Effect of signaler body size on the response of male striped plateau lizards (Sceloporus virgatus) to conspecific chemical cues
Journal of Herpetology
Chemical signals may communicate information about discrete character states, such as species and sex, as well as continuously varying characteristics that affect mate assessment. Here, we investigate whether body size is assessed from chemical cues of Striped Plateau Lizards (Sceloporus virgatus). Preliminary evidence indicated that males may respond to female chemical cues in a size-dependent manner. Because larger females may be more fecund, we hypothesized that in choice tests, males would prefer chemical cues from larger females. We compared male response to pairs of chemical cues obtained from adult females that differed in body size by 12%. Males did not discriminate between cues based solely on relative body size of the donors, but male preference was correlated with the body size of the larger donor female, indicating that absolute body size also played an important role. The preference scores were positive (indicating a preference for the larger female) only when the pair of donor females was relatively large and were negative (indicating a preference for the smaller female) when the donor pair was relatively small. Thus, males had a stronger chemosensory response to cues from the largest “large” females and the smallest “small” females. Overall, male response was more complicated than expected; we did not find a consistent preference for the cue from the largest female, as was expected based on the selective advantage of mating with larger, more fecund females. We suggest that the chemical composition of the female cue may signal additional information such as reproductive state.
Fritzsche*, A.K. and S.L. Weiss. 2012. Effect of signaler body size on the response of male striped plateau lizards (Sceloporus virgatus) to conspecific chemical cues. Journal of Herpetology 46:79-84.