Dolphins do sleep, but they are not easy to be found when they sleep. Because they are aquatic mammals, when many people observe dolphins, they find that they swim in the water all day long, so most people think that they will not rest. But in fact, dolphins also sleep. It's just that they sleep in a special way. Dolphins rest alternately with their left and right brains, so that they can keep abreast of their surroundings and avoid accidents or attacks.

Generally, dolphins close one eye when they rest. At this time, they can still keep swimming. When one side of their brain rests, they will open it, then close the other eye and rest again. Of course, if dolphins are in an environment that they think is very safe, they will stop moving and float in the water to rest.

In principle, dolphins do not need to hibernate, because they are warm-blooded animals and their body temperature is constant, so they will not hibernate under normal circumstances. In addition, dolphins live in the deep sea, and the temperature fluctuation in the deep sea will not be too great, so even in winter, it will not have much impact on their normal life. In addition, dolphins will have enough food after winter, so they don't need hibernation to preserve their physical strength.