The Forest Ecosystem Gizmo shows you the effects of adding organisms to, or taking them from, a forest. An organism is any living thing. To start, do the following:
Click Advance year TWO times to see two years of growth.
Remove all Deer from the forest by clicking the minus (-) button until none remain.
Click Advance year a TWO TIMES
Select the DATA tab. Select Pictograph and click the Tree to show the size of the tree population for the past several years.
How did removing the deer affect the tree population?
Under organisms click on Mushroom. How did removing the deer affect the mushroom population?
What happened to the number of trees in the forest?
Are trees producers or consumers?
Did adding mushrooms negatively affect the tree population?
The mushrooms thrived without hurting trees. How do mushrooms get energy?
How Bears Affect the Population
Click Reset. Click Advance year a TWO times. Add as many bears to the forest as possible.
Click Advance Year FOUR Times
Select the DATA tab and click on Line Graph
What happened to the number of deer when more bears were added?
What happened to the number of trees when more bears were added?
Can the bear population survive if there are no deer in the population (try it out by removing all the deer)?
What happened to the deer population after three years? Explain why the deer population changed.