Question

Which one of the following animals may occupy more than one trophic level in the same ecosystem at the same time?
A. Sparrow
B. Lion
C. Goat
D. Frog

Answer 1

Hint: Food chain is the linear flow of energy from one trophic level to another through food. The flow of food is very essential as the organisms gain energy mainly through the food that is passed on at different trophic levels in an ecosystem.

Complete answer:
To answer this question, we need to understand the different trophic levels in the food chain. As mentioned above, the food chain is a linear flow of energy in the form of food through different trophic levels. Food chain is mainly of two types which is the grazing food chain and the detritus food chain. The difference between the two is that the grazing food chain starts with green plants and in the detritus food chain it starts with dead and decaying matter. The energy in the grazing food chain comes from the sun and in the detritus food chain the energy is derived from the detritus.
With that introduction let us see the different trophic levels in the grazing food chain. The first level is the producer. Producer is the autotrophic plants that produce their own food.
The organism which feeds on the plant parts (seeds, fruits, leaves etc.) are the primary consumers. It can be different organisms such as worms, insects, birds, herbivorous mammals etc.
The organisms that feed on these primary consumers are called the secondary consumers and the examples for them are insectivorous birds, small carnivores.
The organisms that feed on the secondary consumers are called tertiary consumers and the organisms that feed on the tertiary consumers are called the quaternary consumers. They are generally the larger carnivores.
Here, as we can see, birds like sparrow can feed on both plant parts and also on insects. When they feed on plant parts, they are the primary consumer and when they feed on insects, worms etc., they are the secondary consumers.

Hence, the right answer is A – Sparrow.

Note: Food web is an important ecological aspect. Food web is the complex and natural interconnections of different food chains in an ecosystem. Food chain depicts the flow of energy through different food chains. It gives an overall picture of the ecosystem.