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For the first time, scientists have recorded brain activity in a free-ranging, wild marine mammal, revealing the sleep habits of elephant seals during the months they spend at sea. The new findings, ...

Elephant seals sleep about 10 hours a day on the beach, but during months-long foraging trips at sea they average just 2 hours of sleep per day. These 2-month-old northern elephant seals are sleeping ...

WASHINGTON (Reuters) - Sleep is a precious commodity for people and across the animal kingdom, indispensable even as its biological purpose remains somewhat mysterious. We spend about a third of our ...

When you weigh more than 10,000 pounds, you need a lot of food just to survive. All those hours spent searching for grasses, roots and fruits means there's little time left over for sleep. How little?

Northern elephant seals might be masters of multitasking in the animal kingdom because they’ve learned how to sleep and dive at the same time — all while avoiding predators. The elephant seals can ...

CNN — Northern elephant seals might be masters of multitasking in the animal kingdom because they've learned how to sleep and dive at the same time — all while avoiding predators. The elephant seals ...