I'm not saying that atheists can't act morally or have moral knowledge. But when I ascribe virtue to an atheist, it's as a theist who sees the atheist as conforming to objective moral values. The atheist, by contrast, has no such basis for morality. And yet all moral judgments require a basis for morality, some standard of right and wrong.
The very large brain that humans have, plus the things that go along with it - language, art, science - seemed to have evolved only once. The eye, by contrast, independently evolved 40 times. So, if you were to 'replay' evolution, the eye would almost certainly appear again, whereas the big brain probably wouldn't.