PRODUCERS AND CONSUMERS
FOOD PYRAMIDS
On the right is a food pyramid.
It shows how consumers can get larger in size, but smaller in number, as you go along the food chain.
When a moth caterpillar eats a leaf it uses up some of the energy from the leaf for itself.
So there is less to pass on to a robin. That means the robin needs to eat several moth caterpillars to get enough energy. So there are fewer robins than caterpillars.
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