cave system, about 12km north of Krugersdorp in Gauteng, is the site of some of
the most important discoveries concerning human evolution. The limestone
deposit at the surface, from which the first fossils were recovered, was formed
by the collapse and infilling of a cavern as it became exposed by erosion.
Underlying the old quarry is an extensive system of younger caves containing an
underground lake and many limestone formations, part of which is open to
Research Unit at the Unitversity of the Witwatersrand has been excavating at
Sterkfontein continuously since 1968, and more than 550 hominid fossil specimens
have been found. For the year 'Mrs Ples' was the best specimen of A. africanus.
However, towards the end of 1998, an entire australopithecine skull together
with its skeleton was discovered by Dr Ron Clarke, in an underground cavern
beneath the surface excavations. Owing to its great age (between about 3.2
and 3.5 million years) and completeness, this is regarded as the most important
fossil find in South Africa since the Taung skull.