托福口语 Task 4

Today, we're going to talk about a fascinating concept in biology called 'mimicry.' Now, mimicry is when one species evolves to look or behave like another species, often to gain a survival advantage. There are two main types we'll focus on: Batesian mimicry and Mullerian mimicry. Let me give you an example for each. First, Batesian mimicry: This is when a harmless species mimics a dangerous or toxic one. For instance, the scarlet king snake, which is non-venomous, has red, yellow, and black bands that closely resemble the venomous coral snake. Predators avoid the king snake because they mistake it for the dangerous coral snake. Second, Mullerian mimicry: This occurs when two or more harmful species evolve to look alike, reinforcing each other's warning signals. A classic example is the viceroy butterfly and the monarch butterfly. Both are toxic to birds, and because they share similar orange and black patterns, predators learn to avoid them more quickly after just one bad experience with either species. So, in summary, mimicry can either be a free ride on another's warning or a shared advertisement of danger.