Niah Caves are located in a limestone mountain, Gunung Subis, within the Miri Division, Sarawak, Malaysia. The massive cave entrance is located at the western end of the cave complex. The caves were discovered by Europeans in 1950, purchased by the Sarawak Museum, and large-scale archaeological excavations conducted by Tom and Barbarra Harrisson between 1954 and 196?. The archaeological deposits extend from the late Pleistocene to the recent Neolithic. Thousands of artifacts and animal bones, as well as a large number of Neolithic human burials were excavated by the Harrisson team. Many preliminary reports and specialist papers were published by Tom Harrisson (1957, 1958a, 1958b,…) and his collaborators, but a comprehensive description of the excavations, with details of stratigraphy was not completed (Barker et al. 2007). Even under the best of circumstances it can be difficult to excavate and interpret stratigraphic relationships in cave deposits. Apart from the large scale of the Niah Cave excavation, the Harrison’s were not trained archaeologists, the cave had been used by humans for thousands of years, deposits and stratigraphy had been disturbed by flooding, bioturbation and treadage had probably moved objects through the stratigraphic profile, record-keeping and excavation methods were not ideal and comprehensive reports not completed. More recently, a monumental effort by Graeme Barker and colleagues (2007) has focused on sorting out the dating and stratigraphic relationships of the Niah Cave and has reinforced the importance of the cave in providing an understanding of 40,000 years of human behaviour in this part of southeast Asia.
In 1958 the so-called Deep Skull was excavated at Niah and given to Donald Brothwell (1960) for reconstruction and description. Charcoal collected near the location of the skull had been radiocarbon dated to approximately 40,000 years, making this the earliest example of a modern human from anywhere in the world. Unfortunately, the cranium was poorly preserved, with a distorted and incomplete cranial vault and facial skeleton. Some incomplete postcranial bones, including a femur, were found near the cranium and thought to be from the same individual. Brothwell’s (1960) description made it clear that Niah was an anatomically modern human, but he was uncertain as to the age at death, sex or ethnic affiliation. This was early in Brothwell’s career and he had very limited familiarity with geographically and temporally relevant skeletal materials. Indeed, this is a problem that is also apparent in more recent attempts to describe Niah.
Reconstruction of the "deep skull" showing distortion and poor preservation
Brothwell estimated that Niah was 15-17 years old when she died. While the cranium appeared to have an obliterated spheno-occipital suture, there was also an unerupted third molar, suggesting that Niah might not be an adult. The cranium and facial skeleton were also small in size, with relatively delicate anatomical features. To add to this uncertainty, while the 3rd molar had not erupted, occlusal wear on the remaining maxillary first molar was advanced.
While it used to be thought that fusion of the spheno-occiptal suture indicated that growth of the facial skeleton and vault had ceased, it is now known that fusion can occur as early as 11-years in girls (Krishnan and Kanchan 2013). Therefore, it is not a reliable indicator of adult status. It is also known that unerupted, impacted and congenitally absent third molars have a relatively high frequency in modern Asian populations (Sujo et al. 2016; Kanneppady et al. 2013) and also in the Neolithic. Without the associated mandible and left maxillary teeth, a single unerupted third molar is not a reliable indicator of age. A closer look at the dentitions of the Neolithic burials from the cave might also have been informative.
Comparison of occlusal tooth wear in the maxillary first and second molar teeth of a mid-Holocene Australian and Niah. The right side of the image, has an outline of the occlusal surface area of the crown and exposed dentine, with perecentages of dentine area to crown area (copyright Peter Brown).
In human Late Pleistocene, and more recent hunter-gatherer populations, tooth wear proceeded at a much greater rate than in later agricultural and urban groups. On the occlusal (chewing) surfaces of the teeth, a combination of tooth-to-tooth contact and tough/abrasive food, with limited pre-masticatory preparation, resulted in the relatively rapid loss of dental enamel. With the loss of enamel, the underlying softer dentine is exposed, and the teeth wear even more quickly. Human populations with a similar diet and forms of masticatory and non-masticatory tooth use tend to have broadly similar patterns of occlusal tooth wear. The first molar teeth which erupt at around 6 years of age, will have more occlusal wear than the second molars that erupt at 12 years of age. Both will have more occlusal wear than the third molar, which usually reaches occlusion >16 years. The extent of wear on the occlusal surface of the molar teeth has been used to give an estimate of age at death (Lovejoy 1985; Miles 2001). These age estimation methods are going to be population specific, as was the interaction of teeth with the masticatory environment during life (Brown 1992).
A scatter plot of occlusal wear (log 10 dentine area x 100/occlusal area) for the first molar against the second molar can provide a tooth wear gradient. The scatter plot below demonstrates this with the total Australian terminal Pleistocene-early Holocene sample from south-eastern Australia (Brown 1992). Niah and a mid-Holocene Australian (HA) have been added to the plot. This highlights the minimal amount of wear on the Niah second molar relative to the first. Without a mandible, or teeth from the left side of the maxilla, you can only speculate why this might be. For instance, the corresponding molar on the right side of the mandible might have been lost, or eruption of teeth delayed. Regardless, the large amount of wear on the first molar was undoubtedly associated with anterior teeth (premolars, canines and incisors) that were also heavily worn as in HA. Niah was an older adult, not in her teens or early 20’s, perhaps 30-40.
A more major concern with the “Deep Skull” has been whether it is contemporaneous with the dated charcoal. The skull itself had not been directly dated and subsequently several authors have argued that it was most likely part of an intrusive Neolithic burial (Kennedy 1979; Wolpoff 1999; Solheim 1983). Most recently, Barker and colleagues (2007) have reviewed the historical records for the original excavations, gathered new information from the site, and applied U-series dating to fragments of bone from the Niah cranium. They obtained a U-series date of ~35 kyrs and the authors think that this might be an underestimate. In the past U-series dating of bone has been considered problematic due to the possibility of variable rates post-depositional uranium uptake (Hercman 2017). At some archaeological and paleontological sites, U-series and C14/AMS pairs on bones/teeth have provided consistent date ranges, at other sites it has not been successful. If Barker et al. (2007) dates are meaningful, then the Niah cranium is younger than the earliest anatomically modern Homo sapiens from Europe.However, the eariest evidence of human occupation at Niah may be slightly older than ~40 kyrs.
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