Ecosystems Curriculum

Section 5: Reinforcement Activities

Two-Way Web of Life Game

Follow the directions for the basic Web of Life game described in Section 1, Understanding the Connectedness of Ecosystems. This time, explain that instead of thinking about the transfer of energy, or who eats whom, we're interested in all the different ways that organisms in an ecosystem rely on each other. Have students give examples of ways that organisms rely on each other in ways other than for food. Some examples may include: The plants need the earthworms to make rich soil for them; The rabbits need the owls to keep the size of their populations small, otherwise there will be too many of them and not enough plants to eat and they'll starve.

This idea in particular, of the prey organisms needing the predator organisms as much as the predators need the prey, may not be intuitive for students and may need to be discussed further. Once students have a grasp on the concept, explain the goal of the game: to reverse all the 'connections' that were made during the first round of the Web of Life; that is, to show that the connections between organisms are also mutual, two-way connections.