I don't think Rhabbi was denying evolution, (I mean, who would except a couple of crazed loons in turbans in the desert biting the Koran). I think he was just trying to be clever. Kind of like, evolution is just a theory and so is the existance of the supernatural. But the annalogy is a bit skewed off-course becuase evolution is suported by millions and billions and billions of evidence, each indipendantly verifiable. So it's not a very good theory to make fun of. If he would have gone with "string-theory" or something else that is high level science and philosophy at the same time, it might have gotten interesting.