We have plenty of physical evidence for evolution. Fossil records, genetic similarities between species... and then there's just the pure logic of natural selection. Having gone to a Baptist school, I know all the ways Creationists try to bend it around and make it look false, and I can tell you, that is what fails.
I believe in evolution as well, but sometimes arguments along these lines don't really make the cut. Simply because certain animals look similar to each other, or have similar DNA doesn't mean they evolved from each other. Likewise natural selection isn't evolution. It's the various mutations that happen over time, that lead one species to evolve into a completely different animal, is what creationists dispute. Not micro evolution on a rudimentary level.