托福口语 Task 3

In biology, the concept of “behavioral thermoregulation” refers to the deliberate actions animals take to control their body temperature by moving between or utilizing different environments. Unlike physiological mechanisms such as sweating or shivering, behavioral thermoregulation involves conscious choices that help an animal maintain an optimal internal temperature for survival and activity. This can include seeking shade, basking in the sun, or changing posture to expose more or less body surface to heat sources.

Professor: So, let’s look at a real example. Consider the desert iguana, a lizard that lives in the hot, arid regions of the American Southwest. During the early morning, when the ground is still cool, the iguana emerges from its burrow and lies flat on a sun-warmed rock. It spreads its body out to maximize the surface area exposed to the sun, absorbing heat quickly. But as the day progresses, the temperature rises sharply. To avoid overheating, the iguana then climbs onto a shady perch, such as a bush or a crevice, and raises its body off the hot ground, allowing air to circulate underneath. If it gets too hot even in the shade, it will retreat into its burrow, which remains cooler than the surface. By moving between sunny and shaded spots throughout the day, the iguana keeps its body temperature within a safe range, enabling it to hunt for insects and evade predators effectively.