Quantitative comparisons of body form and allometry in larval and adult Pacific sculpins (Teleostei: Cottidae)

Abstract

Morphometric analyses of body form were performed on samples of larvae and adults of five Pacific sculpin species (Ascelichthys rhodorus, Clinocottus acuticeps, Enophrys bison, Nautichthys oculofasciatus, and Rhamphocottus richardsoni) to investigate patterns of interspecific variation, intraspecific differences in allometry between larvae and adults, and relative shape changes that occur in the transformation from larva to adult. Within species, larvae are relatively more variable at a given size than adults, while adults are more variable among species because of divergence during development. Much nonallometric change in shape occurs during transformation, but the relative amount of change varies among species. The direction of change during transformation is not predictable from larval morphology alone. Some pairs of species become convergently similar during transformation, some change in parallel, and others become highly divergent in form.