A reassessment of the work of Fisher, Haldane, Muller and Wright on the occasion of the centenaries of their birth. Given the seminal role played by these figures in 20th-century evolutionary biology, it is also an important contribution to the history of biology. It brings together the scholarship of biologists, historians and philosophers to analyze the relative contributions and influence of these figures. In considering Mulle r along with Fisher, Haldane and Wright as a founder of "evolutionary genetics", the book breaks new ground in the historiography of biology. The contributions included here should be of value to evolutionary biologists as well as historians and philosophers of science. The book should also appeal to evolutionary biologists and historians and philosophers of biology.