The first revival of competition theory
The theoretical approach to understanding competitive systems, initiated by Lotka and Volterra, was not advanced significantly in the biological literature until a young professor of biology at Princeton University, Robert MacArthur, revived interest in mathematical studies of competition in the 1960s and early 1970s.
Richard Levins (1968) independently stressed the importance of resources for understanding competition, and, in joint work, these two authors tried to relate competition between species to their similarity in resource use. MacArthur’s final (1972) book, Geographical Ecology contained a large section that was devoted to interspecific competition. Two years earlier he had published an article on this topic, which was the very first article in the first issue of a new journal, Theoretical Population Biology. Both works analysed the conditions allowing competing species to coexist. They proposed a general relationship between overlap in the two spectra of resource capture rates by two consumer species, and the resulting competition coefficient describing the relative strengths of inter- and intraspecific effects of abundance on per capita growth rate. The main innovation in these works was to examine the consistency of the LV model with more detailed mathematical models that contained descriptions of both resource and consumer dynamics. The per capita growth rates of all species were linear functions of the variables affecting growth. MacArthur’s main conclusion was that these models were consistent with the LV model. Unfortunately, MacArthur had already published several influential works using the LV model, so his assessment of the ability of that model to reflect resource dynamics was somewhat biased. MacArthur’s career was tragically cut short by cancer in 1972, but competition continued to be one of the main topics within theoretical ecology for the rest of that decade.For some later authors, MacArthur’s work seemed to justify continuing studies of the LV model, or closely related forms that lacked resources. For others, his work was an indication that relationships with resources were a key to understanding some competitive systems. This contradiction has persisted until the present time in part because research on competition fell out of favour for a decade or more at the end of the last century. In his 1997 book on competition, James Grover (p. 277) wrote, About fifteen years ago, the study of competition seemed moribund, if not dead’.
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