2006-12-18 17:50:55 · 9 answers · asked by Anonymous in Pets ➔ Fish
Sleep is a shutting down of the external senses,distractions, to the brain. Sleep is a recuperative process, allowing the body to recover from the stresses of the day to day living we all do. All living things need something, a time to recerate, and we call that period sleep for anything other than active life as we know it. Plants go dormant, but not in exactly the same manner as mammals do. So, the eyelid is a key element. Fish do not have eyelids. They do not need them. An eyelid is there to moisten the surface of the eye to keep the cells of the eye alive. In water, fish are always in a moist environment, so no eyelid was necessary to keep the surface cells of the eye moist. But, they still need the sleep cycle as we all do, so they sleep with eyes open, but the sleep cycle desensitizes the input from the eyes to the brain, so they sleep with eyes open. A part of their brain STILL is aware of what the eyes see so they can respond to a predator if it is in view. I wish I could do the same, be aware of a predator even when I am asleep.
2006-12-18 18:14:54 · answer #1 · answered by rowlfe 7 · 2⤊ 0⤋
Most fish spend time in an energy-saving state that we call resting or sleeping. Although this is probably different than the way most land animals sleep. Fish will often lay at the bottom of the tank and not move, sometimes you can sneak up and watch them during this time. They can't close their eyes because they have no eyelids to do so.
There is still too little research on this to know what is going on when there in a energy-saving state though.
2006-12-18 21:45:45 · answer #2 · answered by awana 5 · 0⤊ 0⤋
they don't favor eyelids, and instead can sleep at the same time as its darkish out. it extremely is why they say as an example off your aqauriam lights at evening. otherwise, your fish received't sleep real. this can positioned stress on them and cause them to more beneficial in all likelihood to strengthen particular diseases.
2016-11-27 19:30:43 · answer #3 · answered by ? 4 · 0⤊ 0⤋
They have on Eye lids.
Light is filtered so much that it is very dark under water.
2006-12-18 17:55:00 · answer #4 · answered by minootoo 7 · 0⤊ 1⤋
See god created them for a special purpose....... that to in water they always have danger so they didnt got eye lids similar to man......... it is good chance for them to escape........... understood ......... !
2006-12-18 18:04:36 · answer #5 · answered by Shaik Moinuddin 2 · 0⤊ 0⤋
They dont have eyelids....no reason for them to have eyelids.
2006-12-18 17:52:13 · answer #6 · answered by Anonymous · 0⤊ 0⤋
Because they have no eyelids.
2006-12-18 17:52:10 · answer #7 · answered by joycedomingo 3 · 1⤊ 0⤋
im afraid not as im not a fish.
2006-12-18 18:12:09 · answer #8 · answered by Anonymous · 0⤊ 0⤋
They don't have eyelids.
2006-12-18 17:52:16 · answer #9 · answered by CO_Hiker 3 · 0⤊ 0⤋