This, too, diminishes with the distance along the food chain from the autotrophs which make the organic molecules in the first place. The graphic shows the pyramid of biomass for Silver Springs. The Pyramid of Numbers Small animals are more numerous than larger ones. This graph shows the pyramid of numbers resulting when a census of the populations of autotrophs, herbivores, and two levels of carnivores was taken on an acre of grassland. So, if the size of the individuals at a given trophic level is small, their numbers can be large and vice versa.
Predators are usually larger than their prey.
Occupying a higher trophic level, their biomass must be smaller. Hence, the number of individuals in the predator population is much smaller than that in the prey population. The graphic represents a pyramid of numbers in an acre of bluegrass. The figures represent number of individuals counted at each trophic level. The pyramid is based on data acquired by Evans, Cain, and Walcott, and has been redrawn by permission from E. P. Odum, Fundamentals of Ecology , 2nd.