To understand the story of Australopithecus africanus, we have to start with another discovery in England …

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3d print of Taung baby skull

In 1912, a British lawyer named Charles Dawson, who dabbled in amateur archaeology and was a collector for the Natural History Museum in London, brought some broken bone fragments that he had found four years earlier to Arthur Smith Woodward at the Museum. The bones were pieces of skull that looked very humanlike, but appeared to be very old. Woodward excitedly asked Dawson where he had found the bones, and was pointed to a gravel pit at Piltdown Commons, in Sussex.

Woodward and Dawson went to the gravel pit and dug further, and uncovered two jaw fragments with teeth that looked very much like an ape but had humanlike molars, and also found some stone tools and the bones of Ice Age mammals. Here was the evidence that British paleontologists had always expected to find–a big-brained human ancestor with an apelike jaw–the missing link. And, in a happy patriotic circumstance that was not lost on these British gentry, it was found in England. Woodward quickly submitted his findings and christened the fossil Eoanthropus dawsoni (“Dawson’s Dawn Man”).

But there were skeptics. Some paleontologists thought it was just an old human skull, with no clear apelike characteristics. And right on cue, in 1913, a new discovery made in the Piltdown pit, this time by amateur fossil hunter Father Pierre Theilhard de Chardin, settled that question–a perfectly preserved canine tooth, long and apelike.

Other paleontologists noted that there was no reason to conclude that the jawbone and the skull actually belonged together–they may have been entirely unrelated. And in 1915, again right on cue, Dawson found some fragments from a second skull and jaw, a few miles away, though he didn’t reveal the exact location of the find. This was enough to convince some doubters of Piltdown’s authenticity: a chance association between an apelike jaw and a humanlike skull might happen once, but not twice.

More pieces followed: bone fragments, more stone tools, and a piece of elephant bone identified as a “ritual object” that looked suspiciously like an English cricket bat. (The “cricket bat” was not even found in the actual gravel pit–it was found under a nearby hedgerow.)

A handful of scientists (mostly American) argued that the Piltdown fossil didn’t make any sense, and concluded that the skull and jaw must be from two separate species and did not actually belong together. The Europeans, on the other hand, embraced Piltdown enthusiastically, because it told them what they already wanted to hear–humans were distinguished very early by a large brain, and these big-brained early humans were (white) Europeans.

In the meantime, new fossil discoveries were being made elsewhere. In 1924, Raymond Dart, an Australian doctor working in London, went to Johannesburg in South Africa and became the head of the anatomy department at the University of Witwatersrand. When he asked his students to bring in interesting bones for study, Josephine Salmons (his only female student) brought him a fossilized baboon skull which had been dug up at the Northern Lime Company’s limestone mine at Taung. Dart contacted the mine and asked that any other fossils that might be found in the future be sent to him. That summer, Dart received two large boxes from Taung, and in one he found the fossil skull of a young primate, and the fossil endocast of the brain cavity. Having no lab equipment available to him, Dart set about removing the hard breccia rock from the fossils using his wife’s steel knitting needles.

He revealed the skull of a very young primate, still with its milk teeth, that had humanlike teeth and not the large canines of an ape, a flat humanlike face rather than the projecting muzzle of an ape, and which, judging from the location of the hole at the bottom where the spine entered, belonged to an upright-walking bipedal creature. As an anatomist, Dart also recognized immediately that the brain endocast showed an unmistakably human pattern, despite its relatively small size. Dart, believing the “Taung Child” to be an evolutionary intermediate between apes and humans, nevertheless gave it the conservative scientific name Australopithecus africanus, “the southern ape from Africa”.

Dart’s find caused barely a ripple in Europe. Scientists in England and France rejected Dart’s assertion that this was a human ancestor. They pointed out that young apes always look more like humans than adult apes do, and concluded that Dart (who, they smugly pointed out, was not a trained paleo-anthropologist but a mere medical doctor and anatomist) had simply mistaken a young ape for a human. Other reasons for rejecting Australopithecus went unsaid but were nevertheless perfectly clear–Dart was an Australian and was living and working in a cultural and intellectual backwater in Africa, and his find did not support the preferred “big-brained Europeans” hypothesis.

Only one scientist openly supported Dart’s conclusions. Robert Broom, of the Transvaal University in Pretoria, was best-known as an expert on the Permian mammal-like reptile fossils, but Dart’s find interested him, and he became the most ardent defender of Australopithecus. At first, no one paid him much attention; Broom was already known as a gadfly–a spiritualist with an interest in the paranormal, he asserted that the process of evolution was directed by “spiritual forces”, and once declared that “spirits” told him where to look for fossils.

Whether guided by spirits or not, Broom now had a remarkable string of luck. In 1935, he found some small fragments of humanlike bones at the Sterkfontein cave, about 30 miles northwest of Johannesburg. Further digging revealed some complete bones, which Broom concluded were the adult version of Dart’s Australopithecus. In 1937, at a nearby cave called Kromdraai, Broom found bones that were similar to Australopithecus but thicker and more robust, which he named Paranthropus.

After being delayed by World War II, Broom restarted his excavations, and in 1947, at Sterkfontein, found a nearly intact skull that he named Plesianthropus transvaalensis (“near-man from Transvaal”), which was given the nickname “Mrs Ples”. Today, Mrs Ples is grouped with A africanus. In 1948, Broom found more hominid fossils at the nearby Swartkrans cave.

3d print of Australopithecus africanus skull

Like Dart’s discovery, Broom’s findings were mostly rejected by European paleo-anthropologists and regarded as a mere side line, some sort of ape.

But then in 1953, came an unexpected bombshell: a new dating technique using measurements of flourine levels showed that the Piltdown jaw and the skull were both recent and not ancient, and were not both the same age. They did not belong together. But even further, close examination revealed that both the skull and the jaw had been deliberately altered as an intentional fraud. The skull was that of a medieval human which had been chemically stained to make it look older. The jaw was an orangutan which had also been stained to match the skull, and the molars had been filed down to make them look humanlike. Finally, the stained loose teeth were from a chimpanzee, also filed down. “Piltdown Man” was a fake.

All of this at last convinced paleo-anthropologists that the earliest hominids did indeed appear in Africa. As of today,all of the earliest hominids that we know about lived in Africa (including the earliest members of our own species, Homo sapiens.) At our deepest roots, we are, all of us, Africans.

Since Broom’s work, there have been many additional finds of A africanus, and it is now one of the most well-known of the hominin species. Bones from at least 250 different individuals have been found, ranging in age from 3.2 to 2 million years ago. Oddly, all of them have been found in South Africa, and they have not (yet) been found in any other area. Most finds have come from the caves in the vicinity of Sterkfontein and Makaganspat, and this area is now protected as the “Cradle of Humankind” preserve.

A africanus was very clearly a biped. The feet, knees, pelvis, spine and foramen magnum all indicate that they walked on two legs, though they still retained some curved bones in the fingers, an upward-facing shoulder joint, and arms that were slightly longer than modern humans (though much shorter than the earlier australopithecines). They were apparently adapted to a life on the ground, and indeed the environmental markers found along with them indicated that by this time Africa was becoming drier and cooler, the former forested habitat was shrinking, and open grassland savannas were becoming dominant. Chemical analysis of the theeth indicates some fruit and leaves in the diet, but mostly C4-type grassland foods. Some small amount of this, it is postulated, may have come from the meat of herbivorous animals, which was, it is assumed, scavenged from predator kills. But there is, so far, no direct evidence for this.

Most paleo-anthropologists consider africanus to be in the direct human ancestral line, perhaps leading to Homo erectus, though it has also been argued that it was just a side shoot and that we are descended from some other australopithecine. It has also been asserted that africanus is ancestral to the Paranthropus line, while others have proposed that A garhi is a descendant of africanus. The picture remains unclear. But it is apparent that Australopithecus africanus was, in evolutionary terms, a very successful species.