Natural selection is a constant process in which the organisms that are better adapted to their environment have advantages, so they will survive and reproduce more than the ones that are not so adapted. Individuals among a species are naturally differentiated, and this difference creates a variability in which some will be better adapted than other. Mutations and changes can lead to even better adaptations, creating evolutionary advantages over the ones that did not change. This leads natural selection to be a mechanism of evolution, because these differencies and these better adapted individuals can cause an entire species to evolve or to diverge.