Food Chains

A food chain shows who eats what in nature, and how energy is passed along from one living thing to the next. Almost every food chain on Earth begins with the same source: the Sun. Plants capture sunlight and use it to make their own food, and that captured energy then flows up the chain each time something is eaten.

We give the members of a food chain special names based on their job. Plants are producers, because they produce (make) their own food using sunlight. Animals are consumers, because they cannot make food and must consume (eat) other living things. The first animal in a chain that eats plants is the primary consumer, and the animal that eats that one is the secondary consumer.

Animals at the top of a food chain, like foxes, eagles, and lions, are called predators because they hunt other animals. The animals they hunt are called prey. Many animals are both predator and prey at the same time: a frog is a predator when it catches a fly, but prey when a heron swoops down to eat the frog.

In real nature, animals rarely eat just one thing. A fox eats rabbits, mice, birds, and even berries. When lots of food chains link together, they form a food web — a tangled map of who eats whom. If one animal disappears from a web, every creature connected to it is affected, which shows how delicately balanced nature really is.

There is one more vital group: the decomposers. When a plant or animal dies, tiny living things like worms, fungi, and bacteria break the dead body down. This releases the goodness locked inside back into the soil, so producers can use it to grow. Without decomposers, dead plants and animals would pile up and the nutrients would never be recycled.