Date of Award


Document Type

Open Access



First Advisor

Leo Fleishman




lizards anoles headbob "honest signaling" temperature


Anolis sagrei, or the brown anole, is a lizard endemic to the Antilles that produces headbob displays for territorial aggression and sexual attraction. It has been hypothesized that these displays are honest signals of body condition, so they are evolutionarily more likely to garner attention and a response from receivers. In this study, we looked at the effects of body temperature on the display by controlling the body temperature during territorial headbob displays. We examined whether the speed (or abruptness) of display motion patterns was altered by changes in body temperature. In another experiment we tested whether or not the lizards could sense a small difference in the speed of display movements. We also directly stimulated the gastrocnemius muscle to see if it inherently had a direction-changing motion pattern. Results indicated no significant difference in temperature effects or ability to sense those slower display movements. This could indicate that Anolis sagrei is less temperature-sensitive than initially thought, which could have important implications for conservation in terms of the threat of climate change. We also looked at the effects of rapid shifts in direction of motion observed in the visual displays. The motion stimulus experiment revealed no significant difference between direction-changing elements and nondirection-changing elements. However, the muscle stimulation did not show any presence of a direction-changing element. These results are unclear with regard to the evolution of the direction-changing element in the Anolis sagrei headbob display.



Rights Statement

In Copyright - Educational Use Permitted.