Dating these cultures in terms of our years is another matter. The first step is fairly simple. If the tools are found with the fossils of a warmth-loving animal like the hippopotamus, they belong to an interglacial period; if they are found with the fossils of an animal like the hairy mammoth, which could survive a harsh climate, they belong to a glacial time. The species of animal may determine which glacial or which interglacial. If the tools are found in the gravel of a certain river terrace, then they belong to the geological period when the material of the terrace was being laid down. The terraces often contain fossils, and this may cross-date the terrace materials with cave deposits. But scientists are often faced with the problem of picking the right glacial or interglacial period on scanty evidence, and the still more difficult problem of setting the period in the terms of our years. There is room here for much disagreement. Glaciologists do not agree as to the age or the length of the various glacials and interglacials (see illustration, [page 55]). Some prehistorians accept and use the dates of one glacialist; some choose another’s. They do not all concur as to which culture came in which glacial period.
True Tools—Deceptive Skulls
Men who practiced Abbevillian culture had some flaked tools—which they may have used for scraping—but their best-recognized output was a crude hand ax. It was not too well formed. Undoubtedly they also used wood and bone, but we have no sure evidence of this. Some assign Abbevillian culture to the first interglacial period, about 500,000 years ago. Some move it up 200,000 years, into the second interglacial. Some even place it in the third. Perhaps it lasted through all three. At any rate, the men who made it liked a fairly warm climate. As neither they nor their Acheulean successors made fire or controlled it effectively, the early Europeans probably retreated to Africa during the glaciations.
Ancient implements of bone and wood. Left, part of the thigh bone of a mammoth, found at Piltdown, England, in the same deposit as the now infamous skull; it, too, is a forgery. Right, part of a wooden spear, its point hardened by fire, found at Clacton-on-Sea, England, and probably made by Acheulean or Mousterian man. (Left, after Dawson and Woodward, 1917; right, after Crawford, 1921.)
The Acheulean hand ax was thinner and better, and it is found with various kinds of scrapers and cleavers. Probably it was this culture that left us part of a very crude wooden spear at Clacton-on-Sea, in England, though some date it a little later. The earliest association of human remains with tools in Europe is that of the Swanscombe skull and Acheulean tools in Pleistocene gravels of the Thames in Kent.
We are not too sure about the physical appearance of the men of Abbevillian and Acheulean times. For the Abbevillian there is possibly a fragment of jaw, a most interesting one, to be sure, but not actually found with any kind of artifact. For Acheulean times there are no dependable skeletons to help us, and not even complete skulls. In fact, there are not as many candidates for the position as we thought we had a decade or so ago.
Galley Hill man turned out to be a case of mistaken identity. He has a thick skull and a few other primitive traits—a fossil type of modern man, perhaps, but not nearly as old as we once thought. His bones lacked a fluorine mineral content typical of other fossils that belonged in the interglacial deposits where the Galley Hill skull reposed, eight feet below the surface.
The same fluorine test—which fortunately applies to such fossilated things as bone, antler, and ivory—exposed an even more notorious impostor, expelling him from the select corps of early men. This was Piltdown man, alias Homo eoanthropus dawsoni, alias Eoanthropus, alias Dawson’s Dawn Man. It was demonstrated to be a fake and a forgery that led its discoverer to try to match a reasonably human skull to the jaw of an ape. The jaw and its teeth had been modified by the faker—not Dawson—to make it appear less apelike. Both jaw and skull had been artfully treated with chemicals to appear as antiquated as the unusual assortment of fossils with which they were salted into early interglacial deposits. Many of the fossils, while authentic in their own right, also were chemically stained and planted. And tools were added to complete the assemblage. The latter included a bone pick thoughtfully carved from the femur of an elephant, but it was carved with a modern steel knife, as careful scrutiny under a powerful lens disclosed, and not with the stone flakes of prehistoric man. (See illustration, [page 74].)
The British scientists Kenneth Oakley, J. S. Wiener, and Sir Wilfrid Le Gros Clark exposed the forgery in a most conclusive manner.[9] In laying the ghost of Piltdown, these authorities resolved four decades of controversy as to his place in human evolution. Although Piltdown’s contribution to human evolution now is known to have been nil, his contribution to physical anthropology has been considerable. As the academic dust settled on this issue, the anthropologists returned to their laboratories with greater confidence in their science and with somewhat sharper tools in their research kits. It is unlikely that any new hoax will ever acquire the same importance as Piltdown.