How do Sharks Sleep? Some Rare Fascinating Facts!

How do Sharks Sleep Get the Fascinating Facts Here

Despite sharks’ fierce reputation, there is still much that is unknown about these creatures. One such feature is their sleep about which scientists are still not sure; however, presenting their theories to make some sense of it. Let’s find out how sharks sleep.

Shark’s Physiology

To comprehend how sharks sleep, one must first comprehend their physiology. Sharks are cold-blooded, which means their body temperature is controlled by the water around them. This is significant because it helps them to store energy and swim for extended periods of time without tiring. Sharks also have a distinct circulatory system that allows them to provide significant amounts of oxygen to their muscles while swimming at fast speeds.

The Different Types of Shark Sleep

Shark sleep is classified into two types: unihemispheric slow-wave sleep and bihemispheric slow-wave sleep.

Unihemispheric slow-wave sleep refers to the sleeping method in which one half of the brain sleeps and the other half is awake. This helps the shark to be attentive and receptive to its surroundings even while sleeping.

Bihemispheric slow-wave sleep occurs when both parts of the brain are asleep. This form of slumber is more typical in larger sharks who are less likely to be preyed upon.

How Do Sharks Remain Alert While Sleeping?

One of the most remarkable aspects of shark sleep is that sharks can remain attentive and receptive to their surroundings even while sleeping. Because of their unihemispheric slow-wave sleep, this is conceivable. This permits the shark to continue swimming and responding to its surroundings even while asleep.

Sharks are also able to stay awake while napping due to their unique circulatory system. Sharks have a unique circulatory system, allowing them to provide significant amounts of oxygen to their muscles even while asleep. This enables them to swim at fast speeds while being vigilant to prospective prey.

How Do Sharks Wake Up?

Sharks do not have the same sleep-wake cycle as humans. Instead, they can wake up instantly if necessary. It is primarily because of their sleeping methods and unique circulatory system, which does not let them sleep completely, but keeps their brain activity alive.


Through research, it has been found that sharks have two main types of sleep, unihemispheric slow-wave sleep and bihemispheric slow-wave sleep, which allows them to remain alert and responsive to their environment while they are sleeping. Additionally, they have the unique ability to wake up suddenly, keeping them safe from predatory attacks.

About the author

Yumna Ahmad

An experienced content writer, photographer, and avid reader amazed by the sea world and its creatures. I am lettin people become fascinated with the ocean planet through my writings.