Where sea otter populations have lingered ... of natural resource management is that forcing functions across trophic levels are considered largely bottom-up in nature (Estes & Peterson 2000).

Sea levels were higher at the time, and much of the area was covered by a warm, shallow sea. That sea apparently bustled with life at all trophic levels, the study's authors note, part of a ...

Otodus megalodon has been revealed by new research to have occupied a higher position on the food chain—known as its trophic level—than any other ocean predator, living or extinct. That puts Megatooth ...

Stable isotopes have helped uncover migratory routes, trophic levels, and the geographic origin of migratory animals. They can be used on land as well as in the ocean and have revolutionized how ...