托福听力

🎧 听力原文

Listen to part of a lecture in a biology class. The professor is discussing the behavior of honeybees. "Now, we've talked about how honeybees communicate the location of food sources through a 'waggle dance.' But what's really fascinating is how this communication system adapts to environmental conditions. Recent studies have shown that when a food source is very close—say, within 50 meters of the hive—bees perform a round dance, which doesn't indicate direction. However, for farther sources, they use the waggle dance, where the angle of the dance relative to gravity conveys the direction of the food relative to the sun. Interestingly, the duration of the waggle phase correlates with distance—the longer the waggle, the farther the food. But here's a twist: in windy conditions, bees adjust their dance to be less precise, perhaps because the wind disperses scent cues, making precise directions less useful. Also, in urban environments, where food sources are scattered and small, bees tend to dance more frequently and for longer durations, possibly to recruit more foragers to less predictable patches. This flexibility suggests that the dance is not a fixed signal but a dynamic response to ecological demands."