托福口语 Task 4

Today we're going to talk about a fascinating concept in biology called 'mimicry'. Mimicry is when one species evolves to look or behave like another species, often to gain a survival advantage. There are two main types of mimicry: Batesian and Müllerian. Let me give you an example of each. In Batesian mimicry, a harmless species mimics a dangerous one to avoid predators. For instance, the scarlet king snake, which is non-venomous, has similar red, yellow, and black bands as the deadly coral snake. Predators learn to avoid the coral snake's warning colors, and so they also avoid the harmless king snake. In contrast, Müllerian mimicry occurs when two or more harmful species evolve to look alike, reinforcing the warning signal. A great example is the monarch and viceroy butterflies. Both are toxic to birds, and by resembling each other, they share the cost of educating predators. Birds that eat one and get sick will avoid both species, benefiting each population. So, mimicry is a powerful evolutionary strategy that can either deceive or cooperate among species.