No one will argue that math is not a very reliable way of dealing with numbers; our modern world depends on it, and even animals can use it. Science, likewise is a very reliable way of finding information about our world, because it has proved its reliability time and time again. All of our modern technology is the result of science, and one doesn't require any faith to understand its brilliance.
Furthermore, no atheist justifies evolution by saying it is true because "Darwin says so." I have debated with theists whose last resort at reasoning is to say "because the Bible says so" or "because the Qur'an says so." The idea that a supposed "holy" book merely saying something in and of itself makes an assertion true, without any credible evidence to back it up, is reasoning gone bankrupt. That is faith, plain and simple.
Now science cannot explain each and every aspect of our universe and it might be impossible for our body of knowledge to contain everything that there is to know. Theists jump on this and assert the hand of god where there is a gap in our knowledge. And if that gap is ever closed, they then have two gaps that they fill with the hand of god. The god of the gaps method is a very weak way to assert the existence of any deity. It is best that theists simply do what they do best, which is to maintain that believing in god is a matter of faith.
"Faith means making a virtue out of not thinking. It’s nothing to brag about. And those who preach faith, and enable and elevate it are intellectual slaveholders, keeping mankind in a bondage to fantasy and nonsense that has spawned and justified so much lunacy and destruction. Religion is dangerous because it allows human beings who don’t have all the answers to think that they do."
"Where there is evidence, no one speaks of 'faith'. We do not speak of faith that two and two are four or that the earth is round. We only speak of faith when we wish to substitute emotion for evidence."