Howard Thomas Odum, usually cited as H. T. Odum, was an American ecologist. He is known for his pioneering work on ecosystem ecology, and for his provocative proposals for additional laws of thermodynamics, informed by his work on general systems theory.

George Evelyn Hutchinson was a British ecologist sometimes described as the "father of modern ecology." He contributed for more than sixty years to the fields of limnology, systems ecology, radiation ecology, entomology, genetics, biogeochemistry, a mathematical theory of population growth, art history, philosophy, religion, and anthropology. He worked on the passage of phosphorus through lakes, the chemistry and biology of lakes, the theory of interspecific competition, and on insect taxonomy and genetics, zoo-geography, and African water bugs. He is known as one of the first to combine ecology with mathematics. He became an international expert on lakes and wrote the four-volume Treatise on Limnology in 1957.