Beneath South Africa's surface, history is marked by bones and stones
Sunday, May 23, 2010
The empty eye sockets of the battered half-skull stared at me, lifeless, sightless and silent. They were topped by a heavy brow ridge of bone, and the upper jaw of the creature's broad face jutted forward. Not fully human but recognizably related, it sent a shiver down my spine as I looked across 12 inches of space and 2 1/2 million years in time.
There is something deeply humbling about coming face to face with one of humanity's distant early relatives, a practical demonstration of one's own utter insignificance as an individual.
Stw 505 does not, unlike some hominid fossils, have a friendly nickname. He -- the fossil is believed to be that of an adult male Australopithecus africanus -- was around 25 years old when he apparently fell into a sinkhole in the rolling grasslands north of what is now Johannesburg and died. His remains were covered in sediment, turned to stone over thousands of years and lay buried until scientists discovered them in 1989.
For an object lesson -- literally -- in the origins of the human family, nothing compares with the Cradle of Humankind, as the area has been dubbed. The oldest hominid fossils in the world have been found in East Africa -- particularly Tanzania, Kenya, Ethiopia and Chad -- but the southern end of the continent also has a strong claim to being where our genus, Homo, first emerged: something of an evolutionary Garden of Eden.
Most visitors to South Africa in the next two months will be going for soccer's World Cup. But perhaps in their downtime they'd want to take two very different but equally fascinating side trips within two hours of Johannesburg: to the Cradle of Humankind and to the diamond mine in the town of Cullinan.
The Maropeng exhibition center in the Cradle tries to ensure that there is always at least one actual hominid fossil, not a replica, on display in its specialized glass cases; a few miles away, the Sterkfontein Cave, where Stw 505 was found, has yielded hundreds of specimens from no fewer than four different hominid species. Just over a hill from the cave is the site where two examples of a new species, Australopithecus sediba -- announced last month to global acclaim -- were found; some paleoanthropologists believe A. sediba represents a transitional stage between australopithecines and Homo.
Collen Tshegang, a guide at Sterkfontein, makes a point of asking visitors whether they have been there before. "What took you so long?" he asks when no one raises their hand. "Welcome home."
Sterkfontein's former residents include two of the most famous hominid fossils in the paleontological canon. "Mrs. Ples," a 2.15-million-year-old Australopithecus africanus, was at first thought to be female but now is considered to be an adolescent male, so perhaps would be more accurately called "Master Ples." In a side chamber behind a locked double door just beyond the entrance to the cave, more than 12 years of painstaking excavation work on "Little Foot," possibly the most complete australopithecine skeleton ever found, is expected to be completed before December.
"Mrs. Ples" is now kept in the vaults of the University of the Witwatersrand, under the care of Francis Thackeray, the director of the university's Institute for Human Evolution, who joined me at Sterkfontein for a tour. Thackeray shies away from using the term "missing link" or even "ancestor" in referring to the hominids. He prefers "distant human relatives" instead. That term "is a good way of getting around the problem of which species is directly ancestral to humans," he said. "There are many family trees."
Visiting the site was the fulfillment of a long-held dream for Dan Farslow, 64, a consultant from Columbus, Ohio, who used to teach anthropology at Ohio State and the University of Toronto and was almost beside himself with excitement. "It's awesome to actually be here on the ground," he said. "I haven't lost my childhood madness for this sort of thing. It's ancestral. The world is full of such wonderful humans, and protohumans are very much human to me. I have always thought that they are very much us, and we are very much them."
"We are all connected," added his wife, Nancy Kirwin, who, once in the cave, said she was "definitely" going to cry.
Much of the grotto was excavated in the late 19th and early 20th centuries by limestone miners who blasted out the rocks with explosives to extract lime for use in the gold-mining industry. (Johannesburg is a city founded on the riches of the Witwatersrand Reef, the biggest gold seam anywhere on Earth.) The damage the miners wreaked has left only a few sections retaining the ethereal formations that usually draw visitors to underground caves, but without it the fossils might never have been uncovered.