托福听力

🎧 听力原文

Listen to part of a lecture in a biology class. The professor is discussing the concept of mimicry in animals. Professor: Now, when we talk about mimicry, we're usually referring to one species evolving to resemble another. A classic example is the monarch butterfly, which is toxic to predators. The viceroy butterfly, however, is not toxic, but it has evolved to look almost identical to the monarch. This is called Batesian mimicry, where a harmless species mimics a harmful one to avoid being eaten. But there's also Müllerian mimicry, where two or more harmful species evolve to look similar. This benefits all of them because predators learn to avoid the shared appearance more quickly. Now, what's interesting is that mimicry isn't just about visual signals. Some species use chemical mimicry. For instance, certain orchids mimic the pheromones of female bees to attract male bees for pollination. The males try to mate with the flower, and in the process, they pick up pollen and transfer it to other orchids. So, mimicry is a complex and diverse adaptation that can involve sight, smell, and even behavior. Any questions so far?