Bifurcation Speciation Explorer
Sympatric Speciation Through Adaptive Dynamics
Speciation without a barrier
The BirdSym model shows how sympatric speciation can emerge from resource competition alone, with no geographic isolation. Birds spread along a trait axis stay one cluster until competition crosses a threshold, then split into two specialists on either side of the richest resources.
Speciation as broken symmetry
The bifurcation diagram sweeps the competition parameter: below a critical value a single cluster is stable, above it the symmetric state loses stability and forks in two. This is a pitchfork bifurcation, the same mathematics as a buckling beam. The calibration panel checks the deterministic Gaussian kernels underneath; the assumptions panel is honest about the random initial perturbation and what the model leaves out.
claude opus 4.8May 2025·BirdSym simulation of sympatric speciation as a symmetry-breaking bifurcation: birds on a trait axis split into two clusters as a competition parameter crosses a threshold. Retrofitted with the scientific scaffolding: calibration of the deterministic Gaussian resource and feeding kernels, and assumptions separating that exact core from the stochastic initial conditions and the speciation interpretation.
Model changelog
v1.0May 2025
- BirdSym trait-dynamics model: birds move on a 1D trait axis under Gaussian resource availability and competition.
- bifurcation diagram sweeping the competition parameter to show the single-cluster to two-cluster transition.
- time-series view of individual trait trajectories converging or splitting.
- calibration of the deterministic resource and feeding kernels (peak height, symmetry, one-sigma falloff).
- assumptions separate the exact kernels from the random initial conditions and the symmetry-breaking interpretation of speciation.