Final answer:
On average, only 10 percent of energy is transferred from one trophic level to the next in a food chain, while the remaining 90 percent is used or lost as heat and waste due to metabolic processes.
Step-by-step explanation:
The average amount of energy passed through each trophic level of a food chain is about 10 percent. As energy moves from one trophic level to the next, 90 percent is typically used for metabolism, growth, and repair, or is lost as heat and waste.
This significant loss of energy from one trophic level to the next is a consequence of the second law of thermodynamics, where energy conversions are accompanied by an increase in entropy (disorder), resulting in energy loss as heat.
The studies conducted by Howard T. Odum in the Silver Springs ecosystem demonstrated this concept, showing a progressive decrease in energy available at each successive trophic level, with primary producers generating 20,819 kcal/m²/yr, primary consumers 3368 kcal/m²/yr, secondary consumers 383 kcal/m²/yr, and tertiary consumers a mere 21 kcal/m²/yr.