Question

Why are there rarely more than five links (or five organisms) in a food chain?

Answer 1

There are rarely more than five links (or five organisms) in a food chain because, according to the 10 per cent law, only 10 per cent of the available energy is transferred to the next trophic level. So, at the higher trophic levels, the amount of energy is reduced to such an extent that it becomes insufficient for an organism to sustain itself.