Food chains

Reading the arrows

A food chain always starts with a producer — a green plant, because only plants make their own food. Then come the consumers. The arrow means is eaten by, so it points in the direction the energy travels, from the food to the eater.

Predator and prey

The animal that hunts is the predator; the one hunted is the prey. An animal can be both: a frog is prey to a snake but a predator of flies.

When one link changes

Remove a link and the whole chain feels it. Fewer grasshoppers means less food for birds, and it also means the grass grows thicker.