Cradle of Humankind
Known in South Africa as the Cradle of Humankind, the region of Sterkfontein, Swartkrans, Kromdraai and envorins has one of the world's richest concentrations of hominid fossils, evidence of human evolution over the last 3,5 million years.
Located in the Gauteng and North West provinces, the site compromises of a strip of a dozen dolomitic limestone caves containing fossilised remains of ancient forms of animals, plants and most importantly hominids. The dolomite, in which the caves formed, started out as coral reefs growing in a warm shallow sea about 2, 3 billion years ago.
This site was inscribed in 1999 and covers an area of 47 000 hectares. Although other sites in south and east Africa have similar remains, the Cradle has produced more than 950 hominid fossil specimens.
As the coral reefs died off through the years, they were transformed into limestone which some time later was converted into dolomite. Millions of years later after the sea had receded, slightly acidic groundwater began to dissolve out calcium carbonate fro the dolomite to form underground caverns. Over time the water table dropped and the underground caverns were exposed to the air. The percolation of acidic water through the dolomite also dissolved calcium carbonates out of the rock into the caverns, which formed stalactites, stalagmites and other crystalline structures. Continued erosion on the earth's surface and dissolution of the dolomite eventually resulted in shafts or avens forming between the surface of the earth and the caverns below. Bones, stones and plants washed down these shafts into the caves; and animals and hominids fell into the caves, became trapped and died. The bone and plant remains became fossilised and along with various stones and pebbles became cemented in a hard mixture called breccia.
At least seven of the twelve sites have yielded hominid remains. The scientific value of this area lies in the fact that these sites provide us with a window into the past, to a time when our earliest ancestors were evolving and changing. Scientists have long accepted that all humans had their origins in Africa.
Sites in the area supply crucial information about members of one of the oldest hominids, the australopithecines - two-footed, small-brained primates that appeared about 5 million years ago.
Excavations and research at the Sterkfontein Caves have so far yielded the nearly complete skeleton of a 3,3 million year old australopithecine, as well as about 500 specimens of Australopithecus africanus that date from about 2.8 to 2.6 million years ago.
Other major finds in the area include the most complete skull yet found of Australopithecus africanus, an outstanding example of a female Paranthropuss - a more robust australopithecine, also known as Australopithecus robustus - and fossils of an early species of the genus Homo with stone tools, the first evidence of cultural behaviour.
The new Sterkfontein Cave visitors' centre, the first phase of a multimillion rand development at the Cradle of Humankind outside Johannesburg, is now complete, offering a richer experience at one of the world's most important archaeological sites.
A guided tour of the cave, which descends 60 meters underground, is an exceptional part of the experience. There is so much to see and do at the site. Sterkfontein Cave is the most famous of 13 excavated fossil sites in the broader 47 000 hectare Cradle of Humankind site. Three million years of human activity have taken place in and around the Cradle, including man's earliest-known mastery of fire.
Forty percent of all human ancestor fossil finds have been made here, including several of the world's most famous and important fossils - among them Mrs Ples (now believed to be Mister Ples), dating back 2.5-million years, and Little Foot, an almost complete ape-man skeleton between 3 and 3.5-million years old (though a recent study puts it at just over 4-million years old).
This is the longest palaenthological dig in the world and excavations will probably continue for another 100 years! It will become a major attraction for both local and international visitors - a celebration of human development.