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🎧 听力原文

Listen to part of a lecture in a biology class. Professor: Today we're going to talk about a fascinating example of animal adaptation: the bombardier beetle. This small insect, found on every continent except Antarctica, has developed an extraordinary defense mechanism. When threatened, it sprays a hot, noxious chemical spray from its abdomen. The spray can reach temperatures of up to 100 degrees Celsius, which is boiling point of water! The beetle produces this spray by mixing two chemicals, hydroquinone and hydrogen peroxide, in a special chamber. When these are combined with enzymes, a rapid chemical reaction occurs, releasing heat and creating a pressurized spray. The beetle can aim this spray with remarkable accuracy, even directing it towards the face of an attacker. This mechanism is so effective that it deters predators like ants, spiders, and even frogs. Interestingly, the beetle's body is perfectly insulated against the heat it produces, so it doesn't harm itself. This adaptation is a prime example of evolutionary engineering.