Living organisms get energy from food which gives them the energy to grow and move.
A food chain shows the links between different organisms based on the food they eat. A plant is referred to as a producer because it can make its own food. The first animal to eat the producer is the primary consumer, followed by a third consumer, fourth consumer until the energy from the food chain ends with decomposers.
The grass (primary producer) is eaten by the Grasshopper (consumer) who is eaten by the Toad (consumer) who is eaten by the Snake (consumer) who is eaten by the Hawk (consumer).
Living organisms have to have some type of energy to be able to live and survive.
The sun gives energy to all living things because the energy from the sun goes into the plants and the plants at the base of the food chain get this energy because of photosynthesis.
Photosynthesis is how plants make energy. They must have sunlight, water, carbon dioxide, and minerals in order for the process of photosynthesis to work.
The sun shines on the plant and the carbon dioxide is absorbed by the plant.
The plant uses carbon dioxide to make sugar which is called glucose. This glucose gives energy to the plant.
Herbivores are animals that eat plants in an ecosystem.
When an animal eats plants, they get energy.
Carnivores are animals that eat other animals.
When a carnivore eats a herbivore, the energy that the herbivore got from the plant transfers to the carnivore.
When one animal eats something, the energy that they got transfers to the next thing that eats them. This is all part of the natural food chain.
Here is a great example:
Herbivore eats a plant – The energy from the plant goes to the herbivore.
Carnivore eats an herbivore – The energy that the herbivore got from the plant goes to the carnivore.
When all of this happens, it is called the food chain. Energy must transfer from one organism to the next in order for it to be the food chain.
Everything that is alive must have a source of energy in order to grow and this energy has to come from somewhere.
The food chain starts with two types of organisms:
Producers-organisms that make their own food such as plants.
Consumers-animals that consume or eat other organisms.
grass —> zebra —> lion
Grass = Primary Producer
Zebra = Primary Consumer
Lion = Secondary Consumer
When an animal eats an animal or an organism, they get energy from what they eat.
As the food chain increases, less energy is available.
Animals such as zebras and lions use a lot of the energy, they get to live with activities such as:
Examples of Food Chains
Flowers – butterflies – small birds – foxes.
Dandelions – snail – frog – bird – fox.
Dead plants – centipede – robin – raccoon.
Decayed plants – worms – birds – eagles.
Fruits – tapir – jaguar.
Fruits – monkeys – monkey-eating eagle.
Grass – antelope – tiger – vulture.
Grass – cow – man – maggot.
Each link in the food chain is important.
All animals rely on other parts of the chain in order to live.
If there was no grass, the tigers would eventually die, even though tigers do not eat grass.
Since tigers eat other animals such as deer, if the deer had no grass to eat, the deer would die, and then there would be nothing for the tiger to eat.
All levels of the food chain are important
Most organisms or animals eat or get eaten by different animals.
The food chain is not able to really show this and that is why there is something called the food web.
Food webs show all the different connections between animals and organisms, but it can be very complicated since there are so many different creatures.
One example is the African savannah food web.
This food web shows this:
Apex Predator is a very important part of the food cycle.
The Apex Predator is top of the ecological pyramid and helps to balance the ecosystem by helping to keep the population of animals below them in check so that they do not overpopulate.
The Apex Predator eats on all animals under it in the food web, but it has nothing that eats it, or it has no predators.
Decomposers are part of the consumer group.
Decomposers are different types of organisms that break down things that die such as animals or plants.
The decomposers will turn the dead animal or plant into different nutrients and the nutrients will go into the soil.
Some types of decomposers include:
When the nutrients go into the earth, it helps the food cycle because bugs or insects in the soil will help to break down things that die.
Some insect decomposers include:
If there were no decomposers, then there would not be nutrients that would get back to the soil.
Things that would die would just continuously pile up and it would cause animals and people to get sick from bacteria.
Another type of consumer is an omnivore.
An omnivore eats animals and plants.
Some examples of omnivores include:
Some scientists describe the food web in five different trophic levels. These include:
People can cause the population of animals to overpopulate because of overhunting.
For example: if people hunt too many coyotes, there can be too many deer that live because the coyotes are dead and do not hunt the deer.
When there are too many deer left, the deer can eat too much grass, or they can overpopulate and become ill and die.
People also affect the food chain when they cut down too many forests. When this happens, it causes soil to erode and it can kill fish that are in the rivers and the streams.