Late in life (1871), Darwin published The Descent of Man. In it, he said that Africa was the cradle of mankind. Nevertheless, Asia seemed then to be the likely place of human origins. Evidence from Africa would not appear until the 1920s, but let us return to the 1890s and the search in Asia.
II. EUGENE DUBOIS (1853-1940)
Born in Holland and trained as a physician, Dubois became a teacher of anatomy. He had a passion to find 'the missing link', named even before its discovery, as pithecanthropus (ape-like man). The tropics of Indonesia seemed a logical choice: it was home to the orangutan, the so-called 'man of the forest.' The only hominid fossils known at that time were the Neandertals from Europe, and they were disputed. Dubois wanted to go to Asia.
How could he get there? The Dutch East Indian Army was in Sumatra, then a colony of Holland. Dubois signed on as a medical officer. Two years after his arrival, he convinced authorities to assign him convict labor. On the banks of the Solo river, he found a tooth, skullcap, and a femur and christened his finds as Java man, the 'missing link.' His claims in 1890 drew scorn and disbelief. Stung and angered, he hid his skeletal remains under his dining room floorboards, not releasing them from their confinement until 1923. He carried the prize tooth on his key ring for many years. 'Java man' and subsequent contemporaneous China finds are recognized today as Homo erectus, 'upright man.'
III. RAYMOND DART (1893-1988) AND ROBERT BROOM (1866-1951).
In 1922, the young Australian anatomist Raymond Dart traveled with his American wife to South Africa to assume the role of professor of anatomy. Yet, he had a keen interest in human origins and asked his students to bring in any fossils they might find. Through one of his students he became acquainted with the quarry master at Taung, a commercial limestone quarry.
One day in 1924, two crates of fossils from Taung quarry were brought to Dart. Out of one rolled an endocast of a small brain. His curiosity aroused, he found the matching skeletal fragment. Without laboratory or equipment, he painstakingly removed the limestone with his wife's knitting needles. What emerged was a fossil, with deciduous teeth that were surprisingly humanlike.
In a daring leap of intuition, he perceived his find as the upright ancestor of humans and called it Australopithecus (ape from the south). Within four months, he published his findings and conclusions in Nature, but was soon rebuked by the anthropological establishment of that time.
Could humans have originated in Africa? Never! They had one link already, Pithecanthropus from Asia. Furthermore, there was Piltdown from England--a further refutation of Dart. Shortly after publication in Nature, however, Dart acquired an ally.
Robert Broom was a Scottish physician and was 30 years older than Dart. Himself a recognized authority on reptilian fossils, he wrote to Dart and asked to see 'his distinguished ancestor.' Upon arrival at Dart's home in Johannesburg, he knelt at the edge of the table with the fossil. When asked what he was doing, he replied 'I behold my ancestor!' The subsequent friendship between the two men lasted the rest of their lives.
Dart, having become dean of the medical school, no longer had time for fieldwork. Broom meanwhile could not begin a systematic search until 1936. Now in his seventies, a brilliant and methodical paleontologist, he began the search in South Africa for the adult form of the Taung juvenile. Broom had a distinctive field style: under the hot blazing South African sun with temperatures in the nineties, he wore a business suit, tie, and a starched white shirt.
Broom went on to become the most successful hominid fossil hunter of all time. He found more hominid fossils than all other fieldworkers combined. With persistence, luck, and superb analytical skills, he produced the 'smoking gun' to prove Dart was correct about African human origins. Broom was very successful in finding adult specimens. His work was interrupted for a time by the war. In 1947 he found an exceptional cranium with jaws affectionately known as 'Mrs. Plez.'
Two types of Australopithecines were recognized by Broom: a smaller 'gracile' form and a larger 'robust' form, a distinction still accepted today. A visit by William King Gregory to Africa lent support to Broom's conclusions and led to acceptance of Australopithecines by the anthropological community. After World War II, Dart received a letter of apology from Sir Arthur Keith for the earlier criticisms of Dart's announcement in 1924.
Raymond Dart returned to fieldwork in 1947 and lived long enough to receive the acclaim so long denied to him. One hurdle remained for acceptance of the Australopithecines as ancestral to modern humans and older than any hominids from Asia.
IV. THE LEAKEYS, A MOST REMARKABLE FAMILY
The Leakeys have been prominent and colorful figures in paleontology and Kenya for almost a century. They have contributed mightily and have inspired a generation of investigators, among them Jane Goodall, Dian. Fosse, and Birute Galdaikis. Don Johanson has acknowledged that his determination to study human origins began with news reports about discoveries at Olduvai while in high school
Larger than life, Louis Leakey (1903-1972) was the son of British missionaries--and was probably was one of the first white children born in East Africa. His early training was in the African bush (he was initiated into the Kikuyu tribe), but he later went to England for a formal education and in time received a degree from Cambridge.
Louis began his work at Olduvai in East Africa in 1931; he was joined in the field by Mary Leakey in 1935. In the next 40 years, with a combination of energy, optimism, persistance, he and Mary made many significant finds, notably the fossil of a tool user which they christened Homo habilis. His unwavering insistence that Africa was the cradle of humanity has won universal acceptance.
Mary Nicol Leakey (1913-1996) who lived in the shadow of her famous husband, actually made the most significant archaeological finds. In 1948 she found the best preserved Proconsul skull ever discovered. It was Mary who found "Zinj" (A. boisei) in 1959 and, most stunning of all, the footprints of A. afarensis at Laetoli in 1978.
She was always the supervisor of archaeological work at Olduvai while her famous husband was busily engaged in traveling, lecturing, and managing the National Museums in Nairobi.
Her son Richard Leakey (1944- ) and his wife Meave have made important contributions to the field. Among Richard's major finds are further evidence of Homo habilis and with Alan Walker, the 'Turkana Boy', a 1.6 million year old skeleton of an adolescent Homo erectus. Richard has survived a kidney transplant and the loss of both legs below the knees after a plane crash.
Meave Leakey and their eldest daughter Louise handle most of the fossil work. She made world headlines with the release of a description of A. anamensis in 1995.
V. AN INFAMOUS FRAUD
Piltdown, mentioned earlier, had emerged from a British gravel pit in 1911 and was a problem from the start. It had a primitive ape-like jaw, but a large modern cranium. It 'fit' the expectation of the time. Australopithecines were the reverse: modern jaw, small brain and early in the century didn't 'fit in' with the prevailing ideas. In 1950, fluorine dating was used to show that Piltdown was a fraud: a fairly modern cranium hooked up with an orangutan mandible conveniently altered to look ancient.
'Who dunnit' has been speculated for many years. Very recently, a lab drawer in the British museum has provided telling evidence. That drawer belonged to a disgruntled laboratory worker, Martin Hinton. The drawer contained many skeletal materials 'doctored' in the same way.
The acceptance of the Australopithecines paved the way for field work by Don Johanson, the Leakey family and others. Today Africa is considered the cradle of humanity and it appears now that we are all Africans . . . every one of us.
..... CJ 99
Campbell, B. and Loy, J. Humankind Emerging 7th ed. New York: HarperCollins Publishers Inc., 1996.
Leakey, R. and Lewin, R. Origins Reconsidered In Search of What Makes Us Human. New York: Doubleday, 1992.