so why sleep?

Earlier I thought it was because of the earth's rotation, and day-night cycle. But then I realized, the very first animals evolved in the deep oceans where sunlight was devoid.

What then could the reason be?

Actually at this point of time its very difficult to theorize because we don't have a proper scientific understanding of how sleep happens to other species on earth. When we sleep we become immobile. We don't have a sense of touch or any normal audio that is going on around us. Its as if our brain shuts down its vital functioning.

We know what lack of sleep can do to us. It can cause disorientation, make us less-responsive to normal auditory stimuli, and, many other cognitive problems. These patterns of problems can be observed on other species too. There are species of fruit flies which were subjected to experiments which disrupted their normal "rest cycle". It was found that fruit files which did sleep were able to locate food faster, whereas those that didn't get enough sleep couldn't find it fast enough.

There is an evidence that sleep is necessary for proper development of the body as well as the brain. The brain tries to repair connections or even make new ones after it "shuts down". So I suppose this is why infants spend most of the time sleeping.

But how can we explain it in terms of evolution and natural selection?

I suppose the answer to that can be formulated as follows:

Growth or development in any life form is a natural process. But I suppose a "rest phase" is necessary here, because that ensures a healthy development. Any life form in its normal growth or development, if it does not have a "rest phase", its doomed to fail and will be less capable of surviving long enough. And being awake does need more energy, and more maintenance.

So now you can bring natural selection into the solution. So those species which took to this pattern of growth and development survived and flourished.

You may very well ask, there are animals that don't have brains; do they require sleep?

This is almost like suggesting that the brain is the organ responsible for sleep. If so why don't our brains go to sleep keeping all other functions working as necessary? I can't imagine how a human would be in such a condition. But the general understanding should be, if the brain "rests" so does the body. One or the other organs need functioning, others don't. For e.g. our muscles don't need to move so much so they are relaxed.

To a degree this is a kind of symbiosis. This kind of a symbiosis is necessary for healthy living and also to minimize energy consumption.

I really have quoted articles I've read, or videos I've seen on the subject. Research in sleep is still in a study and observe phase. Scientists have not extensively studies "sleep" in other species like they have done on their own species.

However, often I do come across articles and they will be tied to this blog post, as and when I come across some interesting articles. You can find a list of artefacts tied to this article below:

http://bitly.com/bundles/deostroll/x

You can keep track of interesting stuff over at my google+ page. Please follow that page if you want regular updates. If you do have questions yourself, just drop in an email to ask [dot] deostroll [at] gmail [dot] com. You can also post a question directly at quora.com and let me know about it. Would be happy to answer or review answers.

The explosive past...

David Attenborough's documentaries are “visionary”. The inspiration behind writing this post comes from one of his documentary series called the Origins of Life. It kind of attempts to explain some of the common features almost all the animal species have. Most of these features stare at our faces; I mean, we experience them everyday. But we are not there to appreciate it...we just let it pass like an average ordinary day.

But this post is not about the average ordinary day either...Scientists, when they study fossils, theorize with the little evidence they get. They try to imagine how that particular species would have lived. Why they had the body plan that they had. What kind of advantage did that body plan give them. Its their theories which are truly illuminating. Much of life that is today we owe to these species.

Fossil science may not be my niche. However, facts you get to learn about various things when you discover a fossil are great. We try to answer questions like:

• How come this fossil is perfectly preserved?
• What sort of environmental conditions lead to this?
• How the earth's terrain was at that point of time? I.e. Its geology.
• What are the characteristics of that particular geology which lead to the preservation?
• What period this fossil belonged to? (Carbon dating, geological era).

Answering these questions give us a clue as to how the earth's surrounding could have been. Such evidences are corroborated with the other fossils they collect around that area or site. These again are basically theories. Then using these theories we try to figure so many other aspects of the fossil.

• How it lived?
• The shape it had?
• The unique bizzare features it had.
• Why those features where there in the first place...? (natural selection).

I'd normally want to type it all. However, I think these best way to communicate the fascination is via presentation slides.

So enter the Cambrain era...