The theory of evolution is essentially based on two observations: (1) that all living things are involved in a struggle for survival; and (2) that all living things can pass on their characteristics to their offspring. It relies upon the combined operation of two processes generally referred to as natural selection and genetic mutation. | The theory of evolution is essentially based on two observations: (1) that all living things are involved in a struggle for survival; and (2) that all living things can pass on their characteristics to their offspring. It relies upon the combined operation of two processes generally referred to as natural selection and genetic mutation. |