TREE lab alums Andrea (Andy) Aparicio Ramirez and Karina Perez just had their research from the lab published in the Journal of Experimental Zoology. The paper began as Andy’s honors thesis research and explores how Crested Geckos (Correlophus ciliatus) thermoregulate and are affected by the thermal environment.
Crested Geckos were though to be extinct for ~100 years, but were rediscovered in New Caledonia (an island off the coast of Australia) in the mid 1990s. Over a two-year period a few animals were exported from New Caledonia to Europe and the US before export was banned. However, it turns out this species thrives in captivity and the decedents of those originally exported individuals now represent one of the most popular species in the commercial pet trade. Despite their popularity as pets, very little is known about the biology of this species, which only naturally occurs in a few isolated parts of New Caledonia.
In their research, Andy and Karina discovered that Crested Geckos actively thermoregulate to body temperatures of 24-28°C, and only voluntarily allow their body temperatures to get as high as 33°C. These preferred temperatures correspond closely to temperatures naturally available in New Caledonia, suggesting that the lizards rarely need to thermoregulate in nature. Surprisingly, though, the animals perform best (i.e. run fastest) at 32°C, which is well above preferred body temperatures and corresponds to the maximum body temperatures ever allowed.
Comparison of thermoregulatory behavior and thermal performance in crested geckos. Top: distribution of body temperatures experienced in a thermal gradient with preferred body temperature (PBT), voluntary thermal minimum (VTmin) and voluntary thermal maximum (VTmax) shown. Shaded regions are 95% confidence intervals. Bottom: thermal performance curve for running performance. points are whiskers are means and 95%CI at five test temperatures. Inset picture is a crested gecko.
For additional details, check out the paper: Aparicio Ramirez et al 2020 JEZA