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Unit 25: Evolution and the tree of life

400 possible mastery points

About this unit

This unit is part of the Biology library. Browse videos, articles, and exercises by topic.
Learn about evolution, the process in which groups of organisms change in their genetic makeup and heritable features over time. Natural selection is an important mechanism of evolution, one that can cause groups to become better suited to their environments over generations.
A family tree can tell you how you are related to your close relatives...but an evolutionary tree can tell us how all living things on Earth are related! Learn about what makes something a species, where new species come from, and how living organisms can be classified into groups (on the basis of either evolutionary relatedness or other features).
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Biology is brought to you with support from the Amgen Foundation