Theory of Evolution: Descent with Modification by Natural Selection
- Charles darwin used this theory
- more offspring are produced than can possibly survive in nature
- there is a "struggle to survive" among the offspring
- there are variations in all traits in every population
- offspring with variations that make them better adapted to their environment are more likely to survive, thus survival of the fittest
- offspring who survive will mate with others, who possess the favorable trait and that trait will be passed on to future generations; therefore natural selection occurs
- three basic concepts: Genes mutate, individuals are selected, and populations evolve
- which is why there are different levels at which changes are taking place; the gene level, the individual level, and the population level