托福口语 Task 4

Today we're going to talk about a fascinating behavioral adaptation in animals called 'safety in numbers.' The main idea is that some animals gather in large groups not just for social reasons, but specifically to reduce their individual risk of being attacked by predators. This strategy works in two main ways, and I'll give you an example for each. First, there's the 'dilution effect.' When a predator attacks a group, the chance that any single individual gets caught is lower because the predator can only take one or two prey at a time. Think of schooling fish, like sardines. When a tuna attacks a massive school of sardines, it only catches a few, so the majority escape. The more sardines there are, the smaller the risk for each one. Second, there's the 'confusion effect.' A large, moving group can overwhelm a predator's senses, making it hard to focus on a single target. For example, when a flock of starlings performs a swirling murmuration, a hawk trying to pick out one bird gets confused by the constant motion and often fails to catch any. So, in both cases, grouping offers a clear survival advantage.