What are primary consumers

Question

Explain what do you mean by the primary consumers? Whether food chain has the quaternary consumers without having the secondary or the tertiary consumers? Specify whether a tertiary consumer of one chain can be a primary or secondary consumer of other chain?

Answer 1

Primary consumers are the living beings which generally eat the autotrophic beings, i.e., they may eat the producers. Primary consumers always belong to the second tropic level of the chain.

A food chain may not have the consumers of superior orders without having consumer of inferior orders. A consumer though may take part within the many different chains not always belonging to same consumer order within each of them.