托福口语 Task 4

Today we're going to talk about a fascinating concept in animal behavior known as 'biological altruism' – when an animal acts in a way that benefits another individual at its own expense. Now, you might think this contradicts the idea of survival of the fittest, but it actually makes sense from an evolutionary perspective. Let me give you two examples. First, consider ground squirrels. When a predator like a hawk approaches, a squirrel will often give a loud alarm call, even though this draws attention to itself and increases its own risk of being attacked. However, the call warns other squirrels, especially its relatives, to hide. Since relatives share many of the same genes, by protecting them, the squirrel is indirectly ensuring that its own genes are passed on. Second, think about vampire bats. These bats need to feed on blood every night, but sometimes a bat fails to find a meal. In such cases, a successful bat will regurgitate some blood to feed the hungry bat, even if it means going hungry itself. Interestingly, bats are more likely to help those who have helped them before. This reciprocal altruism ensures that in the long run, all bats in the group benefit, increasing their chances of survival.