Wilhelm Ludwig and his contributions to population genetics.

This article reviews the life and work of the German biologist Wilhelm Ludwig (1901-1959), whose contributions to population genetics have been largely ignored. Ludwig's work was a rich tapestry of population biology, spanning investigations into population growth, biological asymmetries, sex ratio, and paternity analysis. He was ahead of his time in explicitly combining the theory of population ecology and population genetics. His classic paper on annidation showed the possibility of population differentiation in the face of gene flow, and his early studies demonstrated the importance of selection in evolutionary change. Much of his work spanned the period of the Second World War in Germany, and interesting questions remain about his life during this turbulent period.