The Evolution Of Sleep

It gets dark anyways, so you might as well just wait for when you can see. Being able to shut down while you're waiting and avoiding unnecessarily spending energy would be beneficial and so would the rebuilding aspects. Pretty much every animal sleeps in some way, so it’s been important since early on. Fish and reptiles have a more primitive sleep state than birds and mammals. And even invertebrates have a shutdown mode. But I don’t think non-animals sleep. I guess that as you get more complex systems within organisms, the more they need to regulate them. I doubt it from our current state, but I suppose it would have been possible. Although, the energy input would have to be a lot higher so that might be preventative. Don’t forget that predator-prey relationships have to form a balance, or the preds will eat all their food, so the vulnerability thing would kind of work itself out. Well this is all just me speculating.

Well, it could be... If the circadian rhythm was already a part of their evolution before they got to the poles/caves. If we're going back that far, I'd prolly bet that sleep evolved independently between Protostomes and Deuterostomes. Protosomes splits into antropods, flat worms, and mollusks (etc) while Dueterostomes splits into urchins, round worms and vertebrates (etc). I think that there's some disparity between the sleep that these two groups exhibit, so that could suggests its unrelated. I don't know, but there's also a lot of "rebuilding" that goes on during sleep, which would still count as 'activity' even though its helping. Its still gonna require energy, but you're not doing all that other activity as well. If you didn't sleep, then you'd have to be rebuilding while you're doing your normal activities, and then all that together would require that much more energy. Adaptations to sleep that arrise after sleep has already evolved isn't gonna help us much in figuring out how sleep evolved in the beginning. To contrast: How much energy does a brown bear save during its hybernation? That's not really what I was thinking... Preds that took too much advantage of sleeping prey wouldn't have survived, so we'd just be left with the ones that didn't. I see it as more of a balancing act than an arms race. With aliens, having their own circadian rhythm, the sky's the limit...But sleep seems like a good idea to me. Everything degrades and nothing can run forever, it just makes sense to take a break every so often. Would you prefer to never have to sleep but then just have a lifespan that was 30% shorter? Would you sleep more for a longer life?

If they evolved to their places after sleep had already evolved, it could still... but yeah, I doubt the circadian rhythm is the entire explanation. Energy regulation should be a big factor too. But fish do have a more primitive form of sleep. I'm still not seeing what's so bizarre about it? Seems like a good idea to me... Well, my computer does have a sleep mode (although nothing really happens during it). Don't most of the droids in Sci-Fi have it too? Is there any reason to think that we wouldn't? Nothing runs forever and everything wears down, so it makes sense to delay the inevitable with a sleep mode. Wouldn't they? You said it right there, even with an ultimate result of escalation, the whole thing is kept in blance through graduality. If having a sleep state means having to spend less energy, then that benefit could be the selective pressure away from an arms race to sleeplessness. I suppose they could, but then, what kind of energy input is that going to require? How much would you need if you had to do all your repair work while you were running at full speed? Would that be sustainable? So instead of sleeping at night, you just have to be eating the whole time? Would that really be better? Shit, now I got to get another job to pay for all this extra food I need, or I could just shut down instead. Would you want an engine that you never had to turn off but that you had to change the oil in on your way to work? Is your question why the oil doesn't just work longer? Or why there's no perfect engine?

Why do you find it so odd?Anything besides the pred-prey relationship? Life evolved on a planet that was dark half the time... Sounds like the creationist musings on why evolution didn't give us eagle vision...There's lots of "issues" like that because you only have to evolve to be good enough.

But you're burning those calories for a repairing process, just think how much you'd be burning if you were repairing while you were still active.I do agree that the total unconsciousness aspect of it is a bit weird. As grazers they have a pretty-much-constant input of energy.Compared to the carnivores, who only eat so often and therefore need a lot more sleep.The python is cold blooded so that just adds a whole nuther element...From Message 48: And if you mess with the computer screen, then the content of this forum appears to change... but does it? Heh, I think you meant that the mind is a product of the brain, but I still don't think the evidence is all that conclusive.