Kuhn (1962) proposed an evolutionary model to explain how scientific knowledge is built, based on the concept of paradigm. Even though Kuhn’s model is general, it has been applied to only a few topics in evolutionary biology, almost exclusively to broad-based paradigms. We analyze here, through the lens of Kuhn’s theory, a small-scale paradigm change that occurred with the resolution of the controversy about the mating system of a Mediterranean shrub Phillyrea angustifolia (Oleaceae). We first summarize the different steps of (...) the paradigm change and replace them in the more general context of sex ratio theory. Second, we show how the different steps of the paradigm change can be interpreted by Kuhnian concepts and tools. Finally, we discuss the actual and future status of the new paradigm. (shrink)