托福口语 Task 4

Today we're going to talk about a fascinating concept in animal behavior called 'tool use'. While we often think of tool use as a uniquely human trait, many animals have evolved remarkable abilities to use objects in their environment to solve problems. One key point I want to emphasize is that tool use in animals is not random or instinctive—it often involves learning and adaptation to specific ecological pressures. Let me give you two examples. The first is the sea otter. Sea otters float on their backs and use stones to crack open hard-shelled prey like clams and sea urchins. They place the stone on their chest and repeatedly smash the shell against it. Interestingly, they choose stones of appropriate size and shape, and even keep a favorite stone in their armpit pouch. This shows problem-solving and planning. The second example is the New Caledonian crow. These crows manufacture hooks from twigs and leaves to extract insects from tree crevices. They carefully trim and shape the material, and even pass this technique to their offspring through social learning. This is not just using a tool—it's making one, which requires advanced cognitive skills.