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16 weird sleep habits in the animal world

By: Angela Nelson on March 2, 2017, 11:50 a.m.
Sleeping sperm whales

Photo: YouTube

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Sperm whales

In 2008, a group of researchers were studying calls and behavior in sperm whales off the coast of Chile when they happened upon an amazing discovery: a pod of sperm whales sleeping so soundly in the water that none of them saw or heard the boat coming, even though whales are unihemispheric sleepers (half of the brain stays awake while the other half sleeps).The whales bobbed vertically in the water — some with their noses above water, some completely underwater — until the small boat accidentally bumped one of them, and then they all swam away, according to an account published in the journal Nature.

Based on this, researchers believe sperm whales do sleep fully while drifting for 10 to 15 minutes at a time, during which they don't breathe. Watch a Discovery Channel video of sleeping sperm whales below: