Introduction: Energy travels through ecosystems by getting passed from one organism to the next. The Sun is the ultimate source of energy that can be passed on, however a lot of the Sun's energy is lost to the organism's own metabolism. Much of the study of ecosystems investigates which organisms are eating each other and how they are able to pass the energy along.
The transfer of energy from one organism to another can be illustrated in a food chain. At the bottom of the chain are those organisms that make their own energy. These are called producers. Plants and some bacteria fall into this category.
Getting their energy from the producers are the primary consumers, or herbivores. These are animals that eat plants. Deer and many insects are herbivores.
The next step in the chain are those animals that eat the herbivores, the carnivores. Also called secondary consumers, these animals are usually predators and strictly eat meat.
Since most organisms eat more than one thing, the belong to a series of food chains. When several food chains combine to show the transfer of energy in an ecosystem, it is called a food web. Connected to every food web are those organisms that break down the organisms that die. These are called the decomposers. Many types of fungi (i.e. mushrooms) and many species of bacteria break down dead organisms and reintroduce nutrients back into the soil so that new life can grow.
Directions for this Lesson: Answer the practice questions about ecosystem ecology and then watch the video to learn more.