Which trophic level is supported by the least amount of energy in an ecosystem?

Trophic levels represent the different stages in a food chain, each corresponding to a certain position in the ecosystem's energy flow. At the base of this hierarchy are producers, which harness energy from the sun through photosynthesis, converting solar energy into organic material. As energy flows through different levels from producers to various types of consumers, a significant amount of energy is lost at each stage, primarily through metabolic processes and heat.

Tertiary consumers, being at the top of the food chain, receive the least amount of energy. This is due to the energetic inefficiency of transferring energy from one trophic level to the next. Generally, only about 10% of the energy from one level is passed on to the next, known as the 10% rule. Consequently, the higher the trophic level, such as that of tertiary consumers, the less available energy there is to support those organisms. This results in a lower biomass and population size at this level compared to producers and lower consumer levels.

In summary, since tertiary consumers occupy the highest trophic level and thus receive the least energy transferred from producers and other consumers, they are supported by the least amount of energy in an ecosystem.