Survival of the fittest

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"Survival of the fittest", also called "the law of the jungle", (PROSE: Parasite) was a concept, sometimes related to evolution, which stated that the strongest or most intelligent of organisms survive over others in their environment. It was more scientifically known as natural selection. (HOMEVID: Unnatural Selection)

The mechanism was thought up by Alfred Russel Wallace in a dream long before Charles Darwin did, but history largely forgot him. (HOMEVID: Unnatural Selection)

Captain Cook strongly believed the ideology of survival of the fittest, (TV: The Greatest Show in the Galaxy) as did Paterson, (TV: Survival) and the Vardans, who believed in survival of the "very fittest." (PROSE: No Future)

Jane Page believed in survival of the fittest, but Qxeleq told her the Mind called it "survival of the luckiest." (PROSE: Falls the Shadow)

According to the Seventh Doctor, warrior races were an outgrowth of a survival of the fittest mentality. (PROSE: First Frontier)