By John Miller and Michelle Smith
(reprinted from BugNet, the newsletter of the Montana EE Association)
Introduction
The traditional method for teaching students about ecosystems has consisted of lab specimens, worksheets, films, and lecture by the instructor. Absent from this approach are process-oriented, critical-thinking challenges along with meaningful field experience. This activity is used throughout the year as a means to introduce new concepts and to increase student motivation along with practical and critical-thinking skills. This activity facilitates the application of these skills and knowledge to solving current problems in our society.
Objectives
• Students will apply the concepts of interdependence, adaptation, and homeostasis in the manipulation of an imaginary ecosystem.
• They will then apply foundation knowledge to the evaluation of contemporary issues.
Teacher Directions
There is no one way to arrive at the individual outcome of each step in this activity. A framework for a unit and several suggested options for implementation have been listed. It is up to the instructor to determine the amount of time needed for each segment based on the level of the students. Most of all, be creative and have fun.
Materials
Butcher paper Rulers
Thermometers Markers
Scissors Tape measure
Procedure
1. Students map, measure, define and describe a specified location. Outside possibilities include a parking lot, football field or courtyard. Indoor locations include the gym, cafeteria, hallway, or aquarium. The location you choose will become the “ecosystem” the entire class will work on.
2. Have the class generate through brainstorming a list of characteristics, biotic and abiotic, of the ecosystem. The teacher may facilitate the brainstorming to achieve a complete list. Small groups may need to return to the ecosystem to substantiate observations and revise notes.
3. Individuals or small groups will discuss and prepare a written report describing the ecosystem. Each group must provide the following:
a. headline for their ecosystem article
b. written article describing the ecosystem in detail
c. detailed map of the ecosystem
d. group report presenting a, b & c
4. Each group will identify the life needs of animal species to survive in the ecosystem. The teacher may need to direct the list to include oxygen, water, food, shelter, reproduction, space, climate, adaptations, and species behavior. Let the group reach a consensus through discussion on the life needs of animals.
5. Students design, draw and assign a scientific name to an imaginary animal that lives exclusively in the ecosystem. Students will also consider the following:
a. life needs (this imaginary animal may feed on biotic or abiotic food sources)
b. behavioral and physical characteristics
The teacher may choose to introduce information on taxonomy, adaptations, and space requirements. Refer to “Fashion A Fish” from Project WILD Aquatic or “Adaptation Artistry” from Project WILD.
6. Groups present their animals to the class.
7. Have the class discuss he interrelationships among the animal species and the ecosystem. Students should consider the following:
a. competition, space, food, and water needs for each animal in the ecosystem
b. interdependence and food webs
This is a critical step. Consider concepts of predator-prey relationships, mutualism, symbiosis, parasitism, and commensalisms.
8. Have the class create a food web by pasting their animal under the appropriate category (producer, first order consumer, second order consumer, third order consumer, decomposer) on a large piece of butcher paper. Discuss the history and determining factors of classification systems. What kingdom, phylum, class, order, family, genus, and species would your “animal” be classified as?
9. Now have the class discuss population dynamics and carrying capacity. Include growth curves, limiting factors, and sampling methods.
10. the instructor should determine the population size, sex ratios, and birth and death rates. You can determine population sizes by lottery or random distribution. The teacher should consider the final outcome before assigning these numbers. Keep in mind the true distribution of animals in the food pyramid. Each student will graph the population of his/her animal species for ten years.
11. The teacher will now introduce a man-made alteration into the ecosystem that will have long-term effects suggested changes include: grazing lease on the football field, an increase or decrease in cleaning of hallways, asphalt significantly increases in value and mining takes place…
12. Have the class assess the effects through discussion. You may find students become attached to their imaginary animals and become upset when their animal gets directly affected.
13. Have each group design a species-management plan to optimize the chances of their species surviving. Make a realistic plan.
14. Have groups present their plans to the class. You could hold a full-participation public hearing to encourage balanced discussions. You can use this hearing to show the role special interest groups play in the political process.
15. Have the class decide on a single, comprehensive plan to maintain a healthy ecosystem.
Evaluation
Assessment may be done at each step in this activity according to the desired outcome specified by the teacher. Rubrics are useful tools that help students and teachers focus on the desired outcomes. As this is a year-long activity that applies and assesses knowledge gained, the cumulative comprehensive plan to maintain a healthy ecosystem and class discussions will assist in determining not only he information gained but the information retained.