Question

In the following food chain, 20000J of energy was available to the plants. How much energy would be available to man in this chain?
Plants ->Sheep->Man​

Answer 1

200j according to 10percent law

Answer 2

The correct answer should be - 200 J of energy.

Going by the hierarchy of the Trophic levels, the plants are primary producers, the herbivores are the primary consumers, and the carnivores are the secondary consumers.

So, according to the 10% law, at every trophic level, the energy is lost in the food due to biological processes like digestion, or energy lost during transfer or during the breakdown of respiration and other functions. Only 10% of the energy is stored in the flesh or in the body parts.

Therefore according to the 10% rule, if the plants have 20000 J of energy, then when it comes down to next trophic level of the herbivores, the energy level will come down to 2000 J. When it comes down to the next trophic level of the carnivores that includes Man, the energy available will be only 200 J.