Think about how the amount of energy changes as you move stepwise from producers to primary consumers to tertiary consumers in a food chain. Which shape could you use to model the quantities of energy at all of these types?
Circle
Square
Triangle
Line
Yah its a triangle
I think it is Circle. Am I right?
Nope.
Energy is maximum at the level of producers, and then decreases upwards; only 10% of energy is carried on to the next trophic level.
Hence, an energy pyramid diagram for ecosystem studies shows a triangular shape.