Fossil Record as the Strongest or most compelling evidence of Macroevolution

This is a spin-off topic, of the "Strongest or most compelling evidence of Macroevolution?" topic, which is currently at message 33Go nuts!Adminnemooseus

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Could you explain that in much more detail? Given the fossil record I don't see how you can come to the conclusion that life on earth hasn't evolved?
Could you describe what you think has produced the fossil record? I would suggest a new thread if you have any real logic to back your theory up as it may go on for awhile and would derail the title of this thread?
--------------------------------------------------------------------------------I'm just saying that the Fossil record itself is not hard evidence for evolution. First of all the Fossil record's pattern of "smaller to bigger" organisms does not exactly say that "These organisms evolved", one can infer that this is what happened but it is not certain...What has produced the fossil record? I really don't know why the record shows what it does. I have heard theories, none of them proving to be totally valid, it is really a mystery of life itself.
What I am saying is that your theory really hasn't been proven truly valid.------------------
"I tell you the truth, no one can see the kingdom of God unless he is born again." -JesusJohn 3:3

"proven"?
We simply go with the very best explanation we have right now. It has stood up very well to a great many attempt to falsify it.What pattern of "smaller to bigger"? Is that all you know about the fossil record? Perhaps we should back up a step and you should describe what you think it does show. We can't discuss theories explaning the evidence until we have some idea of what that evidence is. It sounds, so far, from your posts, that you have no idea what the fossil record actually looks like.You have "heard theories" none of which are totally valid? One of them hasn't been falisfied and has shown enormous power to predict what we do see. Only one!You have none of your own to suggest as a replacement? Let's back up to the evidence then and after that you might be able to find one you like better.

How about I try to give a start on what the fossil record looks like. This is only a tiny little overview of it and maybe we will need a lot more as we go along. (I'm also doing this from memory as I don't think that a few 10's of Myrs one way or the other matters to the overall framework)1) The oldest rocks on earth are just over 4 Gyrs old (4,000,000,000 years).
2) The earliest things that appear to be fossils of unicellular life are about 3.5+ Gyrs old. These are reasonably likely to be fossils of life but there can be some arguement.
3) Way before 1 Gyr there is good evidence of unicellular life.
4) From 4 Gyr to 1 Gyr no evidence has been found for multicellular life.
6) At about 600 Myr multicellular life becomes apparent.
7) At about 550 Myr mulitcelluar life with many basic body plans and some hard parts allowing for fossilization are found.
8) Todays basic phyla are present at the 550 Myr mark but are very simple. (e.g., worm like with no 'real' backbone to represent cordates (that is US) )
9) Somewhere around 350 Myr we have fish, insects, worms, etc. We have no reptiles, amphibians, mammals or birds found at all.
10) Amphibians appear next. There are no reptiles etc.
11) Around 250 to 300 Myrs ago we find reptiles.
12) Somewhere around 200+ Myrs ago we find a series of fossils that show a clear transition from reptile features to mammels. And mammels are found from then on.
13) This sort of pattern continues. There are clear points where new taxonomic forms appear for the first time. They then show ongoing diversification after that.
14) Another pattern that becomes more apparent in the last 100 Myrs is that the life forms become more and more like those alive to day.
15) There is no monotonic pattern from smaller to bigger.
16) There are sudden, dramatic losses of large numbers of species and genera.
17) After these large losses there is a diversification of the survivors to fill empty niches.Ok, how is that for the fossil record? Do you need a lot more detail? If you do I think you might need to go to specialized sources. When you know what the fossil record actually is *then* you can comment on it's value in drawing conclusions. Until you do know you have nothing to comment about and would be well to say "I don't know."The is but one theory that explains all of the above and a very, very, very large amount more. It may not be "proven" but it sure looks like a very good horse to bet on in this race.Now back to the two meanings of the word evolution. One is the theory of how all this happened (the ToE) that is what is not
"proven". The other meaning is that life has, through some mechanism, changed and diversified on earth. That meaning is "proven", it is simply the facts as laid out above. You don't have any problem with that, do you?

The fossil record is good evidence for evolution. Their is better, though. For example, vestigal remanents, genetic similiarites, and the whole science of molecular biology.Why smash a hole in the ground with a hammer when you can use a jackhammer?

That a separate thread Hare. The one that this one spun off of. You could elaborate there if you want.{Note from Adminnemooseus - In all fairness to the Hare, that other topic was closed when he posted the above. Indeed, his posting the above was the prime reason for me re-opening the other topic. I quoted the Hare's message in the re-opening message over there.}[This message has been edited by Adminnemooseus, 11-09-2003]

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I'm just saying that the Fossil record itself is not hard evidence for evolution. First of all the Fossil record's pattern of "smaller to bigger" organisms does not exactly say that "These organisms evolved", one can infer that this is what happened but it is not certain...

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That's part of the problem, though: the fossil record *doesn't* go from smaller to bigger. It goes in all sorts of different routes - including tiny fossils in the same strata as huge fossils - but they're *always* confined to a specific set of strata. Why?------------------
"Illuminant light,
illuminate me."

I must agree with IronMan on this point. The Fossil record cannot itself be used as evidence for evolution. That is because the fossil record is used to create the theory of evolution. We even refine the theory based on accumulating fossils in the record.What does count as evidence for evolution is each NEW FIND within the fossil record that fits the current model (and thus was not part of its construction). That is to say every correct prediction by the model regarding the next find is a form of evidence that the model used was correct.Evolution is certainly the best fit so far, and the most appealing based on how we see the world working today. But we cannot say what we used to create our model, proves our model.------------------
holmes

We aren't saying it "proves" the model. It is the evidence used to arrive at the model in the first place. It is powerful evidence for it anyway. All the evidence explained by a model is "for" it. It isn't always as impressive and convincing as further evidence that is predicted by the model.However, it is evidence for the fact that evolution has occured separately from it being used as an input to the formulation of a model for how. Don't mix the two meanings of "evolution" up here.

Ohhhhh, maybe I'm confusing both evolution and proof.Let me put this another way and see if it means I am not understanding what your were talking about, or vice versa.The Fossil Record is simply that, a collection of fossils layered in different strata. By themselves they do not really give evidence of anything except for what life was like at a given moment in time.Uniformitarianism (originally applied to geology) was applied to biology, specifically with regard to observations of breeding and changed within species, which allowed us to connect dots between layers. Thus we began to connect dots between moments in time based on current rules of behavior.The fossils correlate highly with a model based on this projection. But it was not the fossils themselves which led to the model, they are in a way model neutral. You could (and many have) come up with all sorts of models based solely on the fossils which may have "worked".The problem arose (and continues to arise) in fitting those other models in with observations of how life works today, and our assumption of uniformitarianism.A good mental experiment would be this. You find a trilobite, and somewhere else (later) in the geologic column a legbone. Then you keep finding more varied structures throughout the column. How would those bring you to the conclusion that 1) over long periods of time that fossilized life form could change the into other fossilized life forms, 2) so much could change occur in fact, that they all basically originated from one form?------------------
holmes

The fossil record says that life at different times was different. I don't think this requires any biological extra assumptions. They do give a series of snapshots of what life was like at any given time. But that is *not* all that they tell us. They all so say that there were *changes* from one snapshot to the next.Getting to a mechanism of how life managed the changes does seem to require a uniformatarian assumption. That is that life forms gave birth to other life forms in a chain just as they do today. Now we have a problem of explaining how the differences could arise when that is going on. This becomes the ToE.But the change in life forms is there separately from that. To apply the word "evolution" (in our current form) to that change then requires the birth from previous forms assumption. So I will give you that one. If you don't want that assumption I guess you could stretch "evolution" to mean the overall change in life forms but I think that would be streaching it too far. I leave it up to someone else to suggest what word would be applied without the given assumption.All sorts of models could have worked? It is pretty hard to manage to find them. A large number of special creations is the only one that I'm aware of that seems to match the information. Can you suggest some others that have been considered.

Ahhhh you'll probably kick yourself for not having thought of Lamarke, or how about the Greek theorists (they argued for forms of interchangable parts)?I am not going to go through a bunch of names (and it is doubtful I can remember more than Xtian, Greek, and Lamarke), but you can find different concepts springing from a similar geologic theory... catastrophism.Essentially if you don't believe life must generate from places that we see, or that it must start small, catastrophes may allow species to emerge from inside the earth, or equally cause some species to just change (and not in the gene-mutational sense), almost rupturing into new beings.Crazy stuff.------------------
holmes

I'm not sure (I'm stepping out into a space I don't really want to defend but just for fun let's go there) that it makes a big difference to the ToE if we accept Lamarke's inheritance of acquired characteristics as the mechanism for heredity.Let's see what happens. Darwin simple said that individuals were born different from their parents and then we selected.If acquired characteristics were as Lamarke said then we have individuals being born different from the form of their parents at the birth of the parents. The selection process can still be applied but now there is some greater chance that the modification will pass the selection sieve.It is a bit different but the overall model is the same.As for the other "models" they sound like special creations which I mentioned as a competing model already.Any comments?

Holmes said:

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The Fossil Record is simply that, a collection of fossils layered in different strata. By themselves they do not really give evidence of anything except for what life was like at a given moment in time.

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I believe NosyNed has already commented on this, but I'll also.As stated in the quote, the fossil record is a record of the nature of the varities of life forms at a given time. It shows that the varieties has changed down through time. This is the FACT of evolution - the nature of life on earth has changed through time.How this change came to be, might be explained in more than one way. Possible ways would include some variety of progressive special creation, or what has come to be known as the theory of evolution.But the fossil record DOES NOT support a one time, young earth creation of all life.Moose

I agree that Lamarke is more a mechanism difference than a complete model difference. I guess this would only effect whether fossils suggest the strict form of the word "evolution" (Darwinian model). Well this could be the case, although that would be a pretty general use of the word "creation", and they certainly do not involve deities.One idea is that lifeforms are generated elsewhere and emerge (from underground?) during cataclysms. Thus new forms in the record come from elsewhere and are unrelated to other forms in different parts of the column.Another involves the active mixing and matching of limbs to develop new species (I forget under what circumstances). Those theorists would have loved the platypus.But another "catastrophic" theory involved special environmental conditions which allowed for sudden metamorphoses in individual beings to others. Like imagine a volcano explodes and suddenly people twist and "convert" into some sort of fish-beings to escape into the sea.Certainly that last one would fit the fossil record. Catastrophes seem to mark major changes in fossils. It would also NOT really fit in with an idea of "creation" of each species, the change is internal. Why don't we see any evidence of this happening today? Easy... the conditions haven't arisen yet!Heheheh.------------------
holmes