托福口语 Task 4

Today, we're going to talk about a fascinating concept in biology called 'mimicry', specifically when harmless species evolve to look like dangerous ones. This is known as Batesian mimicry. The main point is that this adaptation helps the harmless species survive because predators learn to avoid the dangerous pattern and then mistakenly avoid the harmless look-alike too. Let me give you two examples. First, consider the scarlet king snake. It has bright red, yellow, and black bands, very similar to the venomous coral snake. Predators like birds have learned to avoid coral snakes because their bite is deadly. So when they see the king snake's similar pattern, they stay away, even though the king snake is completely harmless. Second, there's the hoverfly. This insect has black and yellow stripes like a wasp, and it even mimics the buzzing sound. Wasps sting, so predators like frogs quickly learn to avoid anything with those stripes. The hoverfly, however, has no stinger at all. But because it looks and sounds like a wasp, it gets the same protection. So in both cases, the harmless species uses mimicry to fool predators and increase its chances of survival.