Each of several hierarchical levels in an ecosystem, comprising organisms that share the same function in the food chain and the same nutritional relationship to the primary sources of energy.
- ‘This high interannual variability at the base of the food chain influences organisms at all trophic levels.’
- ‘The transfer of energy from lower trophic levels to higher ones is inefficient so herbivores eat large quantities of plant material, and carnivores eat many times their body weight of prey during their lifetime.’
- ‘Other studies of omnivory have manipulated one trophic level, and have primarily been interested in the effects of omnivores on the lowest trophic level of a food chain or web.’
- ‘Reduced sea ice extent or the timing of sea ice formation and break-up will impact the lower trophic levels of the ecosystems upon which polar bears depend.’
- ‘Local extinctions of native species may occur at the invading species' own trophic level or at different trophic levels.’
We take a look at several popular, though confusing, punctuation marks.