No, whales do not sleep like humans. While humans typically experience bilateral sleep where both hemispheres of the brain are in a deep sleep state simultaneously, whales have a unique adaptation for sleeping.
How Whales Sleep
Instead of falling completely unconscious like humans, whales utilize a fascinating adaptation known as unihemispheric sleep. This means that to be able to sleep, whales shut down half of their brain at a time.
The Purpose of Unihemispheric Sleep
This unique sleeping method serves critical functions for a marine mammal:
- Breathing: Unlike humans, whales must consciously surface to breathe. By keeping half of their brain awake, they can continue this essential function even while resting.
- Awareness: Remaining partially awake allows them to be aware of their surroundings, helping them detect potential threats from predators or navigate effectively.
- Maintaining Position: Whales will usually stay in place as they sleep near the surface, or sometimes swim slowly, actions facilitated by keeping one side of the body active.
This contrasts sharply with human sleep, which involves a state of deep unconsciousness and paralysis during certain stages, making it incompatible with the survival needs of an aquatic mammal that must actively breathe.
Whales Sleep
