Food Chain Builder

The big ideas

What the levels teach, in grown-up words.

• Every food chain starts with the sun. Plants capture sunlight and make their own food. Everything else eats plants, or eats something that ate plants. Scientists call plants producers and animals consumers.
• The arrows show where energy goes. An arrow points from the food to the eater: grass to rabbit, rabbit to fox. Reading the arrows tells you who depends on whom.
• Break a link and the whole chain feels it. Without foxes, rabbits boom, strip the grass, then starve. Without grass, rabbits dwindle and the foxes that never touched a blade of grass go hungry too.
• Real life is a web, not a chain. Most animals eat several things and are eaten by several others, which is what makes ecosystems tough but not unbreakable.
• Decomposers close the loop. Worms, fungi and beetles break dead plants and animals down into soil, and plants grow from that soil. Energy flows one way, but the materials go round.
• Energy is lost at every step. Only about a tenth of the energy in grass ends up in the grasshopper that eats it, which is why a meadow needs a thousand plants to support a single hawk.

Try it at home

Quick experiments that match the game.

1. Dinner chain. At a meal, trace each food back to the sun: bread came from wheat that grew in sunlight; cheese came from a cow that ate grass.
2. Garden detectives. Look under a log or a stone and find the clean-up crew: worms, woodlice, beetles. Put the log back gently.
3. Who eats what? Pick a local animal and find out what it eats and what eats it. Draw the chain with arrows pointing toward the eater.
4. Pyramid of snacks. Use 10 raisins, 3 crackers and 1 cookie to build an energy pyramid, and talk about why there is only one cookie.