Notes
DISCOVERY FILE: Food Chains and Food Webs
All animals need energy to run, breathe, and hunt, and they get this energy by consuming food. Think about what you ate today: that is helping you walk, think, and read! Food chains and food webs are similar to each other, but they are not the same. We will explore the differences here.
A food chain shows a single, connected path of energy flow through an ecosystem. Some animals only eat plants while some animals eat other animals. A food chain shows the different levels of eating within an ecosystem. The arrows show the flow of energy from one organism to the next. Most food chains begin with the sun at the bottom. Let’s examine the example on the right.
There are three types of organisms in a food chain: producers, consumers and decomposers.
1. Producers. These organisms absorb the sun’s energy and convert the energy into food for themselves, allowing them to grow larger, make flowers and fruit, etc. An example of a producer is a plant, such as the flower in the picture.
2. Consumers. These organisms, mostly animals, can be split into a few categories:
Primary consumers only eat plants, so they are called herbivores. The primary consumers in the picture are the bee and grasshopper.
Secondary consumers eat primary consumers. Many secondary consumers also eat plants, which makes them omnivores (meat and plant eaters). The secondary consumers in the picture are the wasp and beetle.
Tertiary consumers eat the secondary consumers and are usually carnivores (meat eaters). The tertiary consumers in the picture are the frog and snake.
Quaternary consumers eat the tertiary consumers and are carnivores. The quaternary consumer in the picture is the hawk. In this picture, the food chain ends with the hawk, which claims the title as the top carnivore.
3. Decomposers. These organisms turn dead material (such as a fallen tree, or a dead hawk) into soil and recycle nutrients so they can be re-used by producers to
All animals need energy to run, breathe, and hunt, and they get this energy by consuming food. Think about what you ate today: that is helping you walk, think, and read! Food chains and food webs are similar to each other, but they are not the same. We will explore the differences here.
A food chain shows a single, connected path of energy flow through an ecosystem. Some animals only eat plants while some animals eat other animals. A food chain shows the different levels of eating within an ecosystem. The arrows show the flow of energy from one organism to the next. Most food chains begin with the sun at the bottom. Let’s examine the example on the right.
There are three types of organisms in a food chain: producers, consumers and decomposers.
1. Producers. These organisms absorb the sun’s energy and convert the energy into food for themselves, allowing them to grow larger, make flowers and fruit, etc. An example of a producer is a plant, such as the flower in the picture.
2. Consumers. These organisms, mostly animals, can be split into a few categories:
Primary consumers only eat plants, so they are called herbivores. The primary consumers in the picture are the bee and grasshopper.
Secondary consumers eat primary consumers. Many secondary consumers also eat plants, which makes them omnivores (meat and plant eaters). The secondary consumers in the picture are the wasp and beetle.
Tertiary consumers eat the secondary consumers and are usually carnivores (meat eaters). The tertiary consumers in the picture are the frog and snake.
Quaternary consumers eat the tertiary consumers and are carnivores. The quaternary consumer in the picture is the hawk. In this picture, the food chain ends with the hawk, which claims the title as the top carnivore.
3. Decomposers. These organisms turn dead material (such as a fallen tree, or a dead hawk) into soil and recycle nutrients so they can be re-used by producers to