Food chains

A food chain shows what eats what in a particular habitat. It shows the flow of energy and materials from one organism to the next, beginning with a producer.

In the example, grass seeds are eaten by voles, and voles are eaten by barn owls. The arrows between each organism in the chain always point in the direction of energy flow from the food to the feeder.

A food chain showing grass seed eaten by a vole which in turn is eaten by an owl.A food chain

The Sun is the ultimate source of energy for most communities of living things. Green plants are usually the producers in a food chain.

Producers are organisms that make their own organic nutrients (food) - usually using energy from sunlight. Green plants make their food by photosynthesis. The other organisms in a food chain are consumers, because they all get their energy by consuming other organisms.

OrganismHow it gets its energy
ConsumerFeeding on other organisms
Primary consumerEating plants
Secondary consumerEating primary consumers
Tertiary consumerEating secondary consumers
HerbivoreEating plants
CarnivoreEating other animals
DecomposerFeeding on dead and decaying organisms, and on the undigested parts of plant and animal matter in faeces