A publication of the Archaeological Institute of America
Poloyo cranium with facial reconstruction(Vito Cannella)
A rare skull of a Homo erectus from Poloyo in the Solo River area of central Java has been found among a collection of curiosities sold to a Manhattan boutique. The cranium (the maxilla and mandible are both missing) may date to between 100,000 to 1.5 million years ago. Clearly defined sutures in the skullcap and overall thickness of the cranial bones suggested that the person was a young adult, and, with highly developed masticatory muscles, most likely male.
Just how it found its way to New York's Upper West Side remains a mystery. According to Henry Galiano, owner of Maxilla and Mandible, Ltd., which specializes in natural history relics--fossils, bones, mounted insects, and ostrich eggs--the skull was in a large crate of rocks, minerals, and tribal curios from Indonesia that was dropped off at his store last March by a man claiming to represent a collector's estate.
"I bought the whole lot based on the value of the minerals alone," says Galiano, who would not disclose the amount paid for the collection. "I was surprised when I came across the skull, which was caked in mud, probably applied to camouflage the fossil for export. Once I cleaned the mud off and began preparing the fossil for display it was clear to me that the skull was quite early and probably of some importance." According to Galiano, he ran into Eric Delson, an old friend and researcher at the American Museum of Natural History, which is located a block away, and invited him in for a look. "At first," said Galiano, who regularly prepares fossils for display for the American Museum, "we thought the skull might actually be that of Peking Man." That and other H. erectus fossils unearthed at Zhoukoudian, near Beijing, disappeared shortly after being entrusted to a platoon of U.S. Marines during the Second World War.
According to paleoanthropologist Teuku Jacob of Gadjah Mada University in Jogjakarta, who has since taken the specimen back to Indonesia, the cranium was found in 1997 during sand mining in the middle and from the bottom of the Solo River in the Sambungmachan District between the villages of Poloyo and Chemeng. It bears the designation Sm 3 after its findspot, which has yielded two other fossils--Sambungmachan 1 a skull and Sambungmachan 2, a tibidal fragment. Animal fossils were also obtained by the workers, similar to the fauna associated with Sm 1. The cranium was studied briefly by physical anthropologist Boedhihartono, who was asked to verify the genuineness and importance of the fossil, and who later published his preliminary study in the journal Antropologi (Jakarta, 1997) and presented his findings at a national archaelogical colloquium in Surakarta in 1998. The skull has been almost totally cleaned when he studied it, and his description and conclusion are quite correct. He noted the resemblances showed by the skull with those of the Ngandong skulls, and at the same time the differences.
"A "professional" collector who has had a few troubles with the law in the past," says Jacob, "sold it to a foreign antiques' dealer in Jakarta, who also has had legal problems associated with smuggling antiques and fossils abroad and finally it arrived in New York. The original discoverer was paid US$3.
Scholars have remarked on the unusualness of the cranium, citing a mix of H. erectus traits, such as a thick cranial bone and a pronounced browridge, and features commonly observed in more recent humans, such as a high forehead, and rounded braincase. Columbia University paleoneurologist Ralph Holloway, who, along with his graduate student, Doug Broadfield, is analyzing an endocast, a mold taken from the inside of the cranium, has also noted that, despite the individual's small cranial capacity, ca. 900cc compared to the 1200cc of archaic H. sapiens, the layout of the brain, etched in the interior of the fossil, has some strikingly modern characteristics. These include an asymetrical development of the left and right hemispheres of the brain and evidence of a so-called Broca's Cap, or bump on the left side which indicates the possibility of speech.
"The skull is small (ca. 875 cc), but otherwise the likeness to Homo erectus soloensis from Ngandong is striking," says Jacob, "especially in the sagittal contour. It is certainly not Homo sapiens and the antiquity could be around 100 000 years. For a male young adult the size is too small for H. erectus soloensis, but other qualitative features deviate from Sangiran H. erectus erectus. From my viewpoint the new skull should be classified with Ngandong rather than with the older fossils from Sangiran and Trinil."
Ken Mowbray of the American Museum of Natural History and Rutgers University, believes, however, that the seemingly modern features of the new-found skull fall within the range of Southeast Asian H. erectus. "It is possible that the Poloyo fossil is nothing more than a developmental variant of H. erectus that has a globular shaped vault due to having a wider cranial base in comparison to its length. However, we cannot rule out the possibility that a few traits such as the rising forehead and diminished brow, commonly associated with more recent species, may be indicators that we are looking at a quite different population living along the Solo River. Only after an exhaustive comparison with Indonesian and Chinese fossils will we be able to answer these questions."
"For me," says Susan Antón of the University of Florida, who examined the fossil in July, "the skullcap is a unifying specimen because it combines characteristics seen in both the older [1.6. million years] and younger [less than 100,000 years] H. erectus groups in Southeast Asia. Previously, some paleoanthropologists had considered the younger specimens from Indonesia, such as those from Ngandong, as possibly separate species from the older speciment, such as those from Sangiran and Trenil. This distinction has been based largely on the larger brains at Ngandong and on specific features, some of which were thought to be related to brain size, that were thought to differ at Ngandong. But in the Poloyo skullcap, even though its cranial capacity is similar to the smaller of the H. erectus specimens from Sangiran, there are also features commonly associated with the much larger brained, geologically younger Ngandong specimens including the very broad frontal (forehead) formerly attributed to expansion in brain size, details of the browridge, and relationships between muscular attachments on the temperal bone, and details of the occipital torus on the back of the vault. Thus, this specimen, whatever its geological age, argues for a general morphological unity amongst all the Southeast Asian H. erectus, that while it may have varied slightly from population to population was maintained in the region for a long time."
Reconstruction of the Poloyo hominid(Vito Cannella)
Based on the features mentioned above, Anton and Mowbray think that the cranium fits better with the younger Southeast Asian like Ngandong, despite its small brain size, rather than the most ancient. "My guess," said Carl Swisher III of the Berkeley Geochronology Center, who is currently dating the traces of sediment that Galiano had carefully removed from the skull, "is that it a geologically young H. erectus." He notes, however, that it will be difficult to determine the precise age of the cranium since it appeared on the scene out of context. "As we can only guess at its findspot," says Swisher, "we must rely on what we can learn from the sediment found inside." Swisher, who has just returned to Indonesia, will update ARCHAEOLOGY as new information becomes available.
Angela M.H. Schuster is a senior editor of ARCHAEOLOGY.