Meeting Abstract
Protein pheromones are undergoing rapid directional selection in salamanders of the genus Plethodon. Variation in mate recognition components, such as the sex-specific pheromones used by plethodontid salamanders may play a role in sexual incompatibility and therefore the maintenance of isolated, genetically distinct populations. Recent studies suggest that multiple, distinct lineages of Plethodon cinereus are present throughout their range. Three of these lineages are represented in northern Ohio, located along the southern shore of Lake Erie. This distribution creates a unique opportunity to study differences within species and across populations. The three goals of this study were to (1) determine if the ability of males to recognize potential mates is equal within and between lineages, (2) characterize the pheromone profile of P. cinereus and interpret this in the context of pheromone delivery evolution and (3) make a comparison of pheromone profiles across populations of the three distinct lineages within P. cinereus in Ohio. Male P. cinereus were collected from 9 localities across northern Ohio (3 populations from each lineage). To test the ability of animals in each lineage to recognize potential mates, males were exposed to the odors of both sympatric and allopatric females, as well as an odorless control. Recognition of these scents was quantified using the number of nose taps performed by the male during a 15 minute observational trial. Pooled samples of male courtship pheromones from each population were biochemically characterized and relative ratios of specific pheromone isoforms were compared across groups.
