How do whales manage to sleep without drowning, given that they must consciously breathe air? 既然鯨魚必須有意識地呼吸空氣，它們是如何做到在不溺水的情況下睡覺的？
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They exhibit unihemispheric slow-wave sleep, allowing one half of the brain to rest while the other stays awake. 他們表現出單半球慢波睡眠，讓大腦的一半休息，而另一半保持清醒 Correct! Whales shut down one hemisphere of their brain at a time (keeping one eye open) so they can continue surfacing to breathe and watch for threats. 鯨魚一次只讓大腦的一個半球進入睡眠狀態（保持一隻眼睛睜開），這樣它們就能繼續浮出水面呼吸並警戒威脅