Two molecular species diffuse in a 2D domain with reflective boundaries. Species A (red) has a high diffusion coefficient (D=3.0) while species B (blue) diffuses slowly (D=0.3). Starting from a concentrated cluster in the center, this demonstrates how diffusion rate governs spatial spreading. No reactions occur -- total molecule counts are conserved.
Species2
Reactions0
Initial Molecules600
Final Molecules600
Snapshots61
Runtime7.92s
Particle Viewer
Species Dynamics
A classic predator-prey model with three reactions: prey reproduction (A -> A + A), predation (A + B -> B + B), and predator death (B -> 0). In a well-mixed system these produce sustained oscillations; in this spatial version, stochastic fluctuations and diffusion create complex spatiotemporal patterns. Prey (green) and predators (red) chase each other across the domain.
Species2
Reactions3
Initial Molecules600
Final Molecules131
Snapshots61
Runtime11.29s
Particle Viewer
Species Dynamics
An enzyme (E, purple) binds substrate (S, blue) to form a complex (ES, orange), which then releases product (P, green). The reversible binding step (E + S <-> ES) with forward rate k_f and backward rate k_b, followed by irreversible catalysis (ES -> E + P), produces classic Michaelis-Menten kinetics. In this spatial model, diffusion-limited encounters between enzyme and substrate create local depletion zones.
Species4
Reactions2
Initial Molecules550
Final Molecules547
Snapshots61
Runtime7.68s
Particle Viewer
Species Dynamics
A spatial rock-paper-scissors system where three species compete cyclically: Rock (red) beats Scissors (blue), Scissors beats Paper (green), and Paper beats Rock. Each species reproduces slowly and is regulated by density-dependent crowding death. Starting from spatially segregated populations (thirds of the domain), the species mix through diffusion and competition. Periodic boundaries allow populations to chase each other in cycles. This models biodiversity maintenance through intransitive competition -- a key mechanism in microbial ecology.
Species3
Reactions9
Initial Molecules750
Final Molecules342
Snapshots61
Runtime4.59s
Particle Viewer
Species Dynamics
