You are confusing evolution with atheism. They're totally different. A person can be either one or both or neither.
Perhaps that's because every evolutionist I've ever met (my own personal experience) has been an atheist. If there truly is a difference between the two, please explain it. True evolutionists flat-out reject a supreme being having anything to do with life on earth. Evolutionists (who really do require a leap of faith to believe what they say is true) point to a set of circumstances that "just so happened" to create life on this planet, and brush off the billions and billions of other possibilities that COULD HAVE happened without life being created. (Can you say "intelligent design" or at a minimum "intelligent intent?")
It seems to me that believing in evolution requires just as much "faith" (for lack of a better way of saying it) as believing in God does. Oh the irony in that statement.
Even Darwin at the end of his own life, had serious doubts about his own theories of evolution. Carbon dating has been shown to be terribly flawed, that is fact. The same process has been proven to date a pencil that was manufactured last week to be as old as a dinosaur that allegedly roamed the earth 65 million years ago.