Edmund Beecher Wilson

Edmund Beecher Wilson (October 19, 1856 – March 3, 1939) was a pioneering American zoologist and geneticist.

Wilson was born in Geneva, Illinois, and graduated from Yale in 1878. He earned his doctorate at Johns Hopkins in 1881.

He was a lecturer at Williams College in 1883-84 and at the Massachusetts Institute of Technology in 1884-85. He served as professor of biology at Bryn Mawr College from 1885 to 1891.

He spent the balance of his career at Columbia University where he was successively adjunct professor of biology (1891-94), professor of invertebrate zoölogy (1894-97), and professor of zoölogy beginning in 1897.

Wilson is credited as America's first cell biologist. In 1898 he used the similarity in embryos to describe phylogenetic relationships. By observing spinal cleavage in molluscs, flatworms and annelids he concluded that the same organs came from the same group of cells and concluded that all these organisms must have a common ancestor.

He also discovered the chromosomal XY sex-determination system in 1905 -- that males have XY and females XX sex chromosomes. Nettie Stevens independently made the same discovery the same year.

Professor Wilson published many papers on embryology, and served as president of the American Association for the Advancement of Science in 1913.

Works

 * An Introduction to General Biology (1887), with W. T. Sedgwick
 * The Embryology of the Earthworm (1889)
 * Amphioxus, and the Mosaic Theory of Development (1893)
 * Atlas of Fertilization and Karyokinesis (1895)
 * The Cell in Development and Inheritance (1896; second edition, 1915)