托福口语 Task 3

In biology, the concept of 'mimicry' refers to the evolutionary strategy where one organism (the mimic) evolves to resemble another organism (the model) to gain a survival advantage. This resemblance can be visual, auditory, or chemical, and often helps the mimic avoid predators by being mistaken for a more dangerous or unpalatable species. Mimicry is a form of adaptive evolution driven by natural selection, as individuals with better resemblance are more likely to survive and reproduce.

Professor: Let me give you a classic example from the rainforest. There's a harmless butterfly species called the viceroy, which looks almost identical to the monarch butterfly. Monarchs are toxic to birds because they eat milkweed, which contains cardiac glycosides. Birds have learned to avoid monarchs because eating one makes them sick. Now, the viceroy doesn't eat milkweed—it's actually safe for birds to eat. But over time, viceroys that happened to have wing patterns resembling monarchs were less likely to be attacked. Birds mistook them for the toxic monarchs and left them alone. So those viceroys survived and reproduced, passing on their monarch-like patterns to their offspring. Today, the viceroy’s appearance is a perfect copy—this is mimicry in action.