托福口语 Task 4

Today, we're going to discuss a fascinating concept in animal behavior called 'sensory exploitation.' This is the idea that some animals evolve traits or behaviors that exploit the pre-existing sensory biases of other animals—usually to gain a reproductive advantage. Let me give you two examples. First, consider the male túngara frog. Females are naturally attracted to the 'whine' call of the male, but males that add a 'chuck' at the end are more successful. Why? Because the 'chuck' mimics the sound of a falling fruit, which triggers a startle response in the female's brain, making her more alert and thus more likely to approach. Second, think of the guppy. Male guppies have bright orange spots. Females are already drawn to orange because it signals food—ripe fruit. So, males with brighter spots exploit this food-related bias, getting more attention from females. In both cases, the males are not creating a new preference; they are tapping into an existing sensory bias.