DOI: 10.5061/dryad.d51c5b0cx
title: Thermal ecology and thermal landscape of Sauromalus varius

description: Dataset shows data on the thermal ecology and thermal landscape of the
 piebald chuckwalla, Sauromalus varius, an herbivorous reptile living on a
 hot desert island in one of the warmest areas in the world. Data was
 collected during the warmest period of the year (July 2023). We recorded
 field body temperature (Tbfield), voluntary thermal limits (the voluntary
 maximum body temperature), the onset of thermal stress responses (e.g.,
 panting), and critical maximum temperature (CTmax) at which righting
 response was lost. We also determined thermal landscape available to the
 iguanas on the island. Temperature dataloggers registered temperature
 every 30 min during six days in the hottest month of the year. Temperature
 was determined for air temperature (at 150 cm above the substrate) and in
 the sun (30 cm above the substrate), and for microhabitats available to
 the iguana: substrate temperature in the sun and shade, under plants,
 under rocks, and in caves.
description: Data on the thermal requirements of the piebald iguana
 <em>Sauromalus varius</em> during the hottest time of the year
 and its thermal landscape on the island San Esteban, Sonora,
 Mexico. During July 2023 thermal requirements of 15
 piebald iguanas, <em>Sauromalus varius</em>, were determined
 through tests on the island San Esteban, Sonora, Mexico. We obtained field
 body temperature (measured immediately after capture), maximum voluntary
 body temperature (at which the iguana sought shade), and maximum critical
 temperature (at which the iguana lost the righting response). Further, we
 registered the temperature at the onset of gaping (evaporative heat loss),
 production of feces, and spasms in the head muscles, signals of thermal
 stress. Also, time to reach these temperatures was recorded.
 In July 2023, 32 dataloggers registered temperatures in
 microclimates on the island San Esteban, Sonora, Mexico. Dataloggers
 registered temperature every 30 min over 5 days. Data was obtained from
 air temperature (at 150 cm above surface; 2 dataloggers), temperature in
 the sun (30 cm above surface; 3 dataloggers), substrate temperature in the
 sun (2 dataloggers) and in the shade (2 dataloggers), temperature in the
 shade of plants without leaves (7 dataloggers) and plants with leaves (6
 dataloggers), temperature below rocks (5 dataloggers), and temperature in
 caves (4 dataloggers).
description: # Thermal ecology and thermal landscape of Sauromalus varius
 [https://doi.org/10.5061/dryad.d51c5b0cx](https://doi.org/10.5061/dryad.d51c5b0cx) ## Description of the data and file structure **Files and variables** **File: Thermal_ecology_and_thermal_landscape_of_Sauromalus_varius.xlsx** The dataset is presented in an excel file with three sheets. The sheet called "Definitions" shows a list of all variables used with their definition and unit of measurement. The sheet called "Sauromalus data" includes morphological data on the individuals included in this study and data on their thermal requirements and limits. The sheet called "Temperature data" shows raw data of the temperatures recorded in the 32 dataloggers included in this study.  Variables (for a complete list and further information on measurements see the sheet "Definitions"):  Variables  Missing values are indicated by NA             ### Sauromalus data:        Sex: Sex of the individual (male or female) SVL: Snout vent length (mm) Bodymass: Body mass (g) FieldTb: Body temperature measured immediately after capture (°C) Tpanting: Temperature at the unset of panting  (°C) CTmax: Maximum critical temperature (°C) Tfeces: Temperature at which feces were produced (°C) Theadspasms: Temperature at which head spasms were observed (°C) VTM: Maximum voluntary temperature (°C) ### Temperature data:       Date_and_time: Date and time of the recorded temperature (dd:mm:yy, hh:mm:ss) Air: Air temperature at 150 cm above the substrate  (°C) Sun: Temperature in the sun at 30 cm from the substrate  (°C) Substrate_sun: Temperature of sun exposed substrate (°C) Substrate_shade: Temperature of substrate in shade (°C) Bushwithoutleaves: Temperature below a bush without leaves (°C) Bushwithleaves: Temperature below a bush with leaves (°C) Rock: Temperature below a rock (°C) Cave: Temperatures measured in a cave (°C) Empty cells indicate no data is available.