food chain: Quick Facts

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Photos and Videos

Illustration of an ocean food chain showing sunlight supporting one-celled life like dinoflagellates and diatoms, which are eaten by shrimplike copepods. These are consumed by small fish, which are then eaten by mackerel, followed by tuna, and finally a large shark at the top of the food web.

Diagram of a terrestrial food chain showing plants as primary producers, eaten by herbivorous mammals and insects, which are consumed by small and large predators, with decomposers like fungi, bacteria, and earthworms recycling organic matter.

Illustration comparing a complex ocean food web, with interconnected feeding relationships among marine animals and plankton, to a simple linear food chain showing energy flow from sun to producers, primary consumers, and up to top predators.

An energy pyramid diagram showing four levels: producers like grass at the base, primary consumers such as rabbits above, secondary consumers like snakes next, and a tertiary consumer, an eagle, at the top. Arrows indicate energy transfer upward and energy loss at each level.

Close-up of a spider with a yellow and black striped body sitting at the center of its web, with a blurred green background.

How an ecosystem works

Take an in-depth look at the variety of plankton, from diatoms and microflagellates to jellyfish

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Topics

food web What Purposes Do Mosquitoes Serve in Ecosystems?What do ants eat?How is honey made?What eats snakes?nutrient cycle grazing food chain trophic level Water cycle Nitrogen cycle guild biodiversity keystone species ecological succession ecotone biome niche indicator species

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Key People

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Charles Elton

English biologist