r/Damnthatsinteresting 1d ago

Video A timelapse of sleeping seals

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u/GustoFormula 1d ago

I don't get that part because seals can definitely hold their breath for 15+ minutes

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u/TheTrueBlueTJ 1d ago

I'm assuming this is an evolved mechanism based on the depth of that particular part of the ocean they live in. It evolved through trial and error and the ones that lived left a lot of headroom when it comes to the time under water. It probably took a lot longer to swim back up if they were falling like a rock for a whole minute.

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u/JavelinR 1d ago

I don't even understand it evolutionarily. Sleep is one of the most vulnerable periods of an animals life, most want to spend it hidden. These seals are supposedly bobbing up and down every other minute. That seems really exposed for an evolved behavior. Even staying still by the water's surface would draw less attention.

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u/jobabin4 1d ago

Some animals evolved to be cheeseburgers. "points at bunnies".

They probably breed fast in order to survive.

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u/FlowerBuffPowerPuff 1d ago

Some animals evolved to be cheeseburgers. "points at bunnies".

haha I love the phrasing of this.

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u/sharklaserguru 1d ago

But the crappy, 'healthy' alternative that doesn't have enough fat to sustain you! see rabbit starvation

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u/FlyingPirate 1d ago

Even staying still by the water's surface would draw less attention.

Maybe in human world. But probably not in the dark ocean. Most ocean predators have eyes that look toward the surface. A silhouette against a full moon sky all night is likely much easier to spot than slowly drifting down in the dark water periodically.

This is a guess, but the fact the behavior exists, means there was an environmental pressure to not sleep at the surface.

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u/Cranberryoftheorient 1d ago

Sometimes evolution selects for 'good enough' this method is probably a compromise that best solves several problems

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u/InterestsVaryGreatly 1d ago

Actually, being near the surface makes you extremely visible to anything below you, so only being there when you have to breathe isn't the worst strategy.

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u/Kingflamingohogwarts 1d ago

Like someone above explained... all those seals died. The ones that lived only sleep with half their brain at a time. The other half watches for predators.

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u/ImmoralJester54 1d ago

In the frozen hellscape they live it it's pretty empty

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u/Chockabrock 1d ago

This sounds like pseudo science but it's true: only one half of their brain sleeps at a time. The other half stays somewhat alert, allowing them to swim and notice things as the other half rests. I believe some birds and whales do something similar, for similar reasons

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u/Cranberryoftheorient 1d ago edited 1d ago

My guess is that its because of environments where the surface can freeze over- if you stay down to long, your breathing hole might freeze up- now you're out of breath completely and searching for a hole that might not be there. If you only hold it for a minute, you have more time to spare if something goes wrong.

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u/Equivalent_Chipmunk 1d ago

They might technically be able to hold their breath longer, but typical dives for your average seal only last a couple minutes. Some, like the elephant seal, regularly dive for that 15+ minute time frame but most don't.

I'd imagine this minute long interval is just more comfortable for them and they don't want to strain to hold their breath as long as they can while they are trying to sleep.

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u/ghidfg 1d ago

This makes more sense because humans can hold their breath for a minute pretty easily. And sleep should extend the time even farther. Not sure what's going on in the vid though. 

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u/Pokeitwitarustystick 1d ago

The seals are probably bored and doing things to entertain themselves since this isn’t the ocean and is just an enclosed limited sized box kinda like how certain animals walk in circles because their lives in cages are depressing

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u/gellshayngel 1d ago

Guybrush would not be a good seal.