The food chain is the food relationship between producers, consumers and decomposers. In simple words, a food chain reflects who eats whom.
A living being feeds on what precedes it in the food chain, such as plants, and in turn, is eaten by the next, which can be another animal or a human.
The food chain begins with the producers. We can start it with photosynthetic plants that can create matter to feed themselves from inert materials.
Through the process of photosynthesis, these plants transform water and mineral salts into food to feed themselves.
They are also called autotrophic beings because they do not need another living being to feed. In this link in the chain we only find plants.
In the next link in the chain we find the primary consumers or phytophagous. These are herbivorous living things that feed on producers, in this case plants. They use plants as their main sustenance since they are unable to produce food by themselves.
These primary consumers are in turn consumed by secondary consumers or carnivores. Carnivorous animals feed on herbivorous animals which in turn feed on plants.
We can also make a distinction between tertiary consumers if we are in an ecosystem where they feed on secondary consumers due to a situation of superiority.
As matter is neither destroyed nor created, at the moment in which secondary consumers die, we need another organism that is in charge of turning them into food for another individual in the chain.
This is where bacteria and fungi, or decomposing organisms, enter. These are responsible for breaking down the remains of the members of the food chain to turn them into essential elements for plants.
There are examples of food chains where up to seven levels of participants can be trained. In a food chain, all the members are essential to maintain the balance of the ecosystem.
The disappearance of one of the links can endanger the entire ecosystem in which the food chain is located.
To represent the relationships in a food chain we can use food webs. It indicates the relationships of the members of the ecosystem based on the main
Featured examples of food chains
-The plant phytoplankton found at the bottom of the oceans feed krill, a small crustacean. Small ocean fish feed on krill while in turn being preyed upon by larger fish such as barracuda or whales. When older fish die, they are converted into inorganic matter through decomposers, which serves as food for phytoplankton in the ocean.
-Plants that have fleshy leaves are parasitized by insects such as caterpillars. These become butterflies, which feed small birds while they are preyed upon by larger animals such as wildcats or eagles, which in turn will be decomposed by bacteria once they have died.
-Flying insects, such as the lobster, feed on plant leaves. Toads eat insects and are in turn eaten by rodents. These small rodents are in turn eaten by snakes and other reptiles, which will become food for bacteria and fungi.
-Marine zooplankton and krill crustaceans are the main food of the whales. They capture their food by the ton, and are eaten by man. Much of the organic matter of the whales returns to the seas and oceans as waste, which becomes the main food of zooplankton.
-The bark of trees serves as the main sustenance for many parasitic fungi that inhabit them. These insects are eaten by small rodents that in turn are preyed upon by birds of prey such as the owl.
-Dung beetles are one of the largest groups of decomposers of the feces of higher animals. Beetles are the food of lizards, which in turn are eaten by quadruped mammals such as coyotes.
-Once the body of an animal is dead, it serves as an incubator for many insects, among these we find the larvae of the fly. Once they start to fly, they become the victim of other insects such as spiders. The spiders in turn serve as food for small birds, which are in turn eaten by larger carnivorous birds.
-The bees feed on the nectar of the flowers, and become the food of small birds. Birds lay eggs that serve as sustenance for many rodents such as the opossum, which serves as sustenance for snakes and birds of prey
-Herbivorous animals like the zebra, feed on plants and small shrubs. Zebras serve as food for large predators such as crocodiles. However, these are not hunted by any other animal or by man, in most cases. They return to the food chain once they die and bacteria break them down into organic matter that nourishes the plants on the banks of the rivers that in turn serve as food for the zebras.
-The worms that eat the wood of the trees, serve as the main sustenance of birds. These birds lay eggs that are eaten by rodents, or at the same time, the birds can become food for other larger birds. These large birds, once dead, will serve as food for bacteria, which will nourish the trees and their bark for worms.
References
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