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gradualism vs. punctuated equilibrium

[graj-oo-uh-liz-uhm] / ˈgrædʒ u əˌlɪz əm /

noun

  1. the principle or policy of achieving some goal by gradual steps rather than by drastic change.

  2. Philosophy.  a theory maintaining that two seemingly conflicting notions are not radically opposed, but are related by others partaking in varying degrees of the character of both.

  3. Biology.  a tenet in evolutionary theory maintaining that species evolve slowly and continuously over long periods of geological time.

noun

  1. Biology.  theory of, a hypothesis holding that the evolution of species proceeds in a characteristic pattern of relative stability for long periods of time interspersed with much shorter periods during which many species become extinct and new species emerge.