Comprensión auditiva TOEFL

🎧 Transcripción de audio

Listen to part of a lecture in a biology class. The professor is discussing animal communication. Professor: Today we're going to talk about how animals communicate, and specifically, we'll focus on the concept of signals. A signal is any behavior or feature that conveys information between individuals. One classic example is the waggle dance of honeybees. When a worker bee discovers a rich source of nectar, she returns to the hive and performs a dance that indicates the direction and distance of the food. The dance is not just a random movement; it's highly structured. For instance, the angle of the dance relative to the vertical axis of the hive represents the angle of the food source relative to the sun. And the duration of the waggle run correlates with the distance. Now, you might think this is a simple stimulus-response, but research shows that the dance also depends on the quality of the food. If the nectar is of high sugar concentration, the bee dances more vigorously, which encourages other bees to go out and forage. However, there is a cost. Performing the dance takes time and energy, and it also makes the bee more conspicuous, potentially attracting predators. So, bees seem to balance the benefits of sharing information against the risks.