Describe the thermal energy budget of an animal. Do not just list fluxes, describe how each results in heat gain or loss. Black body temperature more accurately characterizes an animal's thermal environment than does air temperature. Black coloration of desert animals may seem thermally maladaptive, yet many desert organisms are dark. Explain how dark color may be beneficial to a darkling beetle and a phainopepla.
Many animals go below ground during the heat of a summer day.
Describe the benefits of such retreats. Bergman's rule states that animals of warmer regions tend to have smaller body sizes. Describe the thermoregulatory and energetic explanations for this trend. Rattlesnakes are active primarily at night during warmer months. Even in absolute darkness, rattlesnakes can detect their warm-blooded prey, rodents being a favorite meal.