Communities & Ecosystems


Primary Productivity
Population Dynamics
Biome Project

Ecology Information

Trophic Levels
Predator & Prey

Communities & Ecosystem Sites

Trophic Pyramids and Food Webs
Food Web
Ecological Pyramids
Food Chains
Why most systems typically have only 3-4 trophic levels
The Flow of Energy
Steam Biology
A Simple Dictionary Of Common Terms. Rainforest Ecology and Food Web


Henderson's Dictionary of Biological Terms, by Eleanor Lawrence. 10th Ed.


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Communities & Ecosystems


Trophic Levels

Trophic levels defines the general path of nutrients through an ecosystem's community. This is one aspect of how populations in an ecosystem interact, their predator and prey interactions. An ecologist assembling a web showing which organisms eat or are eaten by another species will be able to look at this food pyramid. A food pyramid places all of the producers (plants) within an ecosystem at the bottom of this pyramid, the first level. On the second level of this pyramid who will find the ecosystem's herbivores, those animals that eat plants. Just above this level, at the third level of the food pyramid, the first predators, the primary carnivore, lie. They are the animals eating the herbivores. If the ecosystem can support it, you may find yet a fourth level, where a secondary carnivore eats the primary carnivore. The secondary predator is not restricted to eating the primary carnivore, but they may also eat herbivores. If this ecosystem does not have another level on the food pyramid, then the secondary carnivore may be called the top predator.