STRUCTURE OF FOOD WEBS

For nonrandom models of species interaction there is a precipitous decrease in stability as connectance increases. However, the range of stability for different models of the same connectance is large; stability also depends on how the species interactions are organized. Systems with species feeding on more than one trophic level (omnivores) are likely to be unstable, the extent depending on the number and position of the omnivores. For systems of equal connectance, those that are completely compartmentalized are less likely to be stable than those that are not. © 1979.