Two identical landscapes run in parallel from the same starting populations. In the left, isolated landscape, each habitat patch is cut off — its animals breed only among themselves. In the right, corridor-linked landscape, thin strips of connecting habitat let individuals actually cross between neighbouring patches.
Every generation, each patch's population grows toward its carrying capacity and its genetic diversity slowly erodes — the smaller the population, the faster diversity is lost to drift and inbreeding. Where a corridor exists, migrants moving between patches mix gene pools, propping up diversity on both ends of the crossing.
Trigger a disaster and the same patch is wiped out in both landscapes at once. With no corridor, that patch has no way to be repopulated — it stays empty forever. With a corridor, a lucky trickle of migrants from a healthy neighbour can recolonize it before it disappears from the record for good.
- Habitat patches — how many isolated fragments the original habitat was carved into.
- Corridor migration rate — how readily animals move along a corridor when one exists; only affects the right-hand landscape.
- Auto-disasters — toggle random local extinction events on a timer, or trigger one manually to compare outcomes on demand.