DURIE, C.J.*; TURINGAN, R.G.: Relationship between durophagy and feeding functional design in marine fishes: intraspecific variation in ecological morphology

The relationship between oral jaw biomechanics and consumption of hard prey was compared between populations of two perciform and five tetraodontiform species to examine intraspecific ecomorphological variation in marine fishes. Gut content analysis revealed that the magnitude of durophagy (feeding on hard-shelled invertebrates, such as crabs and sea urchins) varied between populations of each species. Difference in the relative magnitude of durophagy between populations was associated with intraspecific differences in key biomechanical properties of the prey-capture and processing mechanisms. The more durophagous populations had more massive jaw bones and muscles than conspecifics that consumed soft prey. We hypothesize that marine fishes have the ability to alter the development of their feeding mechanism to match the requirements for capturing and processing locally availabe prey-resources at post-recruitment habitats, such as coral reefs and estuaries.