Neodarwinism is synonymous with the Modern Synthesis, which occured over the latter half of the 20th century. This explosive development of evolutionary biology was founded by the original trinity of biologists: Sewall Wright, Ronald A. Fisher and J. B. S. Haldane. Their combined work largely determined the theoretical foundation of the next decades' work on evolution, as well as making substantial contributions to fundamental statistics and biochemistry. The four evolutionary forces -- selection, mutation, gene flow and genetic drift -- were finally integrated into a rigorous quantitative framework.

Since then the Modern Synthesis has busied itself in further theoretical development and empirical research within this framework. Motoo Kimura and G. Malécot sustained the mathematical development of evolutionary processes, and Theodoseus Dobzhansky, Ernst Mayr, James Crow among many others made further contributions in experiment and theory. This extensive literature includes the investigation of speciation processes, genetic load, molecular evolution and systematic biology.