ARCHAEOLOGY: Boxgrove Man reveals his Stone Age-old secrets

Archaeologists plan to reconstruct the diet, lifestyle, medical history and even age at death of the Stone Age man whose half- million-year-old leg bone was recently found in a gravel pit at Boxgrove in Sussex.

Detailed forensic examination of the bone - the discovery of which was announced last month - is likely to reveal huge amounts of information about Western Europe's first human inhabitants.

What is more, in-depth study of prehistoric tools and animal bones found near by should help complete the picture. The bone itself is likely to reveal seven specific pieces of information.

Chemical analysis of a tiny fragment of the bone will give a clue as to Boxgrove Man's diet by revealing the relative frequency of various carbon and other isotopes. Different types of food leave different isotopic traces in bone - and scientists should be able to determine the rough balance of meat, fish and plant food eaten by the bone's original 'owner'.

Further analysis of the bone should reveal how old Boxgrove Man was when he died. The basic structural units of bone, multi- branched cylindrical objects called osteones, regenerate themselves throughout a person's life, leaving traces of previous osteones in place - a sort of lifelong super-clock.

Luckily the Boxgrove bone is broken - so scientists will be able to study its cross-section with relative ease. The unusually thick bone wall (the bone material between the bone's central 'void' and its outer face) suggests that Boxgrove Man had a physique somewhere between a light-heavyweight boxing champion and a rugby half-back. Much of the bone thickness would have been built up over the years in direct response to extremely regular bio- mechanical stress. This would have taken three forms - compression (sheer physical pressure on the bone), tension (usually due to extremely rapid changes of movement) and fatigue (due to very frequent intense activity).

Detailed measurements, calculations and comparative studies (plus X-ray and CT scans of the bone's osteone orientation) may yield clues as to just what Boxgrove Man was doing with his undoubted physical strength. The compression and tension needed to build up bone thickness to Boxgrove Man levels suggests the possibility that he was having to catch and wrestle with animal prey on a regular basis in order to get enough food to survive.

Studying CT (computerised tomography) scans of the bone may also reveal details of Boxgrove Man's life history. As bone grows over the years, illness or lack of food sometimes leave tell-tale marks in the bone's structure.

The bone may also yield vital details as to Boxgrove Man's precise relationship to ourselves. Scientists have so far failed to isolate DNA material from a human being of this antiquity, but attempts may be made with Boxgrove Man. Shortly after the bone was discovered - but before it was fully removed from the ground - several tiny fragments were removed and kept free from modern human and other contamination. This untouched material could eventually be used in an attempt to obtain half-million-year-old human DNA. If the scientists pull it off, they will be able to fit Boxgrove Man into the human family tree. He is unlikely to be our direct ancestor - more a cousin descended from a common African antecedent, perhaps 100,000 years or more earlier. He may, however, be a distant ancestor of Neanderthal Man.

The size of the Boxgrove bone shows that its original 'owner' was around 6ft tall (probably somewhere between 5ft 10in and 6ft 3in) - and this in turn suggests that his ancestors had arrived not that long before from a tropical grassland environment. Tallness in humans originated as an evolutionary adaption to enable our highly heat-sensitive brain to be kept well above the layer of very hot air found immediately above the ground in such environments. Nowhere else in Europe are there any known human remains or artefacts generally accepted as pre- dating Boxgrove Man. However, there is evidence of human occupation of Europe at another 12 European locations at around half a million years ago - the Boxgrove era. The tallness of Boxgrove Man and the apparent sudden arrival of humans in Europe at that period combine to suggest that the Boxgrove individual's ancestors had left the grasslands of tropical Africa no more than a few hundred generations earlier.

Lastly, a special dating operation on the bone would confirm its age. Up till now the bone has been dated by examining the geological strata it was found in and by looking at all the other more easily dateable material discovered in the same strata. However, if the bone (or any animal bone in the strata) is placed inside a gamma ray counter for several months, the counter would tot up the number of gamma particles being emitted quite naturally by the bone - and this would show its age up to a limit of 400,000 years. Given that the geological and other evidence all point to 500,000 years, a 400,000 reading would indicate the probable accuracy of the current geology-derived date.

The excavation of Boxgrove and the subsequent research - all funded by English Heritage - is being carried out by a team of scientists led by Mark Roberts, an archaeologist from University College London's Institute of Archaeology, assisted by Simon Parfitt and Dr Chris Stringer of the Natural History Museum.

In addition to information from the bone itself, archaeologists will be able to glean equally important details from other finds being unearthed within a few hundred metres of the bone. Excavations carried out at Boxgrove over the past 10 years have yielded hundreds of tools used by Boxgrove Man and his friends and relatives. They include hundreds of flint hand axes and knives, seven hammers, and the oldest non-stone tools found anywhere outside southern Africa - three bone hammers.

Not only have the archaeologists found the stone and bone tools themselves, but they have also discovered the sites where the Boxgrove People made them. At one place the toolmaking debris was preserved so well that one could actually see how the person was sitting when he made his flint tool half a million years ago. As he worked away, the tiny fragments of flint which showered down left an outline of the upper parts of his legs. Re-assembly of the thousands of fragments has recreated the original lump of flint from which the tool was made. Examination of this reassembled material has allowed them to discover just what that Boxgrove individual was making, legs outstretched, 500,000 years ago. It seems he was making a hand axe - probably to cut meat with.

Meat appears to have been an important part of the Boxgrove People's diet. Flint tool butchery marks have been found on the bones of four red deer, four rhino, one bear, one giant deer and one horse, several near to the edge of what was once a shallow pond at the foot of a massive 150-metre high chalk cliff.

It was at the edge of this now long-vanished stretch of water that Boxgrove Man seems to have met his death, and archaeologists will now attempt to solve one of the site's most tantalising riddles - just how did Boxgrove Man die. The only part of him unearthed so far, his lower leg bone, has animal teeth marks and what look like flint tool butchery marks on it.

The gnaw marks were almost certainly made by a wolf-sized carnivore - but finding out whether the other marks were really made by other humans will have to wait until a full scanning electron microscope examination of the marks has been carried out.

It could be that the marks were made naturally by sharp stones rubbing against the bone over the millennia. Or perhaps Boxgrove Man ended up as his next-door neighbour's dinner - with his bones being left to excite the taste- buds of the local wolves.

(Photograph omitted)