Daisyworld: Interactive On-line PC and Mac
and is replicated here as part of the SERC Pedagogic Service.
Summary
The following is a direct excerpt from University of Wales model description. "The Daisy World model is intended to illustrate a mechanism through which - according to the Gaian hypothesis - biota might optimize their abiotic environment by means of negative feedback. The model does not attempt to describe all of the possible mechanisms and feedbacks which might influence the ways in which the plants and climate develop. Instead, it is an heuristic model - one that seeks to describe the ways in which this mechanism might work. The original model was developed by Watson and Lovelock (1983)."
Learning Goals
- Explore the concept of homeostasis in Daisy World;
- Use Excel to graph and analyze results from Daisy World simulations
- Global temperature vs Solar luminosity for Daisy World;
- Area of Black and White daisies vs. Solar Luminosity
- Area of Black and White daisies vs. average planetary temperature
- Planetary Albedo on the Y axis vs. Solar Luminosity L on the X- axis
- In their own words describe how Daisy growth on Daisy World results in homeostasis;
- Compare and contrast Daisy World to a dead planet (no daisies);
Context for Use
Description and Teaching Materials
More on Daisy World: a feedback perspective.
See also the resources below.
Teaching Notes and Tips
This JAVA activity works best on a PC but it has also worked on Macs (OS 10.2) and Mozilla Browser. Sometimes the reload button had to be used on the Mac.
Assessment
References and Resources
The Daisy World JAVA Model and PDF Activity (more info)
More on Daisy World: a feedback perspective.
Sea Floor Spreading I or World Population Activity I are good introductory lessons on how to use Excel and how to make graphs with Excel.
Another good reference for students is: Resources Graphing Tutorial: Graphing with Excel (more info) . Basics: Data input into cells, Creating a scatter plot and line graph. Advanced: Bar graphs and histograms, Importing text files, Final formatting, Regression lines, Superimposing graphs, Descriptive statistics, Selecting data for display.
A slide show discussion of Daisy World by Mike Barnsley (more info) of the Department of Geography, University of Wales Swansea, Singleton Park, Swansea, SA2 8PP.
JAVA Daisy World by Ginger Booth (more info) This is a great Flash application which gives students huge flexibility in manipulating input and output. JAVA simulations are also available from the web page. Questions and homework come with this activity.
Andrew Ford's Daisy World Flight Simulator (more info) This is a Stella Model flight simulator based on chapter 21 of Fords Modeling the Environment book
Dave Bice's Daisy World Using Stella. ( This site may be offline. ) Dave has developed a great Stella modeling activity here. Students build the Stella model by following clear instructions and then use it to perform experiments on the behavior of Daisyworld. The Basic equations are identical to those used in the JAVA Daisy World Model (which are also the equations described at the University of Wales Swansea site).