1. Evolution as such. This is the theory that the world is not constant or recently created nor perpetually cycling, but rather is steadily changing, and that organisms are transformed in time. 2. Common descent. This is the theory that every group of organisms descended from a common ancestor, and that all groups of organisms, including animals, plants, and microorganisms, ultimately go back to a single origin of life on earth. 3. Multiplication of species. This theory explains the origin of the enormous organic diversity. It postulates that species multiply, either by splitting into daughter species or by "budding", that is, by the establishment of geographically isloated founder populations that evolve into new species. 4. Gradualism. According to this theory, evolutionary change takes place through the gradual change of populations and not by the sudden (saltational) production of new individuals that represent a new type. 5. Natural selection. According to this theory, ...
Darwin postulates a creator which seeds the universe with few simple forms and some laws, and then, like a cellular automaton, 'endless forms most beautiful and most wonderful have been, and are being evolved.'