Predicting the evolutionary consequences of trophy hunting on a quantitative trait

Some ecologists suggest that trophy hunting (e.g., harvesting males with a desirable trait above a certain size) can lead to rapid phenotypic change, which has led to an ongoing discussion about evolutionary consequences of trophy hunting. Claims of rapid evolution come from the statistical analyses of data, with no examination of whether these results are theoretically plausible. We constructed simple quantitative genetic models to explore how a range of hunting scenarios affects the evolution of a trophy such as horn length. We show that trophy hunting does lead to trophy evolution defined as change in the mean breeding value of the trait. However, the fastest rates of phenotypic change attributable to trophy hunting via evolution that are theoretically possible under standard assumptions of quantitative genetics are 1-2 orders of magnitude slower than the fastest rates of phenotypic change reported from statistical analyses. Our work suggests a re-evaluation of the likely evolutionary consequences of trophy hunting would be appropriate when setting policy. Our work does not consider the ethical or ecological consequences of trophy hunting. (c) 2017 The Wildlife Society. We show that the widely cited results claiming rapid evolution of trophy size in bighorn sheep in response to selective trophy hunting are theoretically impossible given standard assumptions of quantitative genetics.