Insomnia Mania: Newborn Mammals Don't Sleep for a Month

Study Says Mediterranean Dolphins Are Too Thin

Insomnia takes on a whole new meaning with the discovery that newborn dolphins and killer whales can forego sleep for their entire first month.

Hard to believe? Just ask their mothers.

The research finds both species of mammals can stay active 24/7 for weeks after birth. Mom gets minimal z's, too, as you might imagine.

Both mother and calf gradually get more shut-eye in subsequent months, researchers report in the June 30 issue of the journal Nature.

Don't try this at home

Such sleep deprivation would kill a rat or a fly, previous studies have found. Indeed, all other mammals whose sleep behavior has been studied snooze more at birth than in adulthood.

Humans doze a third of their lives away and can barely endure even with one night of bad sleep, suffering more auto accidents and less sex, among other downsides. The world record-holder for sleeplessness, Randy Gardner, stayed awake for 11 days straight in 1964. He hallucinated after four days, but held a coherent press conference at the end of the ordeal.

Scientists don't really know why getting 40 winks is so important for the average human. The answer likely involves the brain's need to recharge, as anyone who has pulled an all-nighter can attest after trying to concentrate the next day. Studies have shown that memory is consolidated and solidified during sleep.

Like cetaceans, human babies rob parents of sleep, of course. A comprehensive study in Australia concluded that the typical baby causes between 400 and 750 hours of lost sleep for Mom and Dad in the first year.

You snooze, you lose

For dolphins and killer whales, evolution apparently has determined that sleep must take a back seat to survival.

"Somehow these seafaring mammals have found a way to cope with sleep deprivation, facilitating rather than hindering a crucial phase of development for their offspring," said UCLA researcher Jerome Siegel.

There are advantages to being sleepless in the sea. Young cetaceans can better escape predators if alert, and their body temperatures stay higher as they wait for insulating blubber to accumulate. The lack of sleep also encourages rapid brain growth, the scientists say.

"Their bodies have found a way to cope, offering evidence that sleep isn't necessary for development and raising the question of whether humans and other mammals have untapped physiological potential for coping without sleep," Siegel said.

The study involved two adult female killer whales and their calves at Shamu Stadium at SeaWorld San Diego and four dolphins and their calves at a marine mammal center in Russia.

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Robert Roy Britt

Robert is an independent health and science journalist and writer based in Phoenix, Arizona. He is a former editor-in-chief of Live Science with over 20 years of experience as a reporter and editor. He has worked on websites such as and Tom's Guide, and is a contributor on Medium, covering how we age and how to optimize the mind and body through time. He has a journalism degree from Humboldt State University in California.