Northern elephant seals sleep in the deep to avoid predators - BBC

* Northern elephant seals sleep in the deep to avoid predators  BBC * Elephant seals enter 'sleep spiral' during deep ocean dives  CNN * Northern elephant seals can get less sleep than almost any other animal  NPR * You Won't Believe How Elephant Seals Sleep Underwater  Gizmodo * Seals Survive on Two Hours of Sleep. Why Can’t We?  The Atlantic * View Full Coverage on Google News
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