托福口语 Task 4

Today we're going to talk about a concept in biology called 'mimicry'—specifically, when a harmless species evolves to look like a dangerous one to avoid predators. This is called Batesian mimicry. The key point is that mimicry works because predators learn to avoid the dangerous species, and then they also avoid the harmless look-alike. Let me give you two examples. First, consider the scarlet king snake, which is harmless, but it has red, yellow, and black bands very similar to the venomous coral snake. Birds that have had a bad experience with a coral snake will avoid any snake with that pattern, so the king snake benefits. Second, think about the hoverfly. It looks like a bee or wasp with its yellow and black stripes, but it has no sting. Predators like birds avoid eating them because they associate those colors with painful stings. So in both cases, the harmless species gains protection by resembling a dangerous one.