"Evolution is a chance process"

[Bread_of_Life]

Do evolutionists believe that evolution is a chance process?

All too often I am accused, usually without my having been asked, of believing that life, and it's associated adaptive complexity, came about "purely by chance". Sometimes this accusation is made personally of me, but more often it is made in general of evolutionists.

Of course, it is untrue, and comes from a basic misunderstanding of the evolutionary process. There are no evolutionary scientists whatsoever who believe that evolution is purely a chance process, or that a significant ammount of adaptive complexity can come about purely by chance.

What is evolution?

Variation

Evolution is a two step process. Those steps are variation and selection. Variation is, as far as we know, purely a chance process. Mutation and sexual recombination produce changes in our genetic code basically at random - meaning that every generation is slightly different from the last. Over a period of time, and a large population, this creates significant ammount of difference between members of the population - variation.

The struggle for survival

The second step in the evolutionary process I have called "selection", but that is a rather deceptive term, because usually selection requires a selector, a conscious act of selecting one object over another. This does not occur in nature, as far as we know.

What does occur however is a struggle for survival and resources. What Darwin realised is that there are not infinite resources (food, mates etc) available in the animal kingdom. If there were, then there would be a population explosion. What actually occurs is that most populations stay approximately the same, or oscillate around some mean. That means that there are limited resources available to the members of these populations, and that means that members of those populations have to compete, because there isn't enough for everyone.

In fact, there's not nearly enough for everyone. Some fish lay literally tens of thousands of eggs in a lifetime, yet for a stable population, only one of these eggs per fish will ever go onto survive to adulthood and breed themselves. That's a pretty depressing statistic for fish - because it means that literally thousands will die or be predated before they reach maturity, or be infertile for some reason.

Fitness - winning in the struggle for survival

An animal is said to be "fit" when it possesses features that increase its probability of survival and breeding. Variation is random, and therefore, not all animals will be fit. Some will end up, by chance, possessing features that lower their probability of survival and breeding - making them positively unfit! Some will possess features that make them neither more or less fit than their average peers. Some will happen to possess features that make them more fit than the rest of their peers. The randomness and chance of variation endows a lucky few with features that make them fit, giving them the upper hand in competing against the unlucky rest.

But of course, you'll see what that means immediately. Whilst variation is random - it gives animals a random selection of features and adaptions, some of which makes them fitter, and some less fit, and some no more or less fit than their parents - selection (survival of the fittest) is not random. Far from it - over a period of many generations, on average, only those who were lucky enough to be endowed with fitness enhancing variations will survive and breed, and therefore a population will accumulate fitness enhancing adaptions. If selection were a random process evolution could never succeed - because a random sample of fit and unfit creatures would move to the next generation.

But because some are fitter than others, this does not happen. The more helpful the adaption, the higher the chance that it will be passed on and spread. The more harmful the adaption, the less chance it has to be passed on and spread. In that way, the struggle for existence acts as a non-random filter, filtering out the bad chance variations, and keeping the good chance variations. That way, after a number of generations, only fitness enhancing chance variations remain, having been non-randomly allowed through the survival and breeding filter. In other words, that one fish that survived out of tens of thousands is likely to be one of the ones who happened to be best equipped to survive - and is therefore going to pass on genes that will equip the next generation to be good as survival.

Conclusion

The conclusion is that evolution is essentially a non-random process. Whilst variation does randomly throw up good and bad and neutral mutations and adaptions - the struggle for existence and breeding filters out all the bad adaptions, and favours the good adaptions. After a few generations, only the good adaptions remain - because the bad adaptions that were randomly thrown up by variation have been filtered out.

The idea that scientists believe that life and adaptive complexity came about randomly is untrue. It didn't. It came about because of filtering, which by it's very definition is a non-random process. A sieve doesn't randomly let through particles - it only lets through the ones small enough to get through. Natural selection's sieve doesn't let things through randomly either - it only lets through those creatures who happened to possess features that increased their probability of survival and breeding.

Hope that helps!

Nik

[barracuda]

Helps with what?

[Bread_of_Life]

Erm, with the general educational level of the boards about evolution? Helps answer creationist claims that evolution is a random process? Helps break up the boredom and feeling of existential aloneness inherent in life?

[Guest mscoville]

Whilst variation does randomly throw up good and bad and neutral mutations and adaptions

Randomly.

~M

[Guest mscoville]

What were the chances that all the forces and elements necessary for a life permitting universe should have been created and properly alligned during the big bang. That's a real question, just so you know. I was interested in that, and I can't find an answer.

~ M

[Old Timer]

SA, your lead post on chance is amazing. I know to cut and paste is a no-no but I have kept it as brief as possible. The full article is at AiG.

It cannot be stressed enough that what natural selection actually does is get rid of information. It is not capable of creating anything new, by definition

[Steff]

I surprised people still quote AiG with all the false information and outdated information they still have on their website. It's a wonder that they don't argue the world is flat and the center of the universe still.

The argument they seem to be following here is the second law argument that energy or complexity of a system tends to decrease. However what they have failed to mention that this second law argument in recent years has been found to be false. The Second law was primarily founded on Bolzmann's work involving inert gasses in chambers, however when you change the experiment all of Bolzmann's claims do not stay true. They have found that not in all cases does the general energy of a system decrease.

Edited May 29, 2004 by Steff

[Guest arkon]

Variation is, as far as we know, purely a chance process. Mutation and sexual recombination produce changes in our genetic code basically at random -.....

Ok, so variation , which is thru mutation...is random..

Mutation has been observed to always be negative.

So what we have here is negative randomness...which works AGAINST survival.

natural selection

The second step in the evolutionary process I have called "selection", but that is a rather deceptive term, because usually selection requires a selector, a conscious act of selecting one object over another. This does not occur in nature, as far as we know.

Basicly what was said here is that the ones that dont get eaten, killed by some other reason, and make it to the food first...have the better chance. There is still one more thing to look at, so we cant say that the animal will survive, it just has the better chance. (chance)

So we have luck, (that its not eaten) , we have luck, (that its not randomly killed by anything else), and we have luck (that there was food to find and it found it first)

Sounds pretty random to me.

But of course, you'll see what that means immediately. Whilst variation is random - it gives animals a random selection of features and adaptions, some of which makes them fitter, and some less fit, and some no more or less fit than their parents - selection (survival of the fittest) is not random.....

Fitness, survival of the fittest.

Basicly what we see in this is:

The animals that survived the first two quotes (above) are pronounced the most fit, and will survive. (being that the weaker ones did not survive).

So this is based on the randomness of the first two.

SA.. you sure went a long way to try to make random into something different.

If no one or nothing is selecting by some plan, then it is not selection. No matter what term you make up for it.

This whole idea is blown out of the water the first time a robin rears the young of a natural competitor. The first time a lioness nurses a hyena. The first time a ...etc....

you get the idea. In your imaginary survival scenario...those things dont happen. They do happen in real life.

[artsylady]

SA:

The first fish or fishes that grew stumps where the fins were. What advantage was it to them to flop around on the sand with stumps for a thousand years when they'd be much further ahead with fins swimming around in the water?

[Guest LCPGUY]

SA:

The first fish or fishes that grew stumps where the fins were.  What advantage was it to them to flop around on the sand with stumps for a thousand years when they'd be much further ahead with fins swimming around in the water?

Hey Artsy babe,

that was GREAT

:laugh: :)

Go Girl GO!!!

Bro John