Fundamentalist Christians object to the theory of evolution because it conflicts with their interpretation of the Bible. Although this is pathetic, it is understandable to a certain extent. When one's worldview is threatened, the default response is to defend it (unfortunately, Christians defend their worldview in spite of overwhelming, undeniable evidence, but that's another topic altogether). The one thing that puzzles me is the almost unanimous objection amongst fundamentalist and conservative Christians to the science behind climate change. What's their angle, exactly?
First of all, you are believing a falsehood. Most Christians believe evolution is one of God's many tools, they simply don't object to it. The scientist who mapped the human genome is a Christian, and he doesn't dispute the theory of evolution. The most important thing for you to remember here is, evolution doesn't explain or even attempt to explain the origins of life itself. You are the simple-minded neophyte who thinks evolution displaces creationism. There is not even a basis in the theory of evolution, by which it can explain origin. Even if it is absolutely 100% established fact and law of the universe, it only makes the question of "ORIGIN" more perplexing. It does NOT refute or contradict a theory that our universe and existence may ultimately be the result of an 'intelligent' design. As a matter of fact, the very aspect of evolution would indicate an even stronger possibility that some intelligent force is in play. Remember, "Science" does not say "Just Because!" Therefore, it is an insufficient argument to have in a scientific perspective. Evolution didn't happen "just because" so the things that made evolution a possibility, also didn't happen "just because," and we've not answered those questions.
In science, there is really no such thing as "undeniable evidence" because everything can be questioned unless it is proven, and science doesn't prove, it suggests probability. Certain universal principles have been established as laws, but evolution is not really one of those. Some things have evolved rapidly, while other things show no sign of apparent evolution over hundreds of thousands of years. We can observe signs of evolution within a 'genus' but we have little or no evidence of cross-genus evolution. While the theory of evolution can explain how certain animals evolved over time to adapt to circumstance, it can't explain the rather wide array of life forms which have absolutely nothing to do with each other in how their particular systems of life operate, and in many cases, are interdependent on other life forms to even exist. Evolution has no explanation for this.
There is a theory called "Abiogenesis" which posits that all life ultimately emerged from a single cell. Okay... still... let's ASSUME this is true... where/why/how/who was responsible for that single cell? If it was some magical mystical result of chemicals and reactions of heat and water... it sounds a LOT like a specifically controlled science project of an intelligent entity, doesn't it? How would even THIS disprove the existence of an intelligent force we can't comprehend? It doesn't, it can't, and you can bang your head against a brick wall trying, it won't ever.
You can't use science to defeat faith any more than you can use faith to defeat science. You can cling to your "undeniable evidence" but be aware, Christians believe in their own "undeniable evidence" as well. So it's best we put spiritual faith and scientific faith in separate boxes, and not try to fight them against each other. It's pointless, because Science is totally inadequate to deal with matters of spirituality.