How Do Constantly Swimming Sharks Ever Rest? Scientists Just Figured It Out:
Marine biologists have discovered that sharks 'surf' ocean currents in a conveyor belt configuration, allowing them to take turns resting.
[...] These sharks never stop swimming for their entire lives. They need to keep moving in order to extract enough oxygen with their gills to keep them alive, so stationary resting, like the way other animals rest, is out of the question.
Exactly how sharks rest was a bit of a puzzle, until on a dive during the day, Papastamatiou noticed that the sharks were swimming against the updraft current in a certain channel. Even more interestingly, they were remarkably still, barely moving their fins or tails.
[...] As they crept forward to the front of the channel, the lead sharks would slip backwards, letting the current carry them back to the starting position. It was like some sort of strange conveyor belt – the sharks would inch forward against the current, be carried back, then inch forward again.
Journal Reference:
Yannis P. Papastamatiou, Gil Iosilevskii, Valentina Di Santo, et al. Sharks surf the slope: Current updrafts reduce energy expenditure for aggregating marine predators, Journal of Animal Ecology (DOI: 10.1111/1365-2656.13536)
(Score: 4, Funny) by Anonymous Coward on Sunday June 20 2021, @11:53AM
No it isn't... they just dim the laser.
(Score: 0) by Anonymous Coward on Sunday June 20 2021, @12:02PM
shark jump you!
(Score: 2) by ealbers on Sunday June 20 2021, @12:10PM
Isn't this the same question?
How do constantly breathing humans ever rest? Its just part of the thing which keeps them alive...those who do breed, those who do not do not.
(Score: 2) by hendrikboom on Sunday June 20 2021, @01:21PM (6 children)
Hard to see how swimming against a water current is any less effortful than swimming at the same relative speed in stationary water.
(Score: 2) by Rosco P. Coltrane on Sunday June 20 2021, @03:42PM (5 children)
I think the point is that sharks gather together and the ones at the front do most of the job of overcoming the drag against the flow of water for the guys behind, who need less energy to keep moving - thereby "resting" in their definition of resting - and they take turn at the front. Kind of like geese flying in a V formation, cyclists in a peloton, or even penguins taking turn sitting on the outside of the pack and shielding all the other from the cold.
I guess the bit about swimming against a current and staying stationary is orthogonal to the energy conservation technique. Perhaps they like the view where they rest, or they pick a particular location where the neighbors aren't too noisy or something.
(Score: 2) by acid andy on Sunday June 20 2021, @04:37PM
I assumed that staying stationary allows their brains to go to sleep so they don't have to plan where to navigate to next or end up getting lost or swimming somewhere dangerous.
It reminds me of swifts (the birds) that can sleep during flight.
If a cat has kittens, does a rat have rittens, a bat bittens and a mat mittens?
(Score: 2) by MIRV888 on Sunday June 20 2021, @11:34PM
I think they would expend minimal effort and get maximum water flow through their gills. The idea is not to fight the current but let it do the breathing.
or it could be lasers.
(Score: 0) by Anonymous Coward on Sunday June 20 2021, @11:53PM (1 child)
It's called drifting and I'm not sure why this is new ... it's been known ... heck, even swimmers do it?
(Score: 0) by Anonymous Coward on Sunday June 20 2021, @11:55PM
err ... drafting *
(Score: 2) by hendrikboom on Monday June 21 2021, @03:10PM
That makes sense.