Theodosius Dobzhansky (January 25 1900-November 11 1975), a famous geneticist, was born in Ukraine (then part of Russia), but lived in the United States beginning in 1927.
He taught at the California Institute of Technology (1930-1940) and Columbia University (1940-1962).
He did much important genetic research, mainly on various species of Drosophila.
His most famous saying was "Nothing in biology makes sense except in the light of evolution".
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