One of the principal objections to the argument from reason (AfR) is that evolution provides a sufficient explanation for our ability to think critically. Reliable cognitive faculties provide us (human beings) with a much better chance of survival. I think this is undoubtedly true, unless as Alvin Plantinga argues, there are equally advantageous ways of surviving without generally reliable cognitive faculties.
However, let's leave aside Plantinga's argument for now and just take the objection at face value. What does it truly illustrate? Well, on an evolutionary model of natural selection, we just get survival. It's not as if natural selection "cares" about whether we have cognitive faculties that are reliable well beyond what is needed for survival. Yet, as little as we know relatively speaking, we also have a vast amount of knowledge that's simply gratuitous to survival and reproduction. How exactly does knowledge of General Relativity Theory give us a survival advantage? I'm sure someone could come up with a hypothesis, ad hoc though it may seem.
In any case, the evolutionary objection to the AfR is not at all conclusive, and is at best an explanation for rationality as it relates to survival. It explains nothing more.