托福口语 Task 4

Today, we're going to talk about a fascinating concept in biology called 'mimicry', where one species evolves to resemble another for survival. There are two main types: Batesian mimicry and Müllerian mimicry. Let me give you some examples. First, consider the harmless scarlet king snake. It has bright red, yellow, and black bands, very similar to the venomous coral snake. Predators learn to avoid the coral snake's colors, and the king snake, being harmless, benefits from this false warning—it's Batesian mimicry. Now, for Müllerian mimicry, think of two species of poisonous butterflies, the monarch and the viceroy. Actually, viceroys are also toxic, and both species share similar orange and black patterns. By looking alike, they share the cost of teaching predators—each predator that eats one learns to avoid both, so the mortality is spread across both species. So, the professor's main point is that mimicry is a survival strategy, but the mechanism and evolutionary implications differ between the two types.