Raymond Laurel Lindeman, Ecological Dynamics in a Senescent Lake (Ph.D. Thesis, University of Minnesota, 1941).

In his doctoral thesis, Raymond Lindeman developed the "trophic dynamic" approach that would be so influential to the formation of ecosystem ecology in his widely cited "The Trophic Dynamic aspects of Ecology" (1941). For his thesis, he (and his wife Eleanor) conducted a comprehensive analysis of the "food relations" of Cedar Bog Lake outside of Minneapolis, MN. Like in the Chinese proverb that he cited:

"Large fish eats small fish;
Small fish eats water insects;
Water insects eat plants and mud."

Lindeman paid attention to the community relations that has become central to limnology (the study of lakes) and ecology (the study of communities). He expanded a number of previous works, e.g. F. A. Forel's "Le Leman" (1892), which studied the general nature of food cycles into a a study of trophic equilibrium and its relationship to succession and climax formation.

Lindeman's diagram "The primary food-cycle of Cedar Bog Lake," shows how nutrients are incorporated into organic substances by three agencies: autotrophic bacteria, algae, and pondweeds. Each of these may die and decompose by bacterial action into ooze, or may be eaten by some animal. These nutrients then move around the food cycle depicted.