托福口语 Task 4

Today, we're going to talk about a fascinating concept in animal behavior called 'sensory exploitation.' This occurs when a species evolves a trait that takes advantage of an existing sensory bias in another species, often for reproductive success. The key point is that the trait isn't new—it's built on a pre-existing preference. Let me give you two examples. First, consider the male túngara frog. Females are naturally attracted to a certain 'whine' sound. Males add an extra 'chuck' to this whine, which exploits the female's auditory bias toward low-frequency sounds, making them more appealing. Second, think of the guppy fish. Female guppies have an innate preference for orange objects, likely because orange resembles ripe fruit in their environment. Male guppies evolved bright orange spots to exploit this bias, increasing their chances of mating. In both cases, the trait didn't create the preference; it simply amplified it.