Aus­tralo­p­ithe­cus, which means south­ern ape”, was actu­al­ly an upright-walk­ing hominid with human-like teeth and hands. Its main ape-like fea­tures were a small brain, flat­tened nose region and for­ward-pro­ject­ing jaws. Dif­fer­ent species of this genus pop­u­lat­ed the east­ern and south­ern parts of Africa between 4-mil­lion and 2-mil­lion years ago.

One genus, many species

There were many dif­fer­ent species of the Aus­tralo­p­ithe­cus genus. More fos­sils of Aus­tralo­p­ithe­cus africanus, which lived between 3-mil­lion and 2-mil­lion years ago, have been found at the Cra­dle of Humankind than any oth­er hominid species.

Australopithecus Image2

An artist’s impres­sion of Aus­tralo­p­ithe­cus

The first adult spec­i­men of an Aus­tralopethi­cus was dis­cov­ered in 1936 at Sterk­fontein by palaeon­tol­o­gist and direc­tor of the Trans­vaal Muse­um, Dr Robert Broom.

Sts 5 (Mrs Ples), which he dis­cov­ered in 1947, and many oth­er spec­i­mens found in Sterk­fontein Mem­ber 4, also belong to this species. These include the less­er known cra­nial spec­i­mens Sts 17 and Sts 52, and a par­tial skele­ton, Sts 14, found in 1947, which had a com­plete pelvis that affirmed that Aus­tralo­p­ithe­cus was bipedal, or walked upright.

But there are oth­er aus­tralo­p­ithecines dis­cov­ered at the Sterk­fontein Caves and at Maka­pans Val­ley, about 300 km (480 mi) from Sterk­fontein, near Mokopane in Limpopo Province, which may not be Aus­tralo­p­ithe­cus africanus. These include sev­er­al spec­i­mens, such as Stw 252, and Sts 71, dis­cov­ered by Broom and his col­league, John Robin­son, in 1947.

Palaeoan­thro­pol­o­gist Pro­fes­sor Ron Clarke has argued that Stw 252 appears very dif­fer­ent from Aus­tralo­p­ithe­cus africanus in that it has much larg­er teeth, a flat­ter upper face, a thin­ner brow region and a dif­fer­ent­ly shaped brain­case. He observed the same fea­tures in Sts 71, and sug­gest­ed these, plus some oth­er large-toothed hominids from Sterk­fontein and the Maka­pans Val­ley, rep­re­sent anoth­er Aus­tralo­p­ithe­cus which lived at the same time as Aus­tralo­p­ithe­cus africanus. This sec­ond species is yet to be named.

Lit­tle Foot”, which is still being exca­vat­ed from Sterk­fontein Mem­ber 2, is one of the old­est aus­tralo­p­ithecines ever found, dat­ing to between 4.1-million and 3.3-million years old, accord­ing to palaeo­mag­net­ic evi­dence and cos­mo­genic iso­tope dat­ing. The species to which the skele­ton belongs will only be deter­mined when it has been com­plete­ly extract­ed from the rock in which it lies embed­ded. Oth­er hominid remains dat­ing to a sim­i­lar time have also been recov­ered from the Jacov­ec Cav­ern at Sterkfontein.

Aus­tralo­p­ithe­cus has also been found at Maka­pans Val­ley in South Africa’s Limpopo Province, which is part of the Cra­dle of Humankind World Her­itage Site. Remains of oth­er ear­ly species of Aus­tralo­p­ithe­cus have been found in East Africa.

Aus­tralo­p­ithe­cus afaren­sis, which lived between 3.6-million and 3-mil­lion years ago, has been found at Lae­toli in Tan­za­nia, where foot­print trails of Aus­tralo­p­ithe­cus were uncov­ered in 1978, and at Hadar in Ethiopia, includ­ing the famous Lucy skele­ton dis­cov­ered in 1973. Aus­tralo­p­ithe­cus ana­men­sis, found in Kenya, is the most ape-like and old­est of the aus­tralo­p­ithecines, dat­ing to between 4.2-million and 3.9-million years ago.

The Taung Child

One Sat­ur­day in 1924, a young sci­en­tist, Dr Ray­mond Dart, an

Aus­tralian by birth who stud­ied in Eng­land and had come out to South Africa as head of the Uni­ver­si­ty of the Witwatersrand’s Depart­ment of Anato­my, received two large wood­en box­es con­tain­ing fos­sils at the door of his house, just as he was prepar­ing to attend a wedding.

Taung Child

Fos­sil of the Taung child

The fos­sils had been sent by his geol­o­gist col­league, Pro­fes­sor RB Young, from the Bux­ton Lime­works in the small town of Taung, about 150 km (95 mi) from Kim­ber­ley, in what is now the North West Province of South Africa and which now forms a part of the Cra­dle of Humankind World Her­itage Site.

When he removed the lid from the sec­ond box, Dart was amazed to see the fos­silised cast of a tiny brain on top of the pile. It belonged to the Taung Child, and was to become one of the most remark­able sci­en­tif­ic dis­cov­er­ies ever made.

Dart wrote of the moment in his book, Adven­tures with the Miss­ing Link:
On the very top of the rock heap was what was undoubt­ed­ly an endocra­nial cast or mould of the inte­ri­or of the skull. Had it been only the fos­silised brain cast of any species of ape it would have ranked as a great dis­cov­ery, for such a thing had nev­er before been report­ed. But I knew at a glance that what lay in my hands was no ordi­nary anthro­poidal brain. Here in lime-con­sol­i­dat­ed sand was the repli­ca of a brain three times as large as that of a baboon and con­sid­er­ably big­ger than that of an adult chimpanzee.”

For three months, Dart scratched the skull from its rocky matrix using his wife’s sharp­ened knit­ting nee­dles. Two days before Christ­mas, he final­ly freed the child from the rock.

He lat­er wrote: I doubt if there was any par­ent proud­er of his off­spring than I was of my Taung baby that Christ­mas of 1924.”

The Taung Skull – small enough to fit in the palm of a hand – was that of a three or four-year-old child, and much small­er than a mod­ern human of the same age. It had small canine teeth, and the posi­tion of the fora­men mag­num, where the spine joins the base of the skull, showed it walked upright – two dis­tinct dif­fer­ences from true apes.

Ear­ly in 1925, Dart described the find in the jour­nal Nature, and so iden­ti­fied and named not only a new genus and species, but also an as yet unknown human ances­tor. Before this, the only human ances­tors known to sci­ence had been the Nean­derthals of Europe and the fos­sils of Homo erec­tus found in Java, Indone­sia. Dart called his find Aus­tralo­p­ithe­cus africanus.

The reac­tion to the dis­cov­ery was far from con­grat­u­la­to­ry or excit­ed. Dart was vil­i­fied for dar­ing to sug­gest that humankind could have orig­i­nat­ed in Africa. Most sci­en­tists at the time thought human­i­ty had been born in Asia or Europe, par­tic­u­lar­ly after the dis­cov­ery of the Pilt­down Man” in Eng­land in 1912, which was lat­er exposed as a hoax. Not many peo­ple believed Dart until the 1940s and 1950s, when hominid fos­sils from the Cra­dle of Humankind in South Africa start­ed to swing the bal­ance of prob­a­bil­i­ty that humankind had, in fact, orig­i­nat­ed in Africa.

Dart’s stu­dent and suc­ces­sor, Pro­fes­sor Phillip Tobias, remarked of Dart’s find:
With bril­liant insight and no small courage, he made a giant intel­lec­tu­al leap and con­clud­ed that it was nei­ther ape nor human but a miss­ing link’ in the old-time Chain of Being. He named it Aus­tralo­p­ithe­cus africanus (‘south­ern ape of Africa’). It was an ape which had under­gone some cru­cial evo­lu­tion­ary changes in a human direc­tion. Knock­ing on the door of human­i­ty, it had not crossed the threshold.”

Mrs Ples

Mrs Ples 1

An artist’s impres­sion of Mrs Ples

Mrs Ples was born over 2-mil­lion years ago, and lived and died in the Cra­dle of Humankind. In 1947, palaeon­tol­o­gists Dr Robert Broom and John Robin­son dis­cov­ered her skull encased in brec­cia in the Sterk­fontein Caves. Their find helped to high­light the view that humankind orig­i­nat­ed in Africa – some­thing which most sci­en­tists were scep­ti­cal of at the time.

The Star news­pa­per of Johan­nes­burg gave Mrs Ples her name, after Broom stat­ed the skull was a female of a species called Ple­sianthro­pus trans­vaalen­sis near-human from the Trans­vaal”, although she was lat­er iden­ti­fied as belong­ing to the same species as the Taung Child, Aus­tralo­p­ithe­cus africanus.

Mrs Ples remains one of the most com­plete skulls of this species ever uncov­ered. Her fame has been min­gled with con­tro­ver­sy – Dr Fran­cis Thack­er­ay of the Trans­vaal Muse­um has argued that Mrs Ples is, in fact, the fos­sil of a young male. He has also main­tained that a few skele­tal parts found at rough­ly the same time close to the skull may also have belonged to Mrs Ples, though not all palaeoan­thro­pol­o­gists agree with this view.

The hypoth­e­sis that Mrs Ples was a male is based in part on ridges on the face (ante­ri­or pil­lars) of the kind that are usu­al­ly found in male spec­i­mens of Aus­tralo­p­ithe­cus africanus. If she were in fact male, Mrs Ples would have been rel­a­tive­ly small. The fact that Mrs Ples was an ado­les­cent is indi­cat­ed by the open roots of wis­dom teeth that have been recog­nised from X-ray analy­sis (CT scans) of the fossil.

Mrs Ples was clear­ly on the road to human­i­ty. She could walk upright, but had a small­er brain, sim­i­lar in size to that of a mod­ern chim­panzee. Some researchers believe that humans and chim­panzees had a com­mon ances­tor, which lived in Africa about 8-mil­lion years ago, while oth­ers con­sid­er there is a clos­er rela­tion­ship with orang­utans. But at about 2-mil­lion years old, Mrs Ples is more close­ly relat­ed to humans than to mod­ern apes.

Recent research sug­gests that Mrs Ples is one of the youngest known fos­sils rep­re­sent­ing Aus­tralo­p­ithe­cus africanus. It was found in deposits that have been dat­ed to about 2.1-million years old. Not long after that, Aus­tralo­p­ithe­cus africanus was to become extinct.

How the first adult aus­tralo­p­ithecine was found

Dr Robert Broom, a renowned palaeon­tol­o­gist and head of the Trans­vaal Muse­um, sup­port­ed Prof Ray­mond Dart’s hypoth­e­sis that the Taung Child was a hominid, even when it was unpop­u­lar to do so. He dreamed of find­ing an adult aus­tralo­p­ithecine, and went look­ing in dolomite caves west of Pre­to­ria, where he dis­cov­ered instead the fos­sil of a giant baboon, which received con­sid­er­able press coverage.

Robert Broom

Robert Broom

After read­ing about this in a news­pa­per, two of Dart’s stu­dents, Hard­ing le Riche and GW Schep­ers, who had found fos­sil mon­key skulls at Sterk­fontein, took Broom to the caves.

Here, Broom met George Bar­low, the site man­ag­er, who, as luck would have it, had also worked at Taung, where the first Aus­tralo­p­ithe­cus, the Taung Child, had been found. Broom asked Bar­low to keep an eye out for any­thing sim­i­lar to the Taung Skull, and a few days lat­er, Bar­low hand­ed him a rare find: the world’s first adult spec­i­men of Aus­tralo­p­ithe­cus, lat­er cat­a­logued as TM1511.

In his 1950 book, Find­ing the Miss­ing Link, palaeon­tol­o­gist Dr Robert Broom described the moment when he saw the first adult aus­tralo­p­ithecine that had ever been found:

On the Mon­day fol­low­ing, August 17th, 1936, I was again at Sterk­fontein and when I saw Bar­low, he hand­ed me a beau­ti­ful brain-cast and said Is this what you’re after?’… It was clear­ly the ante­ri­or two-thirds of a brain-cast of an anthro­poid ape or ape-man, and in per­fect con­di­tion. It had been blast­ed out that morn­ing. I hunt­ed for some hours for fur­ther remains, but with­out suc­cess. But I found the nat­ur­al cast of the top of the skull in the side of the quar­ry and had this care­ful­ly cut out… Next day I was back and dis­cov­ered the base of the skull on which the brain-cast had rest­ed, with all the blocks that had been attached to it… To have start­ed to look for an adult skull of Aus­tralo­p­ithe­cus and to have found an adult of at least an allied form in about three months was a record… And to have gone to Sterk­fontein and found what we want­ed with­in nine days was even better.”

Read about the excit­ing find of the Lit­tle Foot skele­ton, an Aus­tralo­p­ithe­cus, deep inside the Sterk­fontein Caves.