Category: Ecology

Summary: Testing whether intermediate switching periods in patch asymmetry best support cross-feeding coexistence in a two-patch chemostat.

Cross-feeding can stabilize microbial coexistence, but only if the resource gradients that support it persist long enough to matter. This experiment studies two coupled chemostat patches with a primary substrate and a secreted metabolite, then asks whether periodically switching patch-level asymmetry creates a best intermediate timescale for coexistence.

The model varies the switching period while keeping substrate and metabolite transport distinct, so that one resource mixes faster than the other. It then tracks whether slow switching traps one species in the wrong patch and whether very rapid switching washes out the niche contrast before the cross-feeding loop can build.

That focuses on temporal habitat structure rather than static coexistence conditions. The experiment tests whether coexistence is maximized by a rhythm that matches the ecological build-up time of cross-feeding.

Method: Deterministic two-patch chemostat simulations sweeping switching period and metabolite-retention conditions.

What is measured: Coexistence outcomes, dependence on switching period, substrate versus metabolite transport effects, and support for an intermediate best regime.