How is a food chain poisoned

Food chain

An example of a food chain: eagles eat snakes. The snake has eaten a mouse. The mouse has eaten an insect. The insect has eaten a leaf.

Most living things eat other living things and are eaten themselves. This is called a food chain. For example, there are small crabs that eat algae. Fish eat the crabs, herons eat the fish and wolves eat the herons. They all hang one behind the other, like pearls on a chain. That is why one speaks of the food chain.

The food chain is a term from biology. That is the science of life. All living things need energy and building blocks in order to live. Plants get this energy from sunlight. They get the building blocks for growth from the roots through the roots.

Animals can't do that. They therefore get their energy from other living beings that they eat and digest. These can be plants or other animals. So the food chain means: energy and building blocks go from one species to another.

This chain doesn't go on forever. Sometimes one species is at the end of the food chain. For example, humans eat all kinds of animals and plants. But there is no animal that eats people. In addition, people can now defend themselves against attacks by animals with weapons.

What happens at the end of the food chain?

The fact that humans are at the end of the food chain also brings them problems: A plant can absorb a poison, for example a heavy metal such as mercury. A small fish eats the plant. A big fish eats the little fish. The heavy metal always goes with it. In the end, humans catch large fish and then eat any heavy metals that have accumulated in the fish. So he can poison himself over time.

Basically, the food chain has no end, because people die too. After their death they are often buried in the ground. There they are eaten by small animals like worms. So food chains actually tend to form circles.

Why is the idea of ​​the chain not entirely appropriate?

Many plants or animals not only eat a different species. Some are even called omnivores: They eat different animals, but also plants. The rats are an example. Conversely, grass, for example, is not only eaten by one species of animal. So one would at least have to speak of several chains.

So sometimes you think of all the animals and plants that live in a particular forest, or in the sea, or all over the world. This is also called an ecosystem. One then usually speaks of a food web. The plants and animals are nodes of the web. They are connected to one another by eating-and-being-eaten.

Another picture is the food pyramid: humans, it is said, are at the top of a food pyramid. At the bottom there are a lot of plants and small animals, in the middle there are some larger animals. A pyramid is wide at the bottom and narrow at the top. So there are a lot of living things further down. The more you get up, the less it gets.

There is also an article on “Food Chain” for beginners on and other search results from Blinde Kuh and Ask Finn.

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