The Unique , Sleeping Habits , of Whales.
'Newsweek' reports that whales, being aquatic mammals, require both sleep and oxygen in order to survive.
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It's an interesting dilemma for wholly aquatic air-breathers, Naomi Rose, Marine Mammal Scientist at the Animal Welfare Institute, via 'Newsweek'.
To deal with living in the water full-time, while having to breathe air at the surface, they have evolved into voluntary breathers, as a way to prevent accidentally inhaling water at inopportune moments, Naomi Rose, Marine Mammal Scientist at the Animal Welfare Institute, via 'Newsweek'.
Depending on the species, of which there are around 90 different kinds, whales can hold their breath for about an hour.
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However, 'Newsweek' reports, whales usually surface for air every 15 minutes.
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This means that whales sleep in a very different way than other mammals.
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Naomi Rose, Marine Mammal Scientist at the Animal Welfare Institute, explains that cetaceans, which include whales, dolphins and porpoises, would drown if they became fully unconscious.
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They continue to swim, slowly and regularly—in tight synchronous formation for social cetaceans—occasionally floating still for a few seconds, up to a couple of minutes, perhaps, often very near the surface, Naomi Rose, Marine Mammal Scientist at the Animal Welfare Institute, via 'Newsweek'.
Sperm whales hang in groups near the surface and enter relatively deeper sleep.
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Humpback whales have been observed resting on the surface for up to 30 minutes.
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Socially-complex killer whales sleep in tight-knit groups with other members of their pod.
