托福口语 Task 4

Today, we're going to talk about a fascinating concept in animal behavior called 'sensory exploitation.' This is when a species evolves a trait that takes advantage of an existing sensory bias in another species, often for mating or survival. The key point is that these traits aren't random—they're shaped by what the receiver already finds attractive or stimulating. Let me give you two examples. First, consider the water mite. Male water mites perform a specific swimming pattern that mimics the vibrations of a tiny prey animal. Female water mites are naturally attracted to these vibrations because they indicate food. So, when the male does this dance, the female approaches, and he mates with her—her sensory bias for prey vibrations is 'exploited.' Second, look at the túngara frog. Male frogs produce a 'whine-chuck' call. The 'chuck' part is particularly attractive to females because it resembles the sound of a nearby predator, which triggers a startle response that makes females more alert and receptive—again, exploiting an existing sensory bias for danger. So, both examples show how evolution can hijack pre-existing sensory systems for reproductive success.