Survival of the fittest ; fittest or selected for means species population growth Article Talk wikipedia Language Watch Edit For other uses, see Survival of the fittest (disambiguation). "Survival of the fittest"[1] is a phrase that originated from Darwinian evolutionary theory as a way of describing the mechanism of natural selection. The biological concept of fitness is defined as reproductive success.

Charles Brown , i.e. population increase or decrease

In Darwinian terms, the phrase is best understood as "Survival of the form that will leave the most copies of itself in successive generations."

Charles Brown Exactly the Type, Genotype

Not "survival" of individuals, because all individuals are mortal , and eventually don't survive. Perpetuation of a genotype through reproductive mating producing fertile offspring ; many fertile offspring . Darwin says rarity is often a precusor to extinction .