Some animals, unlike humans, can dramatically vary their internal temperatures, a trait called heterothermy. The fat-tailed dwarf lemur, for instance, fluctuates its body heat by nearly 45°F (25°C) daily. This flexibility helps them survive extreme conditions like storms, floods, and predator threats.

Researchers, tracking animals with new technology, are discovering this adaptability is more common than once thought. Ecophysiologist Danielle Levesque notes, 'We're finding a lot more weirdness.' The most extreme form is hibernation, but many species use shorter torpor bouts to conserve energy. Bats adjust torpor based on weather, spending more time inactive during wind and rain.

Pregnant hoary bats even pause pregnancies during storms, a survival tactic. This ability is crucial for water conservation; raising body temperature slightly during heat waves saves significant water for small mammals like ringtail possums. The fat-tailed dunnart reduces foraging in high-predation areas, showing how temperature shifts aid survival across diverse threats.