This Dryad package contains source code for generating schematic figures that illustrate equilibrium geometry in a family of ecological/population-dynamics models. The scripts focus on (i) a logistic growth model and (ii) consumer–resource / predator–prey extensions with Type I and Type II (Holling) functional responses. Across alternative assumptions about the relationship between intrinsic growth rate (r) and carrying capacity (K) (i.e., different r–K relationships or trade-offs), the code computes equilibrium conditions and visualizes how equilibrium solutions lie on, or are constrained by, characteristic ellipses in parameter/state space.

The archive is code-only and does not include empirical datasets; no simulated datasets are required for reuse. Running the scripts reproduces the conceptual diagrams by deterministically evaluating equilibrium expressions and/or numerical solutions on user-specified parameter grids, and outputs publication-ready figures (e.g., PDF/PNG) along with intermediate objects (e.g., coordinates of ellipses and equilibrium points) when enabled.

Reuse potential includes (a) reproducing or adapting schematic figures for manuscripts, theses, and teaching materials, (b) extending to alternative functional responses or additional biological processes, and (c) sensitivity exploration of how assumed r–K relationships reshape equilibrium structure. The package contains no personal, sensitive, or confidential information and raises no human- or animal-subject ethical concerns. Files are intended for open reuse consistent with Dryad’s licensing requirements.