Daisyworld, a computer simulation, is a hypothetical world orbiting a star whose radiant energy is slowly increasing or decreasing. It is meant to mimic important elements of the Earth-Sun system, and was introduced by James Lovelock and Andrew Watson in a paper published in 1983 to illustrate the plausibility of the Gaia hypothesis. In the original 1983 version, Daisyworld is seeded with two varieties of daisy as its only life forms: black daisies and white daisies. White petaled daisies reflect light, while black petaled daisies absorb light. The simulation tracks the two daisy populations and the surface temperature of Daisyworld as the sun's rays grow more powerful. The surface temperature of Daisyworld remains almost constant over a broad range of solar output.
Click PLAY to run the simulation, and RESET to start back at the initial conditions. The slider controls the energy output of Daisyworld's sun.
The yellow line shows the heat coming from the sun, the red line shows the planet's average surface temperature, and the white and black lines show the diasy populations. The brown line shows the deer population, if enabled.