Food Chain

A food chain shows how each living thing gets its food. Some animals eat plants and some animals eat other animals. For example, a simple food chain links the trees & shrubs, the giraffes (that eat trees & shrubs), and the lions (that eat the giraffes). Each link in this chain is food for the next link. A food chain always starts with plant life and ends with an animal.

1. Plants are called producers because they are able to use light energy from the Sun to produce food (sugar) from carbon dioxide and water. The process by which plants make food is called photosynthesis.
2. Animals cannot make their own food so they must eat plants and/or other animals. They are called consumers. There are three groups of consumers.
   1. Animals that eat ONLY PLANTS are called herbivores (or primary consumers).
   2. Animals that eat OTHER ANIMALS are called carnivores.
      • carnivores that eat herbivores are called secondary consumers
      • carnivores that eat other carnivores are called tertiary consumers
        e.g., killer whales in an ocean food web … phytoplankton → small fishes → seals → killer whales
3. Animals and people who eat BOTH animals and plants are called omnivores.
4. Then there are decomposers (bacteria and fungi) which feed on decaying matter. These decomposers speed up the decaying process that releases mineral salts back into the food chain for absorption by plants as nutrients.