Boxi Learn › Science › Stage 2 · Models and Patterns
Who eats whom, and where the energy goes
SCI-3 Energy changes form but is never made or lostSCI-4 Living things survive by their structure
What many people think
Predators are at the top because they are strongest.
The idea
Each step up a food chain passes on only about a tenth of the energy; the rest is used for living and lost as heat.
Explain it
A field has thousands of grasshoppers but only a few hawks. Explain why to a friend without using the words ‘strong’ or ‘weak’.
Try at home
Count out 100 grains of rice for the grass. Pass a tenth to a ‘grasshopper’ cup, then a tenth of that to a ‘frog’ cup. What is left for a snake? Then look in a park or garden: who eats whom?