การฟัง TOEFL

🎧 บทถอดเสียง

Listen to part of a lecture in a biology class. Professor: Today we're going to talk about how some animals use camouflage not just to hide from predators but also to communicate. Take the cuttlefish, for example. These marine animals can change their skin color and texture in milliseconds. They do this using special cells called chromatophores, which expand or contract to reveal different pigments. But here's the interesting part: cuttlefish also use their color-changing ability to send signals to each other. For instance, a male cuttlefish might display a bold, striped pattern to warn off rival males, while it shows a mottled pattern on the side facing a female to court her. This is called dual signaling. So, camouflage isn't just about blending in; it's a sophisticated language. Now, researchers have found that cuttlefish can even adjust their signals based on the background to avoid being seen by predators while still communicating effectively. This suggests a level of awareness about their audience.