Microorganisms experience DNA changes that lead to the formation of new organisms, with the more advantageous mutations surviving while less fit ones perish. While some mutations are attributed to radioactive elements, this is not the primary source of genetic variation. Other mechanisms, such as recombination, viral interference, and copying errors, play significant roles in genetic change. Additionally, not all mutations contribute positively to selection; some, like missense mutations and certain point mutations, may not result in any phenotypic changes. The discussion emphasizes that variation is only part of the evolutionary process, with natural selection being the other critical component.
