Secondary production of species in multi-species assemblages can be used to quantify bottom-up linkages with flow webs, top ... level 2 and trophic position 2. Trichopterans, however, obtain their ...

Trophic cascades by definition must occur across a minimum of three feeding levels ... are not limited by food availability as historically thought, but rather by strong top-down control.

Predators are found at the top of a food ... producer in this food chain. Its bar goes at the bottom of the pyramid. Energy is lost to the surroundings as we go from one level to the next, so ...

food chains do not show the number of organisms at each trophic level. Pyramids of number are not always perfect pyramids because of large organisms at the bottom and small ones at the top.