The Pitcairn Perspectives by Philip Spires - HTML preview

Discussion paper on recent finds in the Mabala Cave complex, Sawu Island, Indonesia - Was Flores Man a regional inhabitant, or is it time to name Sawu man as a separate species? - Professor Edward Pitcairn PhD, Hackney Metro University and Universitas Negeri Yogyakarta

(Draft - Further detail and references to follow)

Abstract

Archaeological excavations have been taking place in the vicinity of Mabala Cave on Sawu for over two decades. Stone tools have been located and catalogued. In recent years, there have emerged more extensive remains of humanoid habitation and bone fragments have been identified. These fragments have recently been prepared for analysis; an unusually lengthy restoration time being required because of the extremely fragile nature of the finds. This paper describes the characteristics of the bone fragments and compares them to remains found on Flores. It also examines evidence of cultural links via lithic analysis of stone tools across the two islands. It concludes that there exists a strong possibility that the Sawu finds represent either a close relative of Flores Man on Sawu in prehistoric times or may suggest that the two locations were inhabited by the same species of hominid. Further questions arise if this proves to be the case.

Background

Archaeological work on Sawu Island began in the nineties, before the detailed findings from Flores were published. By 2010, the work had located several sites of interest in or near to the Mabala complex. Because the area was becoming more popular as a tourist destination, work progressed slowly because permission to conduct research at the site was slow to arrive and then the dig was restricted to just a few months during the wet season to coincide with low tourist footfall.

Geographically, Sawu also presents the researcher with some unique challenges. Drier than most other parts of Indonesia, it does have the advantage of a significant and dependable dry season, which might suggest that prehistoric material might be better preserved there than on Flores, which is wetter for longer.

In fact, the distinct separation of wet and dry on Sawu achieves the opposite effect, since the wet season regularly washes away dried-out soil layers, with obviously the most recent layers being destroyed first. Newly exposed layers tend to be volcanic, suggesting that this washing away of new deposits has been happening for some time, since the normal processes of sedimentation do not seem to have happened across large areas of the island. The obvious consequence is that new material laid down has always had a significant chance of being washed away from the site before it has had time to embed in sediment, let alone fossilize.

Secondly, Sawu is sufficiently wet and tropical to render samples which do remain both fragile and decomposed. As on Flores, samples of organic material have generally been rendered into a substance that resembles wet cardboard. Once unearthed, they dry quickly and disintegrate, falling within days to dust, meaning that such finds need to be handled both quickly and with extreme care. As soon as they are transportable, they have to be taken immediately to a laboratory where they can be dried slowly in a humidity-controlled environment before being treated with plasticising stabilizers. Because of these constraints, none of the organic material has yet been examined for DNA analysis. It is also highly unlikely that a suitable sample for such analysis will be obtained in the near future. The essential method of handling the samples has unfortunately been a constant hindrance to the process of radio-carbon dating.

To date, work has been conducted for approximately four months each year, with analysis and measurement data being collected for some six months each year. In addition, the facilities used by the project in Yogyakarta are effectively closed for the two remaining months because of national and religious holidays. Much of the team’s time and effort has of necessity been devoted to the preservation process mentioned above, a process which has proved to be extremely time consuming. Lithic analysis of stone tools is, by its nature, also slow, but the techniques used for such specimens are the standard ones and there now exists a significant and now sufficiently extensive database of documented finds to allow statistically valid interrogation. Some preliminary results of the process will follow.

Thus far, the material published by the Sawu researchers has concentrated on the methodology and process involved in the excavation. This is entirely to be expected because of the paucity of material catalogued to date. But now there is sufficient data to allow analysis, more detailed discussion papers will surely emerge with this introductory paper being the first attempt.

Lithic analysis

It is not the purpose of this paper to present a detailed and technical analysis of the stone tool characteristics discovered in the Sawu excavations. This will be addressed in subsequent papers. What will be offered here, however, is an overview which will offer a context within which more detailed discussion can take place.

To date, we have catalogued 157 artifacts, mostly small (less than 25 millimetres in length) and mostly made from the volcanic material that forms the harder and less easily washed off layers of the island’s geology. Some of the items, just ten, are larger, and range from hand hammers to fragments of what appear to be harpoons or spears. No complete examples of larger items have been found, only fragments that do suggest they were originally part of more substantial objects.

Artefacts display more than one modal style, indicating that they may have originated from different periods or that different production systems were being used at the same time. Stone tools such as knives, blades or scrapers are often finely shaped, indicating that several knaps at the core material have been employed. There is also evidence that sharp edges were honed to improve their quality, which itself indicates a level of sophistication and skill that belies the classification of these cultures as merely hominid.

Rough dating of these finds is all that has been possible, but it is likely that none of the tools in the database is newer than 40,000 years old. This data cannot be described as reliable, since it has been achieved via evidence gleaned from miniscule deposits of organic material in the vicinity of the find and occupying the same strata level. Given the tendency of the island’s climate to wash away newly deposited material each year, however, the association between the object and its strata may be no more than circumstantial.

What seems to be clear, however, is that the material discovered thus far in the Sawu excavations is in both character and construction similar to that found on Flores, material that has been associated with Flores man. The concept of similarity applied here, of course, is that there exists nothing from Sawu that differs significantly from the Flores artefacts. There is currently insufficient evidence to claim actual concordance.

Organic remains

As mentioned earlier, the recovery and preservation of human material from the Sawu site has posed many technical problems, which have only been acceptably solved in recent years. The dig has catalogued twenty finds, of which the first ten were lost to degradation and disintegration. Everything, of course, was photographed and documented, so even the lost specimens can be analysed in terms of anatomical characteristics.

The specimens comprise arm or wrist bone fragments (six), leg or foot bone fragments (five), vertebrae fragments (eight) and a single pelvic fragment. No specimen relating to the head has yet emerged. These specimens, however, are consistent with the ‘hobbit’ stature of Flores man, a hominid of about one metre in height. Compelling here is the fact that no larger bone specimens have been unearthed, so these are probably remains of individuals of the Flores man type, rather than juveniles of Homo habilis or Homo sapiens. The arm and wrist material in particular indicated the concordance with the Flores type. This seems to add further weight to the assertion above that there is nothing here to suggest that Sawu specimens originate from a separate species.

Associated with the human bone specimens were some remnants of animal origin, notably identifiable remains of the stegadon, or prehistoric elephant, and the Comodo dragon. Both species seemed to have formed part of the prehistoric hominid’s diet, an observation that adds further weight to the concordance with Flores.

Concluding remarks

This preliminary paper is designed to set the parameters for the more detailed reporting that will follow. Thus far, analysis suggests that the hominid population of Sawu was at least related to that of Flores. It is likely that they were long-limbed, small-brained hominids about one metre tall. The development of their culture, as evidenced by their stone tool manufacture, was highly sophisticated, however, and like Flores man it shared features that were prevalent at the time in contemporary Homo sapiens. There is no evidence thus far that points to Sawu residents being a wholly different species. Indeed, given the existence of remains of a similar type in the Philippines, it is possible that this dwarf hominid was in fact widespread in the region, thus calling into question the need for a separate descriptor even for Flores.

Far from being a disappointment for the researcher, this finding is in fact quite radical and remarkable. Though Sawu is on the same side of the Wallace Line as Flores, there is a significant amount of ocean between them. Indeed, there is a substantial amount of ocean between Sawu and anywhere! If, as this preparatory paper suggests, the hominids of Sawu and Flores were of the same species, then there exist three possible explanations. One: the early hominid population occupied a single land mass that subsequently split apart or suffered inundation by rising sea levels. This process, however, would have taken place in geological time, and would probably have resulted in subsequent evolutionary changes in the separated populations, causing them to diverge more significantly than the archaeological evidence suggests. Two: the possibility remains that what we are finding are deformed or malformed Homo habilis individuals. The fact that the two island communities seem to have shared the same diet and lifestyle may have resulted in the same developmental problems. The lack, however, of a greater number of contemporary and indigent Homo habilis specimens interspersed with those of the ‘hobbit’ man would suggest that the latter’s small stature was a population trait and not a relative rarity within a larger and physically different population. Three: (and this is the really interesting proposition) the Sawu and Flores remains are of a single species and that separation by sea occurred in non-geological time, thus not allowing enough time for there to have been divergence by evolutionary mechanisms. Equally, and more probably, given that evidence from Flores points to the possibility that these hominids lived there within the last thirty thousand years, the possibility emerges that these pygmy ‘hobbits’ were in fact capable of ocean-going navigation and that their spread throughout the region was as a result of migration, rather than separate local evolution.

Readers of this preparatory paper will now understand why this theory needed to be aired and discussed so that subsequent publications can consider this as yet wholly theoretical, but revolutionary idea. Prehistoric hominids may have migrated.