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Breeding Belyaev's Pets

Domestication, Evolution, and the Farm-Fox Experiment


J. Phil Gibson
Department of Biology and Department of Microbiology & Plant Biology
University of Oklahoma


This clicker case addresses several important concepts related to evolution. First, it explores artificial selection and selective breeding. Charles Darwin used artificial selection as an example to support his Theory of Evolution by Natural Selection. Belyaev's Fox-Farm experiment is used as an example of a study that used selective breeding as the primary experimental procedure to investigate changes in a lineage. Second, it addresses an interesting observation made by Charles Darwin in The Origin of Species in which he noted how domesticated species also show interesting traits such as drooping ears which seem to be common in domesticated species. The "Farm-Fox Experiment" not only demonstrates how a research team can thoroughly investigate an intriguing question, but also serves as a classic example of elegant experimental design. Designed for use in a large introductory-level biology class, this case study would also be appropriate for smaller classes as well as for upper-level evolution courses.


  • Describe artificial selection and how it relates to domestication.
  • Explain how artificial selection relates to and supports Darwin's theory of evolution by natural selection.
  • Explain how selection can drive genetic changes in lineages.
  • Understand how genetic variation, inheritance, and selection can result in phenotypic changes and adaptation in a lineage or population over time.
  • Understand that selection on one trait can lead to changes in other traits.
  • Develop hypotheses to investigate an identified question.
  • Predict outcomes of experiments.
  • Analyze data and interpret experimental results in light of research results.
  • Synthesize results from different studies and evaluate their larger significance.


Canines; canid; dogs; foxes; evolution; artificial selection; domestication; selective breeding; Dmitri Belyaev; Charles Darwin

Topical Areas


Educational Level

High school, Undergraduate lower division, Undergraduate upper division


PDF, PowerPoint

Type / Methods

Clicker, Interrupted



Subject Headings

Evolutionary Biology  |   Zoology  |   Bioinformatics  |  

Date Posted


Teaching Notes

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Supplemental Materials

The supplemental material below may be used in conjunction with this case study.

  Click-and-Learn: Natural and Artificial Selection hhmi/

Answer Key

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JJ Newman Rode
Pioneer Jr/Sr High School
West Lafayette
This looks great. I can't wait to use it with my AP students this year!