The British anthropologists Louis S. B. Leakey, b. Aug. 7, 1903, d. Oct. 1, 1972, his wife, Mary, b. Mary Nichol, Feb. 6, 1913, and their son Richard, b. Dec. 19, 1944, have made major contributions to the study of human evolution. Louis and Mary Leakey investigated early human campsites at OLDUVAI GORGE, Tanzania, and found important hominid fossils more than 1.75 million years old. Their son Richard has conducted research in the East TURKANA area of Kenya and has discovered even earlier hominid fossils dating from as much as 3 million years ago. The son of a missionary in Kenya, Louis Seymour Bazett Leakey studied archaeology at Cambridge University from 1922 to 1926. He then returned to Kenya, where he investigated Stone Age cultures in East Africa, a pioneer field of research. From 1931 to 1959, Louis and his second wife, Mary, worked at Olduvai Gorge, reconstructing a long sequence of Stone Age cultures dating from approximately 2 million to 100,000 years ago. They documented the early history of stone technology from simple stone-chopping tools and flakes to relatively sophisticated, multipurpose hand axes. In 1959 the Leakeys discovered the skull of Australopithecus boisei (a species of the prehuman genus AUSTRALOPITHECUS). This skull was later dated at about 1.75 million years of age, using potassium-argon dating. The Leakeys also excavated another skull of a less robust individual in somewhat lower levels. Both new fossils were associated with stone chopping-tools. Louis Leakey claimed that the less robust hominid, which the Leakeys called HOMO HABILIS, was the earliest toolmaker and a direct ancestor of modern humans. Many scientists disagreed, largely because the fossil fragments were so small. By 1965 the Leakeys had found several other fossils at Olduvai, including a HOMO ERECTUS cranium that is about 1 million years old. Louis Leakey also experimented with techniques of making stone tools and attempted to understand how prehistoric hunter-gatherers obtained their food. He was a pioneer in primate research, encouraging such well-known social scientists as Jane GOODALL and Dian FOSSEY to study chimpanzees and gorillas. Leakey believed that such studies would increase understanding of early humans. After Leakey's death, Mary Leakey and their son Richard continued field research in East Africa. Mary Leakey did much of the fieldwork at Olduvai and has discovered Homo fossils more than 3.75 million years old at LAETOLI, located 40 km (25 mi) south of Olduvai. Richard Leakey has discovered more than 388 sq km (150 sq mi) of Lower Pleistocene deposits on the eastern shore of Lake Turkana (Rudolf) in northern Kenya. He found fragments of a more advanced hominid, known as SKULL 1470, which was dated by Leakey as 2.6 million years old. In 1984 he and his colleagues also found a nearly complete skeleton of a large H. erectus, dated as about 1.6 million years old. Kenya's government appointed Leakey as director of Wildlife Services in 1989, to help protect endangered elephants from ivory poachers. After months of turmoil, and a plane crash in which he lost both legs, he resigned in early 1994.
