The DNA record does not support the assertion that small random mutations are the main source of new and useful variations. We now know that the many different processes of variation involve well regulated cell action on DNA molecules.
Genomes merge, shrink and grow, acquire new DNA components, and modify their structures by well-documented cellular and biochemical processes. Most of the scientists referenced on this web site have come to a wide range of conclusions about different aspects of evolutionary change. Many see evolution as a complex process with distinct mechanisms and stages rather than a phenomenon explainable by a small number of principles.