Area of Study
Science and Mathematics
Many pheromones are produced by glands and deposited on substrates throughout the environment. Lizards possess an array of glands that secrete chemical cue. During mating seasons the glandular secretions of many lizards contain elevated levels of lipophilic compounds including: free-fatty acids, sterols, and long-chain fatty alcohols. This study examines the effect of season and hydrophobicity of chemicals on male response to female deposited chemical cues in the Striped Plateau Lizard (Sceloporous virgatus). Cues were collected and then scraped into a vial containing hexane and water in order to separate hydrophilic and lipophilic molecules. Chemical cue fractions were then presented to males along with corresponding solvent controls. Behavioral trials were conducted during both the mating and non-mating season. Lipophilic components of chemical cues were analyzed by GC/MS. Males exhibited a greater rate of chemosensory behaviors during the mating season than the non-mating season. They showed higher rates of chemosensory behaviors directed toward the water cue than the hexane cue, but neither cue had a different response than the corresponding control. This indicates that the differences are not due to the dissolved components but due to effects of the solvents themselves, but that they search for chemical cues deposited in the environment during the mating season. GC/MS analysis showed a greater number of compounds to be present in the deposits collected during the mating season than those collected during the non-mating season. The peaks exclusive to the mating season correspond to n-alkanes (C9-C20), sterols, and fatty alcohols.
Goldberg, Jay, "Behavioral and Chemical Analysis of Deposited Chemical Cues in Striped Plateau Lizards" (2012). Summer Research. 170.
University of Puget Sound