Living Things in Ecosystems Every organism can be

Living Things in Ecosystems • Every organism can be classified as a producer, a consumer, or a decomposer. Scientists classify an organism into one of these groups according to its role in an ecosystems. An organism’s role includes the way it gets energy. Energy enters most ecosystems as sunlight.

Producers • Organism that make their own food are called producers. Producers capture the energy in sunlight. They use the energy to make their own food. Plants are producers. The green scum that grows on a pond is made of simple organisms that make their own food. They are producers, too. Some bacteria are producers. And so are some onecelled organisms that live in water. When producers make their own food, their energy that came from sunlight is stored in their bodies.

Consumers • Organisms that get energy by eating other organisms are call consumers. Scientists classify consumers into three groupsherbivores, carnivores, and omnivores.

Herbivores • Organisms that eat only plants and plant products are called herbivores. They get energy by eating roots, stems, leaves, flowers, fruits and even plant sap. Herbivores range in size from huge elephants to tiny insects. Gorillas, deer, cows, and rabbits are herbivores. So are grasshoppers, snails, and the caterpillars of moths and butterflies.

Carnivores • Animals that eat other animals are called carnivores. Carnivores get energy by eating the bodies of other organisms. Not all carnivores eat what you think of as meat. For example, a lady bug eats the entire body of any insect it catches. Lady bugs are carnivores. So are spiders and praying mantises.

Carnivores • Many carnivores have adaptations that make them good hunters. For example, lions have strong legs for chasing animals and sharp claws and teeth for grabbing them. They also have good eyesight, hearing, and sense of smell for locating animals to hunt. Lions’ sharp teeth let them tear apart their catch. Other examples of carnivores are sharks, hawks, hyena, killer whales, owls, and wolves.

Omnivores • Animals that eat both plants and animals are called omnivores. Bears are the largest omnivores. In the spring, Alaskan grizzly bears feed on salmon that are swimming up rivers. In the summer and fall, the grizzlies eat huge amounts of fruits and berries. Other examples of omnivores include cockroaches, crows, raccoons, coyotes, and humans.

Decomposers Some organisms don’t make their own food or eat living organisms. They feed on dead plants, and dead animals. They also feed on animal wastes. Organism that get energy by feeding on dead materials and wastes are called decomposers. Earthworms, centipedes, and pill bugs break dead leaves into tiny pieces as they feed. Decomposers also include molds, mushrooms, and bacteria. Decomposers keep an ecosystem from being overloaded with dead organisms and waste.

Food Chains All organisms need energy. The main source of energy on Earth is sunlight. Producers capture the energy in sunlight to make their own food. The plant then stores the energy. Think about a rabbit. The rabbit then eats the plant and the energy that was stored in the plant is now in the rabbit. The rabbit uses some of the energy to live and stores some of the energy. If an owl eats the rabbit, the owl now gets the energy from the rabbit. If the owl dies or produces waste, then the fungi or decomposer now receives the energy from the owl. This path of energy is called a food chain. A food chain always starts with the producer who gets energy from the sun.

Activity 1. Use the Vocabulary Word Fact Chart to define the vocabulary words: producer, consumer, and decomposer. Provide facts from the Power. Point. 2. Create a Venn diagram to compare carnivores and herbivores. 3. Draw a food chain to include the sun, producer, herbivore, carnivore, and decomposer.