托福口语 Task 4

Today, we're going to talk about a concept in biology called 'behavioral thermoregulation.' This is when animals actively change their behavior to control their body temperature, rather than relying solely on physiological mechanisms like sweating or shivering. Let me give you two examples to illustrate this. First, consider the desert iguana, a lizard that lives in the scorching American Southwest. During the hottest part of the day, when the ground temperature can exceed 50 degrees Celsius, the iguana doesn't just sit there baking. Instead, it climbs up onto rocks or into crevices where the temperature is cooler, and it may even raise its body off the hot surface by standing on its toes. This behavior helps it avoid overheating. Second, think about honeybees. In a hive, the temperature must be kept steady around 35 degrees Celsius for the larvae to survive. On a very hot day, worker bees will gather water and spread it thinly over the comb, then fan their wings to create airflow, which cools the hive through evaporation. On cold days, they cluster together and shiver their flight muscles to generate heat. So, in both cases, the animals use specific actions to regulate their thermal environment.