Did you know that when one of the biggest animals in the ocean sleeps, things look pretty odd?
Namely, recently, popular photos have appeared online and show sperm whales together, motionless and arranged vertically in the water.
These whales that are approximately the size of school buses, almost always seem like they’re ‘standing’ and clustered in pods of five or six when they’re resting.
Stephane Granzotto, a French photographer and filmmaker, caught this unusual behaviour while he was diving in the Mediterranean and documenting sperm whales for a photo book titled Cachalots.
The photo which was submitted to National Geographic Your Shot photography community shows the sperm whales who have been sleeping for an hour in a vertical posture, according to Granzotto.
Amazing: Sperm Whales Sleep Vertically
A study from 2008 published in the Current Biology journal documented this unusual sleeping position for the first time.
Sleep has also been observed in some captive cetaceans through monitoring of their eye movements; however, how whales rested was scarcely understood.
With data-collecting tags cupped to 59 sperm whales, the research team from the University of St Andrews and the University of Tokyo measured the period of inactivity in these animals.
It was concluded that the whales spent 7 percent of their days in this vertical sleeping posture near the water’s surface. They napped for 10 to 15 minutes.
The researchers pointed out at the time that they may be one of the least sleep-dependant animals in the world.
The Difference in Sleep between Captive Whales & those in the Wild
Interestingly, captive whales were found to use only 50 percent of their brain while sleeping which according to behaviour scientists, it’s a way to avoid predators, keep social contact, manage their breathing or keep swimming.
Scientists also observed a video taken in northern Chile which showed that the whales didn’t wake up from the napping on the surface until a ship that approached with the engines didn’t bump into them.
This notes that whales in the wild can enter a full sleep phase, unlike the captives.
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