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  • How do dolphins sleep?

  • By covering their face with fins.

  • No.

  • Like humans, dolphins are mammals.

  • They breathe through lungs.

  • Hence, dolphins need to come up to the surface of water at regular intervals to breathe.

  • Also, dolphins have to protect themselves from dangerous predators.

  • Hence, they always need to be alert.

  • Just like security guards, right?

  • Just listen.

  • Each eye of a dolphin is directly connected to the opposite hemisphere of the brain.

  • Now, while sleeping, a dolphin shuts down one hemisphere and the opposite eye.

  • In the meantime, the other active hemisphere keeps track of internal bodily functions like breathing.

  • The open eye looks out for predators.

  • After 2 to 4 hours, the dolphin swaps the sleeping task.

  • It awakens the closed eye and resting hemisphere, and shuts down the active hemisphere and the open eye.

  • This type of sleep is called uni hemispheric slow wave sleep.

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B2 US hemisphere dolphin eye sleep shuts sleeping

How do dolphins sleep? | #aumsum

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    AumSum posted on 2019/04/16
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