Britain's 'oldest' man.

The remains of Boxgrove Man were found in a quarry at Boxgrove, near Chichester, West Sussex, South England. He was first known from a shin bone, discovered in May 1994 after 10 years of excavation. Boxgrove Man is acclaimed as Britain's oldest man - and archaeologists are redoubling their efforts to find more of him. In 1995, English Heritage granted an additional 236,000 pounds sterling for the search, bringing their total investment in the project to over 1 million pounds - an event which has triggered much media interest. In 1995, there were excited reports of the finding of a human tooth at the site - followed by the discovery of a second tooth. Of course, no one argues seriously that these fragments all belong to the same individual, but it's a nice thought.

All the measurements taken from the shin bone are at or beyond the upper end of the range determined for modern man (these details are in Nature, 369, 311-313, 1994). Consequently, Boxgrove Man is reconstructed to be powerfully built individual over 6 feet tall. He is said to be a representative of Homo heidelbergensis. As far as life-style is concerned, the evidence suggests he was a hunter-gatherer: the site is rich in animal bones which are thought to have been slaughtered by man for food.

The first tooth, found on August 24th by a student archaeologist, has a buildup of tartar around its base and shows signs of root damage and periodontal disease. The inference is that severe toothache was a problem for the individual concerned.

Archaeologists are finding stone tools - but these flint bifaces are a focus of controversy. `The argument is that these things may not be human artifacts at all' says Dr Chris Stringer of the Natural History Museum. `If you look at enough pebbles, you'll see some that look as if they have been artificially shaped' (The Times, 21 June 95, page 16). However, other archaeologists conclude differently. In a news briefing entitled `smart tools', the New Scientist reported that the Boxgrove toolmakers `were better at making tools than they have been given credit for' (5 November 1994, page 11). An archaeological team at University College London have been making replicas of the tools and have worked out how the bifaces were prepared: initially shaping the stone with another and then refining the shape with an antler. Finally, a piece of a deer's long bone would be used to do finishing touches. The leader of the team, Mark Roberts, said that the tool-making process was evidence that Boxgrove Man and his contemporaries `were capable of planning and executing simple manufacturing processes.'

Controversy is strong on dating too - for some have suggested that Boxgrove Man is the oldest European. However, Chris Stringer points out that there are at least 10 sites in Europe claiming to be older. One of them is at Atapuerca, northern Spain. According to the reports, the dates at this site have been fixed by reference to the `vole clock'. People have examined the dental anatomy of water voles and they have changed with time. These trends, which some call `micro-evolution', are considered to occur almost simultaneously over a wide area, and in many of the sites where the dead voles are found, an archaeological date can be assigned. A pattern has emerged, whereby the vole clock has been calibrated by reference to other dating techniques - and it is now in routine use. `Short chronologists'remain sceptical about all these other European sites - and maintain that the Boxgrove Man date should be regarded as the oldest `convincing'date for a human in Europe.

Nevertheless, even the date of Boxgrove Man has been challenged. After discussing the `notorious' difficulties of dating the Middle Pleistocene of northwest Europe, Bowen and Sykes (Nature, 27/10/94, 751) present their own estimate based on the racemization dating method. Gastropods recovered from the Boxgrove site have yielded results which `are correlated with oxygen isotope stage 11 (423,000-362,000 years before present) and thus provide an approximate age of about 400,000 years for "Boxgrove Man" - an entire ice-age younger than the previous estimate'. However, after further discussion, they conclude `In our view, there are too many uncertainties in the various dating methods to be able to assign a definitive date for the occurrence of early hominids in the British Isles'.

Mark Roberts replied by pointing out that a variety of geochronometers have been used at Boxgrove. Thermoluminescence techniques gave dates of 175,000-230,000 years; electron-spin resonance gave 205,000-281,000 years; uranium series methods gave a lower limit of 350,000 years; aminostratigraphy with marine species gave 303,000-524,000 years and with terrestrial species the results were 303,000-339,000 years. `The fact is that the range of dates obtained was so varied that we used mammalian biostratigraphy, from a European database, to construct a more accurate and testable chronological model when combined with detailed lithostratigraphic data'.

Before leaving the issue of chronology, it is worth asking how it is possible to assess the accuracy of these various estimates of age. With some sites, only a few dating techniques are possible - and the dates are accepted as the best estimate. With Boxgrove, where many conflicting dates have been obtained, why is it that the higher figures obtained from the vole clock are given the greatest weight? Since the vole clock is calibrated by reference to European sites, can it be used with confidence in southern England? Are we so sure that these adaptive changes to dental anatomy occurred at the same time all over Europe?

Having said all this, what are we to make of the fossil bone and the two teeth? What is the significance of the find? How does it relate to another early Brit: Swanscombe Man? Since dating is not so well established as many people think, is it possible that these people were contemporaries? The Independent on Sunday (27 August 1995) referred to these early inhabitants of the Boxgrove area as `an extinct form of early man'and `the ancestor of Neanderthal Man'. There is a strong tendency to `fit' data into theoretical moulds, and where data is limited, the fitting process is relatively easy to do. However, it has little scientific merit. It would be more judicious to qualify carefully hypothetical genealogical relationships and to remind people that source data is scarce. Perhaps the best answer we can give to people is `Let's wait and see!' Feelings on many aspects of Boxgrove Man are running high! This is, after all, Britain's primary offering to the story of man's origin! There's enough here to keep speculation going for years! The writer of The Times article concluded: `Nobody knows if Boxgrove Man had a sense of humour, but if he did he would be enjoying the scrap.'

David J. Tyler (1995)