Theodosius Dobzhansky

Born in 1900 in what is now Ukraine and later active in the United States, Theodosius Dobzhansky became one of the central figures in 20th-century evolutionary biology. He is especially known for helping unite Darwin’s theory of evolution with modern genetics, a major step in what came to be called the modern evolutionary synthesis.

His best-known book, Genetics and the Origin of Species (1937), brought together evidence from heredity, mutation, and natural populations in a way that influenced generations of biologists. Dobzhansky also carried out important research on fruit flies, using them to study genetic variation and evolution in real populations.

Beyond his technical work, he was admired for explaining science clearly and for arguing that biology makes the most sense when viewed through evolution. He died in 1975, but his ideas remain deeply woven into modern genetics and evolutionary theory.