Asbury, Dee (2003)
Use of Perch Height in Regard to Thermoregulation in Sceloporus occidentalis: Population Comparisons.
Bachelor of Science, Harvey Mudd College, Biology.
Advisor: Stephen Adolph.
I investigated perch height choices in three populations of western fence lizards (Sceloporus occidentalis) with habitats varying in altitude (from 400 m to 2230 m) and climate (desert, moderate, and mountain). Perching behavior was observed both in the field and in experimental enclosures at the Bernard Field Station, Claremont, CA. In nature, S. occidentalis perching behavior varied significantly with higher perch choice coinciding with warmer average temperatures. In the field experiments where the three populations were exposed to the same environmental factors, perching behavior did not differ between populations. These results indicate that population differences in perch choice is a plastic behavior, variable in response to some environmental factor, rather than learned or genetic.