Alan Grafen FRS is a Scottish ethologist and evolutionary biologist. He currently teaches and undertakes research at St John's College, Oxford. Along with regular contributions to scientific journals, Grafen is known publicly for his work as co-editor (with Mark Ridley) of the 2006 festschrift Richard Dawkins: How a Scientist Changed the Way We Think, honouring the achievements of his colleague and former academic advisor. He has worked extensively in the field of biological game theory, and, in 1990, devised a model showing that Zahavi's well-known handicap principle could theoretically exist in natural populations.