guys thanx for ur replies.. anyway i ill drop the question for a while..

[dudenexdoor1]

recently i read in a book that life forms couldnot have got more and more complex(order) with time because of entropic reasons .. ur thoughts??

[Clanad]

You'll find, I'm sure, the raging disagreement on an answer for your question will focus on the definition of a 'closed system', which is part and parcel of the classic explanation of the Entropic Principal. For what it's worth, I happen to believe that the solar system and, for that matter, the universe constitue the requiste 'closed system'. Others will disagree and we can each cite our expert sources...

[ll_billym]

Well life forms have got more and more complex so that is that really.

[mibn2cweus]

The solar system is one example of increased order and complexity in the universe. Star formation is another. The universe existed millions of years without the elements necessary for life. These were cooked up in stars and from these, more complex elements, life forms such as us became possible. We are all children of the stars.

If you require more recent evidence of increased complexity and order, tear open your computer and take a look!

[Clanad]

Not exactly correct, mibn. Fact is, current theory states that within the first three minutes of the universe�s existence, stellar burning produced all the elements heavier than hydrogen and helium. Supernova explosions (dying stars) provide the most efficient mechanism to enrich the gas between stars with these heavier elements. Theory also suggests that the earliest (10^-43 seconds) condition of the universe consisted of a proton plasma of an unimagineably high temperature which has cooled to near Absolute Zero Kelvin now. This is one segment constituting the classic definition of entropy. We also know, that the Cambrian Explosion around 500 million years ago produced many more phyla than exist today, another constituent of entropy. As far as your computer is concerned; if you didn't think it would run down and fail, why did you buy the extended warranty?
Seems I referenced a raging disagreement focusing on a 'closed system' and the Entropic Principal...

[dawkins]

well dudenextdoor1 the book where you gleaned that piece of work from was a book on "creation science". Creationists, IDer's or whatever are fond of misrepresenting science to discredit other science that makes them uncomfortable. A quick glance at the entropy law will show it refers to closed systems and the earth - which relies on energy from the sun to support and devlep life - is certainly not a closed system. Think about how you grew from a single micrscopic cell into the billions of cells you are today and think about how that happened. You are also an open system in that you need to take on energy to enable your development.

It is certain that, eventually, the sun will run out of fuel and evolution will fail but not for another 15 billion years. Until then it can carry on regardless.

D

[mibn2cweus]

dawkins, On my behalf, welcome to AB forums. Entropy is certainly a reality but there are in fact two sides to that coin. Life is as much an aspect of reality as death and, (in respect to the survival and welfare of humanity), reason serves the former much better than the alternatives.

[dawkins]

sorry Mibn far too philosophical for my tastes. not sure what your point is in relation to my comments. In most species death is a far more likely outcome than maturity, occuring as a result of predation and resource competion. But as long as sufficient numbers of a population survive long enough to breed then adaptations through random mutations will occur. It is inacurate to say life gets more and more complex. rather, it adapts through random mutations as a result of selection.

D

[Clanad]

Could you explain dawkin, a little further, your intended meaning of '... it adapts through random mutation as a result of selection'? Totally lost me there...

[dawkins]

Sorry Clanad. I didn't explain my point very well.

It is common to assume that evolution is a process by which living things get more and more complex. i.e. that man is somehow the pinacle of an evolutionary process and is the most complex of all organisms, or collection of organisms, which ever you prefer. However, we all know that to assume makes an ass out of you and me. Evolution is, put simply, change over time and this change actually takes place at the genetic level through the frequency of particular alleles within the gene pool. Evolution is not the search for complexity as this would suggest some purpose to evolution which simply doesn't exist. Instead, evolution is an accumulation of random mutations that by chance provide enough benefit to the host to become typical in the genetic traits of that population. Since populations - or, indeed, individuals within populations are not closed systems and since increased complexity is an inaccurate way of describing evolution then the 2nd law does not apply.



D

[Clanad]

Thanks for the clarification, dawkins... although we probably disagree your explanation is well presented. I was having difficulty understanding your intent concerning '...as a result of selection' as it applied to random mutations...