Food chains & Webs

All life on earth ultimately derives its energy from the sun. Green plants fix this energy in a process called photosynthesis; taking Carbon dioxide gas, water and sunlight energy to make simple sugars and from them all of their complex materials. Animals either eat green plants directly or they eat other animals that have eaten green plants.

Green plants = PRODUCERS
Herbivorous (plant eating) animals = PRIMARY CONSUMERS
Carnivorous (meat eating) animals = SECONDARY CONSUMERS
Animals and Fungi that eat dead material (plant and animal) = DECOMPOSERS

In this way energy flows through an eco system, from plants to primary, then secondary consumers and eventually to decomposers. This energy flow can be represented as a food chain. Two examples from Lebanon are shown below:

A Food Chain of the Rocky Slopes

A Food Chain of a Freshwater Wetland

Food Web of a Lebanese Freshwater Wetland

Food chains are of course an oversimplification as animals eat and are eaten by many different species. The reality is more closely represented by food webs. The food chain above is shown as part of the food web of a Lebanese freshwater wetland below: