Correlation of Salamander Vomeronasal and Main Olfactory System Anatomy with Habitat and Sex: Behavioral Interpretations

Abstract

The salamander family Plethodontidae is an ancient group of vertebrates whose members probably rely on a combination of visual and chemical cues for their perception of the world (Roth, 1986). Chemical cues have been shown to be important in a number of social interactions including territoriality (Jaeger, 1986), mate recognition and choice (Dawley, 1986), and “persuasion” during courtship (Houck and Reagan, 1990). Similar to most other terrestrial vertebrates, plethodontid salamanders have both main olfactory and vomeronasal systems that are physically, and perhaps functionally, separate from one another (Dawley and Bass, 1988; Schmidt, Naujoks-Manteuffel, and Roth, 1988). The vomeronasal system is of particular interest for this group of animals because a unique structure (nasolabial grooves) coupled with a unique behavior (nose-tapping) is used to stimulate the vomeronasal system during many social interactions, including mating. In this paper I present a preliminary survey of variation of vomeronasal and main olfactory system morphometrics for salamanders with different habitat requirements and for both sexes. I attempt to correlate this anatomical variation with ecological and sexually dimorphic behavioral variation.