Ecosystem
The term ecosystem was first used in 1935 in a publication by British ecologist Arthur Tansley. Tansley devised the concept to draw attention to the importance of transfers of materials between organisms and their environment. He later refined the term, describing it as "The whole system, ... including not only the organism-complex, but also the whole complex of physical factors forming what we call the environment". Tansley regarded ecosystems not simply as natural units, but as "mental isolates". Tansley later defined the spatial extent of ecosystems using the term ecotope.
Human ecology
The term "human ecology" was published in 1907 in Ellen Swallow Richards work "Sanitation in Daily Life", defined there as "the study of the surroundings of human beings in the effects they produce on the lives of men". Richard's use of the term recognized humans as part of rather than separate from nature. The term made its first formal appearance in the field of sociology in the 1921 book "Introduction to the Science of Sociology", published by Robert E. Park and Ernest W. Burgess (also from the sociology department at the University of Chicago). Their student, Roderick D. McKenzie helped solidify human ecology as a sub-discipline within the Chicago school. These authors emphasized the difference between human ecology and ecology in general by highlighting cultural evolution in human societies.