托福口语 Task 4

Today, we're going to talk about a fascinating concept in biology called 'mimicry.' Specifically, I want to focus on how some harmless species have evolved to imitate dangerous ones for survival. This is known as Batesian mimicry. The main point is that by resembling a toxic or harmful species, a harmless species can gain protection from predators who have learned to avoid the dangerous look. 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 avoid the coral snake because of its deadly bite, and they also avoid the king snake, mistaking it for the dangerous one. Second, there's the hoverfly. It has black and yellow stripes just like a wasp, but it has no stinger. Birds that have had a painful experience with wasps will avoid hoverflies as well, even though they are completely harmless. So in both cases, the harmless species benefits by mimicking a dangerous model.