Charles Darwin describes nature as a result of evolution. In 1859, Darwin published On the Origin of Species. In this publication, the idea of evolution is first explored. Within this theory, Darwin introduces the idea of survival of the fittest. He believed a species’s environment naturally ensures some members of the species thrive and others perish depending on their individual traits. For example, rodents born with the same fur color as the surroundings will be more likely to hide from predators, thus making it more likely they will survive and reproduce. Rodents with contrasting fur colors will be more noticeable to predators. Thus, rodents with contrasting fur will often perish before reproducing. Eventually, the species will evolve into rodents with fur colors closer to the surrounding habitat color.