most evolutionary scientists thing. It's by far the most common theory. http://en.wikipedia.org/wiki/Origin_of_life Abiogenesis (pronounced /ˌeɪbaɪ.ɵˈdʒɛnɨsɪs/ ay-by-oh-jen-ə-siss ) or biopoiesis is the study of how biological life could arise from inorganic matter through natural processes. In particular, the term usually refers to the processes by which life on Earth may have arisen.