Vestigial Organs?

Hi, Peg. This is actually a fair question. I think the trouble is that, while the non-functionaltiy of the structure was the basis of the definition of the word vestigial, the non-functionality of the structure was not what made it evidence of evolution (even though many evolutionists like to focus on that point).What made it evidence of evolution was the fact that it represented a change: two organisms have the same structure, but with some differences between them, just as evolution predicts to see. So, while the term vestigial is probably semantically inappropriate for structures that still have a function, these structures are still evidence of the same evolutionary process.The extreme of this phenomenon would be a true case of non-functionality (the strictest meaning of vestige). These provide stronger evidence for common ancestry, because there is no reason for a truly non-functional structure to be present in an organism unless it is something that was originally functional.But, even the more relaxed version of vestigiality, in which some residual or secondary functionality remains, still represents a commonality in structure between organisms that is best explained by relatedness.Edited by Bluejay, : Rewording of "these structures are still evidence..."

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-Bluejay (a.k.a. Mantis, Thylacosmilus)Darwin loves you.

Hi, Faith.I realize I'm too late to get a response from you, but this is as much for those still participating on this thread as it is for you (I suspect you may still be reading this anyway).I have to say, I find the general concept of vestigial structures to be less useful for distinguishing evolution from the various "front-loading" or "post-fall degeneration" models, because they are the kind of evidence that both ideas predict to observe.But, when we take certain specific examples, such as the human coccyx, it becomes less clear. As Taq has said, if the human vestigial tail is to be explained as a degeneration of a formerly functional structure, this would suggest that humans were originally created with a tail or some other moveable structure for which muscles were required, and we are now only left with a corrupted, degenerate tailbone and some superfluous bits of muscle.As long as creationists are willing to accept this implication (that humans were originally created with tails), then I agree that vestigial structures do not support evolution over creation. If creationists are not willing to accept this implication, as I suspect most are not, then I think there is something for the two sides to discuss.You're free to contact me via PM if you want to talk more about this. If not, I won't be offended: maybe this post can serve as a starting point for other people to discuss the topic here.

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-Bluejay (a.k.a. Mantis, Thylacosmilus)Darwin loves you.

Hi, Peg. I’m not particularly concerned with how you want to view it: anything can be twisted to mean whatever the believer wants to believe it means. I think you need to do more than explain your viewpoint on the issue, because, as of right now, I see nothing, other than your viewpoint, that says what you claim it says.Think a little more critically: you’ve oversimplified the issue by thinking of it in terms of broad, abstract patterns. Look at the details, the minutiae, for just a minute. Take this, for instance: we can take a mouse, replace one of its genes with the human equivalent of that gene, and it can still function essentially the same way, with no apparent effects on its function. Yet, the human and mouse equivalents of that gene are different from one another.Why would a designer make a different model of each gene for each organism if those genes are functionally equivalent? Why not reuse the same parts and minimize the inefficiency of the system? Efficiency is one of the most basic tenets of design.----- You're still making the same error that has been pointed out already. Function has nothing to do with this debate, no matter how many times you assert it.Evolution also favors functionality, because non-functional organs and systems are a drain on the organism's resources. So, we don't expect animals to be walking around with unusable limbs and superfluous muscles sprouting all over the place: if such animals were biologically successful, it would be a fairly hard blow against natural selection as an important part of evolution.The reason we predict any vestigial structures at all is that the entire process of evolution cannot be perfect, and so, will not totally erase all clues of the genealogical history of an organism or species. So, organisms will sometimes have structures and functions that are essentially superfluous for their biological success.

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-Bluejay (a.k.a. Mantis, Thylacosmilus)Darwin loves you.

Hi, Peg. Do you know this for certain?
Have you tried? Do you know anybody who has tried?
Furthermore, if, for instance, a human and a chimpanzee produced a hybrid offspring, would you change your view on our relatedness to them?If not, then I think we should agree that reproductive isolation has nothing to do with your reasons for rejecting common ancestry.
If so, it’s still somewhat disingenuous of you to hide behind an assumed phenomenon that everybody here knows will probably not be legal to test in the foreseeable future.And, finally, what does reproductive isolation have to do with vestigial organs?
Do you believe that reproductive isolation is powerful enough evidence to sweep away all similarities?I see no reason to believe that reproductive isolation cannot be accomplished by evolutionary means, so perhaps you could walk me through your reasoning as to why reproductive isolation disproves common ancestry.

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-Bluejay (a.k.a. Mantis, Thylacosmilus)Darwin loves you.

Hi, Taq. Thanks for clarifying for me.I would also like to clarify that I don't suspect that this is true for all human genes: I'm sure there are some human genes that would have noticeable effects on a mouse's growth and development.But, the principle is still there.

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-Bluejay (a.k.a. Mantis, Thylacosmilus)Darwin loves you.