The case of who killed the single most important human ancestor has finally been laid to rest after more than 80 years of debate and scientific investigation. The announcement that the Taung child was killed by an eagle was made on Thursday by Professor Lee Berger at an international conference held at the University of the Witwatersrand (Wits) in Johannesburg.
Since the Taung child’s discovery in 1924, leopards or sabre-toothed cats have always been blamed for the child’s death. The Taung child is a specimen of the human ancestor species Australopithecus africanus and the first early human ancestor fossil to be discovered in Africa, according to a statement released by Wits on Thursday.
Ten years ago, Berger and Dr Ron Clarke of Wits challenged the world’s scientific community with the idea that the little Taung child had probably been killed by a large bird of prey.
Berger and Clarke shocked the scientific community by claiming that the skulls and bones of monkey and animal fossils from the Taung site in north-western South Africa showed distinctive evidence of eagle-caused damage. They proposed that the three-and-a-half-year old Taung child, who died nearly two million years ago, had also been killed by an eagle, probably similar to the present-day crowned eagle of Africa.
”While some colleagues accepted that the damage to the Taung fossil monkeys was probably made by a bird of prey, the majority felt that apemen, even baby apemen like the Taung child, were way too large, sophisticated and organised to be taken by an eagle,” says Berger, who is now a reader in palaeoanthropology at Wits.
”There were several debates in international journals about whether an eagle could lift a child as heavy as the Taung baby,” he says.
A decade after the first hypothesis was formed by Berger and Clarke, more than two dozen scientists have published more than 20 academic papers weighing up the pros and cons of the Taung bird-of-prey hypothesis.
”The one big problem was the lack of multiple areas of damage on the Taung child itself that could be linked to a bird of prey,” says Berger. ”We had one little flap of bone on the top of the skull that looked like some of the damage we see made by eagles, and nothing else. Most of my colleagues felt we had reached the end of the road in solving this problem. It was the ultimate two-million-year-old cold case!”
That is, until Drs Scott McGraw, Catherine Cooke and Suzanne Schultz, of the department of anthropology at Ohio State University in the United States, submitted their paper on Primate Remains from African Crowned Eagle (Stephanoaetus coronatus) Nests in Ivory Coast’s Tai Forest: Implications for South African Cave Taphonomy in the prestigious American Journal of Physical Anthropology.
Berger was asked to review this paper — the most comprehensive study of eagle damage on bone conducted to date.
”The paper supported Dr Clarke’s and my original hypothesis that the Taung animals had been collected by a bird of prey, but frustratingly McGraw and his colleagues again noted that we would never know for sure whether the Taung child itself was collected by a raptor because it lacked critical ‘marker’ damage,” says Berger.
But the McGraw paper went further than any previous research. The Ohio-based scientists had found several key features of damage on bone that separated eagle damage from that made by other predators, such as big cats. These key markers included flaps of depressed bone on top of the skull and ”keyhole-shaped” cuts in the side of skulls made by birds’ beaks, all features noted in Berger and Clarke’s 1995 paper.
”They also found one suite of characters I had never before seen described, characters that were unique to eagle-damaged skulls and were sure clues to raptor involvement,” Berger explains.
”These critical clues were puncture marks and ragged incisions in the base of the eye sockets of primates, made when the eagles ripped the eyes out of the dead monkeys with their sharp talons and beaks. It was a marker that others hadn’t noted before, that linked eagles definitively to the kill.”
Berger was then driven to re-examine the Taung child, probably the most photographed human ancestor with possibly more casts of it scattered around the world than from any other single fossil.
Berger recounts: ”I almost dropped down when I looked into the eyes of the skull as I saw the marks, as described in the McGraw paper — they were perfect examples of eagle damage! I couldn’t believe my eyes as thousands of scientists, including myself, had overlooked this critical damage.
”I even went to look at an original 1925 cast of the child to make sure the damage had been there originally, and it had. I felt a little bit like an idiot for not seeing those marks 10 years ago, but at least we had them now.
”People don’t know how rare it is for a scientific theory to be actually proven beyond a reasonable doubt. It’s incredibly gratifying after 10 years of work. These types of discoveries give us real insight into the past lives of these human ancestors, the world they lived in and the things they feared. And in that is the clue to understanding why we humans today view the world the way we do.
”These are the stresses that formed the human mind and made us one of the most successful animals on the face of the planet.”
The announcement about the Taung child was made on Thursday at an international conference held at Wits. The conference celebrates the 80th anniversary of the Taung child’s discovery and the 80th birthday of Professor Phillip Tobias.
Both journal papers detailing the discoveries will appear shortly in the American Journal of Physical Anthropology. More information: Tel: 011 717 1019 or [email protected]