"Mrs. Ples" Sterkfontein, 1947
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One day in the early 1920s, a worker at a limestone quarry in the town of Buxton (near Kimberly, South Africa) came across a skull.  It was not the first fossil discovered at the worksite; in fact, the quarry's collection of rocks embedded with old bones was growing.  It was, however, the first piece to be examined in detail.  Nobody realized it at the time, but, in addition to its commercial value, limestone also holds a wealth of history.  Limestone is a sedimentary rock, meaning it is formed in layers over hundreds of thousands of years. Anything caught within a given sedimentary layer, is encased in air-and water-tight cement,  making limestone an effective preservative of both animal and mineral fossils.

Early Homo Sapiens (reconstruction)
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The skull made its way to Dr. Raymond Dart, professor of Anatomy at the nearby University of Witwatersrand who recognized it as a fossilized baboon skull.  Since limestone was the source of human fossils discovered in Zambia in 1921, Dart decided to investigate further.  He received a parcel from the quarry of pieces discovered over the years.  Among the pieces, two in particular caught Dart's eye.  One was a skull--encased in limestone--which seemed to have an uncanny fit with a second piece--a limestone chunk with a visible, broken jaw.

After several years of careful work, Dart removed the limestone shell to reveal the nearly intact face of a juvenile hominid (early human).  He published his research in 1925,  identifying the find as an extinct ape with physical characteristics found in both modern apes and modern humans.  Although people would come to refer to his discovery as an "ape-man", Dart called his discovery Australopithecus (or "Southern Ape").

Australopithecus Africanus
"Taung Child", 1924

Few took notice of what would be popularly called the "Taung Child".  It took nearly two decades of further research and mounds of supporting evidence before the scientific community even accepted his findings as legitimate.  It would take an additional 35 years before Australopithecus was accepted as a relative of humans.  There are numerous reasons for this reluctance: cultural/religious biases prevented some from believing "advanced" or "modern" humans could evolve from a "primitive" creature found on a "primitive" continent.  In addition, earlier finds were often misinterpreted as solely ape or solely human, setting a flawed baseline to which future discoveries would be compared.  Finally, since technological limitations prevented accurate dating, it was difficult to establish a timeline in the historical record.

There was also at least one famous hoax which led researchers to the wrong conclusions and probably made others more cautious about legitimate finds.  The Piltdown skull, found in 1914 in England was presented as the definitive example of an early human fossil.  It offered a large, modern brain cavity and a primitive mouth; the exact opposite of australopithecus.  It would remain a point of reference for 40 years until chemical tests proved it to be a fraud: a recent human skull combined with a tampered orangutan jaw.

Nevertheless, the Taung Child represents the birth of the study of hominids--our earliest ancestors.  Subsequent research revealed several types of australopithecus as well as an additional species called paranthropus.  This discovery was important for several reasons:  First, it helped establish evolution as a legitimate scientific discipline.  Early modern human remains were discovered as early as 1829 (homo neanderthalensis, Belgium), but none provided the critical link between apes and humans (the very concept remains a point of contention to this day).  Secondly, general scientific thought held that modern man evolved in Europe and Asia.  African populations were considered to be "primitive" and therefore too young to be the origin of modern humans.  This discovery established Africa's importance in human history and forced the re-evaluation of many cultural and racial prejudices.  For the next 80 years, scientists would scour the African continent for signs of earl hominids and human development.  For more information about these early hominids, follow the links below.