Meeting Abstract
Climate change is an important agent of selection on physiology and phenology, and can affect the range and distribution of organisms. Organisms may respond to climate change through behavior, genetic adaptation or phenotypic plasticity. However, these predictions are not consistent across latitude. Tropical ectotherms are predicted to be negatively impacted by climate change because 1) most have a narrow range of thermal tolerance while already living close to their thermal optima, and 2) they are thought to have decreased capacity for phenotypic plasticity because they have evolved in thermally stable environments. We used a mesocosm experiment to test the capacity for phenotypic plasticity of the Panamanian slender anole (Anolis apletophallus) under warming temperature. We caught lizards from Soberania National Park and randomly assigned an equal number of males and females to a control and warming treatment. We measured voluntary thermal maxima, critical thermal minima, and behavior in a thermal gradient before and after 28 days of treatment. We found that voluntary thermal maxima and maximum temperature chosen in a thermal gradient increased in the warm treatment, but not the control treatment. In contrast, we found that critical thermal minima and the mean temperature chosen in a thermal gradient decreased in both treatments. Our results provide evidence that tropical organisms can use phenotypic plasticity to respond to a changing climate, despite previous theoretical work suggesting that they lack plastic potential. This work highlights that phenotypic plasticity should be considered when predicting the future of tropical ectotherms under a changing climate.
