Evolution Paper Evolution according to Collins dictionary means gradual change in the characteristics of living things over successive generations, especially to a more complex form. My definition, evolution is gradual development, expansion, maturation or progress of life in different ways. Science defines evolution as the process by which species of organisms arise from earlier life forms and undergo change overtime through natural selection. The modern understanding of the origins of species is based on Greenberger (11) theories on Charles Darwin combined with a modern knowledge of genetics based on the work Gregory Mendel (Edelson 51). Evolutionary processes give rise to diversity at every level of biological organization, including species, individual organisms and molecules such as DNA and proteins. Heritable traits are known to be passed from one generation to the next via DNA, a molecule that encodes genetic information.