托福口语 Task 4

Today, we're going to talk about a fascinating concept in biology called 'mimicry'. Mimicry occurs when one species evolves to resemble another species, often to gain a survival advantage. There are two main types: defensive mimicry and aggressive mimicry. Let me give you two examples. First, consider the monarch butterfly. It is toxic to birds because it feeds on milkweed, which contains toxins. Birds learn to avoid it. Now, the viceroy butterfly, which is not toxic, has evolved to look almost identical to the monarch. This is defensive mimicry—the viceroy gains protection because birds mistakenly avoid it, thinking it's poisonous. Second, consider the anglerfish. This deep-sea fish has a fleshy growth on its head that glows and wiggles like a small fish. When a hungry predator approaches to eat the 'bait', the anglerfish quickly captures it. This is aggressive mimicry, where the mimicry helps the predator lure its prey. So, in both cases, mimicry is a powerful evolutionary adaptation that enhances survival.