We can ask the same question the article poses initially about why we still sleep. Why hasn't this evolved yet? What are the disadvantages of this 'always-GCing' approach? In a best-case scenario, it might just be some sort of historical limitation that no longer applies* (just as our tendency to get fat is a result of an approach to resource conservation that made sense in the ancestral environment, where food was scarce and opportunities to feed intermittent, but does not in modern civilization, where food is nearly always available). In a less appealing scenario there might be some tradeoff that causes us to think less efficiently when this interstitial space expands.
[*] The extra fluids have to come from somewhere, which would mean they're not available for other tasks. Similarly, digestion is expensive--blood flows to the intestines after a meal, and if this is to happen then (since in the short term, you have a fixed amount of blood) it's less available for fueling your muscles. (And if you force yourself to be active right after a meal there's contention for these finite resources. Ever go for a run right after eating?)
Though perhaps there's less fluid involved here than there is with the intestines.
Still, why 8 hours of sleep instead of 2? The best explanation I've heard is famine resistance. Sleep conserves energy; until recently, humans were calorie-limited. Also, there's probably an advantage to remaining quiet and still in the dark, when human eyesight is at its worst and predators roam.
Also you can tell who hasn't had kids... without kids sleeping (and sleeping more than the parents) the older adults and teens in the tribe would go bonkers and be unable to accomplish anything. Best thing that ever happened to a newborn was sleeping alot so mom can get some food in her, etc. I guess as you get older you could ramp it down and maybe teens could simply stop sleeping, this is probably a secondary effect at most.
That's a bit too anthropocentric view. Also other animals sleep, even nocturnal animals.
And hunting being very important to the needs of certain homo sapiens sapiens populations would very much agree with your assessment. One advantage that we hold over primates is our ability to throw. Combine that with making spears and our ancestors quickly becoming apex predators makes sense.
Those are qualities of natural life that I find to be extremely well-engineered, and sadly lacking from most (all?) man-made engineering solutions.
Quick! What's 392 * 7374?
99.9% of people on the planet need pen and paper to figure out the answer. Our oh-so-adaptable brains can't seem to make a few neurons available for simple math. Heck, our brains can't store more than 7-9 items in working memory.
We're mostly unaware of our limitations because everyone else is similarly hobbled. But when we figure out a way to improve human minds, it will be a bigger game changer than anything that has come before.
I was responding to "Evolution is actually quite horrible at engineering. Since it can only hill-climb, we end up with ridiculous designs stuck in local maxima". In my opinion, several qualities of natural life compare favorably with man-made engineering (which is the only other type of engineering I can think of for the purpose of comparison), therefore I disagree that "evolution is actually quite horrible at engineering", at least without some kind of qualification.
I don't understand the purpose of your 1st or 4th paragraphs; I understand the 2nd and 3rd as saying something like "human brains are limited", but don't see how it connects to my response.
Could you clarify for me? Sorry that I didn't follow and thanks.
In fact you can pull up articles with a quick search about how people can attain pretty good mental math capabilities through training. It's hard work, but it's proof of the adaptability of the human mind.
I don't know I already thought the computer was the first "lever" for the mind that we've had. The computer has been pretty game changing for society, has it not?
Regardless, I'm not saying that there isn't a technique that would allow me to improve. I'm saying my inability has nothing to do with ubiquitous electronics.
No, we were never well equipped to do such computations, we didn't suddenly get worse at it with the invention of calculators. Consciously aware mental calculation is a very recent thing on an evolutionary time scale. I think even 10-20k years ago no one did any mental calculations beyond the most trivial arithmetic operations.
OTOH we have a pretty cool native physics engine in our brains and can solve pretty challenging problems such as predicting trajectories and modeling fluid flow. These skills were much more useful in our evolutionary past than arithmetic or algebra.
I suggest that the tendency to get fat is protecting us as a species on an evolutionary scale.
It's unwise to believe we could ditch that just because we haven't needed it for the last 2 generations or so: evolution cares little about a 2 generations scale.
Evolution has no foresight. Evolution can’t predict the future. Evolution is firmly rooted in the here and now. Doing something now (or not doing something now) because of a prediction of the future is something only humans can do, not evolution. Evolution knows no future.
In summary: variability in the gene pool is a form of future protection, and one that has been specifically selected for. Be careful before you shout "fallacy!"
Living humans don't have any reasonable concept of that, but evolution does have a memory of that.
I trust evolution to cover us for this type of future event better than I trust human prediction.
Being rooted in the here and now is something I would ascribe to humans before evolution: humans typically think as individuals on a time scale of 100 years - whereas if something has not been needed for 100 years, this does not illustrate that it is no longer of evolutionary importance.
 You can claim I am anthropomorphising here (but not in the earlier comment), but this is sometimes called an analogy, and is an accepted way of using the English language to describe concepts in a clear and simple way. Please ask any geneticist to translate this into evolutionary terminology if you remain unsure.
I'd take that a step further and say that evolution doesn't care at all!
The tendency to get fat isn't protecting us, it's just something that happened to be an attribute (randomly) of those of our ancestor who didn't die.
A number of animals can put one half of the brain to sleep while the other half remains alert¹.
As for eliminating sleep or shortening it; for such “trait” to evolve there would (beyond being physically possible and the proper mutations having occurred) need to be an advantage that would cause more individuals with the trait to survive (and pass on their genes).
Considering that we have been sleeping in trees and caves, and in groups, there’s probably not a significant larger chance of someone requiring less sleep to make it through the night.
Another possibility is that sleeping conserves resources, because we don't burn as many calories while asleep.
We shouldn't expect easy congitive enhancement through drugs unless there is a strong reason it wouldn't have been advantageous in the ancestral environment that doesn't matter now (e.g. much higher calorie usage).
Why should we expect an easy cure to syphilis in a drug if evolution has not found one? I don't know, but penicillin still works pretty darn well.
Even much enhanced, other senses don't provide even remotely as much information.
"the sleep researchers I spoke with agree that there’s no evidence that aided sleep is as effective as natural sleep."
Is there evidence that it isn't as effective as natural sleep? Why not say there's no evidence either way?
We know some stuff, like if you don't sleep, bad stuff happens to your body and you don't form memories effectively, but like the article says we haven't figured out why it's so essential.
Personally I agree. I'd also find it interesting to see how removing sleep from our lives would effect things like depression or even how it would just effect people having a bad day. For example if I'm having a terrible day I can't wait to get into bed, fall asleep and end it. The separation sleep provides between one day and another gives the feeling that tomorrow is a fresh start and the problems of today might be less. I'd guess I would be miserable for longer without sleep.
Real sleep deprivation is really 'funny', after having an allergic reaction to something in my home I couldn't sleep in it for 3 days, it's like being drunk with fever, you lose track of time, balance and get emotionally confused every 30 seconds.
ps: I wish they'd mention 20 minute long naps and how they can feel so "repleting" even though I don't believe a lot can be cleaned through the glympathic system.
But seriously, I've never noticed anything like that in my own practice. Granted I don't go for stretches longer than about 45 minutes, and I do it every morning when the cleaning has just happened. Or perhaps you'd need a specific additional technique apart from just sitting focusing on breathing. Visualisation techniques can sometimes dramatically change the effect of a meditation session (sometimes, but not consistently).
Additionally, I suggest trying to meditate when you're mildly sleep deprived. You'll find it harder to do, with yourself dozing off or blinking/blacking out occasionally. And while they're both, in some sense, mental states of "no thought", they are also worlds apart: the meditative state is a state of high focus, while the dozing/blinked state is pretty much the opposite.
What I've found in the few occasions I've experienced this (I don't like being sleep deprived so I try to avoid it :) ), is that you come out of such a blink-out state with a tiny bit of a jolt. Now, say I'd apply the same technique as one would use for basic meditation practice: when your thoughts wander away, try to observe that this has happened, congratulate yourself on noticing (instead of seeing it as failure) and gently bring your thoughts back to the focus.
Now I guess (and I'd have to try it out, but I don't want to because it involved sleep-depriving myself) one of two things will happen: One, over time (weeks/months), this process will train myself not to fall asleep, setting up circuits in my brain to keep me from dozing off (hopefully only when I don't want to). Of course the cleaning thing won't happen because you're awake and focused all the time, so you just got more efficient at sleep depriving yourself. OR number two, perhaps more likely, you'll doze off anyway, at some point. I can totally see that happen, dozing off into a half-dream where I dream I bring my mind back into focus and have this amazing meditation, suddenly get weird, in my dreams, and wake up a few hours later. It's the typical kind of trick my brain would pull on me.
Also, I don't quite see meditation like this. True, after 30 mins of meditating I am usually more relaxed and focused than I was before (but not always), but the main thing about meditation for me is just like sports and exercise: it's not so much about the immediate results, but it's training. When I meditate I do it because I am training my mind to keep focus and not drift off to everywhere except here & now, to have that state at least once a day, but to also take that habit onto the rest of the day when I'm not sitting. What you're describing sounds more like meditation as a kind of "pill" to give a direct effect, I find it's not very reliable in that sense, I use it more like training one's back muscles to give more support during the day.
"Sleep cleans your brain" or "Sleep garbage collection" or something. Still probably not good.
Off-topic: the new nytimes.com website feels a bit buggy on my iPad. None of the top banner button works (of the article page). Are they using JQuery-Mobile or similar slow js framework?