



Observe: Kill off most of the hawks using the – button, and then click Play. Observe the GRAPH for about 12 months, and then click Pause. What happens?
Experiment: Click Reset. Try making other changes to the ecosystem. Use the + or – buttons, or choose Diseased from the dropdown lists. Click Play and observe for at least 12 months. Record what happens below.
Summarize: Give at least one example of each of the following:
A major disturbance that the ecosystem was able to recover completely from.
A major disturbance that caused the ecosystem to stabilize at a new equilibrium.
Which organism is a producer in this food chain?
Where does the producer get its energy?
Consumers must eat other organisms for energy. Which organisms are consumers in this food chain?
Hawks
Snakes
Rabbits
Grass
What do you notice about each population as time goes by?
Notice the populations decrease as you go from the bottom of the food chain to the top. Whydo you think this is so?
Form hypothesis: How do you think predator and prey populations affect one another?
Doubling rabbit population : Grass
Doubling rabbit population: Snakes
Doubling rabbit population Hawks
Halving rabbit population: Grass
Halving rabbit population: Snakes
Halving rabbit population: Hawks
How did doubling the rabbit population affect the grass, snakes, and hawks at first?
How did halving the rabbit population affect the grass, snakes, and hawks at first?
Doubling snake population
Doubling snake population
Doubling snake population
Halving snake population: Grass
Halving snake population: Rabbits
Halving snake population: Hawks
Doubling hawk population: Grass
Doubling hawk population: Rabbits
Doubling hawk population: Snakes
Halving hawk population
Halving hawk population
Halving hawk population
How did increasing the snakes affect the grass?
Explain why:
How did increasing the hawks affect the rabbits?
Explain why:
Draw conclusions: In general, what effect did removing prey have on predators?
What effect did removing predators have on prey?
A major disturbance that caused the ecosystem to completely collapse.