There is no confusion about whether or not atheism is a religion. Everyone knows that atheism is not a religion, and everyone knows that atheism is a belief system.
As for evolution...
I'm sorry, but there is no experiment you can do today to absolutely prove beyond all doubt that something happened in the past.
Mathematics is based on axioms. The only reason that 1+1=2 is because we say so; humans have invented these symbols and defined their meanings, and the only people who can accept 1+1=2 are those who accept these man-made abstractions.
Evolutionary theory is the theory that explains how life changes over time. This can be represented easily by more axioms.
1) Living beings tend to reproduce.
a) In reproducing, they pass down genetic traits that they themselves carry.
2) Sexual reproduction or other conditions may cause genetic traits to be substituted, deleted, added onto, or otherwise changed based on mainly mutations.
3) These mutations provide diversity from the original pattern of genetic traits.
Based on all this, we can follow that as living beings reproduce and pass on their traits, these traits DO NOT STAY THE SAME. In other words, they change. This is sufficient to prove the theory of evolution. Just not ancestral evolution... That takes more records, such as fossils.
I'm sorry, but I'm pretty sure you missed my point. What makes mathematical axioms so absolute is that they are
designed to be absolute. Thus, anything based on these axioms can
easily be rejected as circular. Mathematical statements have absolutely
no inherent meaning,
unless they are
artificially applied to a real-life situation. However, even then, most mathematical statements are not
exactly applicable without extremely specific modifications.
The theory of evolution, on the other hand, is different because all the evidence
comes from the world itself. These "axioms", as you call them, are merely small-scale observations made in the present day. Sure, these observations
suggest that, ceteris parabus, all these mechanisms were in play in the past, and from that
suggest that evolution occurred continuously within the incomprehensibly long time between the first organism and Homo sapiens. However, simply because these observations were not
designed to be absolute, the conclusions reached from them also
cannot be absolute. And, as implied before, if they
were designed to be absolute, then they would have no meaning.