Period Doubling route to Chaos. This is a simple mathematical equation to model population that displays complex (and very gnarly) behavior. Good values of rateofGrowth to demonstrate sensitive dependence: Time step 5, turn off erase previous and run the following values: 3.8000000 3.8000001 3.8000002 3.8000003 etc. if you want. Good values to demonstrate attractors: point: 2.9 periodic:3.2 Strange: 3.9 Credit to Steve Baedke and Lynn Fichter for the idea.