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Louis and Mary Leakey
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Site (Laetoli) where Mary Leakey found 3.5-million-year-
old footprints in 1976. Photo: Guston Sondin-Klausner
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Louis Leakey
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Mary Leakey (February 6, 1913 — December 9, 1996)
Louis Leakey (August 7, 1903 — October 1, 1972).
Two of the foremost fossil hunters of the 20th century, the Leakeys are known for their many discoveries relating to early human evolution. In particular, their finds at Olduvai Gorge, a site in northwestern Tanzania, when added to the prior work of Raymond Dart and Robert Broom, convinced most paleoanthropologists that humans originally evolved in Africa. For many years, especially after the discoveries of Homo erectus remains in China at
Zhoukoudian, the general belief had been that humans had come into being in Asia.
Louis began his work at Olduvai in 1931 and persisted searching there for early human remains under harsh conditions (see picture) for the next forty years. Much of his time was spent at the famous FLK site. An acronym for "Frida Leakey Korongo," it was named for his first wife (korongo is Swahili for gully).
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Paranthropus boisei
(click to enlarge)
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It was here in 1959 that Mary, his second wife, found remains of the robust australopithecine Zinjanthropus boisei (now known as Paranthropus boisei). Louis was in camp with a fever at the time. The specimen's age of 1.75 million years radically changed accepted ideas about the time scale of human evolution. They also found and studied more than 2,000 stone tools and flakes at the site. Louis Leakey's son Jonathan found the first specimen of Homo habilis, a jaw fragment, at Olduvai in 1960.
In 1948, on Rusinga Island in Lake Victoria, Mary also discovered a near complete skull of Proconsul, an apelike creature of Miocene age. Fossils attributed to this genus range from 27 to 17 million years in age. Animals of this type, in which no tail was present, mixed the traits of Old World monkeys and apes. A continuing controversy has existed over whether or not members of the genus Proconsul actually were apes. This is the view of some researchers. Others consider it a precursor of both Old World monkeys and apes.
Mary Leakey is also famed for her discovery of 3.5 million-year-old hominid footprints. The prints, which she found at Laetoli in Tanzania in 1974, were originally made in powdery volcanic ash laid down by an eruption of the nearby Sadiman Volcano. A light rain followed that cemented the ash without obscuring the prints, which were made by three individuals walking upright, possibly in a group. The footprints show that hominids even at that time walked upright — there are no knuckle-impressions like those of an ape. Nor do the feet have the mobile big toe of an ape. Rather, they have the same arched structure as those of modern humans. They are "perhaps the most remarkable find I have made in my entire career," she said in 1976.
When we first came across the hominid prints I must admit I was sceptical, but then it became clear that they could be nothing else. They are the earliest prints of man's ancestors, and they show us that hominids three-and three-quarter million years ago [the prints have since been more accurately dated to 3.5 mya] walked upright with a free-striding gait, just as we do today. [quoted in Milner (1993, p. 262)]
Mary Leakey originated many of the methods now widely used in the field. She was the more systematic and logical member of the pair. The intuitive Louis would pick a site on a hunch and she would follow through with a meticulous search, often while he was away abroad raising money. Although Louis was often credited with their discoveries in the popular press, and is the one usually pictured with their skulls (e.g., picture above), he never actually found a skull himslf. But she later said that if both of them had been the same sort of person, they would never have accomplished so much.
As part of his research into early humans Louis wanted to collect more information on the behavior of living apes. To this end, he selected two young women Jane Goodall and Diane Fossey — both now famous — to study, respectively, chimpanzees and gorillas in the wild.
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