Ecological Pyramids Ecological Pyramids Ecological pyramids are graphical representations of the number of individuals in different nutritional levels. Plants absorb energy from the sun, the insects eat the plants, the birds eat the insects, and the hawks eat the birds. Hence, the energy of the sun has been transferred from the sun to the tissues of the hawk. Since the number of individuals in each level usually decreases, the resulting diagram looks like a pyramid. The number of individuals does not always decrease.
Ecological pyramids represent the basic laws of energy.
The first law of thermodynamics states that the amount of energy remains constant. Therefore, ecological pyramids represent the transfer of energy from one level to another. The laws of thermodynamics ensure the pyramid of energy to be a true pyramid.