Because if you actually look at experimental results, there’s no reason to think that one can modify fundamentally the form of life by changing DNA. Mutations definitely have effects and there are some organisms that have been studied so exhaustively we really know all the effects that mutations have. The poor fruit fly drosophila melanogaster is one of these that’s been studied for many years in laboratories and mutations have been cataloged ad infinitum. And they do all kinds of horrible things to these fruit flies. Many of them do nothing, some of them kill the fruit fly and some of them deform the fruit fly. You can get fruit flies that have no wings or that have legs coming out of their head instead of antennae. All kinds of things that aren’t normal. None of them turn the fruit fly into something else. It’s a gross mutant fruit fly, it’s a dead fruit fly or it’s a normal fruit fly. There are no contrary examples. There are no examples where you can convert one life form into another by changing the DNA.