Chemostat Simulation 5

In this simulation, nutrients (shown in green) flow in from the right hand side. The initial population of grazing animals is 10.

In this model, however, the offspring of each grazer has a 50% chance of being either a faster or slower reproducer. But also the nutrient energy input into the stream cycles between +/- 50% of its mean value over a 300 day period.

The result is that at the nutrient minimum, energy-expensive fast reproducers tend to die out, leaving low-energy slow (blue and black) reproducers.

The population initially falls to 5-10 grazers (they may all die out) and then gradually grows as the slow reproducers become established.