"Many of the original and innovative contributions to the field of urban sociology came out of the University of Chicago in the early 20th Century. Influenced by the natural sciences, in particular evolutionary biology, members of the Chicago School forwarded an ecological approach to sociology emphasizing the interaction between human behavior, social structures and the built environment. In their view, competition over scarce resources, particularly land, led to the spatial differentiation of urban areas into zones of similar use and similar social groups.
Two of the major proponents of urban ecology were Ernest Burgess and Robert E. Park, professors at the University of Chicago, who together in 1925 published a book entitled The City."
Many students struggle with models when there isn't a corresponding example. The Concentric Zone Model and Chicago are a great marriage.