Every time energy is transferred from one organism to another, there is a loss of energy. This loss of energy can be shown in an energy pyramid.
Each step of the food chain in the energy pyramid is called a trophic level. Plants or other photosynthetic organisms (autotrophs) are found on the first trophic level, at the bottom of the pyramid.
Heterotrophs are found in all levels of an energy pyramid other than the first level.
As energy is transferred along a food chain, energy is lost as heat.
Only about 10% of energy of one step in a food chain is stored in the next step in the food chain.