Introduction to Interactions

 

STUDENTS WILL BE ABLE TO:
- Identify types of symbiotic relationships: competition, cooperation, predator/prey, commensalism.
- Find examples of these relationships in their local ecosystem.
- Present findings to class.

GUIDING QUESTION: How do things in our ecosystem affect and interact with one another?

CLASS ACTIVITIES:
Day 1: Wonder
1. Explain to your students that interactions can be broken down based on whether they have a positive, negative, or neutral effect on each involved party. Divide the board into four sections, marked as follows: +/-, -/-, +/+, and +/o.
2. Ask students to think of an example of each type of interaction in their home, school, or community. Let students go up to the board and write their examples in each section.
3. Introduce and define types of symbiotic relationships, putting the appropriate titles onto each section of the board:

• +/-: predator/prey
• -/-: competition
• +/+: cooperation
• +/o: commensalism

4. When defining each term, have students identify examples of each sort of relationship in their local ecosystem.
Alternative: Instead of starting with the four sections, students could first create a list of common interactions in their school/community, and then break them down into groups after teacher has defined the terms.

Days 2-4: Explore, Identify, and Organize
1. Assign each student an animal from the local ecosystem. (It is helpful to provide a list for students to pick from.) Using books and internet, identify:

• One specific animal or plant that your animal eats
• One specific animal that your animal competes with
  
• One animal that preys on, parasitizes, or decomposes your animal

2. Students should print or draw a picture of each organism. Post pictures on murals and have students use yarn to connect organisms, using different colors of yarn for each type of interaction.

Day 5: Share
1. Students should present findings, explaining what they connected on the murals and why.
2. Optional: Allow students to find additional interactions between the organisms that they found and those posted by other students. Add yarn identifying those interactions.
3. Discuss: Can any organism live in isolation from all other living things?