Theodosius Dobzhansky (1900-1975) was a pioneering Ukrainian-American evolutionary geneticist and one of the founding figures of the modern synthesis in evolutionary biology. His groundbreaking work "Genetics and the Origin of Species" (1937) revolutionized the integration of Mendelian genetics with Darwinian evolution. Through his research on Drosophila fruit flies, Dobzhansky demonstrated the genetic mechanisms underlying speciation and natural selection. His famous assertion that "Nothing in biology makes sense except in the light of evolution" became one of the most influential statements in science. He taught at Columbia University and the University of California, mentoring generations of geneticists and profoundly shaping 20th-century biology.
