THE SELENKA EXPEDITION

THE SELENKA EXPEDITION

To resolve some of the questions surrounding the Pithecanthropus fossils and their discovery, Emil Selenka, professor of zoology at Munich University in Germany, prepared a full-fledged expedition to Java, but he died before it departed. His wife, P 444p1524e rofessor Lenore Selenka, took over the effort and con­ducted excavations at Trinil in the years 1907-1908, employing 75 laborers to hunt for more Pithecanthropus erectus fossils. Altogether, Selenka's team of geologists and paleontologists sent back to Europe 43 boxes of fossils, but they included not a single new fragment of Pithecanthropus. The expedition did, however, find in the Trinil strata signs of a human presence-splintered animal bones, charcoal, and foundations of hearths. Signs like this led Lenore Selenka to conclude that humans and Pithecanthropus erectus were contemporary. The implications of all this for an evolutionary interpretation of Dubois's Pithecan­thropus specimens were, and still are, unsettling.

Furthermore, in 1924 George Grant MacCurdy, a Yale professor of anthropol­ogy, wrote in his book Human Origins: "The Selenka expedition of 1907- 1908 ... secured a tooth which is said by Walkoff to be definitely human. It is a third molar from a neighboring stream bed and from deposits older (Pliocene) than those in which Pithecanthropus erectus was found."

DUBOIS WITHDRAWS FROM THE BATTLE

Meanwhile, the status of Dubois's ape-man remained controversial. Survey­ing the range of opinion about Pithecanthropus, Berlin zoologist Wilhelm Dames gathered statements from several scientists: three said Pithecanthropus was an ape, five said it was human, six said it was an ape-man, six said it was a missing link, and two said it was a link between the missing link and man.

But while many scientists maintained their doubts, others followed Haeckel in hailing Java man as stunning proof of Darwin's theory. Some used Java man to discredit evidence for a fully human presence in the Tertiary. As we learned in Chapter 5, W. H. Holmes dismissed discoveries of stone tools in the Tertiary auriferous gravels of California because "they implied a human race older by at least one-half than Pithecanthropus erectus of Dubois, which may be regarded as an incipient form of human creature only."

At a certain point, Dubois became completely disappointed with the mixed reception the scientific community gave to his Pithecanthropus. He stopped showing his specimens. Some say that he kept them for some time beneath the floorboards in his home. In any case, they remained hidden from view for some 25 years, until 1932.

During and after the period of withdrawal, the controversies concerning Pithecanthropus continued. Marcellin Boule, director of the Institute of Human Paleontology in Paris, reported, as had other scientists, that the layer in which the Pithecanthropus skullcap and femur were said to have been found contained numerous fossil bones offish, reptiles, and mammals. Why, there­fore, should anyone believe the skullcap and femur came from the same individual or even the same species? Boule, like Virchow, stated that the femur was identical to that of a modern human whereas the skullcap resembled that of an ape, possibly a large gibbon. In 1941, Dr. F. Weidenreich, director of the Cenozoic Research Laboratory at Beijing Union Medical College, also stated that there was no justification for attributing the femur and the skullcap to the same individual. The femur, Weidenreich said, was very similar to that of a modern human, and its original position in the strata was not securely established. Modern researchers have employed chemical dating techniques to determine whether or not the original Pithecanthropus skull and femur were both contemporary with the Middle Pleistocene Trinil fauna, but the results were inconclusive.

MORE FEMURS

The belated revelation that more femurs had been discovered in Java further complicated the issue. In 1932, Dr. Bernsen and Eugene Dubois recovered three femurs from a box of fossil mammalian bones in the Leiden Museum in the Netherlands. The box contained specimens said to have been excavated in 1900 by Dubois's assistant, Mr. Kriele, from the same Trinil deposits on the left bank of the Solo river that had yielded Dubois's first Java man finds. Dr. Bernsen died very shortly thereafter, without providing further information about the details of this museum discovery.

Dubois stated that he was not present when the femurs were taken out by Kriele. Therefore the exact location of the femurs in the excavation, which was 75 meters (246 feet) long by 6-14 meters (20-46 feet) wide, was unknown to him. According to standard paleontological procedures, this uncertainty greatly re­duces the value of the bones as evidence of any sort. Nevertheless, authorities later assigned these femurs to a particular stratum without mentioning the dubious circumstances of their discovery in boxes of fossils over 30 years after they were originally excavated. In addition to the three femurs found by Kriele, two more femoral fragments turned up in the Leiden Museum.

The existence of the additional femurs has important implications for the original Pithecanthropus skull and femur found by Dubois in the 1890s. The apelike skull and humanlike femur were found at a great distance from each other, but Dubois assigned them to the same creature. He suggested that the bones were found separated because Pithecanthropus had been dismembered by a crocodile. But if you throw in more humanlike femurs, that argument loses a great deal of its force. Where were the other skulls? Were they apelike skulls, like the one found? And what about the skull that was found? Does it really go with the femur that was found 45 feet away ? Or does it belong with one of the other femurs that later turned up? Or maybe with a femur of an entirely different sort?

ARE THE TRINIL FEMURS MODERN HUMAN?

In 1973, M. H. Day and T. I. Molleson concluded that "the gross anatomy, radiological [X-ray] anatomy, and microscopical anatomy of the Trinil femora does not distinguish them significantly from modern human femora." They also said that Homo erectus femurs from China and Africa are anatomically similar to each other, and distinct from those of Trinil.

In 1984, Richard Leakey and other scientists discovered an almost complete skeleton of Homo erectus in Kenya. Examining the leg bones, these scientists found that the femurs differed substantially from those of modern human beings.

About the Java discoveries, the scientists stated: "From Trinil, Indonesia, there are several fragmentary and one complete (but pathological) femora. Despite the fact that it was these specimens that led to the species name [Pithecanthropus erectus], there are doubts as to whether they are H. erectus with the most recent consensus being that they probably are not."

In summary, modern researchers say the Trinil femurs are not like those of Homo erectus but are instead like those of modern Homo sapiens. What is to be made of these revelations? The Java thighbones have traditionally been taken as evidence of an ape-man (Pithecanthropus erectus, now called Homo erectus) existing around 800,000 years ago in the Middle Pleistocene. Now it appears we can accept them as evidence for anatomically modern humans existing 800,000 years ago.

Some have said that the femurs were mixed in from higher levels. Of course, if one insists that the humanlike Trinil femurs were mixed in from higher levels, then why not the Pithecanthropus skull as well? That would eliminate entirely the original Java man find, long advertised as solid proof of human evolution.

Indeed, late in his life Eugene Dubois himself concluded that the skullcap of his beloved Pithecanthropus belonged to a large gibbon, an ape not thought by evolutionists to be closely related to humans. But the heretofore skeptical scientific community was not about to say good-bye to Java man, for by this time Pithecanthropus was firmly entrenched in the ancestry of modern Homo sapiens. Dubois's denials were dismissed as the whims of a cantankerous old man. If anything, the scientific community wanted to remove any remaining doubts about the nature and authenticity of Java man. This, it was hoped, would fortify the whole concept of Darwinian evolution, of which human evolution was the most highly publicized and controversial aspect.

Visitors to museums around the world still find models of the Trinil skullcap and femur portrayed as belonging to the same Middle Pleistocene Homo erectus individual. In 1984, the much-advertised Ancestors exhibit, at the Museum of Natural History in New York, brought together from around the world the major fossil evidence for human evolution, including prominently displayed casts of the Trinil skullcap and femur.