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Dolphins Can Sleep One-half of Their Brain At a Time Say Researchers
An anonymous reader writes "Looks like the evolution in multi-core computing is something nature has already figured out. Dolphins will sleep one core while the other remains vigilant, running background tasks necessary for survival. From the article: 'The scientists wrote: "From an anthropomorphic viewpoint, the ability of the dolphin to continuously monitor its environment for days without interruption seems extreme. However, the biological, sensory and cognitive ecology of these animals is relatively unique and demanding. If dolphins sleep like terrestrial animals, they might drown. If dolphins fail to maintain vigilance, they become susceptible to predation. As a result, the apparent 'extreme' capabilities these animals possess are likely to be quite normal, unspectacular, and necessary for survival from the dolphin's perspective."'"
This is known long ago... this is also an adaptation because dolphins breathing is not a reflex, so half the brain has to be always awake to remember breathing.
The news is that they can stay awake for 15 days at a time. Scientists have known for 30 years that dolphins can sleep with one hemisphere.
Republicans, hell. I'm a hippie, and most of my brain is asleep most of the... What were we talking about?
We've already found drugs that can keep a person going without sleep for weeks or months at a time, apparently without any significant reduction in cognitive ability or any significant change in neurological functioning.
Link please, otherwise I'm calling bogus. The official world record for going without sleep is 18 days.
Look up 'Fatal Familial Insomnia' in which death follows (as best as anyone can tell) from lack of sleep.
Memory consolidation , occurs more efficiently during sleep. That alone is worth it's evolutionary cost of sleep. Sure, Nature could have stumbled upon a memory consolidation scheme that do not involved sleep but it did not and evolutionary wise it seems that having a solid long term memory is more beneficial than not having to sleep. BTW if the drugs you talk about are orexin activator/recapture inhibitor/supressing enzyme inhibitor, only one: Orextin-A, is currently without know side effects. If those drugs you talked about do not act on the orexin transmitter up regulation, please tell me about them !
Jehovah be praised, Oracle was not selected
This is old "news". (Can we call it "olds"?)
Supposedly when you see a row of birds standing on a cable, all the ones in the middle are asleep, and the two on the end have half a brain awake so that their outside eye is paying attention.
More recent result is that even in humans, 'asleep' isn't a boolean proposition. Different parts of your brain may go to sleep at different times. Sometimes leads to "normal" sleepwalking, sometimes to horrid behavior because the impluse-suppression part is asleep and most of the rest isn't. See the overview article in a recent issue of Scientific American. (Current or previous issue, IIRC.)
Sheesh, evil *and* a jerk. -- Jade
That doesn't explain why Dolphins didn't just turn sleep off, since they are warm and active throughout all time. Was it just so fundamental to the brain architecture that the segmenting was needed, or is sleep providing something else that dolphins still need?
Evolution says the reason for sleep is that it improves a creature's ability to adapt... but what does sleep adapt us for?
Most creatures don't live long enough to have a need to adapt as an individual, but they adapt as a species over generations.
Humans probably have the greatest need to adapt as individuals. Every day:
You have to be able to adapt because society ensures that someone is constantly moving your cheese, and in return for this, you as an individual get to live longer than wild animals do.
One theory about why we need to sleep is that we need to filter out all the crap from the stuff we need to save. During REM sleep the neurons are subjected to spontaneous, chaotic activity, strengthening memories whose neuronal substrate is already sufficiently established, and disintegrating those that are weaker. Ever built a sandcastle by the water line at the beach? The walls that are not tightly packed get washed away when the water hits them, but the ones that are tightly packed survive and seem to actually be strengthened by the encounter. In a way, that's what REM sleep may do for our memories. Without that, it's all just an unstable jumble, and you can't adapt to all the crap in your life without the clarity to know what day it is or where the heck you're supposed to be.
I don't know what gay marriage, the FDA, mail-order girlfriends, and violations of space-time causality, and sandcastles by the beach have to do with the importance of sleep... but I can say with a fair degree of certainty that having read your post, you are a case study in what happens when someone doesn't get any. Please man, go to bed. The internet, such as it is, will not want for a missed opportunity for you to post to slashdot.
#fuckbeta #iamslashdot #dicemustdie
I'm pretty sure there's a joke in there somewhere.
Only a half brain operating? I know people who...
...drive like that.
...talk like that.
...code like that.
...make decisions at Microsoft like that.
...decide to buy Apple products like that.
and so on...