The purpose of this paper is to discuss the Daisyworld “parable” advanced by James Lovelock to account for the origin of global homeostasis, and to relate it to another type of model advanced in a physiological context.
The relevance of the Daisyworld model is examined in more detail than in an earlier discussion, and the relationship to physiological rein control is considered.
Both types of model exhibit effective and robust control and there is good reason to believe they usefully model forms of biological regulation.
There are implications for theories of global homeostasis and for physiology. A computer program modelling Daisyworld is made available.
The Javascript program that can be accessed online is new, though based on the earlier work of Lovelock and Watson. Much of the treatment depends on the work of Saunders et al.
