[2] McKenzie suffered from a degenerative disease and while he slowly succumbed he assigned Hawley to teach a few of his classes.
While teaching Hawley printed the 1950 book Human Ecology, which had an international effect on the field of sociology.
[5][page needed] After concluding his travels, Hawley returned to the United States to teach at University of North Carolina, Chapel Hill as Sociology Professor (1966–1976).
Roderick McKenzie published several works on a number of topics ranging from immigration (Oriental Exclusion, 1927), economics ( L'evolution economique due monde, 1928), and to urbanism ( The Metropolitan Community, 1933).
[7] Hawley learned from Mckenzie that humans are observable units within an ecosystem with a given technology they will interact with their environment and develop predictable patterns.
Hawley contended that "the environment, population, and the ecosystem tend to move toward equilibrium" (Human Ecology, p. 10).
[8] By understanding the concepts behind population expansion and evolution, Hawley explored how all organisms are connected to the environment and through behavior.
Amos Hawley believed that organisms are connected in a web of relationships that interdependent and are enmeshed with the environment.
Hawley writes "thus the development of human dominance through the agency of culture involves a reconstruction of the biotic community.
Instead of accommodating his activities, as do primitive peoples, to the natural life association, civilized man regulates the biotic community in accordance with his needs".