Related Experiment Video
Updated: Jun 5, 2026
12:24
Laboratory Estimation of Net Trophic Transfer Efficiencies of PCB Congeners to Lake Trout (Salvelinus namaycush) from Its Prey
Published on: August 29, 2014
The decline of the trophic level concept
1Steve Cousins is at the Energy and Environment Research Unit, The Open University, Milton Keynes, MK7 6AA, UK.
Trends in Ecology & Evolution
|January 14, 2011
Summary
The trophic level concept in ecology has limitations as a predictive model. Research reviews its failures and modifications, favoring taxonomic food web analysis for better ecological insights.
Area of Science:
- Ecology
- Food Web Dynamics
- Ecological Modeling
Background:
- The trophic level concept is a foundational ecological model.
- Its predictive power in complex ecosystems has been questioned.
- Previous research has explored its limitations and potential revisions.
Purpose of the Study:
- To describe the historical development of the trophic level concept.
- To examine the reasons for its inadequacy as a predictive ecological model.
- To review proposed defenses and modifications of the concept.
Main Methods:
- Literature review of ecological studies on trophic levels.
- Analysis of historical ecological modeling approaches.
- Identification of trends in food web analysis.
Main Results:
- The trophic level concept has limitations in predicting ecological interactions.
- Modifications and defenses of the concept have been proposed.
- A shift towards taxonomic food web analysis is evident.
Conclusions:
- The trophic level concept's predictive utility is limited.
- Taxonomic food web analysis offers a more robust alternative.
- Future ecological models may move beyond the traditional trophic level approach.
Related Concept Videos
01:35Trophic Levels
All organisms in an ecosystem occupy a trophic level in the food chain. The lowest level consists of primary producers, which synthesize their food from either solar or chemical energy. Each subsequent level obtains energy from the levels below. Detritivores can occupy any of the levels above primary producers.
00:46Trophic Efficiency
Trophic level transfer efficiency (TLTE) is a measure of the total energy transfer from one trophic level to the next. Due to extensive energy loss as metabolic heat, an average of only 10% of the original energy obtained is passed on to the next level. This pattern of energy loss severely limits the possible number of trophic levels in a food chain.
02:07Conservation of Declining Populations
Conservation of declining population focuses on ways of detecting, diagnosing, and halting a population decline. The approach uses methods to prevent populations from going extinct.
01:50Threats to Biodiversity
There have been five major extinction events throughout geological history, resulting in the elimination of biodiversity, followed by a rebound of species that adapted to the new conditions. In the current geological epoch, the Holocene, there is a sixth extinction event in progress. This mass extinction has been attributed to human activities and is thus provisionally called the Anthropocene. In 2019 the human population reached 7.7 billion people and is projected to comprise 10 billion by...
01:09Levels of Organization
Biological organization is the classification of biological structures, ranging from atoms at the bottom of the hierarchy to the Earth's biosphere. Each level of the hierarchy represents an increase in complexity that builds upon the previous level.Molecules Are Composed of Atoms, and Biomolecules Are Assembled from Molecules:The most basic levels include atoms, molecules, and biomolecules. Atoms, the smallest unit of ordinary matter, are composed of a nucleus and electrons. Molecules comprise...
01:30Marine Microbial Ecology
Marine microbial ecosystems are shaped by distinct physicochemical limits, including high salinity, low nutrient availability, and fluctuating oxygen levels. These conditions favor smaller microbial cell sizes, which maximize their surface-to-volume ratio for efficient nutrient uptake.Microbial activity and community composition are closely linked to biogeochemical cycles, particularly in dynamic environments like estuaries, where halotolerant microbes thrive in response to variable salinity...