I hate to keep beating on this drum, but it’s an error that many defenders of evolution make. Frederick Turner says:

…I did state flatly that the theory of evolution had been proved. I wanted it to be clear where I stood. Much of the mail I received protested about that statement. I hold to it, and hold to it not as my own opinion, but as a fact, like the existence of Australia, which is not my opinion but a fact. But I do know that there are many who sincerely, and given their range of knowledge, rationally, do not believe in the theory of evolution.

This ignores the (in my opinion, correct) position of one who believes in evolution, but doesn’t believe that it has been “proved.” This is because no scientific theory is ever “proved.” Proofs are for mathematics and the courtroom, not science. Scientific theories are useful in that they can be disproved, something that Creationism cannot.

I discussed this at length several months ago.