REDUCING BIAS IN THE MEASUREMENT OF SELECTION

Selection on quantitative characters is commonly measured in natural p opulations using regression techniques based on phenotypic covariances between traits and fitness. However, such methods do not give an accu rate view of the causal relationship between the phenotype and fitness if environmental factors also contribute to covariances between trait s and fitness. A recently developed method for estimating selection el iminates the problem of bias resulting from environmental covariances. This underappreciated method represents a significant addition to the toolbox of the evolutionary ecologist.