Ecosystem Game

Ecosystem Game is a free food chain game you play in your browser, with no download or sign-up. Build food chains and food webs from eight habitats, keep a little meadow in balance in a predator and prey simulation, and then test what you learned in a quick quiz. It works on a computer, tablet or phone.

How to play

Food chains and food webs

• Food chains (levels 1 to 12): drag each living thing into a box, producer first, or tap a card and then tap a box. Arrows show energy flowing from the food to the eater. From level 7, some chains add a decomposer box for fungi, earthworms, termites or bacteria.
• Food webs (levels 13 to 18): draw arrows yourself. Drag from a food to the animal that eats it, or tap the food and then the eater. Draw the same arrow again to remove it.
• Check: wrong boxes or arrows turn red and you get a hint. Solve a level on the first check for 3 stars, on the second for 2, and after that for 1.

The levels visit a meadow, a pond, the ocean, a forest, the savanna, the Arctic, a desert and a rainforest. Every pairing is a real one: phytoplankton, zooplankton, Arctic cod, ringed seal and polar bear in the Arctic, or kelp, sea urchin, sea otter and orca in a kelp forest.

Balance the meadow

The second part is a small ecosystem simulation with grass, rabbits, foxes, and fungi and worms, plus a soil nutrient meter. Use the buttons to add grass, rabbits, foxes or decomposers, or to move some foxes or rabbits away, then press Play. A graph tracks every population day by day.

Each of the six scenarios has a goal: build a meadow from bare soil, rescue rabbits from too many foxes, stop a rabbit boom from eating all the grass, fix tired soil, recover from a drought, and keep everything alive for 120 days. If a species dies out, the scenario ends with a reason so you can try a new plan. Meeting the goal within the par number of actions earns 3 stars. The same plan always gives the same result.

Quiz

Two rounds of 10 questions: one on ecosystem words like producer, consumer, decomposer, habitat and food web, and one on energy and roles. Score 10 for 3 stars, 8 or more for 2 and 5 or more for 1.

Tips

• Start with the producer. Every food chain begins with something that makes its own food from sunlight by photosynthesis: grass, a tree, algae, kelp or phytoplankton.
• Read arrows as “is eaten by”. An arrow from grass to rabbit means the rabbit eats the grass, so energy flows from the food to the eater.
• Find the decomposer by what it eats. Decomposers do not hunt. They break down dead plants and animals and return nutrients to the soil.
• In the balance sim, small changes go a long way. Too many foxes crash the rabbits, and then the foxes starve. With no foxes, rabbits multiply until the grass runs out. Change one thing at a time and watch the graph.
• Don’t forget the soil. Without fungi and worms, dead matter piles up and soil nutrients fall, so the grass slowly grows less.

FAQ

What is a food chain?

A food chain shows who eats whom, step by step, starting with a producer. For example, grass is eaten by a rabbit, and the rabbit is eaten by a fox. The arrows point from the food to the eater because they show the direction energy flows.

What is the difference between a food chain and a food web?

A food chain is one path. A food web links many food chains together,. In the meadow web, mice are eaten by both foxes and owls.

Why are there fewer predators than plants?

Only about 10% of the energy at one level of a food chain passes on to the next. The rest is used for living or lost as heat, so each level supports fewer living things.

Is the balance simulation realistic?

It is a simple model, not a forecast. It follows the same basic rules as real predator and prey studies: prey grow when food is plentiful, predators grow when prey is plentiful, and too many of either leads to a crash.

Is Ecosystem Game free, and does it save my progress?

Yes. It is completely free, and your stars are saved in your browser on this device.

Like science games? Try the Science Game lab, or set up a freshwater tank and learn the nitrogen cycle in the Aquarium Game.