Comparative biology of taste: Insights into mechanism and function

Abstract

Each animal lives in its own sensory world that is coordinated with its diet. In this brief review, we describe several examples of this coordination from studies of the sense of taste, particularly from species of the order Carnivora. This order includes species that are obligate carnivores (e.g., Felis species), omnivores, and strict plant eaters. Many of the obligate carnivores have lost function for sweet taste, presumably through relaxation of selection for eating sugars from plants. In contrast, the giant panda, which feeds almost exclusively on bamboo, retains sweet taste function but may have lost amino acid (umami) taste perception. Finally, mammals that have “returned” to the sea, such as sea lions, have experienced even more extensive taste loss, presumably as a consequence of adaptations to a diet of fish and other sea creatures swallowed whole. Future comparative studies will surely reveal important relationships between diet and molecular, cellular, and behavioral taste adaptations that will shed light on how evolution moulds sensory structure and function.