Natural selection

Abstract

This chapter discusses the term natural selection as coined by Charles Darwin in his book “On the Origin of Species” in 1859. It reviews the precise scope and role of natural selection in evolutionary theory that generates many questions of philosophical interest. It divides the philosophical issues raised by natural selection into two rough categories: issues—such as the units of selection problem, and issues that include questions about the relationship between natural selection and other evolutionary processes. The chapter focuses on what is explained by natural selection, (adaptationism, forces and causes, and fitness). The chapter explains that an adaptation is a historical property rather than a comment about a trait's current utility. Maybe long necks are adaptive now because they help giraffes see over cars or buildings, but these are not reasons why the trait evolved. This central debate about adaptationism concerns the power and scope of natural selection. There is considerable disagreement, however, about the significance of non-selective factors such as random genetic drift and the role of mechanical, developmental, genetic, and other sorts of constraints. The debate about how to interpret natural selection, drift, and other factors will doubtless continue, especially since the disagreements depend in part on disputes about the nature of causation that lie in the background.