larwils,
I'm sure others will deal more with what is
actually known, rather than just speculated, so I'd like to tackle the argument from another perspective, if I may.
This is the classic argument based on irreducible complexity, several components work together in such a way that the elimination of one, causes the whole to cease function. The mammalian inner ear bones are just such an example, remove either of the malleus, incus, & stapes, & the functional unit of inner ear bones will not function. Creationists would claim such a thing impossible to evolve, because all three components need to be in place for function to occur. However, both phylogenetic & cladistic evidence (evolutionary trees derived from morphological characters & molecular sequence data, DNA & protein) point to the evolution of mammals from a retile ancestor. Reptiles have a stapes, but no malleus & incus. The fossil record shows a gradual reduction of lower jawbones in the reptile-mammal transition series until only the dentary remains, the two bones were co-opted into the mammalian inner ear. Embryology shows mammalian inner ears have two components that begin at the lower jaw, & migrate to the inner ear during development.
Clearly, the origin of the mammalian, irreducibly complex, inner ear isn't in serious doubt. Yet imagine if we have none of the above lines of evidence. Would you be sitting at your keyboard now telling us how the mammalian inner ear is impossible for evolution to evolve? The point being, you aren't privy to the anatomy of the bombardier beetles ancestors, you are in no position,
because you possess no data to the contrary, to assert that the bombardier beetles squirty thang couldn't evolve. As such, the entire irreducible complexity argument is flawed on logical grounds:
Argument from Ignorance. Because the evolution of IC structures hasn't been proven, it must be false.
It would be nice to have a "flick book" of the bombardier beetles evolution, but simply because we lack such a thing doesn't mean various IC structures never evolved. It is a lack of information you are basing your argument, not a wealth of it.
Mark
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"I can't prove creationism, but they can't prove evolution. It is [also] a religion,
so it should not be taught....Christians took over the school board and voted in creationism. That can be done in any school district anywhere, and
it ought to be done." Says Kent "consistent" Hovind in "Unmasking the False Religion of Evolution Chapter 6."
[This message has been edited by mark24, 09-01-2003]