Do sharks sleep?

Question

my boyfriend told me sharks don't sleep is this true? He also said they never stop moving. This is pretty trippy I thought i'de come on here and ask u all coz I don't know weather to believe him. And how long do sharks live 4?

Answer 1

No sharks don't sleep. They don't stop moving either.

Answer 2

Sharks do sleep, although they have no eyelids so it may not appear as though they are.

The reason that (most) sharks never stop moving is because the forward motion pushes water through their gills allowing them to 'breathe'. If a shark were to become motionless, they would suffocate / drown. Although it should be noted that this is not the case for all species of shark.

Answer 3

It is unclear how sharks sleep. Some sharks can lie on the bottom while actively pumping water over their gills, but their eyes remain open and actively follow divers. When a shark is resting, they do not use their nares, but rather their spiracles. If a shark tried to use their nares while resting on the ocean floor, they would be sucking up sand rather than water. Many scientists believe this is one of the reasons sharks have spiracles. The spiny dogfish's spinal cord, rather than its brain, coordinates swimming, so it is possible for a spiny dogfish to continue to swim while sleeping. It is also possible that a shark can sleep with only parts of its brain in a manner similar to dolphins.

Answer 4

No, they don't. They must continue to move to have oxygenated water run past their gills... If they stopped moving, in essence they would suffocate from lack of oxygen.

As for their life span,we aren't sure, at least, not in nature. Ages even vary among the same critter that might exist in some other part of the world.... anywhere from 10-75 years seems to be the present thought, open to further research.....

The Monterrey Aquarium tried to display a Great White for awhile, and indeed they were successful.... they kept it fed so it wouldn't eat everything else in the tank... no one had ever displayed a Great White before, and they were tickled petunias!!!!!!!!!!! but as you guessed, it began to get huge, eating them out of house and home (so to speak) and also, creating real havoc in the aquarium. The decision was made to try to return it to the wild, and they did so successfully, even tho it had grown to many hundrends of pounds.... It was really a dicey job to get it out of their tank and back into the sea. See if you can find the DVD on the Discoverychannel.com listing... hugely interesting.

Answer 5

Your boyfriend is telling the truth. Sharks do not sleep and they never stop moving.

Answer 6

They do sleep but only one half of their brain goes to sleep at a time. So they are always aware of what is going on.

Answer 7

I read that they do sleep, but their bodies have a mechanism which puts them on "automatic" while they rest. If a danger arises or food appears, this sonar system wakes them up.

Also, their bodies do have to keep moving all the time or they would sink to the bottom. Isn't God creative?

Answer 8

Fish are known for swimming and eyes (Well, eyes for me)

Them staring at you is a bit freaky, but it seems they dont keep their eyelids down.

No, they dont sleep. Nor do they stop moving.

Answer 9

I doubt that very many fish sleep at all......they always have to be alert, for other predater's, you know....So , they wont get eaten by another fish..... they may sleep little cat-naps , here & there, is all. Most likely, you'd think anyway........

Answer 10

He's right.