Meeting Abstract
How do evolutionary processes act upon structures that are involved with more than one biomechanical system (“functional coupling”)? Functional coupling has long been thought to constrain morphological evolution, and yet evidence to support this assertion includes only a small number of studies that show increased morphological diversification when functions become decoupled and decreased morphological diversification with the appearance of a new coupling. While these studies are certainly compelling, the question becomes: Does functional coupling always (or even frequently) constrain morphological evolution? To address this question, I define a series of terms to provide a framework for considering morphological evolution in structures that perform multiple functions. I then discuss examples of functional coupling associated with morphological innovation and novelty that have resulted in increased morphological diversification. Finally, I present a study on the evolution of suction feeding and gill ventilation in fishes using measurements from micro-CT scans to demonstrate how sources of relaxed morphological constraint can operate within a system of closely-coupled functions.
