Proofs of Evolution: A Mediocre Debate (Faith, robinrohan and their invitees)

I want to discuss with Faith my and her understanding of evolution. However, we don't want it to be a Great Debate because we want expert input from time to time, if any is available. Her science is execrable and mine is just bad.We want to concentrate on the proofs of evolution, which I consider very substantial. Obviously, Faith disagrees.Over a hundred years ago, people did these digs and found a pattern emerging. The further down you dug, the simpler the organism was (in the form of fossils). This didn't just happen most of the time. It was always the case, if the ground was undisturbed.They figured deeper meant older. Later on they found a way to date stuff, which confirmed that deeper indeed meant older, and these things were, it turned out, very old indeed. They found some strange fossils which looked like a cross between one kind of animal and another. They found a lot of these.As time passed, they built up a "family tree" of life based on physical characteristics.Years later, along came DNA analysis. So they started analyzing the DNA of various species, and it turned out that the DNA analysis matched the "family tree" they had built up years before. It did not match all the time precisely, of course, but the match overall was very good.This message has been edited by AdminNWR, 12-19-2005 04:04 PMThis message has been edited by robinrohan, 12-19-2005 04:35 PM

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We are here as on a darkling plain
Swept with confused alarms of struggle and flight,
Where ignorant armies clash by night.--Matthew Arnold

I thought we were going to talk about proofs of evolution. If you want to re-do it, go ahead. Simpler means it has less parts. A bacteria has less parts than a raccoon. Makes sense that if evolution is true, it would start out simple and then get more complicated. There's no evidence for a flood. That's just Bible talk. What I mean is that there's a predictive element here. They dug up these proto-humans and said that their ancestors were apes. Then later they did the DNA analysis and come to find out we are in fact closely related to apes. That's very convincing.This message has been edited by robinrohan, 12-19-2005 05:36 PM

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We are here as on a darkling plain
Swept with confused alarms of struggle and flight,
Where ignorant armies clash by night.--Matthew Arnold

I'm not real sure about this. Here's where we might need an "expert." Anybody want to comment on complexity versus simplicity? I know of no such evidence rather than old tales. Well, they look pretty in between to me. They walk upright but their brains are smaller. If you are 97% genotype-similar, then your phenotype is going to be similar. The genes determine what you look like. But my point is they were saying this long before they could do DNA analysis.Then there's biogeography. Evolution provides an explanation for why isolated areas have weird creatures, like Kangaroos.This message has been edited by robinrohan, 12-19-2005 09:52 PMThis message has been edited by robinrohan, 12-19-2005 09:58 PM

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We are here as on a darkling plain
Swept with confused alarms of struggle and flight,
Where ignorant armies clash by night.--Matthew Arnold"It's a tale told by an idiot, full of sound and fury, signifying nothing."

I know you believe in "kinds," and in a sense that is natural. We don't see our dogs and cats giving birth to other creatures. That's how we got the notion of kinds.But if you look at this issue between micro- and macro-, I think we can reasonably say that this is a non-issue. All evolution is "microevolution" since the changes are so minute between each generation. But let's think about this for a minute. A momma gives birth to a little baby and it doesn't look exactly like the mother or the father. That's microevolution. Now if you keep this up for a real long time, and there are pressures on the outside that favor this or that change, you are going to have changes. And there is no way that this could stop just because you are a certain "kind."What does this mean, "kind"? It doesn't mean anything. There's a very good reason why they are so genetically similar. They had a common ancestor. Now if you go down the line and look at other creatures, such as me and my cat, you will find some genetic similarities, but not as many. What does that tell you? It tells you that we diverged a much longer time ago.This message has been edited by robinrohan, 12-19-2005 10:34 PM

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We are here as on a darkling plain
Swept with confused alarms of struggle and flight,
Where ignorant armies clash by night.--Matthew Arnold"It's a tale told by an idiot, full of sound and fury, signifying nothing."

Well, pardon me. I was just going by a common sense idea that we all have a notion of "kinds," Bible readers or not. A dog's a dog, a cat's a cat. I figured that's where that came from. I had no idea it came from the Bible. You haven't mentioned why there would be any limits. Now, I agree there are certain physical limitations. For example, a bird that was too heavy wouldn't be able to fly. But other than things like that, I don't see any limits. I don't think so, Faith. The naturalistic explanation is much more reasonable. We know there is Nature. We don't know there is God.This message has been edited by robinrohan, 12-19-2005 11:07 PMThis message has been edited by robinrohan, 12-19-2005 11:08 PM

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We are here as on a darkling plain
Swept with confused alarms of struggle and flight,
Where ignorant armies clash by night.--Matthew Arnold"It's a tale told by an idiot, full of sound and fury, signifying nothing."Our Nada, who art in Nada, Nada be thy name. Hail, Nothing, full of Nothing, Nothing is with thee.--Hemingway

"population reducing events"? What on earth are you talking about? No, it's not "in any case." In order to have a design, you need a designer. So you do know, but the rest of us don't. There's no evidence for God, Faith. Nothing objective. It's just your feelings.Not that I don't respect your feelings, you understand. But they are only feelings.--------------------------------------------------------------------------------

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We are here as on a darkling plain
Swept with confused alarms of struggle and flight,
Where ignorant armies clash by night.--Matthew Arnold"It's a tale told by an idiot, full of sound and fury, signifying nothing."Our Nada, who art in Nada, Nada be thy name. Hail, Nothing, full of Nothing, Nothing is with thee.--Hemingway

Well, what about the proof from the digs? The deeper you dug, the simpler the organism?

What do you mean?

-------------------------------------------------------------------------------- You don't have to go into great detail. Just give me an idea of what you're talking about. OK, no problem. I waive that point.This message has been edited by robinrohan, 12-20-2005 08:49 AM

If there were a group of 100 lizards, and they got separated into 2 groups of 50, then each member of each group will be mating with other members in that group, and they will continue to change through the generations. It doesn't matter if it's a 100 or 50. And if they are successful, pretty soon you've got 5000--all sorts of combinations.I would think this splitting would tend to make the groups different from each other faster. If both groups were successful, after a long time they would look a little different from each other, and after a longer time they would look very different.

I'm studying this book I got. I'll see if can understand a little more about "alleles." I'll get back with you.This message has been edited by robinrohan, 12-20-2005 12:51 PM

Ok, I've got all this mastered.Mere imperfect replication by itself could not produce evolution. If not for these other processes there would be no evolution.1. selection
2. mutation
3. gene flow
4. genetic drift
5. biased variation
6. movable elements
7. nonrandom mating.So if it wasn't for these things going on, there would not be enough gene variety for any life form to evolve over time. All of these processes don't have to occur, but some of them do. That's how you get to "macroevolution."

Number 6 is another way a mutation can occur. It's a gene that moves around on a chromosome. #7 is a preference for one particular type of a mate. The example given is of a certain female fish that prefers a mate that feeds in a certain place (rather like a woman who prefers men who take her to fancy restaurants). These particular males have some markings on them for some reason. The author says this can lead to speciation. I think I got the point. I'm just not sure I agree with it.I'll study up some more.

OK, I've read some of what you said on the other thread, and I think your point is that significant evolution cannot occur without mutation.I think I agree with that.But what about this scenario: (I copied this from a post I wrote earlier, elsewhere.)There's a group of little black furry creatures living in the forest called Eutherians. One day, one of these is born with some brown specks on his coat. This was due to a purely random mutation. By sheer chance, these brown specks are an aid to camouflaging in the bushes. The bushes are brownish too. There are some big bad predators stomping around, but the one with specks manages to hide, and it reproduces. Some of the others also make it through to adulthood. The speckled Eutherian gives birth to a litter of six, and five of these are speckled like its parent. All these live and breed but the unspeckled one is eaten by predators before it can reproduce.If you go through enough generations, all of the Eutherians will be speckled whereas before they were all black. This mutation was beneficial. Other mutations are neutral. Still other mutations are detrimental. The ones that are detrimental don't last through many generations. Whether the neutral mutations last is purely a matter of genetic chance. Natural selection will filter out all the ones that are detrimental.If one of the Eutherians was born white, for example, and white allowed the predators to spot him easily, he would not last long enough to reproduce.Would you agree that this type of scenario can and has happened?This message has been edited by robinrohan, 12-21-2005 02:10 AMThis message has been edited by robinrohan, 12-21-2005 02:11 AM

Actually, I also was not sure. I'm making the point that this is how evolution works, if you leave out all the other complications. This is the basic idea--natural selection plus mutation.But if it can change the coat color, it can do other things as well.Any mutation, if beneficial, has a good chance to be incorporated as a trait for a group. Given enough time, macroevolution can occur.But I want to know at what level your idea of Kind is--you said it was not the species level. Perhaps the family level? I think butterflies as a whole, for example, are on the level of family.