The much earlier candidate, chronologically speaking, of the human hominid ancestor is Australopithecus.24 It was first discovered by Raymond Dart in 1924 and named Australopithecus africanus. He highlighted many monkey-like features of the skull but believed that some characteristics of the skull, and especially the teeth, were similar to humans. The name “Australopithecus” means “southern ape,” but after Dart more thoroughly examined the teeth, he decided that A. africanus was a hominid. This claim created controversy – many who worked on the subject at that time argued that A. africanus was an ape with interesting but irrelevant parallel traits to humans. Later discoveries of Australopithecus were made by Robert Broom, John T. Robinson, and Dart.
The discovery by Louis Leakey and his wife, whom they named Zinjanthropus bosei, or “East African man,” in the Olduvai Gorge in Tanzania, attracted great attention. As was anticipated, they did not find anything essentially different from what Dart had discovered many years earlier. Their research, however, was sponsored by the National Geographic Society, and the combination of extremely extravagant claims by Leakey himself about his discovery and publicity through the pages of National Geographic magazine succeeded in promoting the idea that Leakey had made a unique and significant discovery at Olduvai. However, even Leakey later noted that his Zinjanthropus bosei was a subspecies of Australopithecus previously discovered in South Africa. Zinjanthropus bosei is now classified as Australopithecus bosei, and some even believe it is a subspecies of Australopithecus robustus.
Australopithecines were generally classified into two species. One is much more refined with smaller jaws and teeth, and is labeled as Australopithecus africanus. The other has much more massive teeth and jaws and possesses sagittal and supramastoid crests (bone ridges) found in gorillas and orangutans, and is called Australopithecus robustus.
Each of these animals has a small brain, with an average cranial capacity of 500 cm³ or less, which is on the level of a gorilla or one-third of a human’s. These animals, therefore, undoubtedly have a monkey’s brain, regardless of what else may be said about them. Both species had monkey-like teeth and jaws, which is clearly seen in the case of A. robustus.
Their dental characteristics, above all, are, according to many, what makes them unique and what led paleoanthropologists to classify them as hominids. The front teeth are relatively small, and the dental arch or jaw curvature is more parabolic and less “U”-shaped than is typical for modern monkeys. It is also claimed that the morphology or shape of the teeth in many characteristics is more human-like than monkey-like. The molars (premolars and wisdom teeth), however, are very massive, even in the more refined or africanus form. A. africanus, even weighing only 30 or 35 kg, or the size of the smallest chimpanzee, had molars larger than those of chimpanzees and orangutans, and as large as those of gorillas, some of which weighed 200 kg. As a result, the jaws are very large, especially in A. robustus.
Some parts of the pelvic, limb, and foot bones of these animals were later studied, and based on studies of these fragments, evolutionists agreed that australopithecines walked upright. This was especially solidified after support from authorities such as Broom27 and Le Gros Clark28.
Estimation of Australopithecus by Lord Zuckerman and Charles Oxnard
Recently, however, this view was opposed by Solly Lord Zuckerman,29-30 a famous British anatomist, and Dr. Charles Oxnard,31-34 director of Graduate Studies and professor of anatomy at the University of Southern California Medical School.
For over fifteen years, a research team led by Lord Zuckerman studied the anatomical structures of humans, monkeys, and fossil australopithecines. Practically all available and important fossil fragments of Australopithecus, along with anatomical samples of hundreds of monkeys and humans, were compared.
Evaluating the claim by Le Gros Clark and others that Australopithecus should be classified as a species of Hominidae (the human family) rather than as a species of anthropoid apes, Lord Zuckerman stated:
“But I am completely unconvinced. Almost always, when I tried to check anatomical claims on which the status of Australopithecus was based, I ended in failure.”35
Lord Zuckerman’s conclusion was that Australopithecus was an ape, with no connection to the origin of humans.
Oxnard’s research led him to state:
“Almost all studies underline the similarity between australopithecines and modern humans, suggesting that these creatures were bipedal tool users and that one species (Australopithecus africanus – ‘Homo habilis,’ ‘Homo africanus’) almost directly led to humans, while a series of various statistical studies of various postcranial fragments suggest other conclusions.”36
From his results, Oxnard concluded that Australopithecus did not walk upright in a human-like manner. He says:
“Various studies of several anatomical regions, shoulders, pelvis, ankle, foot, elbow, and hand of australopithecines, are now available. This suggests that the common view that these fossils are similar to modern humans, or that when they separated from similarity with humans, they began to resemble large African apes, may be incorrect. Many of the fossil fragments are in fact completely different from both humans and their closest genetic relatives, chimpanzees and gorillas.
In terms of similarity with living forms, they lean toward similarities with orangutans.”37
Finally, completely independent information from fossil findings in recent years seems to absolutely point to the fact that australopithecines, aged between half a million to two million years and originating from Olduvai and Sterkfontein, were not on the path to developing into humans.”38
Oxnard’s conclusion, therefore, is that Australopithecus was not the ancestor of any modern form, human or ape, but was uniquely different. If Oxnard and Lord Zuckerman are correct, then Australopithecus was neither the ancestor of humans nor an intermediary between monkeys and humans.
The Jaw Bone of Australopithecus robustus
Of great importance was the discovery and study of the anvil sample of an Australopithecus robustus specimen (SK 848), made by Rak and Clark.39 According to Rak and Clark’s claim, this jaw bone was not only essentially different from the anvil of modern humans, but the difference was greater than the difference between African apes and modern humans. They believe this is of great interest in regard to advancements in phylogenetic and taxonomic studies of the jaw bone.
- Literature 24. D. R. Pilbeam, The Evolution of Man, Funk and Wagnalls, New York, (1970).
- Pilbeam, Ref. 24, p. 99.
- Pilbeam, Ref. 24, p. 83.
- R. Broom and G. W. H. Schepers, Transv. Mus. Mem. 2:1 (1946).
- W. E. Le Gros Clark, J. Anatomy (London) 81:300 (1947).
- S. Zuckerman J. Roy. Col. Surg. Edinburgh 11:87 (1966).
- S. Zuckerman, Beyond the Ivory Tower, Taplinger Pub. Co., New York, 1970, p. 75-94.
- C. E. Oxnard, Nature 258:389-395 (1975).
- C. E. Oxnard, Homo 30:243 (1976).
- C. E. Oxnard and F. P. Lisowsky, Am. J. Phys. Anthropol. 52:116 (1980).
- See B. Wood, Nature 262:331 (1976).
- Zuckerman, Ref. 30, p. 77.
- Oxnard, Ref. 31, p. 389.
- C. E. Oxnard, University of Chicago Magazine, winter 1974, p. 11-12.
- C. E. Oxnard, Ref. 32, p. 242.
- Y. Rak and R. J. Clarke, Nature 279:62 (1979).