Meeting Abstract
Ecological studies of reptile development traditionally employed constant incubation temperatures to assess the effect of temperature on embryos and hatchling phenotypes. Constant temperature regimes do not accurately represent natural thermal fluctuations in nests. With the advent of programmable incubators, researchers can simulate nest conditions in the lab. A common method is to construct daily temperature regimes by averaging temperatures recorded at each hour of the day by temperature sensors across multiple nests. Calculating hourly means over multiple nests, however, may obscure some of the variation that exists in natural nests since microenvironmental conditions affect how nest temperatures rise and fall at different rates across the landscape. To address this, we used temperature data recorded from 22 nest sites of anole lizards (Anolis cristatellus and Anolis sagrei) over a period of 43 days. We created two 24-hour daily temperature fluctuations. One was created by taking hourly mean temperatures across all nests. A second used the same nest data, but we first aligned the peak temperatures of each nest prior to calculating hourly means. This method better approximates the natural daily rise and fall of temperature. These regimes had the same mean temperature but differed in how rapidly temperature rose and fell throughout the day as well as the maximum daily temperature. We randomly distributed eggs from a captive colony of anoles to incubate at each regime and measured developmental rate, water uptake, and hatchling morphology. We found no significant effect of incubation treatment on developmental rates, water uptake, or hatchling phenotype for either species. Our results suggest that researchers have some flexibility in how they replicate nest conditions in the lab.
