托福口语 Task 4

Today we're going to talk about a fascinating behavior in the animal kingdom called 'mimicry for defense.' Many animals use mimicry not to attract prey, but to avoid being eaten. The main point is that some species evolve to imitate dangerous or unpalatable creatures, which gives them a survival advantage. Let me give you two examples. First, consider the scarlet king snake, which is harmless, but it has bright bands of red, yellow, and black, very similar to the deadly coral snake. Predators that have learned to avoid coral snakes also avoid the king snake, even though it's completely safe. This is called Batesian mimicry. Second, there's the viceroy butterfly. For years, scientists thought it was a Batesian mimic of the monarch butterfly, which is toxic to birds. However, recent research shows that viceroys are actually distasteful to birds themselves. So, both monarchs and viceroys are unpalatable, and they resemble each other. This mutual resemblance, called Müllerian mimicry, reinforces the lesson for predators: both species benefit because a bird that tastes one will avoid both. So, you see, mimicry can work in different ways, but the outcome is the same: increased survival.