English anthropologist and archaeologist.
Born Mary Douglas Nicol in London on 6 February 1913, Leakey was the only child of a landscape painter from whom she inherited a talent for drawing that was of considerable importance to her later career. Much travelling during her childhood disrupted her formal education but a visit to prehistoric caves in southwest France, where her father went to paint, kindled an interest in archaeology. A chance meeting with the archaeologist Dorothy Liddell in the late 1920s convinced her that a career in the subject was possible and she became Liddell's assistant, chiefly as the illustrator at a major dig at a Neolithic site in Devon. She met the anthropologist Louis Leakey at a dinner party and he invited her to illustrate a book he was then working on. She agreed, and the two began to work closely together. Mary Nicol travelled to join him in Kenya at the Olduvai Gorge, and after Louis Leakey's subsequent divorce, they married in 1936. Mary Leakey immediately began excavating a Late Stone Age site north of Nairobi, and with her husband discovered the remains of an important Neolithic settlement and many important artefacts.
During World War II Mary continued to develop research projects, and after the war she devoted much of her time to organizing a major Pan-African Congress of Prehistory and Palaeontology in 1947 with her husband. The success of that conference brought the work of the Leakeys to a wide audience. The attention continued in 1948 when Mary discovered, on Rusinga Island, Lake Victoria, the prehistoric ape skull known as Proconsul, about 20 million years old, and human footprints at Laetoli, to the south, about 3.75 million years old.
Over the following 15 years the Leakeys together and separately continued major excavations in Kenya, and accumulated evidence that East Africa was the possible cradle of the human race. By the middle of the 1960s Mary was living almost continuously at the permanent camp they had established at the Olduvai Gorge, whilst Louis was based in Nairobi and increasingly travelling around the world on lecture tours, and although they never officially separated, they lived apart until Louis's death in 1972. That event precipitated Mary onto the international stage and she became an accomplished lecturer and writer, while continuing to organize excavation work. She received several international awards and honorary doctorates, and published an account of her work Olduvai Gorge: My Search for Early Man (1979) and an autobiography Disclosing the Past (1984).