Thomas H. Morgan

Thomas Hunt Morgan (September 25, 1866 – December 4, 1945) was an American evolutionary biologist, geneticist and embryologist and science author who won the Nobel Prize in Physiology or Medicine in 1933 for discoveries elucidating the role the chromosome plays in heredity.

Morgan received his PhD from Johns Hopkins University in zoology in 1890 and researched embryology during his tenure at Bryn Mawr. Following the rediscovery of Mendelian inheritance in 1900, Morgan's research moved to the study of mutation in the fruit fly Drosophila melanogaster. In his famous Fly Room at Columbia University, Morgan demonstrated that genes are carried on chromosomes and are the mechanical basis of heredity. These discoveries formed the basis of the modern science of genetics.

During his distinguished career, Morgan wrote 22 books and 370 scientific papers. As a result of his work, Drosophila became a major model organism in contemporary genetics. The Division of Biology which he established at the California Institute of Technology has produced seven Nobel Prize winners.

In 1890, Morgan was appointed associate professor (and head of the biology department) at Johns Hopkins' sister school Bryn Mawr College, replacing his colleague Edmund Beecher Wilson.

 Morgan taught all morphology-related courses, while the other member of the department, Jacques Loeb, taught the physiological courses. Although Loeb stayed for only one year, it was the beginning of their lifelong friendship.

Morgan lectured in biology five days a week, giving two lectures a day. He frequently included his own recent research in his lectures. 

Although an enthusiastic teacher, he was most interested in research in the laboratory. During the first few years at Bryn Mawr, he produced descriptive studies of sea acorns, ascidian worms and frogs.

Morgan was interested in evolution throughout his life. He wrote his thesis on the phylogeny of sea spiders (pycnogonids) and wrote four books about evolution.

 In Evolution and Adaptation (1903), he argued the anti-Darwinist position that selection could never produce wholly new species by acting on slight individual differences.

 He rejected Darwin's theory of sexual selection^[24] and the Neo-Lamarckian theory of the inheritance of acquired characters.