127: Creationist Confusion about pharyngeal homologies
Gosh, cranial nerve distributions are nearly identical in fish and mammals! There are some interesting differences—cats lack lateral lines and gills, of course, and they are separated by several hundred million years of evoluton—but overall, the similarities are overwhelming.
Alas, poor Serge. He has made three conceptual errors that are trivially refuted, with 20-30 year old sources, no less.
- His naive expectation that there’d be a one-to-one correspondence between cranial nerves and pharyngeal arches is mistaken. We don’t see such a thing, nor do we expect such a thing.
- He has the homologies of the pharyngeal arch derivatives out of register. Cranial nerve V does not innervate the first gill, and evolutionary homologies would predict that it shouldn’t innervate the gill.
- If he thinks the anatomical and functional correlations of the cranial nerves between fish and tetrapods support a creationist model, well, then he should be persuaded otherwise. They line up very, very well, and reflect common descent.