Pyramid of energy give the best picture of overall nature of the ecosystem. It is a picture of the rate of passage of food mass through the food chain. It is always upright because energy flow in ecosystem is unidirectional and there is always a gradual decrease in the energy content at successive trophic levels from the producers to various consumers. Pyramid of biomass is inverted in pond ecosystem, as the producers are small organisms, their biomass is least which, gradually increase towards the apex. Pyramid of number is inverted in parasitic food chain. This is due to the fact that a single plant may support the growth of many herbivores and each herbivore in turn may provide nutrition to several parasites which support many hyper-parasites.