Why has nothing evolved to not need sleep?

[Cuddles]

I see what your saying, but the argument that an animal after sleep performs better is not really answering the question. The problem here is that evolution should have selected for an animal that didn't sleep yet still performed. There is not one animal in the world that seems to have taken this path. So, since this has not happened, there seem only a few reasons 1) oops 2) it's not actually more beneficial to survival 3) sleep is above and more important to life that evolutionary processes.

My vote goes with 3). And it would be real interesting to find out why this is, but I dont think anyone really knows for sure.

This doesn't even begin to make sense. Sleep more important than evolution? It may interest you to know that apples are not oranges, and attemptint to compare the two will rarely lead you to a logical conclusion.

 

[Ichneumonwasp]

I always hate these discussions. Everything here is necessarily speculation.

Keep in mind that the reason a behavior evolves may not be the same thing that behavior is used for currently.

Might it not be the case that sleep initially served one purpose -- keeping fish and amphibians from being eaten at certain times (forced quiescence is preferable to behavioral quiescence if the animals haven't much of a frontal lobe to begin with) -- but was the means by which, as BenBurch has suggested, higher levels of cognition were even possible. Nature always takes advantage of what is at hand -- possibly complex neural activity could not have evolved in the first place if sleep were not already there for another purpose?

I point this out because REM sleep seems to have a particular purpose now related to washing away the dreck of the day, but I seriously doubt if that were its original purpose -- the primary purpose seemingly being some form of thermoregulation early in phylogeny.

 

[sol invictus]

It seems (to me anyway) that sleep comes first, and evolutionary processes evolve around this, for the reasons I gave above. If evolution came before and was more important than sleep, sleeping should have been selected against as species evolved to confer the advantgaes of retaining an awake state.

Does that make sense even to you? What are you talking about, "sleep comes first"?

 

[Furi]

Maybe the shut down during sleep is also to allow for a form of pain relief from compressed spines, Sore Paws, Lactic acid build ups, Impact bruising, Fluid deposition, and also the rest to allow greater amounts of blood for other organs other than the muscles for repair and other biochemical operations, as well as giving the brain time to clear it's buffers and run a defrag.

You mentioned above that in a herd all members need to be aware, WHY?

within a social structure, not all members have to be sleeping at the same time, you can have some providing cover for those to rest during inneficient periods for hunting and gathering, I dunno they migh Moo or Bray, Oink, bark or some other communication method to raise any dangers.

I (and approx 8.5% of the population) am colourblind, I also have above average night vision (not all CDV results in greater night vision), I can perform an awful lot better in Lowlight / moonlight / near darkess than most normal people can in these conditions as I do not depend predominantly on colour for visual enviroment interpretation and seem to have greater resolving power, So I (and others with the same advantage) could be classed as an evolutionary safeguard, security guards pulling the night shift so that others get to sleep soundly in their chosen habitats and digest and conserve energy to go out and gather food for the group, the other advantage is that no-one ever asks us to go out and pick fruit . evolutionary symbiosis, we get a good periods rest during the nice warmer daytime so we can pull the night shift protecting the rest from all the Ghoulies and Ghosties and things that go bump in the night, for the gatherers and hunters to go out and get food for us (shift allowance for having to pull the doom stag)

The problem here is that evolution should have selected for an animal that didn't sleep yet still performed. There is not one animal in the world that seems to have taken this path. So, since this has not happened, there seem only a few reasons 1) oops 2) it's not actually more beneficial to survival 3) sleep is above and more important to life that evolutionary processes.

Should? I didn't realise evolution had to head to every concievable goal and come up with a viable stable system for that engineered goal, merely what is expediant.

Option 1, err what do you mean by "Oops" are you indicating that someone forgot to include it, or "Oops" Evolution doesn't do what I want it to Damnit! I know I am defining sleep to a degree that applies to animals that are relatively modern and have currently evolved where they require sleep, I know that I am asserting that it would be beneficial to survival, so why hasn't it happened, is it a problem with my comprehension or the question itself, or "oops" HA therefor there is no such thing as evolutin I got you Bow down before my creator (see oops someone forgot to put it in there)

option 2, Or maybe there has already been a high order animal that could get by without REM sleep and it got killed off already because it was a hinderance to survival compared to animals that enjoyed sleepytime, or possibly evolution is heading towards your specified goal and it may take a little while yet, or maybe sleep is as efficient as it needs to be within the current non 24 hour constant illuminated biosphere.

Option 3, WTF Sleep is more important to life than the evolutionary process, hmm do you mean that sleep is beneficial to animals and that is why we have evolved to sleep, Evolution is not change for changes sake, "Congratulations! You manage to get by with < 2 hours sleep out of 24, Advance to Evolve and collect 200 genetic improvements at your next propagation"

 

[Ichneumonwasp]

Is there any actual evidence that a sleeping animal in a den is more vulnerable to attack than one resting but awake in a den? My intuition tells me different from the OP -- that sleep provides more protection.

Or, as Mark Twain would have it, from "Eve's diary":

"Very well, then, what have you to say?"
"That there is something better than logic."
"Indeed? What is it?"
"Fact."

 

[Zeuzzz]

This doesn't even begin to make sense. Sleep more important than evolution? It may interest you to know that apples are not oranges, and attemptint to compare the two will rarely lead you to a logical conclusion.

I agree with that. 'Importance' isn't exactly a scientifically well defined term. So I shouldn't have worded it like that.

I mean that (and I'm not sure about this myself I need to give it more thought) evolution does an incredible job of refining animals to the best of their ability, but nothing has evolved to gain the advantages of being awake and alert all the time. Which, in a very general sense, means that sleep is more important, or rather that evolution seems incapable of reducing sleep and enabling animlas to experience the benefits of sleep without the periodic lack of/decrease in awareness of environmental stimuli that every animal on the planet experiences.

 

[Zeuzzz]

Is there any actual evidence that a sleeping animal in a den is more vulnerable to attack than one resting but awake in a den? My intuition tells me different from the OP -- that sleep provides more protection.

No, sleep itself is a disadvantage as the animals have a decrease in awareness of environmental stimuli. However, your correct in the sense that the methods animals employ to enable themselves to be safe when they sleep can be advantageous.

 

[godless dave]

I see what your saying, but the argument that an animal after sleep performs better is not really answering the question. The problem here is that evolution should have selected for an animal that didn't sleep yet still performed. There is not one animal in the world that seems to have taken this path.

You've already been told that whales and dolphins don't sleep.

 

[Zeuzzz]

Maybe the shut down during sleep is also to allow for a form of pain relief from compressed spines, Sore Paws, Lactic acid build ups, Impact bruising, Fluid deposition, and also the rest to allow greater amounts of blood for other organs other than the muscles for repair and other biochemical operations, as well as giving the brain time to clear it's buffers and run a defrag.

Totally agree, they are all valid possibilities. So an animal that has evolved to do all these things in an awake and alert state would be at a huge advantage to those that have to shut themselves down to perform these actions. But this has not happened.

You mentioned above that in a herd all members need to be aware, WHY?

I didn't say that, they dont! If you were a predator, would you prefer to pick a herd that where most the animals were sleeping and not aware of your presense, or a herd that was all awake and could see you coming?

The awake herd wins every time.

Should? I didn't realise evolution had to head to every concievable goal and come up with a viable stable system for that engineered goal, merely what is expediant.

At the risk of repeating myself, An organism cannot choose to evolve in a certain direction, or to acquire a particular trait. It doesn't matter how wonderful it might be, if a mutation that would permit it has never occurred, it can't happen.

However, as has been speculated above, it's possible that such a mutation HAS occurred, and turned out to NOT be adaptive, in which case it quickly disappeared from the gene pool again.

But why this wouldn't happen is the interesting question.

Option 1, err what do you mean by "Oops" are you indicating that someone forgot to include it, or "Oops" Evolution doesn't do what I want it to Damnit! I know I am defining sleep to a degree that applies to animals that are relatively modern and have currently evolved where they require sleep, I know that I am asserting that it would be beneficial to survival, so why hasn't it happened, is it a problem with my comprehension or the question itself, or "oops" HA therefor there is no such thing as evolutin I got you Bow down before my creator (see oops someone forgot to put it in there)

Why does everyone always presume questions about evolution are from creationists? I find this reaction most odd. I just meant by 'oops' that evolution has not yet given this advantage to any animal, and there appears to be no substantiative reason why no animal could perform the job sleep is thought to do while remaining alert and awake.

Option 3, WTF Sleep is more important to life than the evolutionary process

It seems so. Evolution has not been able to encroach on sleep in any animal, for whatever reason.

 

[Zeuzzz]

You've already been told that whales and dolphins don't sleep.

It depends on your definition of what sleep is, which is why I tried to define it for this discussion in an earlier post.

They do sleep, its just slightly different from mammalian sleep. All animals sleep. They especially all show the train in number 1) of the following list, which is the aspect of sleep I am talking about, and dont see the necessity of.

THE EVOLUTION OF SLEEP

Sleep is:
a) a lack of/decrease in awareness of environmental stimuli
b) the maintenance of core body temperature (in homeotherms)
c) relatively easily reversible (to wakefulness)
d) has distinct EEG patterns (different from wake)
e) has spontaneous occurrences with an endogenous periodicity
(independent of other bodily needs and environmental cues)[.....]

Fish and Amphibians show periods of activity and inactivity, cyclic show less response to environmental stimuli in “quiet” times, but are not unresponsive…so maybe are just “resting” EEG data scare, but does not look much different from wake

 

[Reality Check]

It depends on your definition of what sleep is, which is why I tried to define it for this discussion in an earlier post.

They do sleep, its just slightly different from mammalian sleep. All animals sleep. They especially all show the train in number 1) of the following list, which is the aspect of sleep I am talking about, and dont see the necessity of.

THE EVOLUTION OF SLEEP

Do bacteria sleep? What about viruses?
If sleep is so important then why it is restricted to animals with neural processing? It is more likely that having a brain is really important for some reason and that having to sleep is just a minor disadvantage.
Thanks BenBurch for pointing this out.

 

[Zeuzzz]

I think the best answer in this thread was by the guy that simply told the truth.

An animal that does not sleep would be at a huge advantage over all other animals as animals are more vulnerable when asleep. Animals go through all the hassle of digging a burrow, or climbing a tree so they are safe when they sleep.

So why have none evolved to counter this large disadvantage and perform the jobs that sleep does while in an awake state?

An excellent question.

We currently don't know exactly why animals need to sleep. We can measure that it is detrimental to them if they are hindered in sleeping, but why this is the case, we don't know.

There are many potential possibilities. But out of the ones mentioned here so far, I dont see that any of them hold up to scrutiny.

And I find it hard to see how we can ever know the answer to this definitively. Its related to all the unanswered questions about consciousness and how we experience what we experience, and why. That annoying question philosophers ask to scientists, 'why'. Is the universe how we consciously perceive it, or if we are receiving a radically altered version of events as our mind interprets the information our brain (supposedly) receives. The last century has worked wonders in unravelling the mystery of the body and brain, the next century is going to be about the nature of the mind and altered states of consciousness, like sleep. Sleep is unreal, our everyday experience is real, people on psychedelics are deluded, NDE's are tricks of the brain, lucid dreaming is co-incidence, meditating is useless, all positions are very hard to prove either way, and I think we are nearly at a point where we can start addressing some of the gaps in our explanatory knowledge of how the brain mechanistically works vs how it produces these subjective states of feeling and consciousness. People like to say that science has nearly uncovered everything we know about the universe, that we just need to collect that one more bit of data, tweak a tiny aspect of a theory, and our picture will nearly be complete, soon we will know nearly everything, even the true origin and destiny of the universe. Our current understanding is correct and based on loads of data so can't be disproven type attitude, the closed minded unhealthily skeptical approach. That’s bo**ocks. Anyone who says that is severely deluded, just as deluded as people that put their faith in religion. The history of science tells us something quite different. Who knows what surprises and mysteries are waiting around the corner. Science is cool.


Christ, I need to go back to decaff. Dont choose physics and philosophy at uni, very bad combination.

 

[Ichneumonwasp]

No, sleep itself is a disadvantage as the animals have a decrease in awareness of environmental stimuli. However, your correct in the sense that the methods animals employ to enable themselves to be safe when they sleep can be advantageous.

You keep saying that but supply no evidence. I think the opposite is true because it keeps them out of trouble when they are at a natural disadvantage. I think there are many underlying reasons for sleep, but the selective advantage of keeping animals necessarily quiet during a time when their visual systems are not adapted is probably enough of an answer. It clearly does not explain many features of sleep -- like why the rebound phenomenon. That is probably explained by sleep's restorative powers for complex neural systems.

 

[Polgara]

Christ, I need to go back to decaff. Dont choose physics and philosophy at uni, very bad combination.

Lose the philosophy, keep the physics. :O) Trust me. heh.

 

[Zeuzzz]

You keep saying that but supply no evidence. I think the opposite is true because it keeps them out of trouble when they are at a natural disadvantage.

But the question is why they have to be at this natural disadvantage in the first place.

The evidence is so obvious I dont need to explain it. Maybe my OP wasn't clear enough in defining the aspect of sleep I am talking about, sleep can mean many things depending on which aspect your referring to. How can I put it in a way that wont be confusing. An animal that is not aware of environmental stimuli can not gain an advantage over things that are an environmental stimuli as they will not be consciously aware of the environmental stimuli stimulating them

Choose an animal that gains an advantage by decreasing their awareness of environmental stimuli, and state what this advantage is. It should be an advantage gained from the actual decrease in awareness of surroundings, not another unrelated advantageous aspect of sleep, or method employed to sleep.

I think there are many underlying reasons for sleep, but the selective advantage of keeping animals necessarily quiet during a time when their visual systems are not adapted is probably enough of an answer.

I dont think it does. Even at night when an animals visual systems may not be as good as it is at night, they still gain no advantage by becoming not aware of their surroundings at night, they may not hear, smell or sense any predator. Or any predator may not sense any prey passing by they could eat and gain an advantage this way.

Owls can see perfectly well in the day and night, and can hunt in either. They choose to be nocturnal, not because they can't hunt in the day, because they have the inherent disadvantage that all animals share in that they have become not aware of their surroundings (for some unknown reason) to sleep. So they choose to hunt at night, because they can generally get more food at this time. Still, sleeping in the day is not an advantage for the owl. So I dont think this resolves the issue either.

 

[Ivor the Engineer]

Evolution generally finds local optima, not global. Often once an successful solution to a problem with multiple variables is found it is not possible to optimise one particular variable without incurring a greater cost from a less-good solution for all the others.

Effectively we and many other organisms are stuck with needing sleep. It's not great, but it's not bad either.

It works.

 

[godless dave]

There are no advantages to being oblivious to environmental stimuli. There are advantages to having a central nervous system. Central nervous systems seem to need sleep to function propertly. That's the whole answer.

 

[paximperium]

I do so enjoy a discussion thread that goes around in circles...and then makes a left turn into a figure of 8...

 

[Ichneumonwasp]

But the question is why they have to be at this natural disadvantage in the first place.

The evidence is so obvious I dont need to explain it. Maybe my OP wasn't clear enough in defining the aspect of sleep I am talking about, sleep can mean many things depending on which aspect your referring to. How can I put it in a way that wont be confusing. An animal that is not aware of environmental stimuli can not gain an advantage over things that are an environmental stimuli as they will not be consciously aware of the environmental stimuli stimulating them

Choose an animal that gains an advantage by decreasing their awareness of environmental stimuli, and state what this advantage is. It should be an advantage gained from the actual decrease in awareness of surroundings, not another unrelated advantageous aspect of sleep, or method employed to sleep.

The advantage would be keeping from them reacting to stimuli at a time when they are at a distinct disadvantage. The situation is in animals that have not yet developed the frontal lobes to inhibit their responses. Opossums may play dead because they have the neural machinery to do so. Animals with much less neural machinery just can't do that; it makes sense to inhibit their responses in certain situations and 'turning them off' is a fairly easy and economical solution (certainly much more economical than developing a huge nervous system to inhibit responses). Once the solution of sleep is hit upon, providing the advantage of decreasing animal activity when it is not appropriate, that solution can be used for other purposes -- memory incorporation, etc. One of the supreme advantages may have been to allow neural development beyond the stage of a few integrated ganglia, since sleep appears to be absolutely necessary for most animals and probably for all larger neural networks. The cetecea are a great example since they must sleep, but do so only one hemisphere at a time. They do not need to be kept fully asleep, but they clearly need sleep.

As with most issues in evolution, there is the issue of why the behavior developed in the first place and how it is used in beings later in phylogeny.

I dont think it does. Even at night when an animals visual systems may not be as good as it is at night, they still gain no advantage by becoming not aware of their surroundings at night, they may not hear, smell or sense any predator. Or any predator may not sense any prey passing by they could eat and gain an advantage this way.

Owls can see perfectly well in the day and night, and can hunt in either. They choose to be nocturnal, not because they can't hunt in the day, because they have the inherent disadvantage that all animals share in that they have become not aware of their surroundings (for some unknown reason) to sleep. So they choose to hunt at night, because they can generally get more food at this time. Still, sleeping in the day is not an advantage for the owl. So I dont think this resolves the issue either.

But owls are much further down the evolutionary 'path' than the animals in which sleep originally developed. You can't look for the original reason for sleep in higher mammals necessarily. That is the whole reason why I mentioned the REM story. We don't have good evidence for REM sleep in reptiles, but there are forms of it in birds and mammals. The mammals with the most REM sleep, as I recall, are the echidna -- early forms, since they are monotremes. REM is probably not particularly important for sifting through info in that group, but it does seem to play a role in thermoregulation. While all speculation, this may be the primary reason that REM originally developed, but may have nothing to do with why we have REM sleep.

 

[Wowbagger]

I'm telling y'all: It is NOT the evolution of sleep we need to ask about. Sleep is the default position of life forms, and one that life forms will always try to revert to, as much as it can get away with. It is waking life that evolved: How we are able to become more aware of our surroundings, for some period of time, is the question to ask.

It might be wrong to assume staying awake all the time would be perfect evolution. What if sleeping all the time actually is, from nature's point of view?

Perhaps animals won't evolve to "not need sleep", simply because nature prefers them to sleep as much as possible, and only remain awake for what is necessary to survive.