托福口语 Task 4

Today we're going to talk about a fascinating adaptation in the animal kingdom: mimicry. Specifically, I want to focus on how some harmless animals mimic dangerous ones to survive. This is called Batesian mimicry. The key point is that by resembling a species that predators avoid, the mimic gains protection without actually being harmful. 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 learn to avoid the coral snake's colors, so they also avoid the king snake, even though the king snake is harmless. Second, there's the hoverfly. It looks like a bee, with yellow and black stripes. Birds avoid bees because of their stings, so they also avoid hoverflies. However, hoverflies have no stinger at all. In both cases, the mimic's survival depends on the predator's learned fear of the dangerous model.