Color enhanced illustration of Thomas Hunt Morgan (1866-1945), US geneticist and Nobel Laureate. Morgan was born in Kentucky, and studied zoology at the State College. He then moved to Johns Hopkins University. His work in genetics is largely remembered for the use of the fruit fly Drosophila melanogaster, and for establishing many ideas in chromosome theory. It was Morgan who proved that the chromosome was the carrier of heredity, and that the chromosome consists of genes. He also discovered crossover (the exchange of genes between chromosomes), and helped produce the first chromosome map. In 1933 he was awarded the Nobel Prize for Physiology or Medicine.