Desert Iguana

Exemplar of ectothermic behavioral thermoregulation, maintaining 100°F body temperature using only 2% of daily caloric intake. Morning: basks on dark rocks. Midday: seeks shade. Afternoon: shuttles between sun and shade. Night: burrows underground. Achieves ±2°F temperature precision at 10% the energy cost of similar-sized mammals, but activity limited to 6 hours/day when environmental temperature is optimal.