Keith, Arthur (1866-1955) was a Scottish anatomist and physical anthropologist who began his career as a physician. Keith was a leading authority on human fossils. He also made significant contributions to medical science and authored several books, including two anatomy textbooks. He was especially interested in early hominid forms and the question of where the human species originated. Until later evidence proved otherwise, he believed that human life originated in Europe.

Keith was born in Persley, Aberdeen, Scotland. He received his bachelor of medicine degree in 1888 from the University of Aberdeen. The following year he traveled to Siam (now Thailand) to work as a physician. There he became interested in primate anatomy. Upon his return to Britain in 1892, he began studying primate musculature, obtaining his M.D. degree from Aberdeen in 1894.

Turning more to physical anthropology, Keith studied early hominid development in Europe, North Africa, Israel, and Palestine. He thought that Europe would be found to be the birthplace of the human species and that modern humans descended from Neanderthals. By 1912, however, mounting archaeological evidence had forced him to alter his views on the course of human evolution. That same year, when fragments of a large skull and jawbone were found in Piltdown, in Sussex, England, and said to belong to a human, Keith's endorsement as a leading expert of the time lent credibility to the claim. But in 1953, the skull was determined to be only 200 years old, and the jawbone that of an orangutan. Many believed Keith had been involved in the hoax, as such a find would have lent credence to his theories. But his involvement was never proven and, perhaps because of his respected position in the scientific community, he avoided scandal. He was knighted in 1921 and spent his last 21 years as a researcher in Downe, England, once the home of Charles Robert Darwin.