If general predators with sigmoid behavioral responses are present in the environment, it is possible for prey populations to have R-functions with three (or more) equilibrium points:

1. A low-density stabilizing equilibrium (J) created by the switching and/or aggregation of general predators in response to increases in the density of prey. Here the R-function has a negative slope indicating the dominance of ^-feedback (see figure).
2. An unstable escape threshold (E) created by predator satiation. Over this density range the R-function has a positive slope because ⁺feedback dominates and no limiting factors are encountered.
3. A stabilizing high-density carrying capacity (K) created by intraspecific competition for limiting resources. Here the R-function once again has a negative slope because ^-feedback caused by competition for a different limiting factor resumes dominance. This can give rise to an R-function with two stable (J and K) and one unstable (E) equilibrium point (see figure).

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