What percentage of energy from a lower trophic level is typically transferred to the next higher trophic level in an ecosystem?

• A. About 90%
• B. About 10%
• C. About 1%
• D. About 50%

Answer: (B)

Verified step by step guidance

1. Understand the concept of energy transfer in ecosystems: Energy flows through trophic levels in a food chain, starting from producers (plants) to primary consumers (herbivores), secondary consumers (carnivores), and so on. Only a fraction of energy is transferred from one level to the next.
2. Learn about the 10% rule: In general, only about 10% of the energy at one trophic level is transferred to the next higher trophic level. The remaining energy is lost as heat, used for metabolic processes, or left in unconsumed biomass.
3. Analyze the options provided: The question asks for the percentage of energy transferred to the next trophic level. Compare the given options (90%, 10%, 1%, 50%) with the 10% rule.
4. Eliminate incorrect answers: 90% and 50% are too high, as most energy is lost between trophic levels. 1% is too low, as the typical transfer is closer to 10%. This leaves 10% as the correct answer.
5. Conclude with the ecological significance: The 10% rule highlights the inefficiency of energy transfer in ecosystems, which limits the number of trophic levels and impacts population sizes at higher levels.