Northern elephant seals sleep just two hours a day at sea
The mammals snooze less than 20 minutes at a time during dives
![A photo of a northern elephant seal poking its head out of the water.](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2023/04/041923_MT_nappingseals_feat.jpg?fit=1030%2C580&ssl=1)
Northern elephant seals are deep sleepers. Literally. They dive hundreds of meters below the ocean surface to take naps unbothered by sharks or killer whales.
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