Abstract

Cultural displays, such as art and science, are proposed to be used by males to compete for potential mates. As a result, the desire to engage in such behaviours will diminish following marriage. Male competition in sport can be considered a cultural display for potential mates, therefore male sporting performance will be negatively affected by marriage. Here we show that professional male tennis players perform significantly worse in the year after their marriage compared to the year before, whereas there is no such effect for unmarried players of the same age. Therefore the results suggest that following marriage, males experience an evolved psychological mechanism that leads to less motivation to engage in intra-sexual competition. Fluctuating testosterone (T) levels are discussed as providing the underlying biochemical changes necessary for such mechanisms.