TOEFL Speaking Task 3

In biology, the term “behavioral adaptation” refers to an action an organism takes to increase its chances of survival and reproduction in its environment. Unlike physical adaptations, which involve body structures, behavioral adaptations are learned or instinctive responses to specific environmental challenges. These behaviors can include migration, hunting strategies, or social cooperation. They are shaped by natural selection because individuals with behaviors that help them survive are more likely to pass on their genes. Behavioral adaptations are often triggered by changes in the environment, such as temperature shifts, food scarcity, or the presence of predators.

Professor: Let me give you a concrete example from a study on desert lizards. These lizards live in very hot, dry environments where midday temperatures can exceed lethal limits. When the sun is at its peak, the ground becomes too hot for them to walk on without burning their feet. So what do they do? They adopt a behavior called “thermal stilt walking.” They lift their bodies as high off the ground as possible and move quickly from one shaded spot to another. This is not something they are born knowing—they learn it by trial and error as juveniles. By minimizing contact with the hot surface and moving during cooler hours, they avoid overheating and reduce water loss. This behavior directly increases their chance of survival, allowing them to reproduce and pass on this tendency. So you see, the stilt walking is a perfect example of a behavioral adaptation.