Artificial Selection and the Development of Ecologically Relevant Phenotypes

Artificial selection is used by quantitative geneticists to examine the genetic variances and covariances that underlie the evolution of traits that show continuous phenotypic variation. Such traits are crucial for adaptive evolution in natural populations. Here, I discuss the extent to which artificial selection experiments can provide insights about both the proximate and ultimate causes of adaptive evolution. In particular, such experiments can explore the basis of interactions among traits, and the potential consequences of genetic coupling of traits for the paths taken during evolution. They can also yield phenotypes of relevance to examining the reasons why differences in reproductive success and fitness occur. I focus here on the methodology, with particular reference to examples from investigations of the evolution of the development of morphologies and of phenotypic plasticity.