Honolulu Zoo Society : Interdependence - What's for Lunch?


Topic Overview

Begin the Lesson

This lesson introduces the concept of a food web. Students will learn how animals and plants are interdependent on one another. Energy from the sun (producer) feeds plants (producers) who then feed consumers (herbivores, carnivores, and omnivores). Students will define, interpret and analyze the cycle of life through food webs.


Whole Class Introduction to the Lesson

You will need at least one computer with Internet connectivity and a projection device, a classroom with more than one computer, or access to a computer lab.  This introduction will take approximately 10 minutes to complete. Make and distribute index cards to your students with the following terms: producer, consumer, plant, fly, frog, snake, underwater plant, shrimp, fish, bear, and hawk. Preload the following Web site (there is an ad before the video begins): https://www.youtube.com/watch?v=KyefVtxY-oI. Review the terms on the index cards. Tell students to stand when their term is described in the video. Show the video and observe as students stand.

Sample Questions:

  • Why are plants important in a food web?
  • In the video, two animals need fish in the food web. Can you name those two animals?
  • What might happen if there were no more shrimp for the fish to eat?

Allow time for discussion of these questions. End your introduction by emphasizing the definitions of the terms producer and consumer.

As part of the introduction, you may want to review some of the glossary terms in advance of students going online. At this point you can launch the WebLesson as whole-class activity using a projection device, or you can assign students to work individually or in teams in a computer lab.



WebLesson Sites
Plants and animals depend on each other to live. Plants and animals need each other. A caterpillar depends on a wheat plant for food. Birds eat the caterpillars. Without the wheat there would be no caterpillars for the birds to eat. This is called interdependence. The interdependence of plants and animals is called a food web.
Did you have pizza for lunch today? Think about the crust of your pizza. The dough for your pizza crust was made from wheat planted by a farmer. The sun produced energy for the wheat to grow. The farmer harvested the wheat to make flour for the bread.

Other animals eat wheat as well. Caterpillars eat the wheat and birds eat the caterpillars. Think about what would happen to the wheat plants if the birds all disappeared.
Lesson Pages
The Wildlife Web 2: Herbivores and Carnivores
Bill Nye the Science Guy
Rich Media
Conclusion & Project
A food web shows all of the relationships between all of the plants and animals in a community. Cows might be food for humans or flies. Each of those flies might be food for frogs or spiders. All plants and animals need each other in a food web.

There are dozens of connections for every organism. When you draw all of those connecting lines, you get a web-like shape. This shape is what we call a food web.
Remember the flour for your pizza crust? Remember that the flour was made from wheat. Remember that caterpillars eat the wheat too and that birds eat the caterpillars. What would happen to the flour for your pizza if all the birds disappeared?
carnivore - An animal that eats plants and other animals.
consume - To eat or drink or use.
consumer - a plant or animal that gets its energy or food from other living things
decomposer - an organism, like bacteria, that breaks down dead plant or animal matter and releases their nutrients back into the soil
dependent - To need something or someone. In science, to need something in order to live.
food web - the complex network of food chains in an ecosystem
herbivore - an animal that eats only plants
interdependence - Dependent on something or someone else for your needs.
omnivore - an animal that eats plants and other animals
oxygen - The air we breathe.
predator - an animal that hunts, kills and eats other animals
prey - An animal hunted by another animal for food.
producer - a plant that produces its own food. Plants use energy from the sun to make food.
species - Types of organisms; plants and animals.
survive - To live; remain alive.
vegetation - Plants or lots of plants growing in one area.