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Lesson summary for:
Natural selection: The basics


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Darwin's most famous idea, natural selection, explains much of the diversity of life. Learn how it works, explore examples, and find out how to avoid misconceptions.
This article is located within Evolution 101.

UC Museum of Paleontology

Grade level:

30-40 minutes

Teaching tips:
This tutorial provides basic information on how natural selection works and would make an excellent introductory reading for further investigations of natural selection at work.

Correspondence to the Next Generation Science Standards is indicated in parentheses after each relevant concept. See our conceptual framework for details.

  • There is a fit between organisms and their environments, though not always a perfect fit. (LS4.C)

  • Evolution results from selection acting upon genetic variation within a population. (LS4.B)

  • Traits that confer an advantage may persist in the population and are called adaptations. (LS4.B, LS4.C)

  • Inherited characteristics affect the likelihood of an organism's survival and reproduction. (LS4.B, LS4.C)

  • Natural selection acts on the variation that exists in a population. (LS4.B, LS4.C)

  • Fitness is reproductive success - the number of viable offspring produced by an individual in comparison to other individuals in a population/species.

Teacher background:

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