Chapter 29
DENTITION
The work became tedious as no other significant finds were made, nothing that could resemble a stone tool or bones. The floor of wooden planks that had been installed over the excavation area had been divided into one metre squares delimited by strings and labels. The excavators sat or lay on the planks removing the overlay a couple centimetres at a time, progressing slowly by carefully scrapping away at the exposed surface.
Life in the camp fell into a routine with little distraction except for the same troop of monkeys that were getting used to the intrusion into their territory, watching from behind a curtain of leaves and branches, and from time to time daring to descend to the ground waving their small fists and shrieking in derision at workers efforts.
It was well into the third week when the dig had reached more than a metre deep into the floor reaching the bedrock in C5. It was a disappointment they had hoped for much deeper deposits containing possible evidence of a longer period of human presence in the cave. Since they could go no deeper they then started to excavate further back into the cave and to their general excitement as more traces of charcoal were uncovered at a level that was difficult to readily date due to the fact that little was been found other than a few bird bones. As they proceeded carefully more charcoal turned up and more samples were expedited to Jakarta for radiocarbon dating, carefully packed and sealed to avoid contamination.
In addition samples of quartz that had been collected in the sediments were sent to Jakarta, where they could be dated by another method called Optical Stimulated Luminescence or OSL, that could determine the time since the particles grains of quartz were exposed to sunlight. That would help to crosscheck the dates of the charcoal and the different levels in the sediments.
They hoped for first results the end of that week by the satellite phone, which would possibly confirm their estimation of the strategraphic dating essential for the continuation of the excavations. Their fear was that the cave would turn out to be a dead end and that borneensis man had been an isolated individual, who had died alone in the cave away from his family group.
Williams confirmed the skull found by Ennis was in a what appeared to be a recent slippage, where the sediment had been carried down towards the cave mouth in what had been an abrupt change due to flooding when the underground stream that drained the water seeping in from higher levels suddenly changing its course.
The trough that had been gouged in the cave floor by the stream in its new course had exposed a series of different sedimentary layers. Under the hard cover the most recent layer was a build up of guano covering three other older layers, dark brown, light-grey and a thin pale yellow band of silt like deposit covering the limestone bedrock. The total depth was no more than one hundred and fifty centimetres.
Where exactly in the cave system had the skull come from? Its light colour suggested that it had been in the younger layer and the shallowness of the sediment on the cave floor confirmed the recent dating of the skull.
As the afternoon storm clouds gathered up over the summit of the limestone cliffs they made a break and started to speculate on the dates, as they awaited more solid news from Jakarta. Williams explained that the stratification throughout the cave system was very similar and lower layers of light coloured soils were at the most a few thousand years old. The charcoal that had been found in the darker soil was indicative of human presence, and could be no older than the underlying layers, a point that would certainly limit the degree of error in the radiocarbon dating.
They dug and trowled further into the cave C5 extending the excavation work opening up new sections that were crisscrossed with strings and markers under the board walks. Each section was carefully identified and every single piece of stone was noted with the appropriate references to build up a picture of the cave’s history.
Deeper into the cave some small animal bones and small pottery shards were uncovered. The pottery was identified as late Neolithic by the experts. Gradually as the excavation data was accumulated and compared with the environmental reconstruction, sediment analysis, the examination of bones and artefacts, a picture of the cave’s history and occupation was slowly formed.
In the gloom of the dim lamps cast long shadows over the cave, and the silence was broken only by the scratching and scraping of trowels, and the grunts of the archaeologists, in the back ground was the echo of the small diesel generator that throbbed away supplying the light necessary to identify any objects of interest. The only other activity was reflected by the creaking of the boards as assistants carried away the buckets of the carefully removed debris to the sieving area outside.
A heavy atmosphere of delayed expectancy slowly seeped into the camp, it was not one of resignation, but after discovery of the premolar, to the general disappointment of the team, nothing else turned up. In addition the total silence from Jakarta dampened the enthusiasm of many of the younger team members.
‘Get me some better light,’ shouted Tegu.
Pierre Ros walked over with a powerful hand lamp.
‘There!’ Tegu said pointing carefully with the tip of his trowel. Sticking up from the sediments was something about the size of a thumb nail; it glistened from the thin film of condensation that clung to the small stones as they were uncovered.
‘What’s this?’
‘Another tooth by the looks of it.’
‘That’s what I thought, a molar.’
‘Lets get a camera here…and video cam.’
It was vital to record anything that could be of importance in a precise in situ location with its strategraphic sequence. Collin Williams arrived with the photographic material followed by Ennis carrying the video cam recorder.
‘Let’s get some better lighting in over here!’
‘Be careful, don’t let’s rush this.’
There was a sudden surge of enthusiasm as word of the find reached those outside. A wave of excitement flowed over the camp spreading out to all hands including the guards, cooks and Ibans porters.
‘What shall we do?’
‘Shall we wait for Aris and the others?’
‘No,’ said Ennis, ‘maybe it’s nothing. Don’t move it but try to uncover it, the material around it is fairly soft.’
Tegu left his place to Pierre Ros who got down onto his knees inspecting the tooth carefully. He then carefully started to uncover it with a small spatula. The surface of the tooth lay at a shallow angle; he worked slowly around it, then downwards uncovering the edge of what appeared to be a second molar.
‘Looks like part of a lower jaw,’ he said calmly lifting himself up with an effort. ‘What next?’
‘I’ve got that on the video cam, what about you Collin?’
‘Yeh, on film and on the digital camera.’
‘Let’s get it transferred onto a portable PC and we’ll have a look at it before we go any further.’
They cleared the cave of personnel and Pierre Ros instructed the guards not to let anybody into the cave until they returned. They then made their way down to the stepped path to the base camp and for once without complaining about the heat and distance. Shafts of sunlight seemed to brighten not only the forest but also their hopes, a change from the rain and dense low cloud that had set in over the last couple of days. Once in the main tent that served as their headquarters and work area Williams quickly downloaded his camera onto one of the portables and open the file containing the jpegs.
They zoomed in on the colour images taken from different angles showing what was clearly a molar.
‘Right, enlarge that one,’ said Ennis.
He zoomed it to 500%.
‘What do you think?’ he asked Ros. ‘Is it the same as the first one?’
‘I’m not sure about that, but it’s definitely the tooth of a hominid,” he said slowly, “though a strange one at that. It is a molar, but a little big, somewhat bulbous at the crown, you see these cusps here,’ he went on pointing at the screen imag
e with his ballpoint. ‘Very strange.’
‘Okay so it looks like it’s hominid, we’ll need to uncover more for confirmation,’ said Ennis business like, wanting to get back to the cave.
‘Is it erectus?’
‘That I don’t know, it’s like the other, not mineralised!’
‘What do you mean?’
‘It’s not that old.’
Once they returned to the cave Ros meticulously started to remove the earth away from the teeth with a fine dental pick as the others tensely waited to see what would be uncovered.
The gange removed was sieved through a very fine mesh to extract the slightest clue then all was sealed in plastic bags for laboratory analysis. The larger particles recovered on the sieve were separated into what could be minute fragments of bone or organic material.
All the earth that had been removed from that sector was isolated then carefully sieved, washed in a water bucket from which the skimmings were removed on filter paper. The objective was to search for preserved pollen or the remains of vegetable matter and any other material that could provide vital clues to the past occupation of the cave.
The next day the first small stone flakes were found in an adjoining area, evidence that the past inhabitants had been capable of producing stone tools. It was impossible to link the skull and the tools without further analysis in the laboratory since floor had been disturbed by water movements and what had been found could have been carried there from other levels.
Nevertheless they were excited since it was further concrete evidence of the recent presence of Neolithic man using stone tools in the rainforest, where there was an abundance of other materials that could have used such as wood and bamboo or animal bones and horns. It was perhaps a sign that cave had been used as a temporary camp, as there were many such caves in the region.
The best part of the day was needed to extract was clearly a fragment of a lower jaw bone, most of the time being taken up by long discussions on how it could be freed from the soil that had held it prisoner for so long.
Finally it was freed and they carefully took the fragment to the tent outside of the cave placing it on a table and a sheet of filter paper. They stared in wonder, examining it under the bare bulb that added light to that which filtered through the canvas roof of the tent. For many of them it was the first time they had been present at the excavation of what was such an important find. The only sound came from the heavy drops of rain that had started to fall and the monotonous sound of the small generator that throbbed away in the background.
The atmosphere was stifling as the usual late afternoon storm gathered, it was oppressive and the sweated trickled down their arms as they waited for Pierre Ros to utter some kind of momentous phrase that would be recorded for posterity by the scientific community.
‘It appears to be erectus,’ observed Pierre with some scientific reserve. He was cautious about the jaw fragment; he would need the opinion of Murtopo, who would not be back for another three days.
‘There’s little doubt that this did indeed belong to some kind of erectus, though we’ll have to wait for a definite prognostic.’
‘Is it from borneensis?’ asked Ennis.
‘Difficult to say….’
‘In any case the tooth is massive, compared to sapiens that is, very massive,’ said Soemarsono, Tegu’s colleague, an experienced palaeoanthropologist who had considerable experience with hominid fossils in East Java “Look here, you can see if they were modern human teeth they would be thinner. These are significantly bigger than ours.’
The daily routine on the site continued with renewed enthusiasm as they sifted through the cave’s floor for the remains of the man or men who had taken shelter there thousands of years ago. They progressed cleaning section by section whilst trying to build up a picture of the stratigraphy and events that had brought about the death of Borneensis.
A wet sieving station had been set up by the small torrent that cascade down from the rocks above. Assistants sifted the reject material from the dry sieves in the cascade, panning for anything that could resemble knapped stone flakes or bone fragments, animal or human.
The next afternoon two more teeth and several small bone fragments emerged from the cave. Pierre Ros kneeling on the boardwalk and the rough planks inspecting the excavation work allowed himself a broad smile of satisfaction. His experience in North Africa now coupled with Borneo was the culmination of his life’s work, few anthropologists were blessed with such two such discoveries in lands and times so far apart.
They had now several robust teeth, no doubt those missing from the upper jaw and more smaller facial and cranial fragments. What was equally exciting was the discovery of what appeared to be pieces of ochre that had been long used by man as body decoration.
The lower jaw parts and the teeth with the post cranial bone fragments found confirmed that Borneensis was a member of the species Homo erectus, with a cranial capacity of around 1300 cubic centimetres, very close to that of modern man, placing him in a parallel position on the evolutionary tree. Borneesis was probably a male whose age at death was calculated at being about twenty years old.
In another gallery of the cave several animal bones were uncovered and identified as pig and deer by Soemarsono, which seemed to confirm that the cave had probably been occasionally used as a hunting shelter by borneensis in his day to day search for food and a suitable place to sleep each night and shelter from predators. All signs seemed to indicate he was killed by a rock fall probably caused by torrential rains and flash flooding, never to return to his small family.
As time passed by the people of the Iban longhouse lost their initial interest and went about their daily work tending their vegetable gardens, or passed their time of day sitting and talking in the common area of the longhouse, as the women split rattan with pahangs into thin strips and others wove them into different kinds of sacks and baskets for their own use or for sale in the towns. Some of the men hunted in the forest for wild pig or deer, returning with the animals slung over their backs when they were successful.
The camp cook bought fresh fruit and vegetables from the Ibans, their gardens were productive, stretching up the hills, where they grew all kinds of tropical fruit, vegetables and rice. After the evening meal of nasi goreng and satay the expedition members sat inside, protected from the myriads of insects by the mosquito netting that draped down from the awning of the tents, watching smoke as it slowly lace its way up from the coils of mosquito repellent, and passed the evening drinking beer and speculating over their discoveries.
As usual Pierre sipped his tuak, he had obviously taken to the taste of the stuff, and as he relaxed he liked to recount his stories to all those who cared to listen.
‘The first serious anthropological work in Borneo was carried out by Harrison,’ he told his audience.
‘I’ve read about him in the guide books, a local hero!’ said Steve Smoult, the English satellite mapping expert, who had arrived that afternoon from Pontianak.
‘Yes, in Sarawak, here we’re in Indonesia!’
‘Just about!’ replied Steve sure of his knowledge as a mapping specialist.
‘Anyway, Harrisson was an explorer and adventurer. He led an Oxford University expedition in Sarawak to Mount Dulit and the Tinjar River in the thirties when he was only twenty years old.’”
‘A bit of a strange fellow, he even extended his anthropological studies to Stepney and Bolton to study the British working classes,” said Ennis who was familiar with Sarawak history. “He was also a specialist in jungle survival wasn’t he?’
‘That’s right, in WWII he joined the British Army where his knowledge of Borneo caught the attention of the Special Operations Executive and he was trained in commando and survival skills then parachuted into Sarawak to set up a guerrilla army of native irregulars to fight the Japanese. At the end of the war he decided to stay on Sarawak, and became Curator of the Sarawak Museum that he developed into a centre for social, a
rchaeological, and geographical research.’
‘So that’s how he got to making the excavations of the burial grounds in the Great Niah Caves,’ said Ennis.
‘Exactly, and he showed that the site had been occupied by humans for over 10,000 years. In 1958, he made the sensational discovery of a human skull, in the West Mouth of the caves, estimated to be over 40,000 years old. At that time he was ridiculed in scientific circles who considered the dating was complete fantasy.’
‘Like us today, but today everybody knows that Harrisson was right.’
‘Unluckily for him he didn’t live to see that, he was killed in a traffic accident in Bangkok back in 1976.’
‘It’s no wonder, if it’s anything like driving around these places it’s bloody dangerous and I know that from my experience over the last couple of days,’ Steve dryly commented having opted for the overland route from Pontianak to the camp site.
‘Well, he’s still a local hero and remembered for his work at the Sarawak Museum, Borneo’s leading museum with the most comprehensive data on the island’s natural history and ethnology.’
‘I suppose so, his wife was also well known for her work of reintroducing young orang-utans back into the wild.’
‘What interests us here is that those caves are the most important paleoanthropological site in Borneo, for the moment that is! Quite an amount of Neolithic stone implements and pottery have been found. More recent evidence shows continued human occupation of the Niah Caves until about two thousand years ago with cave paintings showing boats and human figures.’
‘What interests me is Santubong! The largest archaeological site in Malaysia, where thousands of ceramic shards were excavated there, dating to different periods but nothing of any commercial value.’
‘Always thinking in money,’ Pierre said mocking him.
‘Why not, if there was something of interest in the BC period in these parts it could be put on the market,’ chipped in Steve Smoult.
‘We say ‘BP’ Steve,’ said Pierre. ‘That’s - before present - it’s less confusing than saying BC. So 2000BC is 4000BP’
‘Yes I suppose that’s less confusing, geology is not really my thing, seen from space that is.’
‘It’s alright once you get used to and anyway BC doesn’t matter when you start to talk in tens or hundreds of thousands of years ago.’
‘I suppose BP doesn’t upset the non-Christians.’
‘Don’t want to do that do we,’ said Steve. ‘What about Jurassic then, that’s millions of years?’
‘That’s a little more complicated,’ said Pierre, ‘that’s part of what we call geological time scales. Right now, and for a long while to come we are in the Cenozoic era. There’s six era’s since the beginning of the planet. Each era is divided into periods...we’re in the Quaternary or fourth period if you care to know, and one million six hundred thousand years ago was end of the period before that, the Tertiary. Eras are divided into epochs, the current one is the Holocene, which started about 10,000 BP. Before that it was the Pleistocene that started about at the beginning of the quaternary.’
‘Hang on, I’m getting confused, maybe it’s the tuak,’ said Steve refilling his glass from a bottle that appeared to have seen a good few generations of the longhouse brew.
Pierre Ros laughed. ‘Don’t worry it’s all very arbitrary but you’ll get the hang of it.’
‘In the next era no doubt!’
‘What counts for us at this precise moment is the biologist’s and anthropologist’s time scale, the rest is much too distant and doesn’t concern man’s development, at least directly.’
‘It was the end of Miocene epoch when Hominoids appeared,’ said Ennis showing off his recently gained knowledge.
‘Hominoids, hominids?’ asked Steve.
‘Hominoids, that means man-like, it’s the super family that includes man and apes and from which our branch separated from a common ancestor six or seven million years ago. Hominids is the branch of the primate family to which we, present day man and our extinct predecessors, belong.’
‘Were they like us?’
‘Incredibly so and living a life not so very different to that of our fellow men in Indonesian Irian Jaya today.’
He gave a look of disbelief.
‘Yes, think about it for a moment…no think about it the next time you take a shit, then you’ll realise what kind of primeval animals we are.’
‘No need to be vulgar!’ he shrugged, ‘Anyway, your explanation is not very clear?’
‘Don’t worry, I haven’t finished yet, now we get to the stone ages, the first one is the Pleistocene epoch, which is divided into three periods, the upper, the middle and the lower Palaeolithic or Old Stone Age. Then there’s the Holocene epoch, that’s where we are now.’
‘That’s nice to know.’
‘It includes the Neolithic, or New Stone Age, and also the Copper, Bronze and Iron Ages. It’s also when agriculture started.’
‘Hang on what differentiates the stone ages?’
‘Good question, the Pliocene had only Oldowan stone tools or so-called Pebble Tools, the earliest known about 2 million years ago. Then came the Acheulian, which started about 1.5 million years ago when a sudden change took place with a more modern design and the appearance of bi-faced tools. After came the Clactonian and the Levalloisian.’
‘Now I’m really confused, where do all those names come from?’
‘The sites, you know…places where those tools were first found and recognised by prehistorians. For example Clacton in England.’
‘Ah! That explains a lot.’
‘There were others leading up to the Neolithic and modern man but I won’t confuse you any more.’
There is an ongoing struggle between scientists advocating different theories on the origin of modern man, often motivated by individual ambition and glory. Many paleoanthropologists in their quest to unravel human origins will seize at the least information, to prove or disprove a point, disputing dates, levels, bones and stones. Whilst in all professions there exists the usual mix of human weaknesses, including pride, arrogance and jealousy, it is curious to find this in the world of science dedicated to the search of truth, where many celebrated academics are known for their fits of characterial eccentricity and a general disdain for the discovery of others.
Such struggle surrounded anthropologists as they debated the geographical origins of modern man. There were those who advocated of the ‘Out of Africa’ hypothesis and those who supported the concept of ‘Multiregional’ evolution.
This second theory was based on the idea that man evolved in Africa some two million years ago then spread out into Europe and Asia, where he evolved forming the different modern populations that are however linked by interbreeding and cultural exchange. Considerable support existed in Asia for the Multiregional theory, especially from China where national pride and politics coveted the origins of modern man.
The Out of Africa theory is based on a much more recent African origin for modern humans, demonstrating that Homo sapiens evolved as a new species distinctly different from those that pre-existed it, Neanderthalians and Homo erectus, gradually replacing them. However, the Out of Africa theory was seriously questioned by its critics after molecular biologists had given credence to the theory with their analysis of mitochondrial DNA, which they declared, demonstrated that all present living persons could all be traced back to an African Eve, who had lived in Africa 200,000 years ago. The critics pointed to recently discovered early human fossils found in regions of the world outside of Africa that predated Eve contradicting their theory.
What exactly is mitochondrial DNA? It is the energy-producing organelles of the cells of which the DNA is transmitted uniquely by the mother. Since genetic mutations occur randomly and accumulate at a constant rate a molecular clock is created. This clock enables scientists to calculate the time back to a common ancestor of those humans living today and shows that a common mtDNA ancestor liv
ed about 200,000 years ago in Africa.
The ‘Out of Africa’ population was initially a population of just a few thousand individuals that grew and around 100,000 years ago started to migrate out of Africa, spreading to all continents gradually replacing all other existing species of man. The question remains as to whether this small number of individuals could have replaced the entire population of the world, composed of one or two million beings without interbreeding.
In Australia a series of fossiled skeletons were discovered at a place called Mungo, these were calculated to be about 60,000 years old that is when erectus was still very much alive in Java and other places in a more evolved form, sharing a number of common features with Mungo man.
It had been suggested that two different populations arrived in Australia from China and from Indonesia, and these had mixed to produce the ancestors of aboriginal population of present day Australia. The first arrival was erectus followed by Homo sapiens. Discoveries made in the south eastern region of Australia appeared to confirm the coexistence of two such distinct populations in prehistoric times. One having a gracile, or modern type of morphology whilst the other was of a more robust or archaic form with cranial features similar to those of erectus.
Professor Lundy had recognised that Borneensis could provide convincing evidence proving or disproving these theories. To do so further DNA samples were needed from scientifically excavated bones, avoiding all scientific controversy that could arise over suggestions of contamination of the DNA initially extracted from the calvarium Ennis had presented to him in Paris that spring.
For Lundy, Borneo was a remarkable laboratory since it had been protected until very recently times from the intrusion of modern man, the vast part of the island being pure virgin territory. In the less recent past in the early part of the nineteenth century the population of the island had been not much greater than a million. The main reason lay in the island’s geography. At that time the interior was covered by dense inaccessible rainforests and high mountain ranges whilst the coast region was protected by impenetrable mangroves. The forest dwellers had not the means to cut down two hundred year old hardwood trees, up to sixty metres high and two and a half metres in diameter, which explained to a certain degree why Borneo remained so under populated compared to its neighbouring islands such as Java, or the Malaysian Peninsula.
This remained unchanged for tens of thousands of years and over the countless generations of men that inhabited the island, living their nomadic or semi-nomadic lives in complete harmony with the never changing forest that provided their every need. Numerous cave and rock paintings in Niah and other caves across the island bore witness to their presence.
In modern times the population of Borneo was around fifteen million people, the majority living in Indonesian Kalimantan with a population density equivalent to a tenth of that of France. A large part of the present day population was the result of the Indonesian government’s policy of transmigration over the last fifty years, when entire villages were moved from the densely populated island of Java to take advantage of Borneo’s almost uninhabited forests and the boom in the forestry, oil and mining industries.
This resulted in grave problems for the indigenous populations whose ancestral lands of Borneo’s were forcibly taken by the logging companies and oil palm plantations.
‘Tell us about Mungo man, what link does he have with the discoveries here?’ Steve asked.
‘Well the theory is that both sapiens and erectus crossed to Australia within the same time frame, between 100,000 and 30,000 years ago,’ Pierre Ros replied with renewed interest.
‘Is it not logical,’ Ennis said, ‘to think that if they had lived side by side for about a hundred thousand years sapiens and erectus would have interbred?’
‘Well,’ Pierre said carefully, ‘they are considered to be distinct species, and there is little doubt that sapiens succeeded erectus. Whether they interbred is another question.’
‘How did they get to Australia? Was there a land bridge?’
‘No, there was never a land bridge from Indonesia, during the Quaternary that is the last 2.6 million years. On the other hand, New Guinea was joined to Australia by an overland route. The Wallace Line prevented man crossing to New Guinea or Australia by dry land, so they must have crossed by some kind of boat or raft! Two stretches of deep sea separate the Island of Flores from the rest of Indonesia. The first, between Bali and Lombok, is about twenty-five kilometres wide and the second, from Sumbawa to Flores, is nine kilometres wide. That means only animals that could swim or men with rafts or boats could have reached the remote island of Flores on the other side of the Wallace Line.’
‘How deep are the waters surrounding Flores?’
‘Deep…more than one hundred metres. The lowest level of the sea in this zone was somewhere between eighty and one hundred metres below the present day sea level, though some of these channels are much deeper.’
The Wallace Line, named after Alfred Russell Wallace, was the most important biogeographical frontier in Southeast Asia. The islands to the west were joined to the Asian mainland by land bridges when the sea level fell, and were populated by a full range of Asian land animals. On the other hand, the islands to the east, such as Flores and Timor, were separated by a deep sea barrier from the Asian continent and had few large land animals before the arrival of man.
There were other examples of sea crossing that seem to confirm the migration of early humans by some kind of raft or boat. For example the Straits of Gibraltar are thirteen kilometres wide, but when the sea levels were lower it was only five kilometres across and with some small islands in between and therefore much easier to cross.
Early man had lived in both Spain and North Africa, so he could have taken the long route through the Levant, or crossed by sea, whether he swam or floated across will probably never be known, but if he used some kind of a boat or navigable raft, as he seems to have done in Flores here in Indonesia, is another possibility.
The Flores evidence indicated that erectus seemed to have been a toolmaker and a boatmaker, and evidence in China indicated he was also able to make fire. It seems reasonable to imagine that he used materials such as wood and animal skins with which he could have made some kind of simple craft. In Germany, the 400,000-year-old wooden spears found in a mine, were perfectly shaped for throwing and balanced in the same as a modern javelin. These materials have not survived either because they were organic or not present in the same quantities as stone tools.
‘So the big question is when exactly did Homo erectus become extinct? Once our Borneensis find is published it will start a real brawl,’ said Ennis.
‘Well up until the discovery of Borneensis the site of Ngandong in Central Java has been the best clue, the dates there have supposed that his extinction took place between 53,000 to 27,000 BP. That means of course sapiens had also appeared on the scene.’
‘Was he responsible for the disappearance of erectus?’ asked Steve.
‘Probably, but that’s difficult to prove.’
‘What has Lombok got to do with erectus?’
‘Well some recent discoveries show the presence of erectus on the island of Flores, that’s to the east of Lombok by the way,’ said Pierre.
‘Lombok?’
‘In the Lesser Sunda island chain, off Java, and only a few hundred kilometres from the sites in Java, where erectus fossils have been found since the end of the nineteenth century.’
‘So he could have been capable of building a boat to get there!’
‘So it seems.’
‘Was Flores an island at that time?’
‘No, Flores was part of the prehistoric land mass of Sahul on the eastern side of the Wallace Line separated by 25 kilometres of deep and dangerous sea from Sundaland.’
‘Were the two landmasses ever joined?’
‘No, not at any time during the existence of man or his bipedal ancestors.’
There was a silence as t
hey tried to absorb Pierre’s explanations.
‘So this discovery points to early man’s capacity to build some kind of primitive sea going craft, about 800,000 years earlier than had been previously thought. This would mean that they navigated their craft probably using mountains and volcanoes as land marks as they sailed island-hopping from Java to Flores.’
‘So they then reached Australia overland?’
‘The fact that man was present on Flores means that he could have migrated into what is now Australia by foot when the land bridge was emerged or by sea when it was not. This of course conflicts with the idea that the first settlement of man in Australia dates back to 50,000 to 60,000 years ago, however the stone artefacts discovered in deep and easily datable volcanic ash deposits on Flores suggests it was much earlier.’
‘Is there any fossil evidence of that?’
‘No…but it does not mean that it does not exist, it simply hasn’t been found for the moment. You know people are very strange, they accept an idea until something turns up to contradict it, like a discovery, then everybody starts looking where they hadn’t thought to look before.’
‘Anyway it shows that erectus was capable of advanced communication and had developed manufacturing capacities that enabled him to build some kind of craft capable of navigating on the open sea.’
‘Absolutely. The evidence is there, in 1968 another Dutchman, a missionary and amateur archaeologist, who was living on Flores found some stone tools deeply embedded in deposits of volcanic ash. Then more recently excavations in a limestone cave at Liang Bua, in West Flores by an international team uncovered more evidence, stone tools to be exact, confirming that hominids had arrived on the island some 840,000 years ago.’
‘Confirming?’
‘That’s right, they used a technique what is called a fission-track dating proceedure on samples of volcanic tuff from the strata where the tools were embedded,’ explained Pierre Ros.
‘That’s some kind of lava?’
‘If you like, it’s another name for rock that was once loose pyroclastic material, in other words any ash, rock or cinders ejected into the atmosphere by volcanic eruption. Once it’s exposed to the elements it cements together forming a solid mass of rock that we call tuff.’
‘So how does this fission-track dating work?’
‘In very simple terms the volcanic ash contains different minerals including zircon, which is a perfect element for fission-track dating. Atoms of uranium-238 are found naturally in the zircon and with time they undergo spontaneous fission, meaning they break apart or explode, you know nuclear fission! This results in fragments that streak across the crystal lattice, a little like a meteor in the night sky, leaving tiny tracks behind them. These tracks are counted and the more there are, the greater the time since the rock crystallized.’
‘Incredible!’
‘Wonderful what science can do for us,’ said Pierre looking very pleased with the effect of his explanation.
“Maybe we could go to Liang Bua with Paul Suarez, he’s promised to take me to Komodo on his boat.
‘Why not, though we’d need more time. Liang Bua needs a few hours journey over fairly awful roads to the town of Ruteng, then a rough ride over a forest track to the cave.’
‘We’re used to that aren’t we?’