The evolution and common ancestry of all living and extinct species resulting from gradual evolutionary mechanisms such as natural selection
Theory of the evolutionary mechanism proposed by Charles Darwin as an explanation of organic change. It denotes Darwin's specific view of how evolution works. Darwin developed the concept that evolution is brought about by the interplay of three principles: variation (present in all forms of life), heredity (the force that transmits similar organic form from one generation to another), and the struggle for existence (which determines the variations that will be advantageous in a given environment, thus altering the species through selective reproduction). Present knowledge of the genetic basis of inheritance has contributed to scientists' understanding of the mechanisms behind Darwin's ideas, in a theory known as neo-Darwinism