Daisyworld

Daisyworld, a computer simulation, is a hypothetical world orbiting a sun whose temperature is slowly increasing in the simulation. Daisyworld was introduced by James Lovelock and Andrew Watson to illustrate the plausibility of the Gaia hypothesis in a paper published in 1983.




In Daisyworld, a planet orbits a star whose energy output is slowly and steadily increasing over time. This world has two life forms—white daisies and black daisies—which grow upon its surface.



The black daisies absorb solar energy efficiently, being black, while the white daisies reflect solar energy efficiently. At the beginning of the simulation, the global temperature is so cold that only black daisies can absorb enough heat to survive.



Increased numbers of black daisies cause the temperature to rise, at which point the reflective white daisies can survive and compete.




At some point an equilibrium of temperature arises, wherein the shifting daisy populations are able to maintain a static temperature in spite of increasing solar energy.

Eventually, near the end of the simulation, the heat overwhelms the entire population and life dies out.

The really interesting thing about Daisyworld is that, in later, more complex, and more realistic models, when higher-level species such as foxes and rabbits were introduced to create elementary food chains, the ability of Daisyworld to maintain equilibrium increased. In fact, the more species that were added to the world, the better Daisyworld seemed to be able to regulate its temperature! These findings were very important in the development of an understanding that biodiversity is important to planetary ecology. Species compete brutally at an individual level, but nevertheless all share a very real interest in the proliferation of new species which will in turn have to compete with them. more

Mostly quoted from a short description of the Daisy world and the Gaia Hypotheses by Curt Lindsay who´s conclusion can be best summarized in a t-shirt by Tammy:

Good Planets are Hard to Find

Click any pic for a neat flash demonstration of the Daisy World

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