Tragedy of The Commons

Photo credit: Dan Barbus at www.everystockphoto.com

How can we better work together to manage and care for our community resources?  What natural consequences occur over time when people act only in their own interest in the short term?  These are among the questions that ecologist Garrett Hardin described in his prescient 1968 article "Tragedy of the Commons", which provided a jumping off point for a fourth and fifth grade exploration in the Studio Lab.


Students worked in small groups, and each represented a "family" in a lakeside community.  A piece of paper stood in for the lake, and 16 goldfish crackers represented the fish living in it.  Studio Teacher, Julia Gonzales, described the scenario: Each year, each family will catch "fish" from the lake.  They need one fish for their family to survive, two fish enable them to live very comfortably, and if they caught more, they can sell them for a profit. 

Students took turns "catching" fish for the first round, which represented the first year.  At this point, they learned new information: that each fish remaining in the pond can reproduce, doubling the number that survive.

Each team then proceeded to "fish" for three more turns, or "years", and recorded their catch and fish population data on a group data sheet.

Ms. Julia led the class in a discussion of their data, and the effect that each community's choices had on the sustainability of the lake's resources.

Some individuals chose to catch the maximum number of fish at each turn, quickly depleting the lake's population of fish.  Other groups planned more carefully, ensuring that their community would thrive on an abundance of fish. 

The Tragedy of the Commons exercise uses math skills to explore themes students are learning in Social Studies, as well as their Life Science unit about ecosystems, biodiversity, organism survival, and competition in food chains.  It provides entry for ongoing discussion about environmental stewardship, global hunger and pollution, and extends students' awareness of how they might better manage their own shared resources, by re-shelving their own books in the library, for example.

For another perspective on the Tragedy of the Commons, here is a brief animated summary that you might like to check out:

If you have trouble viewing it, try this link instead: Tragedy of the Commons.

For more on Walgrove's Studio Lab Program, click here: http://publicschoolstudio.blogspot.com/p/faq.html .