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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 ...

Animals have evolved to sleep in extreme ways — for example, taking micro naps during parenting, sleeping on the wing during ...

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 ...

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, ...

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 ...