<P> The bottom of the pyramid represents the primary producers (autotrophs). The primary producers take energy from the environment in the form of sunlight or inorganic chemicals and use it to create energy - rich molecules such as carbohydrates . This mechanism is called primary production . The pyramid then proceeds through the various trophic levels to the apex predators at the top . </P> <P> When energy is transferred from one trophic level to the next, typically only ten percent is used to build new biomass . The remaining ninety percent goes to metabolic processes or is dissipated as heat . This energy loss means that productivity pyramids are never inverted, and generally limits food chains to about six levels . However, in oceans, biomass pyramids can be wholly or partially inverted, with more biomass at higher levels . </P> <P> Terrestrial biomass generally decreases markedly at each higher trophic level (plants, herbivores, carnivores). Examples of terrestrial producers are grasses, trees and shrubs . These have a much higher biomass than the animals that consume them, such as deer, zebras and insects . The level with the least biomass are the highest predators in the food chain, such as foxes and eagles . </P> <P> In a temperate grassland, grasses and other plants are the primary producers at the bottom of the pyramid . Then come the primary consumers, such as grasshoppers, voles and bison, followed by the secondary consumers, shrews, hawks and small cats . Finally the tertiary consumers, large cats and wolves . The biomass pyramid decreases markedly at each higher level . </P>

Who has the greatest biomass in a food chain