disclaimer #1: I'm dumb

Was thinking the other day what an incredible waste of time sleep is. 1/3 of our life spent with our eyes closed, laying in bed.

Then I began wondering - in millions of years of evolution, why hasn't our need for sleep diminished (or maybe it has and i just don't know)? Why haven't we begun to whittle that down?

Would it make sense that the more 'evolved' humans become, the less their need for such a massive time drain would be/

I think the most likely probable answer is that I am not properly understanding evolution, so thought I'd ask.

Probably it has to do with how brain stores information and processes it.... For neurons (synapses) to form it takes time and energy

animals that sleep the lest are far more likely to be on the pray side and also have a basic brain with no adaptivity

My dig sleeps 22 hours a day if he could. Case closed. I haven't slept in 3 days. Evolution baby

There is variation in amount of sleep required. Do you observe that those who sleep less reproduce more?

Definitely beyond my scope of knowledge.

There are legends of massively productive (not necessarily re-productive) people who slept significantly less than the average person - Da Vinci -2 hours a night; Thomas Jefferson - 2 hours; Edison - 5 hours; Isaac Newton 3-4 hours; Ben Franklin 2-4; etc.

That of course raises lots of questions - would those people be so consumed with 'work' that reproducing is lower on their priority scale? Would those people, due to their accomplishments and status be 'desirable' and thus have more opportunities for reproduction than the 'average' sleeper? I have no clue.

I would hazard a guess that most people suffering from insomnia are among the lowest current sleepers in modern society. I would also guess that those folks generally aren't walking around with a fully functioning mind and thus - are not as desirable - and do not reproduce (or produce) as much as a normal citizen.

(I suppose all of this ignores the most obvious question - is "amount of sleep required" genetic?)

Noway regarding less hours sleep more work or quality. Sleep is superimportant! Sleep is the key reason we have succeeded.

Sleep has such great role to so many areas of the human body even immune system. I am/feel superintelligent (super eager to solve problems and compose ideas etc) after a very long back to back (jet lag style) session of sleep 6+6 h basically with a break in between lasting several minutes after depriving myself a bit the prior day or 2 (exactly as an intercontinental flight would lead to). It is a unique feeling of saturation that clears your mind and make it able to tolerate unreal stress of complexity in thinking and calculations. Massive surge in optimism too. So clearly it has to do with effects in brain chemistry.

Read why its important;

http://en.wikipedia.org/wiki/Sleep

Maybe it is to out benefit that we sleep and not the opposite. Stupid overworking in modern times isnt exactly leading to quality of life or great ideas now is it???

About Newton or Da Vinci please offer links of that fact because i am not buying it. 2 h of sleep may lead in a few days to a 6+6 pattern like i described that maybe Da Vinci was experimenting with by depriving self for a couple days with 3-4-5 hours and then the 3rd or 4th day doing the long back to back sleep to emerge the next day as super boosted and creative. You have a serious breakdown if you go many days at 2-3 hours only.

I have caught myself taking notes in lectures at grad school after long sleepless nights due to extreme homework assignments the next day in class that i couldnt even understand what i was writing later! WTH!!! Its miserable and if you try to drive or do something important you can essentially kill yourself and others. Do not experiment with sleep and sensitive jobs at the same time the deprivation takes place. Its suicidal.

I think you have evolution confused with cocaine

I think you're right but it doesn't seem implausible that its possible to have all the benefits without sleep, for example if and when we develop full human strength AI its not obvious that it would have to sleep.

Of course not, AI is not biological probably so sleep wont be needed and the brain has special benefits from sleep but also heart and other organs. The immune system is very interesting too with sleep playing a role. (that wiki link is very good actually). My point is that sleep is contributing to the system, its not a waste , its not just rest, its a lot more than that , its opportunity for other function to take place. We need it for more than the simplistic sense of being tired and afterward feeling rested. Its vitally important for more systems even muscles and bones.

The fact is that from a mechanical point of view human brain and body in general is amazing given that it lasts so many decades in pretty great condition. Even a great computer or an old car will fail after a few years/decades (havent had a cpu loss however since elementary school, all else fails cpu never did.)

So my point is we need to see sleep as something other than rest/relaxation. Maybe if we could arrange for these functions to be fulfilled differently one day we might be able to reduce sleep to a 50%.

However the fact no major animals have shown to not sleep might imply that there is no evolutionary benefit in reducing it (although clearly there ought to be one if seen in a naive sense of time saved) maybe possibly because the role it plays is so much vital to so many systems that no single benefit from the saved time can decouple the system from all the other benefits it requires and sleep provides.

Not just the role it plays in terms of stuff done while asleep but it also allows optimisation for day or night rather than both which might be a highly fit solution.

I can go with sleeping only 3 hours, I've done this for a month straight and continue to do it once in awhile. I haven't done it this summer but I believe that most people just limit their self because they don't have discipline.

I do believe that the brain is at a more rapid state with lack of sleep and you become slightly delusional time to time. (since that is how I usually feel when sleeping only 3 hours)

Anyway I'm only a college student that can fool around with how he lives but I'm sure there are people that are forced to live with sleeping few hours.

This post pretty much wins the thread, but yeah...humans (and pretty much ALL vertebrates) need sleep, or time in some state that we would call "sleep." Theories exist as to why, but there isn't much good evidence to support any of these theories afaik.

How do you know this is true? Maybe it happened once in a while if they were inspired or consumed by something. I doubt however that this was their norm.

Some other things to think about:

1. When you are sleeping your metabolism goes way down. Probably evolutionary advantageous when resources are scarce.

2. For humans that rely so heavily on sight and have a high cone/rod ratio (meaning poor night vision) probably evolutionarily advantageous to be hiding in a cave at night being quiet than stumbling around in the dark with lions and tigers that can see much better than you.

-So basically, sleeping might be advantageous because when you are sleeping the chance of you doing something stupid to get yourself killed goes way down.

I wonder if way way back it was all just to conserve, but then that time started being used for memory sort, body repair etc and now that we don't need to conserve energy and resources were stuck since a bunch of processes have come to depend on it.

Assuming losing the need to sleep doesn't increase total waking hours of life, I'd rather keep sleeping. I'd sleep 20 hours/day if it meant I could live 4x farther into the future.