Meeting Abstract
Although reptiles have likely evolved mechanisms to reduce cutaneous water loss (CWL), this remains the main route of evaporative water loss in many species. Despite the importance of CWL to reptiles few studies have quantified the amount of variation in this trait, including its relation to temperature and diel variation. We measured CWL and calculated the skin’s resistance to water loss (Rs) of twenty male Sceloporus consobrinus collected from southwestern Oklahoma in 2014 and 2015. The goals of this study were to determine 1) how rates of CWL and Rs are affected by temperature, 2) how rates of CWL and Rs vary throughout the day and 3) the repeatability of CWL within a sampling period. To determine the effect of temperature we recorded three measurements of CWL on the dorsal and ventral side, surface temperature, room temperature and relative humidity at 24°C and 35°C on separate days using a Delfin vapometer. We also measured the same parameters on each lizard three times over seven hours while they behaviorally thermoregulated in their enclosures. We found that 1) lizards at 35°C had lower CWL and higher Rs than lizards at 24°C,but there was a lack of repeatability for both traits across temperatures. We also found 2) a difference in CWL and Rs at different times of the day with inconsistent repeatability measures. Lastly, we found 3) significant repeatability of CWL and Rs within each measuring period as measured by the intraclass correlation coefficient. The lack of repeatability across certain times of day and at different temperatures suggests to us that lizards may be using physiological mechanisms such as altering peripheral blood flow to reduce rates of water loss when in a desiccating environment.
