Dolphins Can Sleep One-half of Their Brain At a Time Say Researchers 139
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."'"
why is this new? (Score:4, Insightful)
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.
Re:Wrong headline (Score:5, Insightful)
Re:Evolution (Score:5, Insightful)
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?
Re:So do birds. (Score:4, Insightful)
And anyone who thinks that the brain is inherently capable of only doing one thing has never driven long-distance.
Has *anybody* never had that experience where you are driving along thinking and then suddenly realise you've just navigated the past 20 miles, through traffic, round corners, through junctions, with gear-changes, etc. without remembering doing so?
Your brain is more than capable of doing those tasks - and alerting you to problems just as quickly as when you're concentrating on the task - in the background without you knowing. (What scares me most about them is not the fact that it happens, but that I assume I stopped at red lights, followed traffic signs, didn't ram someone off the road, etc. and have to quickly recall events that I seem to have taken no conscious part in!)
I've also had the (strange) privilege of knowing someone with multiple-personality-syndrome. This is extremely similar - one personality is at the fore but the others are there, in the background, observing events and doing things, just out of mind at that moment. In fact, in MPS, it's just a more pronounced version triggered by certain psychological problems (lots of abuse cases, lots of a very particular type of psychiatric therapy that seems to "trigger" MPS in vulnerable individuals - and is STILL practised in the one part of America where most MPS cases come from!).
Your brain is not a single thing. It's a collection of billions of things, each with their own job. They group and work together but they also can separate off (otherwise you would have to "think" about how to move your arm rather than just passing it off to a group of brain cells that do that all day long) and even divide your consciousness in two in perfectly ordinary people with no mental health issues.
And, like others have said, have you never had that thing late at night where you wake up because of an odd (and quiet) sound despite the fact that every other night you slept like a baby. How do you think that works? The brain is always awake, in some fashion, it's just a matter of whether it decides something is a threat or not (otherwise every predator would just wait until your were asleep because you'd be an easy target), and then "presses the emergency button" to get the rest operational very quickly.
The dolphin thing is well-known. And any idiot with a cat knows that it doesn't really "sleep" for 18 hours a day, it's always aware and very, very rarely in an actual complete sleep (for the first time in 12 years, I manage to "scare" my cat the other day because it was completely, 100% asleep and didn't hear me come in, didn't feel me approach, until I stroked its fur - I actually thought it was dead, it was so deep in sleep).
And every driver will tell you that they have driven on a kind of "automatic pilot" including some of the most complex observation, judgement, quick-reaction and motor skills that the average person will perform in a day, while they were thinking about what to have for dinner.
Humans are animals. Animals have brains. Brains are a collection of groups of cells that, by their very nature, are inherently malleable, ever-changing and independent. It's no shock that dolphins can do this. What's more interesting is that humans seem to have lost the ability/need to do this so much.