Tuesday, September 21, 2010
Absurd in the Highest Degree (Part Two)
On the other hand, even if this were the current state of evolutionary theory, "we can't explain this now" does not logically imply "it must be supernatural in origin." Too many phenomena, from lightning to epileptic seizures, that were once naturalistically inexplicable have turned out to have natural causes for that not to be obvious. And it's been pointed out to Ray several times that natural selection is not random chance, and that hearts, lungs, livers, etc. did not evolve separately in kangaroos and Kirk Cameron. Ray knows the phrases "common ancestor" and "natural selection," but seems resistant to actually understanding them.
Besides the eye, covered in part one, Ray focuses special attention on the ear and the nose. Both bear vestiges of an evolutionary history, supported by the fossil record.
Ray notes that our nostrils are used for both breathing and smelling, though this is not true of most fish. There is a Devonian fossil, Kenichthys, whose internal nostrils are intermediate between the typical fish position (in which the nostrils do not open to the interior of the mouth and hence could not be used to breathe) and the tetrapod position (in which they do open into the roof of the mouth). Over half the olfactory receptor genes in humans -- the genes that enable us to detect and identify particular scents -- are pseudogenes, disabled versions of functional genes in other species. If one is going to advance arguments from incredulity, perhaps a little incredulity would be in order to the idea of a Designer Who specially created us, decided that we didn't need a sense of smell as discriminating as a bloodhound's, and so rather than leave out these genes put them in and then crippled most of them.
Ray likewise notes the intricacy of the human ear, mentioning the three bones in the middle ear. The "hammer" and "anvil" have an interesting embryology, beginning, developing, along with the jawbone, from one of the "brachial arches" (sometimes miscalled "gill slits") in the embryo. This is unsurprising given the fossil record of the jaw and inner ear: these bones correspond to bones that formed the hinge of the jaw in early synapsids ("mammal-like reptiles"), and there are early mammaliformes and mammals in which these bones are diminished in size, no longer part of the jaw hinge, but not yet incorporated into the ear. Again, a small amount of incredulity might be reserved for the idea of a Creator Who left these bones out of the ears of birds and reptiles and amphibians, and included them only in the ears of animals for which an evolutionary explanation of them could be conveniently discovered and supported.
Ray ends the chapter by arguing that we don't need faith to know that God exists, because the Bible declares that God's existence is obvious from evidence. He doesn't really address the question of whether we need faith in order to assume that the Bible is correct on this point. Ray addresses the reliability of the Bible in a later chapter, but first he has (and hence I have) several chapters worth of misunderstandings of evolution to get through.