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Ecologists study how animals and plants interact with one another in their natural setting, or ecosystem. Homeostasis is the balance in the number of plants and animals in an ecosystem. When the different plants and animals compete for food, water, light, and other resources, they help to keep the balance. Sometimes natural events (like very cold weather) or man-made events (like the cutting of trees) can disturb this natural balance.

Directions: Pretend that you and the members of your group are ecologists. Read each description. Brainstorm and list the possible effects the events taking place in the ecosystem could have on its homeostasis. Then list ways to help keep the balance in each ecosystem.

Ecosystem 1
Rabbits eat the plants that grow in a large meadow. Foxes eat the rabbits. Last year the weather was so good that there were many plants. Also, many more rabbits than usual were born. Since there were more rabbits, the foxes had much to eat and stayed healthy. The healthy fox population had many more kits than usual so their population grew even larger.
Effects on Homeostasis / Ways to Keep the Balance
Ecosystem 2
In the tropical forests, people and animals have lived together with nature for many years. Lately companies have been buying the land. The companies cut down the trees for wood, or they use the cleared land for farmland. The farmland provides another source of income for the companies.
Effects on Homeostasis / Ways to Keep the Balance
Ecosystem 3
On a plateau, deer feed mostly on a small supply of grass. Coyotes feed on the deer. Hunters have been killing so many coyotes that very few remain.
Effects on Homeostasis / Ways to Keep the Balance

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