They would use it to show the flow of energy through an ecosystem.
Explanation:
A food web is the network of interconnected food chains. It represents the branched food chains wherein one plant species serve as food for many different primary consumers and one specific primary consumer feeds on various plant species. Food webs represent the flow of energy from one tropic level to next through ecosystem.
Food webs show the flow of energy (stored as organic molecules) through ecosystems. Thus, a scientist would use a food web to show the flow of energy through an ecosystem.
