Evolution is the product of Natural Selection AND Mutation. Either alone does nothing.

Evolution is the logical outcome of the world around us. Organisms that store their genetic information in DNA are guaranteed to have mutations. Mutation produce NEW variation. Reproducing organisms are guaranteed to compete for resources. Competition between variable organisms leads to natural selection, i.e. those organisms that possess variation that gives then an advantage will out compete those who don’t. Organisms with deleterious variation will lose to all other organisms. In this way the ENVIRONMENT SELECTS the best organisms, which has the effect of passing beneficial mutations on to the next generation and removing deleterious ones. Over time natural selection will lead to a net shift in the genome of the population, i.e. evolution.