Even at a molecular level there can be 'mutation' and selection. Such 'evolutionary' processes need not depend on the existence of 'life'.
MikeBGene: After life exists, you seem to be saying that both the intervention
of an intelligent agent and natural selection can explain similar
attributes. Your argument then boils down to 'we can't be sure.'
Of course not, science is never 'sure' but the lack of any evidence supporting an intelligent agent, the vaste amounts of evidence supporting natural selection as a likely mechanism and the Occam Razor surely seem to support natural selection. It's clear that NO evidence of an intelligent agent exists. SO at least that one has been eliminated as far as science is concerned. Now the question remains: Is natural selection (one of) the processes?