Using an ecosystem with which you are familiar (deciduous forest, grassland, desert, freshwater pond, etc.) draw a diagram of a food chain, using at least four organisms at different levels. Indicate in your diagram the ultimate source of energy. As much as possible, account for all of the energy as it moves through the chain

Question

What will be an ideal response?

Answer 1

Every student's answer will differ. No student should use the hummingbird example from the text. The ultimate energy source in almost all food chains is the sun. Every food chain should begin with a photosynthetic organism (plant, algae, etc.). Each food chain will probably consist of a couple of animals: first, a plant-eater (an insect, a rodent, etc.); and second, a meat-eater (a fish, a wolf, etc.). The best food chains will include a decomposer (a fungus, bacteria, etc.) that uses the energy in waste material and dead organisms. Indications of energy transfer should include the energy each organism uses to grow and maintain its body, as well as the energy dissipated with each change in energy form as heat.