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Unit 21: Evolution and the tree of life

About this unit

Discover the diversity of life on Earth and the forces that shape it! In this section, you can learn about evolution, natural selection, and the tree of life, as well as basic population genetics. Special bonus: take a peek into the amazing worlds of bacteria and viruses.

Evolution and natural selection

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Population genetics

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Speciation and evolutionary trees

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Biology is brought to you with support from the Amgen Foundation

AP® is a registered trademark of the College Board, which has not reviewed this resource.