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 look or behave like another species to gain an advantage. There are two main types: Batesian mimicry and Mullerian mimicry. In Batesian mimicry, a harmless species imitates a dangerous or unpalatable one to fool predators. For example, the scarlet king snake has red, yellow, and black bands similar to the venomous coral snake. Birds avoid the king snake because they mistake it for the coral snake, even though the king snake is harmless. In contrast, Mullerian mimicry occurs when two or more harmful species evolve to look alike. This is beneficial because predators learn to avoid them more quickly. A classic example is the monarch and viceroy butterflies—both are distasteful to birds. By sharing the same orange-and-black pattern, they reinforce the lesson in predators' memory. So, while Batesian mimicry involves a harmless species copying a harmful one, Mullerian mimicry involves multiple harmful species converging on the same warning signal.