The Unfinished Business of the Darwinian Revolution

Judy Stone, professor of biology and Dr. Charles C. and Pamela W. Leighton Research Fellow, discusses the Darwinian Revolution. Darwin’s theories on descent with modification and on evolution by natural selection revolutionized biology. Both of these theories rest upon an underlying insight called population thinking, which recognizes that variation among individuals within a species is the key ingredient of evolution and adaptation. Population thinking is arguably Darwin’s most original insight because it overcomes thousands of years of typological thinking, in which variation is considered to be imperfection around the true type. Unfortunately, despite Darwin’s brilliant insight, typological thinking persists in biology, medicine, journalism, and the public mind. Typological thinking can lead to erroneous and even dangerous conclusions, especially when applied to the human species. Cutting-edge approaches in genomics have the potential to finally complete the Darwinian paradigm shift so that the complexity of variation is fully appreciated.