Dolphins are extremely intelligent creatures. They can “talk”, learn, play and even heal people with their presence. But they have another unique ability that amazes even scientists: dolphins can sleep … without letting their guard down! How is this possible?
First, it’s important to realize that dolphins are not fish. They do not have gills and breathe with their lungs like humans. That means they need to come to the surface regularly to breathe air. If a dolphin fell asleep the way we do – completely shutting down and no longer controlling its breathing – it could have ended tragically. But God came up with an ingenious solution!
Half-brain sleep – that’s how it works
In dolphins, the halves of the brain sleep alternately. While one hemisphere of the brain is resting, the other remains active: it controls breathing, hearing, the environment and swimming. After a while, they “switch places” and the other hemisphere rests.
This state is called unigemispheric sleep. Thanks to it, the dolphin never completely loses control of its body and breathing. It continues to move, sometimes swimming slowly or even remaining motionless on the surface, but it always has one vigilant part of the brain that monitors safety.
Why is it also safety for the pack?
Dolphins are social animals. They live in groups and take care of each other. This way of sleeping allows them to stay alert, avoid predators, and even take care of babies. Adult dolphins take turns to “stay awake together” – there is always someone who can hear and see what is going on around them.
And newborn dolphin babies don ‘t sleep at all for the first few weeks after birth! Their mom doesn’t get a full night’s sleep either – she swims nearby, pushing the baby to the surface to breathe. This is exhausting, but necessary for survival.
You can sleep, but wisely
Dolphins don’t sleep like we do – with a complete shutdown. They “snooze” alternately with each half of their brain to keep breathing and stay alert. This is an example of how in nature there is a perfect balance between rest and survival. And yet another proof that dolphins are true geniuses of the ocean.
