Phenotypic selection in natural populations: what have we learned in 40 years?

In 1983, Russell Lande and Stevan Arnold published "The measurement of selection on correlated characters," which became a highly influential citation classic in evolutionary biology. This paper stimulated a cottage industry of field studies of natural and sexual selection in nature and resulted in several large-scale meta-analyses, statistical developments, and method papers. The statistical tools they suggested contributed to a breakdown of the traditional dichotomy between ecological and evolutionary time scales and stimulated later developments such as "eco-evolutionary dynamics". However, regression-based selection analyses also became criticized from philosophical, methodological, and statistical viewpoints and stimulated some still ongoing debates about causality in evolutionary biology. Here I return to this landmark paper by Lande and Arnold, analyze the controversies and debates it gave rise to and discuss the past, present, and future of selection analyses in natural populations. A remaining legacy of Lande & Arnold, 1983 is that studies of selection and inheritance can fruitfully be decoupled and be studied separately, since selection acts on phenotypes regardless of their genetic basis, and hence selection and evolutionary responses to selection are distinct processes.