托福口语 Task 4

Today we're going to talk about a fascinating concept in animal behavior called 'safety in numbers.' This is the idea that animals often gather in groups not just for social reasons, but primarily to reduce their individual risk of being attacked by predators. The main point is that by being in a large group, each individual's chance of being the one that gets caught decreases, and predators may become confused or deterred. Let me give you two examples. First, consider the schooling behavior of sardines. When a predator like a tuna approaches, thousands of sardines form a tight, swirling ball. This makes it hard for the tuna to single out one fish. The constant movement confuses the predator, and the sheer number of fish overwhelms its ability to focus. Even if the tuna manages to catch some, the majority escape. Second, think about wildebeests during migration. When lions hunt, they typically target the young, old, or sick individuals that are isolated from the herd. The herd itself acts as a protective barrier. The wildebeests run together in a dense mass, making it difficult for lions to isolate a healthy adult. The lions often give up if they can't separate a weak one quickly, because the effort is too high. So in both cases, grouping significantly lowers the risk for the individual.