TOEFLスピーキング Task 3

In biology, the concept of 'behavioral thermoregulation' refers to the strategies animals use to maintain their body temperature within a favorable range by adjusting their behavior, rather than through internal physiological changes. This can include moving to different environments, changing posture, or altering activity patterns. Behavioral thermoregulation is crucial for ectotherms, which rely on external heat sources, but it is also used by endotherms to conserve energy. The key is that the animal actively chooses behaviors that increase or decrease heat gain or loss.

Professor: Let me give you a concrete example from a study on desert lizards. These lizards are ectotherms, so they need to control their temperature by moving between sun and shade. In the morning, when it's cool, they bask on sun-warmed rocks, flattening their bodies to absorb more heat. As the day heats up, they shift to shaded areas, and if they still get too hot, they climb onto vertical stems of plants to catch cooler breezes. But here's the clever part: when the ground gets extremely hot, they perform 'thermal dancing'—lifting one foot at a time briefly to avoid overheating while moving quickly from one shaded spot to another. This entire sequence of moving, posturing, and timing their activity shows how they actively manage their body heat through behavior.