Can Fin Shape Explain Variation in Somatic Growth Among Shark Species?

Across vertebrate taxa, morphology is related to function. An example from fishes is that caudal fin shape relates with swimming speed and activity level, with more elongated fins indicative of fast, active species and rounded fins slower, inactive ones. There is evidence that activity levels correlate with food consumption (more active fish eat more prey), and given that food consumption is relative to somatic growth rate (the more you eat the faster you grow), it might be possible to explain observed variation in growth among species based on a simple measure of fin morphology: caudal fin aspect ratio. Here we present a framework for exploring the relationship between somatic growth rate, maximum size and aspect ratio among a range of shark species, and discuss preliminary findings.