Can natural selection explain why an individual has a particular trait, or can it only explain the prevalence of that trait in a population to which that individual belongs? In the late 1980s and 1990s Karen Neander and Elliot Sober debated this topic at length, Neander defending the former view and Sober the latter. The exchange was inconclusive, but much recent work in the philosophy of biology assumes that Sober was right. Here I revisit the Neander/Sober debate and consider its implications for current issues in the philosophy of biology.
