托福口语 Task 4

Today we're going to talk about a fascinating concept in animal behavior called 'tool use.' Now, when we think of tool use, we often think of humans or primates, but many other animals also use tools in clever ways. The main point I want to make is that tool use in animals is not random; it's a learned behavior that serves a specific purpose, often for obtaining food. Let me give you two examples. First, consider the sea otter. Sea otters float on their backs and use rocks to crack open hard-shelled clams. They place the rock on their chest and repeatedly smash the clam against it. This behavior is not innate; young otters watch their mothers and practice until they master it. Second, take the New Caledonian crow. These crows are famous for crafting hooks from twigs or leaves to extract insects from tree bark. They even modify the shape of the twig to make it more effective. Researchers have observed that crows learn this technique from their parents and local group, showing regional variations. So, both examples illustrate that tool use is an adaptive, learned skill passed down within a species.