For Inquisitor, et al: What is Evolution?

I think I sort of volunteered for this so I'll start.Here's a couple of short forms (stolen shamlessly from another forum)Evolution: The process whereby a species undergoes a mean genetic change in the make up of the species over all; which is simply a change in allele frequency in a population over time.Evolution Theory: The theory which states that life has - by processes of random chance, natural selection, evolution and other unguided physical processes - gone from some initial simple state to produce by diversification, natural selection, etc. all life forms found currently on (and in) this planet.

And here are some links cribbed from someone else as well:
PubMed
Browse the Talk.Origins Archive
The Scientist - Science News, Educational Articles, Expert Opinion
World Scientist
Science | AAAS
Scientific American: Science News, Expert Analysis, Health Research - Scientific American
Nature

This one is cribbed from myself elsewhere:This question was asked:

How can evolution be a fact when the theory itself is not proven? That is the same thing as my saying that you should believe me because my theory is a fact according to my facts.First you have to know what a "theory" is. And very specifically a scientific theory. It is, as someone says, "not proven". It is an explanation of facts that has undergone a great deal of testing and work and discussion and arguing and assailing and so on and so on. Finally it gets harder and harder to poke holes in the explanation given and it goes from speculation, to hypothosis to theory. These are explanations of how something happens rather than what.As an example there have been two major scientific theories of gravitation. Newton's and Einstein's. Neither is actually a complete explanation. Both allow for calculations that predict the behavior of things in a gravitational field. Einstein's is more correct than Newton's because it more correctly predicts behavior in some extreme conditions than Newtons' does.
Now, it has turned out that Newton was in some details wrong. It may well be that there are flaws in Einstein's theory too. In fact there almost certainly are.However, apples still fall from trees. The fact of gravity is still there. It is this fact that both men were trying to explain the behavior of and (to a limited degree) the source of.The fact of evolution having occured was observed and considered before Darwin's time. Even though there wasn't the much more extensive fossil record we have today there was enough fossil and other evidence to tell observer's that something was going on. The problem then became one of explanation -- how could these observations be there?Darwin's concept was an explanation of how living things could evolve. It explained what was known at the time and predicted many more things. This is the theory of evolution. It is distinct from the facts. The facts were there when Lamarck put forward his erroneous ideas. The facts are still there after the original "classic" Darwinism has been modified into neo Darwinism. They will still be there when other changes are made.
Things evolved -- fact. How did things evolve -- Darwin's theory of evolution. The single word evolution is used for both a bit carelessly by all sides of the argument. When details are being argued the two have to be separated carefully.

and finally a description of the theory of evolution.I use the word description advisedly. You can't "define" a theory. It is too big and complex for that.Since we are going to discuss the theory of evolution we'll take as given the data that needs this theory to explain. There's a ton of that and you don't seem to want to start that far back.So the problem that Darwin was faced with is that the living things on earth had changed over time. How could this come about?He put together two concepts. One is that living things do not reproduce exactly. And from Malthus he realized that in the long run not all thing born will be able to live to reproduce.Putting these together we realize that there are things which influence which individuals do reproduce. A lot of it will be just dumb luck (the tree did or didn't fall on you) but that averages out in the long run. If individuals are different from each other then sometimes (maybe not often and certainly not all the time) that difference will enable one individual to reproduce and another one not to.Repeat this with a few billion individuals of different creatures alive at one time and then repeat that some 10s or 100's of millions of times and large differences could result if the environment allowed for the changes to be useful.That's the basic idea. Darwin needed some mechanism within a living thing that could allow for changes from one generation to the next. He had no idea what it would be.He emphasied that gradual change could do the job (he may even have said that was the only way it would happen I don't remember)He developed this idea after looking at a lot of extant living things and seeing the relationship between them. I can't find my copy of "Origin" right now and don't remember if he used any fossil evidence at the time. He was aware of the existance of obviously extinct fossils though. There wasn't all that much available in any case.This gives the basic theory. Then it had to undergo the beginings of a century and a half of examination and testing against new discoveries.A couple of huge areas of new information that support the theory are, of course, genetics and many, many more fossils. Both are exactly what the theory needed to underpin it and that it predicted would exist. The details have been filled in with methods that would have been deemed impossible in Darwin's day. Perhaps most noticable accurate, absolute dating of geologic structures. All that Darwin had was relative dating with guesses for the time periods involved.The genetic information has enabled us to see that relatively rapid changes are possible due to the kind of effects that even a few genetic changes actually have on the phenotype (what the animal looks like). They have also allowed us to see a trace, a hidden record if you will of the changes.The fossil information has filled in a bunch of transitional forms between major groupings. Amusingly the bird-reptile connection was found very shortly after Darwin finally published. Many more have come along since.

Finally I'll try to add something original.I'll try to word this all by myself and make it up as I go along. Each of these is intended to be independent.1)
Evolution is the result you get when you allow something to reproduce with some degree of difference in the "copies" and the "copies" are subjected to some winnowing process.2)Evolution is the process whereby a "population" of things can be changed by imperfectly copying them and winnowing them.3)Evoution is the theory describing how living things came to the state they are now by the process of "imperfect" reproduction and differential survival.[This message has been edited by NosyNed, 05-01-2003]

Uh, Inquisitor is this what you wanted?
Are you still in the middle of reading it?

You're off topic.

How can you make any probability calculations about a process that very little is known about?When you assume a large number of atoms, that have to react purely randomly (all possible combinations are equally likely) and have to produce just one specific output (only one pattern in a protein for example) you arrive at a tiny probability that is a good enough representation of zero.So, that's obvious to most everyone. And that's not what anyone thinks got life started off. And, one more time, that's not evolution of living things. You don't make much headway in arguing against the evolution of living things by saying there can't be any living things in the first place. Once there are there what happens is the quesion answered by the ToE.So the question is not "How could that happen?"
The question is "What could have happened?".There is current research into the topic. It is way beyond this kind of issue. If you want to discuss find one of the abiogenesis topics or open a new one.

No, you don't. The ToE (neo Darwinism ) is specifically defined to be talking about changes in living things. It says nothing about how they got there. It says nothing about cosmology.Darwin made this clear at the very beginning.If you use the word "evolution" to mean just "change" then, fine, it can be applied to almost anything. But that is not what the discussion is about.I'm sure that most "evolutionists" (whatever that is) "believe" in the BB, plate tectonics, special relativity, quantum mechanics and so on. So what?There is a tendancy for individuals who use evidence and reason to arrive at what they accept as most probably true to arrive at the same places. Why is this surprising?The only reason you've got them all jumbled up and lumped together is because you don't like the outcome from all these different scientific disciplines. Too bad."It had to start somewhere. Right??"
Yup, but there are different ideas of how. There are lots of scientists who "believe" in the big bang but think that God kicked it off.Evolutionary biologists know it had to start somewhere. Most of them don't pay much attention to that as they are concerned with what happened afterward and happens now.Others (chemists rather than "evolutionists") are working on issues regarding the origin of life.Physicists and cosmologists work on how the universe started and how it behaves. I'd be very surprised if many of them give a wee thought to life and it's evolution very often. It simply isn't something they are concerned about in their work.Could you explain why you have such trouble separating these areas of inquiry?

Oh, really? It is the reconciliation of all the different disciplines that re-enforces the conclusions.Physicists and the cosmologists get comparable dating for the universe as a whole by different methods.Physicists get absolute dates that agree with the relative dates of the geolgists by independent means.Paleontolgists get relative dates that agree with the geologists.Biologists (Cladists) get relationships that agree with the geneticists by independent means.The whole is greater than the sum of it's parts.You claim "unattenable hurdles" without being able to coherently explain any of this.

You're way off topic here. How about going over to the flood and explain how you can pile water up on something to make it push down on it.

I'd say close it to new posts until someone wants to ask the question again.It was my thought originally that it would act as a place to refer to rather than go through the whole mess each time someone asks.