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Evolution and Darwin

Terms

Common Descent - The belief that all present life evolved from a few common ancestors.

Gradualism - The Darwinian belief that evolution takes place in innumerable small steps. Led Darwin to believe that the world was much older than previously thought.

Darwinism - The theory of evolution proposed by Charles Darwin. It holds that species change over time and that this change comes about through the mechanism of natural selection.

Natural Selection - The theory holding that competition exists within species, determining which species live to have offspring, and pass their traits on to those offspring.

Population Speciation - The Darwinian belief that there are random phenotypic variations within species that confer advantages selected for by natural selection; these variations can be passed from parent to offspring.

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On the Origin of Species