Cause it's the big enchilada. Physics is good for building stuff, and chemistry is good for blowing stuff up; but evolution is teaching us what it is to be us. The creationists (at least the heads of the Evil Creationist Conspiracy) know what this is going to mean in a decade or two. We're gonna know what makes an animal an animal, and a man a man; and it ain't go well for "Creator God." We're gonna know why the brain does what it does, we're gonna know how mind evolves from brain, and we're gonna know just where religious experience comes from in the mind.
Creationists aren't worried about god; they're worried about themselves, and their "special place." Unfortunately (as outhouse is quick to point out
), they usually have ingrained patterns of understanding that make them believe theory of evolution is undermining that special place - and they're not hearing that kinda talk. They don't realize, that if they let go of the pastor's dogma (because Creationism is in no way Biblical) and open up to the idea that all this stuff - makes god far more wondrous. This is conductor god of the cosmic symphony, standing nearly fourteen billion years behind the curtain, reaching out with the baton to tingle quantum fields - into you. That everything that has come before, had to come before; so that you could stand here, and listen to the orchestra play. The fires of emergence from cosmic vibration; the clash of titans as stars collide, live and die. And live again so that their cinders could lay the foundational blocks of carbon in your cells. Could be the iron to be mined by the hands that learned, from the minds that reasoned, to the plans once written. To the empires that had to rise and fall so that you could stand after it all, with these tools all of us had made while making ourselves... to be just what it is that can stand here and look into the eye of god.
That's evolution.