At least there's one professor at BYU that believes in evolution!
I understand why it might be tempting to put BYU in a basket along with the rest of the evangelical christian universities. However, on the issue of evolution it could not be more different. I graduated from there with a degree in microbiology and my college at least evolution was the coin of the realm, just like it is in any serious biology department. I did not have a single professor that did not see evolution as you might expect a biologist to see it; as the only serious explanation of the data at hand, the only theory that works with what we know and provides valid predictions of future results. Not once did I hear even the smallest bit of credibility being given to creationism or its various variants (intelligent design, etc).
And yes, my professors were all Mormons. You might ask yourself how they square this. It turns out that while there are certainly Mormons that take a very literal reading of the bible on this issue, that is not the official church position, and there are many members that don't see it that way at all. Basically I had several professors that explained it as religion was about how to live life, science was about how life works, and we really have no idea how the two come together. The bible, while providing a lot of information to believers on a moral life, provides no real information on how the world works in any of the scientific fields.
Interestingly, many believe this is on purpose, that God has no interest in proving his existence; it's a matter of faith for a reason. Because of this He stays out of offering scientific explanations. I realize that sounds distinctly like a cope-out, but frankly it leads to a fairly rational place where you can function as a scientist an still be a Mormon. And by function I don't mean some half-way hands over eyes sort of a way, but in a real, go where the evidence takes you sort of a way.
Take it for what it's worth, but that was my experience