Question: Using the examples from the lecture, explain the professor's main point about how animals use safety in numbers to reduce predation risk.
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Today, we're going to talk about a fascinating concept in animal behavior called 'safety in numbers.' This idea suggests that animals often gather in large groups not just for social reasons, but primarily to reduce their individual risk of being attacked by predators. The key is that by being in a crowd, each animal's chance of being the one targeted drops significantly. Let me give you two clear examples. First, consider the sardine run in the ocean. When a school of sardines is attacked by predators like tuna or dolphins, they form a massive, tight ball. This confuses the predators, making it hard to single out one fish. The predators often just take a few from the edge, so the risk for each sardine is very low. Second, think about wildebeests on the African savanna. When lions hunt, they prefer to target old, sick, or young individuals that are isolated from the main herd. A large herd of wildebeests means that the lions have to chase the herd, and it's harder for them to pick a specific weak member because the healthy ones protect the vulnerable ones in the middle. So, in both cases, the sheer numbers provide a kind of protection.