger snails when compared to other grazers. The rate of tooth replacement in C. fornicata was around 0.59 rows per day, much slower than other grazing gastropods. Differences in radular morphology were also found among individuals, suggesting the possibility of radular tooth phenotypic plasticity as well.