There's so much evidence for both the Big Bang and evolution, it can't be ignored.
Remember, a theory isn't something that a bunch of random scientists believe on consensus. It's not like Darwin one day walked into a classroom and said...
"Hey guys! I got an idea! Slugs changed into birds over time!"
"That's awesome, Charlie! Brilliant, even! Now let's get out there find proof that supports that claim!"
...then rolled on from there until they cobbled a bunch of pieces together into a loose framework they now call evolution. For a theory to be called a theory in the scientific community, it has to be rigorously tested and repeatedly confirmed to the point that a bunch of people can say "yes, this accurately explains this phenomenon we've been observing".
Now that's not to say the theory of evolution is perfect, and the body of work we have now is the perpetually perfect example thereof. But if someone pops out a new theory of evolution some time in the future, it will have used the previous theory as its foundation, and built on it from there.
edit: I love that link...
Evolutionists often look at a characteristic of an organism and assume that it was produced through a gradual series of changes and call it an adaptation to a given environment. To an evolutionist, legs on tetrapods are an adaptation that arose as a fish’s fins became adapted to crawling in a shallow stream, providing some form of advantage. The fins with more bones were better adapted to a life partially lived on the land. Fins that developed bones attached to a pectoral girdle (another set of bones that had to develop) gave an advantage to those individuals that wandered onto land to find food or avoid predators. The problems with this scenario are in the amount of time such a change would require and the lack of a mechanism to cause the change.
Evolutionary biologists assume, based on geologic interpretations, that there have been billions of years for this process to occur. But if long ages did not exist, the hypothesis cannot be true.
I can prove beyond a shadow of a doubt that there is no such thing as cinnamon bread. Because without cinnamon, you can't have cinnamon bread. A true cinnamon bread would not need a prerequisite. It'd merely
be cinnamon bread as part of a logical whole.