Meeting Abstract

77-3   14:00 - 14:15  Sexy robots and the significance of nuptial coloration in Galápagos lava lizards on San Cristóbal Island Clark, DL*; Macedonia, JM; Rowe, JW; Valle, CA; Alma College, Alma, MI; Florida Southern College, Lakeland, FL; Alma College, Alma, MI; Universidad San Francisco de Quito, Colegio de Ciencias Biológicas y Ambientales, Quito, Ecuador clarkd@alma.edu

In some lizard species females exhibit conspicuous coloration during the breeding cycle (“nuptial coloration”). We conducted experiments with adult male and female Galápagos lava lizards on San Cristóbal Island (Microlophus bivittatus) to determine how the presence and extent of the red nuptial coloration of females, affected subjects’ responses. First, using a MIDI controller, robotic female lizard stimuli were programmed to perform the species typical conspecific pushup display. Then, three different color variant models were created: a) a “non-red” control stimulus; b) “normal red” stimulus; and c) a “super-normal red” stimulus. Two different experiments were conducted: Experiment 1 - each subject witnessed two consecutive stimuli; the non-red and the normal red stimulus, and Experiment 2 - subjects were shown a single stimulus; either a non-red, normal red, or super-normal red robot. Results of Experiment 1 showed no effect of subject sex or stimulus order, but subjects exhibited significantly more display and shorter display latencies in response to the normal red stimulus than to the non-red (control) stimulus. Results of Experiment 2 revealed sex differences in subjects’ responses. Males responded equivalently to the non-red and normal red stimuli, but exhibited significantly less display to the super-normal stimulus. In contrast, female subjects responded with increasing amounts of display to stimuli with increased amounts of red nuptial coloration. In conclusion, response to nuptial coloration varies with gender of test subjects.