FA-65764 / Ecological population dynamics / Member archive

MacArthur-Wilson island equilibrium: equilibrium richness · case 04

Predicted richness can exceed the mainland pool.

Member previewVariant 4 · 3 implementations · 7 checks per implementation

Case contract

I0 = imax*exp(-distance/d0); E0 = emax*a0/area; S* = I0*P/(I0+E0); turnover = I0*E0/(I0+E0); return [S*, turnover, I0, E0] rounded 4; None for non-positive parameters or negative distance.

Why this case matters

Population projections set harvest quotas, conservation status and pest-control timing; a wrong update order, boundary or rate conversion silently changes management advice.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
regression: near large island	`[4093.6538, 0.1907, 4.0937, 0.2]`	`[190.6839, 0.1907, 4.0937, 0.2]`	Failed

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