This is a common misperception of the theory of evolution. It says nothing about how life began. It merely tells of the evolution of existing life. I realize that your question may just be out of curiosity, but it is important to point out that any theory of life's beginnings is compatible with the theory of evolution. Whether it is "primordial soup", "seeding by aliens", or "devine intervention"... evolution still functions to take what we started with to produce what we have now.