LATER DISCOVERIES IN JAVA

LATER DISCOVERIES IN JAVA

Meganthropus was the last major discovery reported by von Koenigswald, but the search for more bones of Java man has continued up to the present. These later finds, reported by P. Marks, T. 17417c216r Jacob, S. Sartono, and others, are uniformly accepted as evidence for Homo erectus in the Javanese Middle and Early Pleistocene. Like the discoveries of von Koenigswald, these fossils were almost all found on the surface by native collectors or farmers.

For example, T. Jacob reported that in August 1963 an Indonesian farmer discovered fragments of a fossilized skull in the Sangiran area while working in a field. When assembled, these skull fragments formed what appeared to be a skull similar to the type that is designated as Homo erectus. Although Jacob asserted that this skullcap was from the Middle Pleistocene Kabuh formation, he did not state the exact position of the fragments when found. All we really know is that a farmer discovered some fossil skull fragments that were most likely on or close to the surface.

In 1973, Jacob made this interesting remark about Sangiran, where all of the later Java Homo erectus finds were made: "The site seems to be still promising, but presents special problems- This is mainly due to the site being inhabited by people, many of whom are collectors who had been trained in identifying important fossils. Chief collectors always try to get the most out of the Primate fossils found accidentally by primary discoverers. In addition, they may not report the exact site of the find, lest they lose one potential source of income. Occasion­ally, they may not sell all the fragments found on the first purchase, but try to keep a few pieces to sell at a higher price at a later opportunity."

Nevertheless, the Sangiran fossils are accepted as genuine. If anomalously old human fossils were found in situations like this, they would be subjected to merciless criticism. As always, our point is that a double standard should not be employed in the evaluation of paleoanthropological evidence-an impossibly strict standard for anomalous evidence and an exceedingly lenient standard for acceptable evidence.

In order to clear up uncertainties, letters were written in 1985 to both S. Sartono and to T. Jacob for further information about discoveries reported by them from Java. No answers were received..

CHEMICAL AND RADIOMETRIC DATING OF THE JAVA FINDS

We shall now discuss issues related to the potassium-argon dating of the formations yielding hominid fossils in Java, as well as attempts to date the fossils themselves by various chemical and radiometric methods.

The Kabuh formation at Trinil, where Dubois made his original Java man finds, has been given a potassium-argon age of 800,000 years. Other finds in Java came from the Djetis beds of the Putjangan formation. According to T. Jacob, the Djetis beds of the Putjangan formation near Modjokerto yielded an Early Pleis­tocene potassium-argon date of about 1.9 million years. The date of 1.9 million years is significant for the following reasons. As we have seen, many Homo erectus fossils (previously designated Pithecanthropus and Meganthropus) have been assigned to the Djetis beds. If these fossils are given an age of 1.9 million years, this makes them older than the oldest African Homo erectus finds, which are about 1.6 million years old. According to standard views, Homo erectus evolved in Africa and did not migrate out of Africa until about 1 million years ago.

Also, some researchers have suggested that von Koenigswald's Meganthropus might be classified as Australopithecus. If one accepts this opinion, this means that Javan representatives of Australopithecus arrived from Africa before 1.9 million years ago or that Australopithecus evolved separately in Java. Both hypotheses are in conflict with standard views on human evolution.

It should be kept in mind, however, that the potassium-argon technique that gave the 1.9-million-year date is not foolproof. T. Jacob and G. Curtis, who attempted to date most of the hominid sites in Java, found it difficult to obtain meaningful dates from most samples. In other words, dates were obtained, but they deviated so greatly from what was expected that Jacob and Curtis had to attribute the unsatisfactory results to contaminants. In 1978, G. J. Bartstra reported a potassium-argon age of less than 1 million years for the Djetis beds.

We have seen that the Trinil femurs are indistinguishable from those of modern humans and distinct from those of Homo erectus. This has led some to suggest that the Trinil femurs do not belong with the Pithecanthropus skull and were perhaps mixed into the early Middle Pleistocene Trinil bone bed from higher levels. Another possibility is that anatomically modern humans were living alongside ape-man-like creatures during the early Middle Pleistocene in Java. In light of the evidence presented in this book, this would not be out of the question.

The fluorine content test has often been used to determine if bones from the same site are of the same age. Bones absorb fluorine from ground waters, and thus if bones contain similar percentages of fluorine (relative to the bones' phosphate content) this suggests such bones have been buried for the same amount of time.

In a 1973 report, M. H. Day and T. I. Molleson analyzed the Trinil skullcap and femurs and found they contained roughly the same ratio of fluorine to phosphate. Middle Pleistocene mammalian fossils at Trinil contained a fluorine-to-phosphate ratio similar to that of the skullcap and femurs. Day and Molleson stated that their results apparently indicated the contemporaneity of the calotte and femora with the Trinil fauna.

If the Trinil femurs are distinct from those of Homo erectus and identical to those of Homo sapiens sapiens, as Day and Molleson reported, then the fluorine content of the femurs is consistent with the view that anatomically modern humans existed in Java during the early Middle Pleistocene, about 800,000 years ago.

Day and Molleson suggested that Holocene (recent) bones from the Trinil site might, like the Java man fossils, also have fluorine-to-phosphate ratios similar to those of the Middle Pleistocene animal bones, making the fluorine test useless here. K. P. Oakley, the originator of the fluorine content testing method, pointed out that the rate of fluorine absorption in volcanic areas, such as Java, tends to be quite erratic, allowing bones of widely differing ages to have similar fluorine contents. This could not be directly demonstrated at the Trinil site, because there only the Middle Pleistocene beds contain fossils.

Day and Molleson showed that Holocene and Late Pleistocene beds at other sites in Java contained bones with fluorine-to-phosphate ratios similar to those of the Trinil bones. But they admitted that the fluorine-to-phosphate ratios of bones from other sites "would not be directly comparable" with those of bones from the Trinil site. This is because the fluorine absorption rate of bone depends upon factors that can vary from site to site. Such factors include the groundwater's fluorine content, the groundwater's rate of flow, the nature of the sediments, and the type of bone.

Therefore, the fluorine content test results reported by Day and Molleson remain consistent with (but are not proof of) an early Middle Pleistocene age of about 800,000 years for the anatomically modern human Trinil femurs.

A nitrogen content test was also performed on the Trinil bones. Dubois had boiled the skullcap and the first femur in animal glue, the protein of which contains nitrogen. Day and Molleson attempted to correct for this by pre-treating the samples in order to remove soluble nitrogen before analysis. Results showed that the Trinil bones had very little nitrogen left in them. This is consistent with all of the bones being of the same early Middle Pleistocene age, although Day and Molleson did report that nitrogen in bone is lost so rapidly in Java that even Holocene bones often have no nitrogen.

MISLEADING PRESENTATIONS OF THE JAVA MAN EVIDENCE

Most books dealing with the subject of human evolution present what appears at first glance to be an impressive weight of evidence for Homo erectus in Java between 0.5 and 2.0 million years ago. One such book is The Fossil Evidence for Human Evolutional?,), by W. E. Le Gros Clark, professor of anatomy at Oxford University, and Bernard G. Campbell, adjunct professor of anthropology at the University of California at Los Angeles. An impressive table showing discoveries of Homo erectus is presented in their book. These discoveries have been used widely to support the belief that man has evolved from an apelike being.

T3 is the femur found by Dubois at a distance of 45 feet from the original cranium, T2. We have already discussed how unjustified it is to assign these two bones to the same individual. Yet ignoring many important facts, Le Gros Clark and Campbell stated that "the accumulation of evidence speaks so strongly for their natural association that this has become generally accepted."

T6, T7, T8, and T9 are the femurs found in boxes of fossils in Holland over 30 years after they were originally excavated in Java. Le Gros Clark and Campbell apparently ignored Dubois's statement that he himself did not excavate them, and that the original location of the femurs was unknown. Furthermore, von Koenigswald stated that the femurs were from Dubois's general collection, which contained fossils from "various sites and various ages which are very inadequately distin­guished because some of the labels got lost." Nevertheless, Le Gros Clark and Campbell assumed that these femurs came from the Trinil beds of the Kabuh formation. But Day and Molleson observed: "If the rigorous criteria that are demanded in modern excavations were applied to all of the Trinil material subsequent to the calotte and Femur I, it would all be rejected as of doubtful provenance and unknown stratigraphy."

Fossil Ml and fossils S1a through S6 are those discovered by Javanese native collectors employed by von Koenigswald. Only one of them (Ml) was reported to have been discovered buried in the stratum to which it is assigned, and even this report is subject to question. The remaining fossils of the S series are the ones reported by Marks, Sartono, and Jacob, and the majority of these were surface finds by villagers and farmers, who sold the fossils, perhaps by way of middlemen, to the scientists. One familiar with the way these specimens were found can only wonder at the intellectual dishonesty manifest in Table 8.1, which gives the impression that the fossils were all found in strata of definite age.

Le Gros Clark and Campbell noted that the real location of many of von Koenigswald's finds was unknown. Nevertheless, they said that the fossils must have come from Middle Pleistocene Trinil beds of the Kabuh formation (0.7-1.3 million years old) or the Early Pleistocene Djetis beds of the Putjangan formation (1.3-2.0 million years old).

The ages given by Le Gros Clark and Campbell, derived from the potassium-argon dates discussed previously, refer only to the age of the volcanic soils, and not to the bones themselves. Potassium-argon dates have meaning only if the bones were found securely in place within or beneath the layers of dated volcanic material. But the vast majority of fossils listed in Table 8.1 were surface finds, rendering their assigned potassium-argon dates meaningless.

Concerning the age of 1.3-2.0 million years given by Le Gros Clark and Campbell for the Djetis beds of the Putjangan formation, we note that this is based on the potassium-argon date of 1.9 million years reported by Jacob and Curtis in 1971. But in 1978 Bartstra reported a potassium-argon age of less than 1 million years. Other researchers have reported that the fauna of the Djetis and Trinil beds are quite similar and that the bones have similar fluorine-to-phosphate ratios.

Le Gros Clark and Campbell concluded that "at this early time there existed in Java hominids with a type of femur indistinguishable from that of Homo sapiens, though all the cranial remains so far found emphasize the extraordinarily primitive

characters of the skull and dentition." All in all, the presentation by Le Gros Clark and Campbell was quite misleading. They left the reader with the impression that cranial remains found in Java can be definitely associated with the femurs when such is not the case. Furthermore, discoveries in China and Africa have shown that Homo erectus femurs are different from those collected by Dubois in Java.

Judging strictly by the hominid fossil evidence from Java, all we can say is the following. As far as the surface finds are concerned, these are all cranial and dental remains, the morphology of which is primarily apelike with some humanlike features. Because their original stratigraphic position is unknown, these fossils simply indicate the presence in Java, at some unknown time in the past, of a creature with a head displaying some apelike and humanlike features.

The original Pithecanthropus skull (T2) and femur (T3) reported by Dubois were found in situ, and thus there is at least some basis for saying they are perhaps as old as the early Middle Pleistocene Trinil beds of the Kabuh formation. The original position of the other femurs is poorly documented, but they are said to have been excavated from the same Trinil beds as T2 and T3. In any case, the original femur (T3), described as fully human, was not found in close connection with the primitive skull and displays anatomical features that distinguish it from the femur of Homo erectus. There is, therefore, no good reason to connect the skull with the T3 femur or any of the other femurs, all of which are described as identical to those of anatomically modern humans. Consequently, the T2 skull and T3 femur can be said to indicate the presence of two kinds of hominids in Java during the early Middle Pleistocene-one with an apelike head and the other with legs like those of anatomically modern humans. Following the typical practice of giving a species identification on the basis of partial skeletal remains, we can say that the T3 femur provides evidence for the presence of Homo sapiens sapiens in Java around 800,000 years ago. Up to now, no creature except Homo sapiens sapiens is known to have possessed the kind of femur found in the early Middle Pleistocene Trinil beds of Java.