Man-Apes or Ape-Men in Africa
While Sunday supplements and scientists alike were occupied with Dubois’s “missing link” and his Peking cousin, primate fossils of even greater consequence were being recovered in southern Africa by Professor Raymond Dart and the late Dr. Robert Broom. In 1925, Dart named them Australopithecines or “southern apes.”[14] Arousing little scientific curiosity at first, they were considered by some as a parallel, perhaps profitless, line of evolution. By 1950, such fossils were becoming impressively abundant. A bewildering array of names was assigned to them, without scientific justification. The first had been called Australopithecus africanus; later, another species, prometheus, was added. Others were labeled as distinct genera, taking note of their near-human features—Telanthropus, Plesianthropus, and Paranthropus (with two species, robustus and crassidens). In 1959, a new and important form was added, Zinjanthropus boisei. Zinj is the Arab name for East Africa. Expert opinion now inclines toward lumping these all together, possibly under our own genus, Homo, or at most, within a single genus, Australopithecus. Their status of “ape” is being reassessed: man-apes, some still maintain; ape-men, say others; a few believe they included the earliest true men.
The dividing line between ape and man is drawn partly upon physical grounds, but the greatest difference is a cultural one. Men possess and transmit culture, a process ordinarily regarded as involving language. Men make tools; apes do not. The smallest, crudest, and perhaps earliest of the Australopithecines have long been championed by Dart, who argues most persuasively that they were at least tool users, if not toolmakers. With their remains were those of other animals, a source of bones for picks and clubs, teeth for cutting and scraping, and so on. Perceiving crude, ready-made tools of bone, tooth, and horn, Dart coined the term “osteodontokeratic” for this pre-Stone Age assemblage.[15] This nomenclature was criticized by physical and cultural anthropologists alike. Whether this “culture” of the Australopithecines is real or—as many believe—imagined, there is no doubt about the equipment of Zinjanthropus. Associated with his bones are stone tools of the Oldowan culture, an Abbevillian-level, “Pre-Chelles-Acheul” industry of worked stone flakes. In the words of his discoverer, Dr. L. S. B. Leakey, here was the oldest maker of stone tools so far known. By 1960, the skull of Zinjanthropus had not been fully studied. In certain of its features, it favors Paranthropus, Australopithecus, or Homo. On first glance it seems as nearly human as Java man, which Leakey says it predates.[16]
There are two main difficulties in placing the Australopithecines on the line of human evolution. Although they might be said to resemble man more than the apes, they actually resemble neither, for their features are so specialized that it is difficult to conceive of them as ancestral to either. It is difficult, too, to place them in geologic time. Except for Zinjanthropus, who clearly belongs to the upper part of the Lower Pleistocene, most of the Australopithecines have been recovered from caves, fissures, or other places where there is no stratification. They are all much too old to be placed in time by some of our more precise dating techniques, such as the radiocarbon method. Non-primate bones found with them are typical of animals that in Europe ranged all the way from the Mid-Pliocene to the Mid-Pleistocene. South Africa is a cul-de-sac, relatively untouched by the Ice Age. The abundance and variety of animals surviving today in most of Africa south of the Sahara are reminiscent of the Pleistocene elsewhere. The index fossils of other lands are not much use when it comes to dating Australopithecus.
Once suspected of being Middle Pleistocene at the earliest, the Australopithecines’ apparent lack of culture, their crude development, and relatively small brain capacity indicated to some authorities that they were too little and too late to have been ancestral to man. But given a greater time span-back, say, to the Late Pliocene—they could be regarded seriously as mans ancestors. Somewhat cautiously, Sir Wilfrid E. Le Gros Clark seems to agree with Dart that, as a whole, the Australopithecines may well include the stock from which our own genus was derived.[17]
Back of the Australopithecines are yet other fossils of great interest, forms intermediate between man and apes in various ways. These all are utterly lacking in culture, in our sense of the word. One of the more interesting fossils is Oreopithecus bambolii, quantities of which have been recovered from a lignite mine at Baccinello, Italy.[18] These fossils seem to date from about the Early Pliocene. More than ape or monkey, their teeth are definitely manlike—hominid rather than merely hominoid—and the size of their brains is about that of the larger chimpanzees or the smaller Australopithecines. Future studies surely will indicate if, and perhaps how, Oreopithecus is related to the South African man-apes, and to man.