The influence of age on taste disc density and size in the toad Incilius alvarius (Lissamphibia: Bufonidae)

Abstract

We investigated the distribution and morphology of taste organs of the Colorado River toad, Incilius alvarius, in a comparative approach. We also examined whether the age of metamorphosed individuals affected taste disc density and the area of sensory zones. Although taste disc morphology appeared similar to previously studied bufonids, we demonstrateed that taste disc density on the tongue may decrease with age, while the area of taste disc sensory zones may increase. This is consistent with a recent study on a direct developing anuran. Therefore we hypothesize that each individual bears a limited pool of taste organs.