I also thought of Evolution versus creation as the reasons for humans to exist.
There might be more choices than just the 2 I will mention, but lets look at it from this perspective.
If we are nothing more than the product of long durational unguided, blind, and mechanical processes, then we are only things with no right to have feelings and can not call our-self by a name as an character or individual.
WE are, so to say, only food to the strongest, or we are the ones that may feed on the weaker.
If so, there is no rights, and we must follow our basic instincts, deny art and culture, forget about writing and singing, copulate, leave the female to attend to the offspring, kill if need be, steal, eat, have sex, even rape if need.
This is what one does if one think there is nothing more to the Human existence.
However, when one believes in being a creation of a Creator, the factor of accountability is a given.
simple understanding between Evolution and Creation is that in the mind set of creation, one have to accept that the fellow human is also part of the Creators' work, and by damaging such a thing, will be an insult to the Creator just as willfully damaging your neighbor's car will be to him.
Therefore, to embrace the thought of Creation, one is undermining Evolutionary thought, and creating a moral knowing there will be accountability for our actions.
However, to embrace Evolution, well... why not just take what you want as does an animal?
There is anyway so many people on this earth, the sooner we thin yourself out, the better.
rape, steal, be gay, swing, whore, make whores, kill, lie, cheat!!!
Why not?
If we die, we die!
And dont tell me that Atheists have this high moral standards and somehow I need to place Atheism in a bad light.
Atheism has no morals, and people embrace atheism because of their nature.
Because of what they like to do, their vices!
Any atheist that say they adhere to some moral code, are attempting lie to them-self.
Or, accept that you are wasting your time, and go out and be the strongest.