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, ...

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The surprisingly short shut-eye may be a way for the elephant seal to avoid predators—an intriguing find from the first-ever sleep study on marine mammals in the wild. A baby northern elephant seal ...

Elephant seals drift downwards into the ocean in a "sleep spiral" to catch up on sleep while on months-long foraging trips but are programmed not to drown, according to a new study. The seals fall ...

During the many months they spend at sea gorging on fish and squid, the massive mammals sleep only about two hours a day. By Annie Roth It long seemed as though African elephants were the champions of ...