Leakey was born in London a century ago today, to Cecilia Marion Nicol and Erskine Edward Nicol, a landscape painter. According to the website of the Leakey Foundation, she showed artistic talent from an early age. She also traveled with her family across Europe and to sites such as the caves Pech Merl in Dordogne, in Southwest France. By the time she was 17, the Leakey Foundation reports, she was already working as an illustrator on digs in the UK.
In the mid-1930s, she was introduced to Louis Leakey, an older archaeologist. Louis Leakey wanted Mary to illustrate a book of his; they fell in love and married in 1937.
In subsequent years, Leakey traveled frequently across the Serengeti, where she and Louis led a number important excavations. The find that made Mary's name came in 1959, with the discovery of the Zinjanthropus bosei fossil – later reclassified as Australopithecus boisei – in Olduvai Gorge, Tanzania. The fossil, a mostly-intact cranium, helped scientists better understand human evolution, and also the importance of East Africa to the origins of humanity.