Evolution and Thermodynamics

[jdavidw13]

Hello,

I can't see how evolution get's around the problem of the second law of thermodynamics? If a system can't go to a state of higher complexity without a planned and guided change, then how could the "primordial soup" spontaneously form complex molecules???

 

--Confused in colorado...

[special j]

nature's guess and test -- mutation is a fact of all life as we understand it and occasionally, that mutation benefits the being allowing it to breed more than it's peers.. no plan is needed because it is no more than a chance occurance that happens to suit a social or enviromental situation.

 

edit: i guess you could call reproduction the plan for evolution tho -- there is a method to evolution, wouldnt that in itself qualify as a plan? jus my 2 cents.

[jdavidw13]

Well that doesn't make much sense... Adding more entropy into a system will not increase the order of the system. Entropy, being the measure of randomness and disorder of a system, can't reverse its self by using more entropy.

 

I could understand how a planned and guided mutation could bring about ordered change, but not a random one... This is just so confusing. I just can't make it agree with my commen sense.

[special j]

so, just to be clear -- your common sense pulls you rather towards a creator entity planning the evolution of life? To assert random biological mutation could simply not work based on constraints of chemistry, and that all progress must be planed, would suggest to me a conclusion of a creator..

 

What If: All the chemical precursors are located separately on a mountain side. An earthquake occurs resulting in a mudslide. Now all these same chemicals are mixed together in a puddle located at the bottom of our mountain --

 

allowing no possibility for random occurrences over millions of years based solely on rules of thermodynamics seems ignorant to me i guess, but that is just me, no insult intended. perhaps someone here with a chemistry background would like to pipe-up. peace.

[jdavidw13]

So we have a system where all the building blocks of life have been included. All it takes for life, or complex molecules, to form is just to mix them all together like you suggested, or by any other means? Even if by chance you may form the building blocks of life, it would take a whole series of random chance happenings, happening at all the right moments to form even the simplest of life forms.

 

Yet, by the laws of nature, if you can get something to form in that system, it will start to tend toward greater disorder or lower energy states. If simple life forms did come about in such a way, it would require all such steps in the formation of life to go against it's tendancy of entropy.

 

Like I said before, if left to itself, a system will tend toward greater entropy. A guided change is required to move a system to less disorder and a higher energy state.

[Andrameleh]

The system you 've been talking about is not isolated!!!! Therefore energy is incoming and entropy is redused in the system. Order can be "created" from a chaotic staring condition without any "help" from a supreem being. Take the following example for instance : Iam sure you 've all noticed how small and biger pebbles tend to gather toghether in parallel lines due to the wave movement on a sea shore , there is no divine intervention in that , just the lowes of nature working.

[jdavidw13]

The 2nd law still applies in an open system. Granted, that if there is an influx of energy, then equalibrium can be achieved, maybe even a slight degree of complexity, but the system is still tends towards disorder. Life, which is very complex, requires a highly ordered arrangement of energy and matter, in which any random influx of energy cannot provide, ie. natural earth proccesses.

 

Even in an open system, energy and matter must be arranged according to a plan. Sunlight, air, and water is not all that is needed for a plant to make food. That influx of energy and matter must be arranged from a plan, it's genetic code.

[deamonstar]

I think that the confusion here lies in the fact that we are trying to apply the laws of thermodynamics to a scale too small for the overall entropy from the original starting conditions. Remember that the ORIGINAL starting conditions come from the moment of the big bang... a time of near infinite energy and temperature. Over time entropy is decreasing as well as temperature and overall energy. as energy decreases, elements and metals and further complex compounds and chemicals form... all of which have stored POTENTIAL energy. it is when these chemicals combine under certain circumstances that chemical reactions can occur, releasing this potential energy and thus on small scales the entropy IS increasing... leading to all sorts of pontential chemical combinations.

remember that this process has been occuring for BILLIONS of years throughout the ENTIRE universe. it is not surprising that chemical combinations such as dna are inevitable... as the obvious evidence (ourselves) points to.

[TeleMad]

jdavidw13: The 2nd law still applies in an open system. Granted, that if there is an influx of energy, then equalibrium can be achieved, maybe even a slight degree of complexity, but the system is still tends towards disorder.

 

I agree that even an open system TENDS towards increasing disorder, but don't forget that tendency and behavior are two different things. For example, The Moon has a tendency to fall straight down into Earth, imposed on it by gravity - the Moon also has a tendency to continue moving in a straight line at constant speed, imposed on it by inertia.

 

Yet the Moon's behavior differs from both tendencies:neither is realized. So although even an open system tends towards increasing disorder, the influx of energy can permit it to undergo decreases in disorder. This is how biology works. Living organisms are open system, exchanging both matter and energy with their surroundings (for example, we eat, inhale, exhale, defecate, urinate, sweat, etc.)

 

This flow of energy is channeled by cells into maintaining, and even increasing, their order. For example, using such energy, proteins are made from free amino acids, which involves a decrease in entropy (an increase in order). If these local decreases in entropy didn't occur, then a single-celled zygote couldn't transform into a 100-trillion-cell human body with its multiple cell types, multiple tissue types, multiple organs, and multiple organ systems, all working together in a highly orderd and complex interdependent network to allow us to live?

 

(edited by Tormod just to test line break functionality)

[alexander]

Hey guys check out this web site...

http://evolution.berkeley.edu/

There seems to be a lot of discussion about evolution on this site, and a lot of people don't seem to beleive in evolution because they dont understand it. This website will hopefully answer your questions.

[Guinness]

If you find this an interesting topic as I do, I would recomend reading this http://www.amazon.ca/exec/obidos/ASIN/0195121058/qid=1086790419/sr=1-1/ref=sr_1_2_1/702-4108954-6600056 book bu Stuart Kauffman.

[sanctus]

Originally posted by: deamonstar

Over time entropy is decreasing as well as temperature and overall energy.

 

Are you sure about entropy decreasing? I mean the universe is a closed system therefore entropy stays constant or increases (at least that is what I've learned).

[TeleMad]

Guinness: If you find this an interesting topic as I do, I would recomend reading this book bu Stuart Kauffman.

 

I personally didn't care much for it. I've got a copy if someone's got a few bucks ;-)

[TeleMad]

sanctus:

 

 

 

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deamonstar: Over time entropy is decreasing as well as temperature and overall energy.

 

 

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Are you sure about entropy decreasing? I mean the universe is a closed system therefore entropy stays constant or increases (at least that is what I've learned).

 

Yeah, you're right: the universe's total entropy increases in every reaction that occurs (even if local decreases in entropy happen).

 

 

 

His last part was also incorrect...overall energy is not decreasing - for it to do so would be a violation of the first law of thermodynamics. Overall energy is constant, but it is diffusing over time, becoming more spread out and more evenly distributed. At some point in the future, there will be no more "energy hills" and no work will be able to be done: this is called the "heat death" of the universe. (Note: technically, energy is not conserved: "mass-energy" is).

[Tim_Lou]

yes, reactions favor increase in entropy and decrease in enthalpy (did i spell it right?)

 

but!!

reactions of building up living molecules are highly unfavorable.

it decreases in entropy while increases in enthalpy.

 

just like photosynthesis....

[Uncle Martin]

Originally posted by: sanctus

Originally posted by: deamonstar

 

Over time entropy is decreasing as well as temperature and overall energy.

 

 

 

For an "outside the envelope" theory on entropy take a look at everythingforever.com

I don't know if I accept all he claims, but it is an interesting read.