Question

gizmo warm - up
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 a couple 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 couple more times.

1. select the data tab. select pictograph and click the tree to show the size of the tree population for the past several years.

a. how did removing deer affect the tree population?
b. why do you think this happened?

1. under choose organism, select the mushroom.

a. how did losing deer affect the mushrooms?
b. explain why this may have happened.

Explanation:

1. A. When deer are removed, the tree population may increase. Deer eat tree - related vegetation like leaves and saplings, so with no deer, less pressure is on the trees, allowing more to survive and grow.

B. This happened because deer are herbivores that consume parts of trees or compete for resources that trees need. Their removal reduces predation - like effects on trees.

1. A. Losing deer may have a negative impact on mushrooms. Mushrooms often rely on the organic matter from decaying vegetation and animal droppings. Deer contribute to the ecosystem by spreading seeds and their droppings are a source of nutrients.

B. Without deer, there is less of their contribution to the ecosystem. Their absence can disrupt the nutrient - cycling and seed - dispersal processes that mushrooms depend on for a healthy environment.

Answer:

1. A. The tree population likely increased.

B. Because deer consume tree - related resources and their removal reduces this pressure.

1. A. The mushrooms may be negatively affected.

B. Due to disruption of nutrient - cycling and seed - dispersal processes that deer contribute to.