We have shown that the fragmentation of species habitat has a significant influence on the homeostatic performance of the biosphere. A unique threshold can be identified, where the regulation of global temperature breaks down and ``life'' loses control of its own subsistence conditions.
The introduction of herbivores to fragmented Daisyworld generates an extremely rich eco-dynamics. For specific ranges of parameter combinations intermediate homeostatic regimes appear. Remarkably counter-intuitive effects prevail like the reduction of herbivore concentration with increasing vitality. Thus our toy model demonstrates, in a nutshell, the subtleness and vulnerability of community-environment relationships.
Future work on this subject will focus on more realistic rules for animal motion and replication. In particular, the self-restriction of herbivores by habitat fragmentation through overgrazing can be simulated (``desertification''). Another interesting option is the simulation of civilizatory habitat fragmentation by more realistic processes for urbanization and infrastructure expansion.