Do fish sleep?

[gadazobe]

Do fish sleep with eyes closed? :what: Some of my corry's seem to sleep with their eyes closed and I wondered if they were ok or if it was sign of illness or something. Anyone got any ideas on that?

 

[gadazobe]

Fish don't have eyelids do they? :what: So how can corys close their eyes? I've been on the comp for too long - it must be affecting my brain

 

[Davy Reynolds]

:laugh: Ah well, put the red wine away
We've had some chats about fish sleeping b4 but never this.

 

[gadazobe]

It's Rose and her aliens - I MUST GET A TIN HAT :what:

 

[Macquatic]

:laugh: They're just winking at you gad. Mac.

 

[Feargal]

They're not sleeping...

They're communicating with their mothership. :laugh: :laugh:

 

[mrV]

Fish cannot sleep, because they can't close their eyes. Still, they are resting at night - swim on the bottom or somewhere where they think to be safety.

And that is the reason why you should use timer on lamps, so that day is regular - you know...

 

[reg2k2]

Sorry, I don't know about your cories, except I don't think it's sleep-related but I do think it's possible they close their eyes.

My pleco closes his eyes.  But he doesn't keep 'em shut.  He kinda flips them back.  I usually notice it if I've been staring at him a while.  Kinda like he's tryin' to see what the he** I'm lookin' at.  Then I get self-conscious---it is rude to stare, y'know.  
I was going to post a q whether anyone knew the reason and if it was voluntary or not, but this looks close enough to an eyelid topic. (I hope)  
I'd read an article years ago about it.  Not sure, I think it might be for protection; I think it's the same article that clued me in about some fish pecking at their eyes.  (I had a Kennyi that used to bug him, but I didn't know at the time it was the eyes.)  
   
BTW, do cories rest at night or day?

 

[Tropicalfishfn]

I think they do sleep my corys close there eyes and blink

 

[Dragonslair]

First of all gadazobe, do fish sleep? If the question is do fish sleep like us humans, for the reason of restoring our energies and sleep patterns, the answer would be no. Most fish never sleep, their metabolic rate slow right down and they will seem to rest, but the moment they stop moving the're dead. Fish need to transpire and respire and the only way they can do that is by passing water over their gills. It would be quite exhaustive for the fish if it has to open and close its mouth all the time,just to get enough oxygen through its gills. So it moves gently causing enough water turbulance and increase the amount of dissolved oxygen to pass. Fish do rest, particurarily if the temp. drops, their metabolic rate slows therefore shutting down the need for food and the use of needless waste of energy. This is also a danger period if you have a well planted tank with a lot of fish. During the night the reversal of photosynthesis occurs in plants, so instead of creating a well oxyganated water environment for your fish, at night the oxygen is extracted by the plants and carbon dixode is released as a by product. But this is a cycle and so again when daylight comes all is restored et seq.
As to Cories sleeping, well the reason these are popular fish is they are notorious "winkers". That is their main attraction. In studies they have a thin membrane over their eyeballs and like the action of a road catseye the corys clean their eyeball in much the same manner. Instead of a car tyre running over them to make they flick,as indeed they would if a car ran over them, a chemical stimulii within their optical apparatus triggers off the flicking movement which we percieve as a wink. Sometimes you can see their eyeballs following you independantly of the other, proving chemical eye response. We however love to intrepert human responses to creatures that just do things naturally.

 

[Rose]

It's Rose and her aliens - I MUST GET A TIN HAT!

You cant get a tin hat till they get you at least once. Don't know why but they won't give one to you till then. Once you have one you need to make sure it's a good tin hat. Otherwise they will keep abducting you. Oh and dont forget to keep it on other wise...well you get the point. I can't stop them they have minds of their own. Rose

 

[Alien Anna]

I don't know about fish, but there are quite a few animals (such as certain whales and prey animals) who can sleep with half their brain at a time.

Not being able to close the eyes is no indication - many animals have no eyelids, but still sleep in a similar way to humans. I would imagine, from observing their behaviour, that fish sleep but not with their whole brain - part of them is always awake and alert for danger.

Just FYI, humans asleep are not quite as unaware as you may assume - our ancestors would not have survived long if that were the case! We sleep unnaturally deeply in modern society.

 

[Rose]

It's those nights where you don't remember going to bed cuz your so exhauseted and sleep so deep you don't hear the alarm clock that I like. rose

 

[Dragonslair]

Actually we humans although we think that we have evolved so far, our basic instincts for survival are still embedded deep in our primitive brain. How many of you have heard your name being called out though a crowded room or particurarily women, have experienced a sixth sense. Or when you thought you were asleep and your child crys and you wake with a start. All this proves that your brain never sleeps. Through your auditory canals messages are constantly being received by your brain and your brain decides which is relevant to you in a particular circumstance. It will ignore traffic noises, and animal sounds outside the house because it does not perceive that to be a threat to you. It will however alert you if an unusual sound is heard entering your room that is unexpected. Even when you are asleep your brain is still processing information. It never sleeps in the way we understand sleep. This is a super complex subject and very fascinating.

 

[adeyc]

Well me. When I go to sleep you can drop a bomb outside, burn the place down etc and I wont wake up. but if somebody extra comes into the room I'm wide awake. eg at a recent party I fell asleep. two peeps left the room but three came back in, I was wide awake when the new person entered. strange aint it. done it all my life. I seem to know who's who in my sleep.