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Agahnim -> RE: What are birds (2/29/2008 1:46:29 PM)
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Darwin did not predict this, Darwin accommodated it after the fact. He admit (not predicted) the fossil record had huge gaps after it was known to have huge gaps. Creationism would predict the fossil record has huge gaps long before it was known and studied (that can be deduced based on the fact that the Bible said every organism lays forth after its kind. ie: we shouldn't see many transitions). You are confusing a prediction with an accommodation after the fact.
What creationism predicts is that there won’t be any fossils that could be considered transitions. (And this is a common creationist claim, “there are no transitional fossils.”) But this prediction is obviously wrong; I listed several of them in my thread at Christian forums. Even if you don’t believe these animals were actually related to birds, anatomically there’s nothing one would expect to see in a transitional fossil that isn’t found in them. This should be obvious, since they fit the descriptions that Gregory Paul and William Beebe gave before they were found of what a transition between dinosaurs and birds should look like.
The thing that was predicted before Darwin’s time was simply that not every animal that lived would be found as a fossil. Even though the theory of evolution didn’t exist in the modern sense before that point (although there were people like Lamarck), the presence of these gaps was a prediction made by uniformitarian geology, the original basis of the idea that the world is billions of years old. This idea, and its predictions, have existed for as long as people have been aware at all that fossils are the remains of extinct animals.
While I’ll agree that Darwin didn’t make this prediction himself, it was never a prediction made only by young-earth creationists. In fact, since young-earth creationists have predicted (and continue to predict) that no animals which appear to be transitions should ever be found at all, the nature and size of the “gaps” that exist in the fossil record are closer to what was predicted by old-earth geologists than by young-earth creationists.
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I don't think creationism or evolution can predict any specific anatomical structures. Darwin was wrong about a lot of stuff and that didn't falsify evolution and likewise if your alleged predictions were wrong, it won't either.
Evolution did predict these structures. Whether it can or not is not subject to debate; it predicted which groups of dinosaurs would have feathers, what the structure of those feathers would be, and how they would be arranged on the animals that had them. How on earth can you continue deny that evolution is capable of predicting the existence of anatomical structures after I’ve just posted two examples of it doing so?
If dinosaurs such as Microraptor were found to be unfeathered, I agree that it would not falsify all of evolution, but it would falsify the theory that dinosaurs are related to birds. Something that would falsify all of evolution if it were discovered is the existence of a high-level chimera—something with traits that are specific to two different taxa, such as a Pegasus, a horse with the wings of a bird. (And don’t give me the platypus as an example of this; the “bill” of a platypus isn’t the same structure as a duck’s beak.)
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As far a Creationist predictions, another one is that a Creationist predicted Natural selection long before Darwin (and Darwin stole that idea). The evolutionist prediction at the time was Acquired traits.
I asked you for predictions that are unique to creationism. Are you seriously trying to imply that creationists are the only people who predicted that natural selection happens?
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But if natural selection is such a profound idea, and Blyth published it before Darwin, then why isn’t Blyth’s name a household word? Perhaps because he was a creationist. It was not the scientific applications of natural selection that attracted attention in 1859; it was its presumed philosophic and religious implications.
I agree that Blyth came up with some of these ideas before Darwin did, and Darwin even acknowledged that. In the first chapter of Origin of the Species, Darwin wrote: “Mr Blyth, whose opinion, from his large and varied stores of knowledge, I should value more than that of almost any one”. The fact that he was a creationist doesn’t mean anything in his case, though, since Darwin’s theory of evolution didn’t exist yet at that point. Blyth accepted as much of evolution as it was possible for anyone to accept before Darwin’s time.
As I said, natural selection is not a prediction that’s specific to creationism, and the only reason the person who thought of it was a creationist is because he proposed the idea before it was possible for anyone to accept evolution. You seem to be saying I should expect him to have done something that would have been literally impossible for him, and treating it as significant that he didn't accept a theory that didn’t exist yet.
For the fourth time now, can you give me any confirmed predictions that are unique to creationism about specific anatomical structures? I’ve given you two of them from evolution, and by claming that evolution is capable of doing this you’re only showing your willingness to ignore the evidence I present you with.
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They are genetically more similar to us than an organism that is anatomically more similar to us. This makes no sense from an evolutionary standpoint, I would not expect to have a cousin be genetically more similar to me than a brother. I'm not saying that anatomical similarities can't be used to infer possible relationships to an extent, I'm just saying that it's not the only possible tool and that much of it is subjective either way.
Congratulations, this is the first creationist claim you’ve used here that I haven’t seen and refuted multiple times before. Talk.Origins refutes it, though:
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The second article describes the antibody genes of sharks. In humans, an antibody gene is assembled by mixing-and-matching various DNA segments, which are all found lined up on a chromosome. In individual immune system cells, antibody genes are assembled according to the following schematic:
Genome: V1-V2-V3-V4-D1-D2-D3-J1-J2-J3-C
Possible Antibodies: V1-D3-J1-C
C is a region Constant between antibodies, whereas the V, D, and J segments (Variable, Diversity, and Joining) are each drawn from large pools of segments.
In sharks, however, the arrangement in the genome is:
V5-D5-J5-C V6-D6-J6-C V7-D7-J7-C
(Note: the numbers are just used as markers; they don't signify anything else).
That is, in sharks the genes are already assembled, and these genes are arranged in long strings of such assembled genes (tandem arrays). Molecular genetic processes which can generate such tandem arrays are well-known. Also note that these same processes could take the shark arrangement and generate:
V5-V6-D6-J6-C V7-D7-J7-C
by a single step -- which looks a little like the human case. Further such deletions, especially working in conjunction with re-expansions by tandem duplication, could easily generate the arrangement seen in humans. Of course, this arrangement is not useful without the splicing machinery, but the shark example clearly disproves Behe's claim that antibody diversity requires the splicing machinery.
In case you aren’t able to understand that, what it’s saying is that the genetics of sharks are such that it’s easy for them to mutate in a way that has a superficial resemblance to human genetics. However, the way the genome is arranged that results in this is still fundamentally different from that of humans. This sort of thing is called “convergent evolution”, and it’s the reason why when comparing two animals on the basis of either anatomy or genetics, it’s important to make sure the similarities aren’t just superficial like this. The easiest way to determine whether they are or not is whether they’re the result of something that tends to change very quickly in animals, and in this case they are.
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Genetics for one. I think genetics is probably the most reliable indicator. Indeed, I've seen talk shows where a mother doesn't know who the father of her baby is and they do genetic tests to discover this (they don't merely look at the anatomy). Even so, much of it is subjective to an extent, I think genetics is very useful up to a certain point. The reason why we can make genetic inferences in this situation is because we can observe evolution creating certain kinds of genetic differences from generation to generation. However, we haven't been able to observe what genetic or morphological differences it would create after millions of years, that is only speculated.
I agree that genetics is useful for this also. It’s also possible to tell in some cases whether a genetic change is fairly recent or not, as explained in the Talk.Origins article I quoted, but this is a fairly recent field so it isn’t as well known as these sorts of things in paleontology. I also haven’t studied genetics as much as paleontology myself, and it’s off-topic in a thread about bird origins, so I’d rather not discuss it here. If you really want to debate genetics, start a new thread about it, and I’ll see if I can find one of the people I know who specializes in genetics to explain it there.
As I said, though, genetics can’t be used to determine this about fossils. Yet you seem to think that even with fossils, we should base our understanding of what constitutes a “kind” on more than just anatomical similarities. Since we have no access to the genomes of animals known only from fossils, what other than anatomical similarities do you think should be used to determine whether or not two of them belong to the same “kind”?
If you can’t come up with anything other than anatomical similarities that could be used for fossils, it isn’t subjective for me to state that a certain degree of anatomical similarity implies a relationship.
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