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 resemble another species, often for protection. There are two main types: Batesian mimicry and Mullerian mimicry. Let me give you an example of each. First, consider the harmless king snake. It has bright red, yellow, and black bands, which closely resemble the venomous coral snake. Predators that have learned to avoid the coral snake also avoid the king snake, giving the king snake protection without being poisonous itself. This is Batesian mimicry, where a harmless species mimics a dangerous one. Second, think about different species of stinging bees and wasps. They often share similar black-and-yellow warning coloration. Because predators learn to avoid this pattern after a painful encounter with any one of them, all the species benefit—each reinforces the warning to predators. This is Mullerian mimicry, where multiple dangerous species mimic each other. So, the key difference is that in Batesian mimicry, only the model is dangerous, while in Mullerian mimicry, all the mimics are dangerous.