托福口语 Task 4

Today we're going to talk about a fascinating concept in animal behavior called 'biological rhythms'—specifically, how some animals have internal clocks that help them survive in changing environments. One key point is that these rhythms can be synchronized with external cues, like light or temperature, to optimize feeding and reproduction. Let me give you two examples. First, consider the fiddler crab. These crabs live on mudflats where tides rise and fall. Their internal clock is linked to the tidal cycle, so they become active right when the tide recedes, allowing them to scurry out to feed on algae without being swept away or exposed to predators like birds. Second, think about the honeybee. Bees have a circadian rhythm tied to the daily cycle of flower opening. They time their foraging trips to coincide with when their preferred flowers release nectar—usually in the morning—so they maximize energy gain and avoid wasting time when flowers are closed. So, in both cases, the animals' internal rhythms are fine-tuned to external patterns, which helps them survive more efficiently.