Question

What is the reason that a food chain consists of only 3-5 steps?

Answer 1

The transfer of food and energy from one organism to the other and to different trophic levels occurs by food chain. Many food chains intertwine making food webs as several organisms consume more than one type of plant or animal like the omnivores.

Complete answer:
Plants make their own food by converting the light energy from the sun into chemical energy by the process of photosynthesis. They are known as autotrophs or producers which are eaten by consumers and the consumers are divided into primary, secondary, tertiary and so on. Food chains consist of different trophic levels among which the food and energy is transferred. At each trophic level a lot of energy is lost in the form of heat or is used for the maintenance because of which only 10% energy is transferred to the next trophic level. As such little amount of energy is transferred the trophic levels/ steps are limited to 3-5 only.

Additional information:
-The 10 % rule of energy efficiency was given by Raymound Lindeman.
-10 % energy that is transferred from one trophic level to the other higher trophic level is fixed in the flesh of an organism which is transferred to the organism which eats it.

Note: This 10% energy transfer can be increased if we start eating plant based food more as compared to animal based food. Instead of eating animals that eat grains (like chicken) , eating grains directly will increase the energy transfer as the energy from the producer will be directly transferred to the consumer.