Question

Why are there fewer organisms in higher trophic levels?

A) Higher trophic levels have less access to sunlight.
B) Organisms at higher trophic levels have longer lifespans.
C) Energy is lost as heat at each trophic level.
D) Higher trophic levels have more efficient predators.

Answer 1

There are fewer organisms at higher trophic levels because energy is lost as heat at each level, with only about 10% passing on to the next level.

Step-by-step explanation:

There are fewer organisms at higher trophic levels primarily because energy is lost as heat at each trophic level. Only about 10 percent of the energy at one trophic level is passed on to the next higher trophic level, while the remaining 90 percent is used up for metabolism, growth, repair, or lost to the environment as heat or incompletely digested food. This significant loss of energy at each trophic level limits the number of organisms that can be supported at higher levels, resulting in fewer organisms and less biomass at these higher trophic levels.

The correct answer to the given multiple-choice question would be C) Energy is lost as heat at each trophic level. This limitation is also why there are rarely more than four trophic levels in an ecosystem because there is inadequate energy to support viable populations at additional higher levels.