Why is a pyramid of biomass more useful for showing what's happening in a foodchain than a pyramid of numbers?

Question

For my biology homework - I'm a bit confused.

Answer 1

Not all organisms have the same mass.  Consider 1 whale versus 5,000 plankton - the whale has much greater mass, but only 0.1% of the total number of organisms.  When you compare mass, you get a better idea of how much energy is actually available at that trophic level.