Аудирование TOEFL

🎧 Транскрипт аудио

Narrator: Listen to part of a lecture in a biology class. Professor: Today we’re going to talk about a fascinating adaptation in the animal kingdom: camouflage. But not just any camouflage—we’ll focus on dynamic camouflage, where an animal can change its appearance rapidly to match its surroundings. The most famous example is the cephalopod, like the octopus and cuttlefish. These creatures have specialized skin cells called chromatophores that expand or contract to change color. But what’s really amazing is that they don’t just match the color; they also match the texture and pattern of their environment. For instance, a cuttlefish can make its skin rough and bumpy to mimic rocks, or smooth to mimic sand. This ability is controlled by the nervous system, allowing changes in milliseconds. Now, you might wonder, why is this speed important? Well, in the ocean, predators and prey are often in constant motion, so a slow change would be useless. The speed helps them avoid detection during quick escapes or ambushes. However, this comes at a cost—the neural processing required is intense, so these animals have large brains relative to their body size, which we’ll discuss next.