托福口语 Task 3

In biology, the term 'behavioral thermoregulation' refers to the actions an animal takes to control its body temperature by moving to different environments. Unlike physiological mechanisms, such as sweating or shivering, behavioral thermoregulation involves deliberate choices about where and when to be active. This strategy is common among ectotherms, or cold-blooded animals, which rely on external heat sources. By selecting warmer or cooler microhabitats, they can maintain an optimal internal temperature for vital functions like digestion and movement. This concept highlights how animals actively manage their thermal environment.

Professor: Let me give you a clear example from a desert lizard. In the early morning, the desert is cool, so the lizard emerges from its burrow and lies on a sun-warmed rock. This position allows it to absorb heat, raising its body temperature quickly. As the midday sun intensifies, the rock becomes too hot. The lizard then moves into the shade under a bush or crawls into a crack in the ground, avoiding overheating. In the late afternoon, when temperatures drop again, it returns to an open sunny spot to soak up remaining heat. This way, the lizard keeps its body temperature within a range that allows it to hunt and digest food effectively. The lizard's movement between sunny and shady areas is a perfect example of behavioral thermoregulation.