If you're like most kids, you probably hunt for most of your food in the aisles of your local grocery store. If you're hungry for some crunchy green vegetables, you can head over to the produce aisle and stalk some wild celery. Or if pizza sounds good, you can hide out in the frozen food aisle until just the right moment to snatch that frozen pizza from the freezer!
In many places around the world — and for wild animals — finding food to sustain life is not nearly as easy as a trip to the supermarket. In the wild, it often comes down to a simple question: are you predator or prey? And the answer is sometimes both!
All living things need energy. Energy comes from the foods we eat. A food chain is a simple way of explaining how each living thing gets its food. For example, a simple African food chain might consist of three parts: (1) trees and bushes; (2) giraffes; and (3) lions. Giraffes eat trees and bushes for food, and lions eat giraffes.
Each link in a food chain is food for the next link. Food chains always start with plants and end with animals.
Plants are at the bottom of the food chain. Scientists call them producers, because they use light energy from the sun to produce food from carbon dioxide and water through photosynthesis.
Animals, unlike plants, can't produce their own food. Instead, they must eat plants or other animals. This is why scientists call them consumers.
In addition to producers and consumers, there are also decomposers. These organisms, such as bacteria and fungi, feed on matter. They help the food chain by speeding up the process that releases minerals back into the soil to be absorbed by plants as nutrients.
Most food chains have only four or five links in them. As you go up a food chain, the amount of energy at each level decreases, because some of the energy is lost in the form of waste or is used up by the organism at that level. That is why it takes many plants, for example, to feed a few giraffes who in turn feed one lion.
Most animals are part of many different food chains, because they must eat more than one type of food to satisfy their energy needs. All of these interconnected food chains form a more complex structure called a food web.
Humans, for example, are at the center of a very complex food web, because we tend to eat many different types of plants and animals. And unlike what you may have read in fairy tales, there aren't many animals that look at humans as food.
The only creatures who might snack on a human are large predators, such as sharks. However, it's very rare for humans to be eaten by predators. Most predators have more to fear from humans than we have to fear from them!