托福口语 Task 4

Today we're going to talk about a fascinating behavior in the animal kingdom called 'mimicry.' Now, mimicry is when one species evolves to look or act like another species, often to gain a survival advantage. The key point is that mimicry isn't random; it's a strategic adaptation that helps animals avoid predators or catch prey. Let me give you two examples. First, the monarch butterfly. Monarchs are toxic to birds because they eat milkweed, which contains toxins. Birds learn to avoid them after a bad experience. Now, the viceroy butterfly, which is not toxic, has evolved to look almost identical to the monarch. Because birds mistake viceroys for monarchs, they leave them alone. This is called Batesian mimicry, where a harmless species mimics a dangerous one. My second example is from the ocean: the cleaner wrasse. This small fish sets up 'cleaning stations' where larger fish come to have parasites removed. Now, there's a fish called the saber-toothed blenny that mimics the cleaner wrasse's appearance and swimming pattern. But instead of cleaning, it bites a chunk of flesh from the larger fish and darts away. This is aggressive mimicry, where the mimic lures its victim by pretending to be harmless. So, in both cases, mimicry serves a clear survival purpose.