Reduction of anomaly by matching fact to expectation. We know, in retrospect, that Piltdown had a human cranium and an ape’s jaw. As such, it provides an ideal opportunity for testing what scientists do when faced with uncomfortable anomaly. G.E. Smith and others may have advocated an evolutionary head start for the brain, but no one dreamed of an independence so complete that brains might become fully human before jaws changed at all! Piltdown was distressingly too good to be true.
If Keith was right in his taunt to Weidenreich, then Piltdown’s champions should have modeled their theories to the uncomfortable fact of a human cranium and an ape’s jaw. Instead, they modeled the “facts”—another illustration that information always reaches us through the strong filters of culture, hope, and expectation. As a persistent theme in “pure” description of the Piltdown remains, we learn from all its major supporters that the skull, although remarkably modern, contains a suite of definitely simian characters! Smith Woodward, in fact, originally estimated the cranial capacity at a mere 1,070 cc (compared with a modern average of 1,400 to 1,500), although Keith later convinced him to raise the figure nearer to the low end of our modern spectrum. Grafton Elliot Smith, describing the brain cast in the original paper of 1913, found unmistakable signs of incipient expansion in areas that mark the higher mental faculties in modern brains. He concluded: “We must regard this as being the most primitive and most simian human brain so far recorded; one, moreover, such as might reasonably have been expected to be associated in one and the same individual with the mandible which so definitely indicates the zoological rank of its original possessor.” Just a year before Oakley’s revelation, Sir Arthur Keith wrote in his last major work (1948): “His forehead was like that of the orang. devoid of a supraorbital torus; in its modeling his frontal bone presented many points of resemblance to that of the orang of Borneo and Sumatra.” Modern Homo sapiens, I hasten to add, also lacks a supraorbital torus, or brow ridge.
Careful examination of the jaw also revealed a set of remarkably human features for such an apish jaw (beyond the forged wear of the teeth). Sir Arthur Keith repeatedly emphasized, for example, that the teeth were inserted into the jaw in a human, rather than a simian, fashion.
Prevention of discovery by practice. In former years, the British Museum did not occupy the vanguard in maintaining open and accessible collections—a happy trend of recent years, and one that has helped to lift the odor of mustiness (literally and figuratively) from major research museums. Like the stereotype of a librarian who protects books by guarding them from use, Piltdown’s keepers severely restricted access to the original bones. Researchers were often permitted to look but not touch; only the set of plaster casts could be handled. Everyone praised the casts for their accuracy of proportion and detail, but the detection of fraud required access to the originals—artificial staining and wear of teeth cannot be discovered in plaster. Louis Leakey writes in his autobiography:
As I write this book in 1972 and ask myself how it was that the forgery remained unmasked for so many years, I have turned my mind back to 1933, when I first went to see Dr. Bather, Smith Woodward’s successor…. I told him that I wished to make a careful examination of the Piltdown fossils, since I was preparing a textbook on early man. I was taken into the basement to be shown the specimens, which were lifted out of a safe and laid on a table. Next to each fossil was an excellent cast. I was not allowed to handle the originals in any way, but merely to look at them and satisfy myself that the casts were really good replicas. Then, abruptly, the originals were removed and locked up again, and I was left for the rest of the morning with only the casts to study.
It is my belief now that it was under these conditions that all visiting scientists were permitted to examine the Piltdown specimens, and that the situation changed only when they came under the care of my friend and contemporary Kenneth Oakley. He did not see the necessity of treating the fragments as if they were the crown jewels but, rather, considered them simply as important fossils—to be looked after carefully, but from which the maximum scientific evidence should be obtained.
Henry Fairfield Osborn, although not known as a generous man, paid almost obsequious homage to Smith Woodward in his treatise on the historical path of human progress, Man Rises to Parnassus (1927). He had been a skeptic before his visit to the British Museum in 1921. Then, on Sunday morning, July 24, “after attending a most memorable service in Westminster Abbey,” Osborn “repaired to the British Museum to see the fossil remains of the now thoroughly vindicated Dawn Man of Great Britain.” (He, at least, as head of the American Museum of Natural History, got to see the originals.) Osborn swiftly converted and proclaimed Piltdown “a discovery of transcendent importance to the prehistory of man.” He then added: “We have to be reminded over and over again that Nature is full of paradoxes and that the order of the universe is not the human order.” Yet Osborn had seen little but the human order on two levels—the comedy of fraud and the subtler, yet ineluctable, imposition of theory upon nature. Somehow, I am not distressed that the human order must veil all our interactions with the universe, for the veil is translucent, however strong its texture.
Postscript
Our fascination with Piltdown never seems to abate. This article, published originally in March, 1979, elicited a flurry of correspondence, some acerbic, some congratulatory. It centered, of course, upon Teilhard. I was not trying to be cute by writing at length about Teilhard while stating briefly that Dawson acting alone accounts best for the facts. The case against Dawson had been made admirably by Weiner, and I had nothing to add to it. I continued to regard Weiner’s as the most probable hypothesis. But I also believed that the only reasonable alternative (since the second Piltdown site established Dawson’s complicity in my view) was a coconspiracy—an accomplice for Dawson. The other current proposals, involving Sollas or even G.E. Smith himself, seemed to me so improbable or off-the-wall that I wondered why so little attention had focussed upon the only recognized scientist who had been with Dawson from the start—especially since several of Teilhard’s prominent colleagues in vertebrate paleontology harbored private thoughts (or had made cryptically worded public statements) about his possible role.
Ashley Montagu wrote on December 3, 1979, and told me that he had broken the news to Teilhard himself after Oakley’s revelation of the fraud—and that Teilhard’s astonishment seemed too genuine to represent dissembling: “I feel sure you’re wrong about Teilhard. I knew him well, and, in fact, was the first to tell him, the day after it was announced in The New York Times, of the hoax. His reaction could hardly have been faked. I have not the slightest doubt that the faker was Dawson.” In Paris last September, I spoke with several of Teilhard’s contemporaries and scientific colleagues, including Pierre P. Grassé and Jean Piveteau; all regarded any thought of his complicity as monstrous. Père Francois Russo, S.J., later sent me a copy of the letter that Teilhard wrote to Kenneth P. Oakley after Oakley had exposed the fraud. He hoped that this document would assuage my doubts about his coreligionist. Instead my doubts intensified; for, in this letter, Teilhard made a fatal slip. Intrigued by my new role as sleuth, I visited Kenneth Oakley in England on April 16, 1980. He showed me additional documents of Teilhard, and shared other doubts with me. I now believe that the balance of evidence clearly implicates Teilhard as a coconspirator with Dawson in the Piltdown plot. I will present the entire case in Natural History Magazine in the summer or fall of 1980; but for now, let me mention the internal evidence from Teilhard’s first letter to Oakley alone.
Teilhard begins the letter by expressing satisfaction. “I congratulate you most sincerely on your solution of the Piltdown problem…I am fundamentally pleased by your conclusions, in spite of the fact that, sentimentally speaking, it spoils one of my brightest and earliest paleontological memories.” He continues with his thoughts on “the psychological riddle,” or whodunit, he agrees with all others in dismissing Smith Woodward, but he also refuses to implicate Dawson, citing hi
s thorough knowledge of Dawson’s character and abilities: “He was a methodical and enthusiastic character…In addition, his deep friendship for Sir Arthur makes it almost unthinkable that he should have systematically deceived his associate several years. When we were in the field, I never noticed anything suspicious in his behavior.” Teilhard ends by proposing, halfheartedly by his own admission, that the whole affair might have been an accident engendered when an amateur collector threw out some ape bones onto a spoil heap that also contained some human skull fragments, (although Teilhard does not tell us how such a hypothesis could possibly account for the same association two miles away at the second Piltdown site).
Teilhard’s slip occurs in his description of the second Piltdown find. Teilhard writes: “He just brought me to the site of Locality 2 and explained me (sic) that he had found the isolated molar and the small pieces of skull in the heaps of rubble and pebbles raked at the surface of the field.” Now we know (see Weiner, p. 142) that Dawson did take Teilhard to the second site for a prospecting trip in 1913. He also took Smith Woodward there in 1914. But neither visit led to any discovery; no fossils were found at the second site until 1915. Dawson wrote to Smith Woodward on January 20, 1915 to announce the discovery of two cranial fragments. In July 1915, he wrote again with good news about the discovery of a molar tooth. Smith Woodward assumed (and stated in print) that Dawson had unearthed the specimens in 1915 (see Weiner, p. 144). Dawson became seriously ill later in 1915 and died the next year. Smith Woodward never obtained more precise information from him about the second find. Now, the damning point: Teilhard states explicitly, in the letter quoted above, that Dawson told him about both the tooth and the skull fragments of the second site. But Claude Cuénot, Teilhard’s biographer, states that Teilhard was called up for service in December, 1914; and we know that he was at the front on January 22, 1915 (pp. 22–23). But if Dawson did not “officially” discover the molar until July, 1915, how could Teilhard have known about it unless he was involved in the hoax. I regard it as unlikely that Dawson would show the material to an innocent Teilhard in 1913 and then withold it from Smith Woodward for two years (especially after taking Smith Woodward to the second site for two days of prospecting in 1914). Teilhard and Smith Woodward were friends and might have compared notes at any time; such an inconsistency on Dawson’s part could have blown his cover entirely.
Second, Teilhard states in his letter to Oakley that he did not meet Dawson until 1911: “I knew Dawson very well, since I worked with him and Sir Arthur three or four times at Piltdown (after a chance meeting in a quarry near Hastings in 1911).” Yet it is certain that Teilhard met Dawson during the spring or summer of 1909 (see Weiner, p. 90). Dawson introduced Teilhard to Smith Woodward, and Teilhard submitted some fossils he had found, including a rare tooth of an early mammal, to Smith Woodward late in 1909. When Smith Woodward described this material before the Geological Society of London in 1911, Dawson, in the discussion following Smith Woodward’s talk, paid tribute to the “patient and skilled assistance” given to him by Teilhard and another priest since 1909. I don’t regard this as a damning point. A first meeting in 1911 would still be early enough for complicity (Dawson “found” his first piece of the Piltdown skull in the autumn of 1911, although he states that a workman had given him a fragment “some years” earlier), and I would never hold a mistake of two years against a man who tried to remember the event forty years later. Still, a later (and incorrect) date, right upon the heels of Dawson’s find, certainly averts suspicion.
Moving away from the fascination of whodunit to the theme of my original essay (why did anyone ever believe it in the first place), another colleague sent me an interesting article from Nature (the leading scientific periodical in England), November 13, 1913, from the midst of the initial discussions. In it, David Waterston of King’s College, University of London, correctly (and definitely) stated that the skull was human, the jaw an ape’s. He concludes: “It seems to me to be as inconsequent to refer the mandible and the cranium to the same individual as it would be to articulate a chimpanzee foot with the bones of an essentially human thigh and leg.” The correct explanation had been available from the start, but hope, desire, and prejudice prevented its acceptance.
11 | Our Greatest Evolutionary Step
IN MY PREVIOUS book, Ever Since Darwin, I began an essay on human evolution with these words:
New and significant prehuman fossils have been unearthed with such unrelenting frequency in recent years that the fate of any lecture notes can only be described with the watchword of a fundamentally irrational economy—planned obsolescence. Each year, when the topic comes up in my courses, I simply open my old folder and dump the contents into the nearest circular file. And here we go again.
And I’m mighty glad I wrote them, because I now want to invoke that passage to recant an argument made later in the same article.
In that essay I reported Mary Leakey’s discovery (at Laetoli, thirty miles south of Olduvai Gorge in Tanzania) of the oldest known hominid fossils—teeth and jaws 3.35 to 3.75 million years old. Mary Leakey suggested (and so far as I know, still believes) that these remains should be classified in our genus, Homo. I therefore argued that the conventional evolutionary sequence leading from small-brained but fully erect Australopithecus to larger-brained Homo might have to be reassessed, and that the australopithecines might represent a side branch of the human evolutionary tree.
Early in 1979, newspapers blazed with reports of a new species—more ancient in time and more primitive in appearance than any other hominid fossil—Australopithecus afarensis, named by Don Johanson and Tim White. Could any two claims possibly be more different—Mary Leakey’s argument that the oldest hominids belong to our own genus, Homo, and Johanson and White’s decision to name a new species because the oldest hominids possess a set of apelike features shared by no other fossil hominid. Johanson and White must have discovered some new and fundamentally different bones. Not at all. Leakey and Johanson and white are arguing about the same bones. We are witnessing, debate about the interpretation of specimens, not a new discovery.
Johanson worked in the Afar region of Ethiopia from 1972 to 1977 and unearthed an outstanding series of hominid remains. The Afar specimens are 2.9 to 3.3 million years old. Premier among them is the skeleton of an australopithecine named Lucy. She is nearly 40 percent complete—much more than we have ever possessed for any individual from these early days of our history. (Most hominid fossils, even though they serve as a basis for endless speculation and elaborate storytelling, are fragments of jaws and scraps of skulls.)
Johanson and White argue that the Afar specimens and Mary Leakey’s Laetoli fossils are identical in form and belong to the same species. They also point out that the Afar and Laetoli bones and teeth represent everything we know about hominids exceeding 2.5 million years in age—all the other African specimens are younger. Finally, they claim that the teeth and skull pieces of these old remains share a set of features absent in later fossils and reminiscent of apes. Thus, they assign the Laetoli and Afar remains to a new species, A. afarensis.
The debate is just beginning to warm up, but three opinions have already been vented. Some anthropologists, pointing to different features, regard the Afar and Laetoli specimens as members of our own genus, Homo. Others accept Johanson and White’s conclusion that these older fossils are closer to the later south and east African Australopithecus than to Homo. But they deny a difference sufficient to warrant a new species and prefer to include the Afar and Laetoli fossils within the species A. africanus, originally named for South African specimens in the 1920s. Still others agree with Johanson and White that the Afar and Laetoli fossils deserve a new name.
The palate of Australopithecus afarensis (center, compared with that of a modern chimpanzee (left) and a human (right).
COURTESY OF TIM WHITE AND THE CLEVELAND MUSEUM OF NATURAL HISTORY
As a rank anatomical amateur, my opinion is worth next to nothing. Yet I
must say that if a picture is worth all the words of this essay (or only half of them if you follow the traditional equation of 1 for 1,000), the palate of the Afar hominid certainly says “ape” to me. (I must also confess that the designation of A. afarensis supports several of my favorite prejudices. Johanson and White emphasize that the Afar and Laetoli specimens span a million years but are virtually identical. I believe that most species do not alter much during the lengthy period of their success and that most evolutionary change accumulates during very rapid events of splitting from ancestral stocks—see essays 17 and 18. Moreover, since I depict human evolution as a bush rather than a ladder, the more species the merrier. Johanson and White do, however, accept far more gradualism than I would advocate for later human evolution.)
Amidst all this argument about skulls, teeth, and taxonomic placement, another and far more interesting feature of the Afar remains has not been disputed. Lucy’s pelvis and leg bones clearly show that A. afarensis walked as erect as you or I. This fact has been prominently reported by the press, but in a very misleading way. The newspapers have conveyed, almost unanimously, the idea that previous orthodoxy had viewed the evolution of larger brains and upright postures as a gradual transition in tandem, perhaps with brains leading the way—from pea-brained quadrupeds to stooping half brains to fully erect, big-brained Homo. The New York Times writes (January 1979): “The evolution of bipedalism was thought to have been a gradual process involving intermediate forerunners of modern human beings that were stooped, shuffle-gaited ‘ape-men,’ creatures more intelligent than apes but not as intelligent as modern human beings.” Absolutely false, at least for the past fifty years of our knowledge.
The Panda's Thumb: More Reflections in Natural History Page 11