How do food webs differ from simple food chains?

Food webs are more complex and interconnected than simple food chains, showing multiple feeding relationships.

A food chain is a linear sequence that shows how energy and nutrients are transferred from one organism to another within an ecosystem. It starts with a producer (usually a green plant) that gets its energy from the sun. This is then eaten by a primary consumer (an herbivore), which is then eaten by a secondary consumer (a carnivore), and so on. Each step in this process is known as a trophic level. However, this is a simplified model and doesn't fully represent the complexity of nature.

On the other hand, a food web is a more accurate representation of the feeding relationships within an ecosystem. It consists of multiple food chains that are interconnected. This means that one organism can be part of several food chains. For example, a rabbit might eat grass, but it could also be eaten by a fox or a hawk. This shows that the rabbit is part of multiple food chains, which are all part of the same food web.

Food webs also show the concept of omnivores, organisms that eat both plants and animals, which is not typically represented in a simple food chain. Moreover, food webs illustrate the idea of a 'circular' flow of energy and nutrients, rather than a linear one. This is because when an organism dies, its body is broken down by decomposers (like bacteria and fungi), returning the nutrients back to the soil where they can be used by plants, starting the cycle again.

In summary, while food chains provide a simple way to visualise the basic principle of energy transfer in ecosystems, food webs offer a more comprehensive and realistic view of the complex interrelationships between different organisms and their environment.