KEY CONCEPT Food chains and food webs model the flow of energy in an ecosystem.

A food chain is a model that shows a sequence of feeding relationships. A food chain follows the connection between one producer and a single chain of consumers within an ecosystem. DESERT COTTONTAIL GRAMA GRASS HARRIS’S HAWK

A food web emphasizes complicated feeding relationships and energy flow in an ecosystem.

Consumers are not all alike. Herbivores eat only plants. Ex: grasshopper Carnivores eat only animals. Ex: Lion Omnivores eat both plants and animals. Ex: Bears Detritivores eat dead organic matter. Ex: Worms, slugs Decomposers are detritivores that break down organic or dead matter into simpler compounds. Ex: bacteria, Fungi decomposer carnivore

Specialists are consumers that primarily eat one specific organism (they only eat one thing) Ex: Bamboo is 99% of a panda’s diet Generalists are consumers that have a varying diet (they eat a lot of different things) Ex: Gray wolf eats elk, moose, deer, and mice

Trophic levels are the nourishment levels in a food chain.

Carnivores that eat carnivores Ex: Hawk eating rabbit ENERGY Carnivores that eat herbivores Ex: Rabbit eating grasshopper Herbivores that eat producers Ex: grasshopper eating grass

Omnivores, such as humans that eat both plants and animals, may be listed at different trophic levels in different food chains. If you are eating a salad you are….? a primary consumer (omnivore eating a producer) If you are eating a hamburger you are….? a secondary consumer (omnivore eating a herbivore) If you are eating shark soup, you are….? a tertiary consumer (omnivore eating a carnivore)