Monday, May 31, 2010

Godwin and the Fenland Research Committee (1932--1948)

The first successful use of pollen analysis to explore vegetation history was by the geologist Lennart von Post, in Sweden in the 1920s. By identifying the relative abundance of pollen grains of different trees and plants in different strata, the ecology of an area during prehistoric times, that is, its climate, forest composition, and agricultural practices, and any changes to these over time, could be elucidated. This new scientific technique spread rapidly throughout Europe, so that by 1927 more than 150 papers about its use and the mapping of prehistoric ecologies had been published. In 1923 Harry Godwin began to employ pollen analysis for archaeological ends in England. Godwin (1901--1985) studied botany and geology at Cambridge University where he worked for the whole of his career.

During the 1920s and 1930s researchers began working together using pollen analysis to discover and map the impact of climate and human activity on the history of woodland (tree and shrub) vegetation. Refinements in technique led to the identification of many different kinds of pollen, such as the pollen of herbs and weeds and cereals, many of which were important indicators of past human activity. These refinements permitted the interpretation of certain features seen in pollen diagrams from natural deposits as the faint traces of the activities of the first farmers of the Neolithic period. One such feature is elm decline, which appeared in pollen diagrams as a noticeable and widespread reduction in elm pollen at a particular point, and was used to divide the Atlantic pollen zone from the succeeding sub-boreal one. Was this elm decline the result of human activity or climatic change or both? Many pollen diagrams revealed changes just above or after the decline horizon, which probably represented prehistoric episodes of woodland clearance, farming, and abandonment.

As pollen analysis developed across Europe, and its results were compared and tabulated, so could diagrams of different pollen compositions be mapped and divided into zones representing different phases of time, thus providing a means of dating suitable sediments. Precise correlations could be made within climatic, geographic, faunal, botanical, and archaeological pollen and sediment sequences. This chronology was used for the next twenty years until the advent of radiocarbon dating in 1950. In September 1931, a fishing trawler dredged up a harpoon from the Lenan and Ower Bank in the North Sea. Godwin analyzed a sample taken from the North Sea bed and found it was boreal in age (that is, from before the sea-level changes after the last Ice Age). The harpoon was examined by members of the Prehistoric Society of East Anglia in 1932 and identified as an example of a finely barbed antler point, similar to those found at many Mesolithic Magelmosian sites across northern Europe and as far east as Estonia. What was even more interesting was that the sediment surrounding the harpoon was from fresh water. So this harpoon from under the sea was originally from a freshwater site, on hilly land that had been covered by the melting ice sheets at the end of the last Ice Age, when the Baltic and North seas had joined. What this proved was that the prehistory of Britain, prior to the end of the last Ice Age, was similar to that of northern Germany and Scandinavia, whereas its postglacial prehistory was unique. To further elucidate these thousand or so years of ecological changes and their impact on human populations and settlements, British archaeologists, following the example of their Scandinavian colleagues, began to work closely with paleobotanists, geologists, geographers, and biologists.

Godwin began to study the fens (or swamps) of East Anglia and Cambridgeshire with archaeologist Grahame Clark. The Fenland Basin of East Anglia was an ideal place to begin to study and map the history of British vegetation since the last Ice Age and to correlate this with geographic and demographic settlement changes at the same time. The area had been flooded by the North Sea and then covered by postglacial waterlogged deposits. During the sixteenth century AD the fens had been drained for agriculture, and by the twentieth century their upper peat beds had worn away in some places, so that banks of marine silt could be found. Air photographs (with O. G. S. Crawford) and ground surveys mapped the original fen waterways and the flat and built-up areas used for agriculture and settlements. In 1932, inspired by Godwin's expertise in pollen sampling and paleobotany and Clark's interest in using both for archaeological ends, the Fenland Research Committee (FRC) was established to conduct foundational research into the reconstruction of ancient British landscapes and environments. The FRC has been described as 'the first truly modern prehistoric project, because of its interdisciplinary scope.' At its peak, as Pamela Smith noted, it comprised forty-two specialists, including faunal, mollusk, and charcoal experts.

Godwin established the relationship between pollen zones and the stratigraphy of the peat by identifying the relative abundance of the pollen grains of different trees and plants in different strata. These analyses delineated the ecology of the area during prehistoric times, specifically its climate, forest composition, and agricultural practices. Godwin's pollen analyses of the peat deposits of these swamplands (or fens) elucidated the history of changes to their vegetation, and from these data Clark could interpret their impact on human occupants and geographic development. The FRC worked throughout the 1930s until 1948, when it became part of the subdepartment of Quaternary Studies at Cambridge University.

Clark and members of the FRC excavated and analyzed material from a number of different types of sites. At the site at Peacock\u2019s Farm Clark excavated flints from a Bronze Age level, and underneath that pottery from a Neolithic level, and below that a typical Tardenoisian core with other stone tool flakes and pieces from the Mesolithic period were found, the first time such a culture sequence had been demonstrated on a British site. The final report set the cultural remains in an environmental context. Other sites, such as Mildenhall Fen and a Bronze Age foundry, were explored for different reasons but in every case there was a conscious attempt to integrate archaeological and ecological information.

Other archaeologists at Cambridge, such as O. G. S. Crawford, Christopher Hawkes, and Stuart Piggott, all participated in the FRC's working committee. During the 1930s many undergraduates and postgraduates, such as Glyn Daniel, Thurstan Shaw, Charles McBurney, and J. Desmond Clark, had their first experience of fieldwork on FRC surveys and excavations. The FRC published five reports on archaeological excavations and thirteen studies of postglacial history by Godwin, in preparation for his classic History of British Flora.

Godwin became a global leader in ecological thought and practice. His work in the fenlands with Clark and other scientists, along with their data and interpretation, was finally published in 1950 in The History of British Flora. In 1948 he became the founding director of the subdepartment of Quaternary Studies. In this position and later, as professor of botany, he contributed to the uses of radiocarbon dating, to the geological history of changes in land sea levels, and to the archaeological implications of this work. Palynology and paleobotany have long since become essential to the reconstruction of past climates and ecologies and central to the business of archaeology. Godwin was knighted in 1970. Clark was to become Disney Professor of Archaeology in Cambridge and was knighted as well.

Further Reading Clark, J. G. D. 1989. Prehistory at Cambridge and beyond. Cambridge: Cambridge University Press. Fagan, B. 2001. Grahame Clark. An intellectual biography of an archaeologist. Boulder, CO: Westview. Smith, P. 1997. Grahame Clark's new archaeology: the Fenland Research Committee and Cambridge prehistory in the 1930s. Antiquity 71: 11--30.

Publication of The Mesolithic Age in Britain (1932) and The Mesolithic Settlement of Northern Europe (1936)

The picture, reconstructs a site near Broadway where young archaeologists found flint microliths (used about 8,000 years ago) It shows a mesolithic hunting group, who lived in the period just after the last Ice Age.

The last prehistoric period to be named and understood in any detail was that between the Paleolithic and Neolithic periods. In the early twentieth century it was designated the Mesolithic, literally 'the middle Stone Age.' Some of the reasons for this late identification and designation lie in the fact that its study fell between disciplines as well. At that time the Paleolithic period, from 30,000--10,000 BC, characterized by big-game hunters with large tools and cave paintings, was the province of geologists. The Neolithic period, from about 5000--2000 BC was the province of archaeologists. The 3,000 years of the Mesolithic were therefore a puzzle.

This time, ca. 9000--6000 BC, was thought to be a period of cultural regression because people had used simpler and smaller stone tools, or microliths, as distinct from the larger stone tools used during both the Paleolithic and Neolithic periods. So what was the Mesolithic? No great leaps forward in human culture seemed to be evident, and it was so insignificant that there was a debate about whether it was a period in its own right, or whether it should be called the epi-Paleolithic or the proto-Neolithic. During the late nineteenth century the great French archaeologist Gabriel de Mortillet claimed that Europe was unoccupied during the period between the cave painters and the crop planters--or him there was no Mesolithic. In the 1920s Gordon Childe dismissed it as making a negligible contribution to European culture.

In 1932, less than ten years after Childe's dismissive comments, English archaeologist Grahame Clark revolutionized our understanding of this period. The Mesolithic, Clark argued, was a time of major transformation in European prehistory. At its beginning humans were living as they had for the last 30,000 years, and at its conclusion they had adopted agricultural economies, had ranked societies, and had altered the natural environment to suit themselves. Clark believed the microliths they used were the basis of a versatile tool kit--a set of tools that could be adapted in a number of ways on a variety of resources--or arrows, spears, fish barbs, or as sickles for hunting and gathering. Instead of being evidence of forgetting how to make big tools, they were proof that big tools were no longer needed. Life in the Mesolithic required a whole range of smaller and composite tools, because people had diversified their food resources.

In his two books, The Mesolithic Age in Britain (1932) and The Mesolithic Settlement of Northern Europe: A Study of the Food-Gathering Peoples of Northern Europe during the Early Post-glacial Period (1936), Clark proved that the great changes in climate that had occurred during the Mesolithic period had an enormous impact on the environment in northern Europe and on the lives of the people who lived there. The effects of climate change included rising sea levels, which resulted in flooding of low coastal areas and the creation of new high coastlines, and global warming, which resulted in significant changes to vegetation and animal communities. Paleobotanic research and pollen analysis documented a radical change from open tundra to widespread forests by 8000 BC. The retreating Arctic ice cap caused the extinction of larger animals such as mammoths. Larger herbivores such as reindeer followed the ice cap north, while the smaller red deer adapted to the forest by living in smaller herds, and others, such as roe deer and wild boar, adapted by extending their ranges. There were a greater variety of smaller animals available for food, such as wildfowl, and there were more coastal resources, such as fish and shellfish. The humans who inhabited this warmer landscape made social, economic, and technological adaptations to survive.

Clark demonstrated that the archaeology of the Mesolithic provides evidence of a more intense exploitation of this new environment by hunter-gatherers. Smaller-scale resources, such as shellfish, nuts, and small birds, became important parts of the human diet, and they developed new hunting and harvesting strategies to maximize seasonal forest and marine resources and broadened the basis of their subsistence to include more species. Domesticated dogs appeared at around this time, probably as an aid to hunting and killing animals. These economic and technological developments during the Mesolithic period made a greater degree of sedentism possible. Humans reoccupied seasonal sites on lakeshores and seashores and in forests and at rock shelters in expectation of seasonal resources. At some point they may have stayed year-round in expectation of these resources and the need to defend them and their territory. Abundant and reliable food sources also meant a growth in population, economic success and wealth, and the development of trade networks. Clark was convinced that some of the characteristics of the Neolithic period originated during the Mesolithic.

Further Reading Clark, J. G. D. 1932. The Mesolithic Age in Britain. Cambridge: Cambridge University Press. Clark, J. G. D. 1936. The Mesolithic settlement of Northern Europe: A study of the food-gathering peoples of northern Europe during the early post-glacial period. Cambridge: Cambridge University Press. Fagan, B. 2001. Grahame Clark: An intellectual life of an archaeologist. Oxford: Westview. Rowley-Conwy, P. 1999. Sir Grahame Clark, 1907\u20131995. In Encyclopedia of archaeology: The great archaeologists, ed. T. Murray, 507\u2013529. Santa Barbara, CA: ABC-CLIO. Rowley-Conwy, P. 2001. European Mesolithic. In Encyclopedia of archaeology: History and discoveries, ed. T. Murray, 478\u2013491. Santa Barbara, CA: ABC-CLIO.

Sunday, May 23, 2010

Establishing Dendrochronology (1929)

The growth rings of an unknown tree species, at Bristol Zoo, England.
Andrew Ellicott Douglass (1867–1962) had a long and eminent career in astronomy, helping to establish and operate three major astronomical observatories—the Harvard College Observatory at Arequipa, Peru; the Lowell Observatory in Flagstaff, Arizona; and the Steward Observatory at the University of Arizona in Tucson—before he became involved in archaeology. And who would have thought that such an esoteric subject as astronomy could provide the dirt discipline of archaeology, at the other end of the scientific spectrum, with a scientific dating system that would change the writing of prehistory and history itself?

In the 1920s Douglass’s interest in the effect of sunspots on the earth’s weather led him to investigate the annual growth layers of Arizona pine trees to ascertain if there were any variations in tree-ring width. He discovered a relationship between rainfall and tree growth, and between cyclical variations in tree growth and sunspot cycles. Looking for extensive tree-ring records to help to substantiate his theories, Douglass asked archaeologists in Tucson for pieces of wood from the ruins of a Southwestern pueblo. Within a decade Douglass was able to date some of these wooden remains back to AD 100 and others to AD 700.

For the first time in the development of archaeology, here was a scientific way of determining the date of wooden material from sites, and therefore of the sites themselves. In achieving this, Douglass created a chronology that was independent of other chronologies devised from ceramics, stratigraphy, and of course, the written record.

Douglass went on to develop the study of tree rings into the science of dendrochronology or tree-ring dating. This type of dating made substantial contributions to archaeology in the Arctic, Britain, central Europe, and the Mediterranean Basin. Douglass also provided dendroclimatic and dendroenvironmental reconstructions for archaeology. He retired from astronomy to found and direct the Laboratory of Tree-Ring Research at the University of Arizona, which he helped to establish as the preeminent center for dendrochronological research.

Further Reading Douglass, A. E. 1946. Precision of ring dating in tree-ring chronologies. Tucson: University of Arizona. McGraw, D. J. 2001. Andrew Ellicott Douglass and the role of the giant sequoia in the development of dendrochronology. Lewiston, NY: Edwin Mellen Press. Nash, S. E. 1999. Time, trees, and prehistory: Tree-ring dating and the development of North American archaeology, 1914–1950. Salt Lake City: University of Utah Press.

Publication of Air Survey and Archaeology (1924)

Bradbury Rings, Dorset, seen from the air, from O.G.S. Crawford and Alexander Keiller, Wessex from the Air (1928).

O. G. S. Crawford (1886–1957) combined his degree in geography with his experience as an observer in the Royal Flying Corps during World War I to pioneer the use of aerial surveying in archaeology.

In 1920 Crawford was appointed the British Ordnance Survey’s first archaeological officer. Since the early nineteenth century when the survey had begun mapping Britain, it had recorded all of the monuments and earthworks that were visible from the ground. Crawford provided a different perspective. He began by locating archaeological features on military aerial photos, then he consulted the records of other institutions, and finally he undertook new field surveys mapping the traces of earthworks in the English landscape that were only visible from the air and recorded on photographs. In this way archaeological evidence—prehistoric, such as Celtic field systems; historic, such as Roman military camps; and even medieval and more recent disturbances to the earth—could be located, researched, and recorded. These traces of the past were sometimes in great danger of disappearing because up until this point they were “invisible.” Crawford’s aerial surveys and mapping ensured that they would survive and be recorded and protected.

Crawford’s first book, Man and His Past (1921), described as a “topographical landscape history,” established the new subfield of landscape archaeology. In the book Crawford classified human settlements according to their function and position in a structured landscape and provided them with a chronological framework. Crawford went on to demonstrate how effective the relationship was between aerial photography and archaeology, publishing Air Survey and Archaeology in 1924 and Photography for Archaeologists in 1929. He also surveyed for and drew up a remarkable series of period maps such as Roman Britain (1924) and Britain in the Dark Ages (1935).

Thanks to Crawford, mapping a site from the air became a standard tool of archaeological survey, and over the next few decades it was used to great effect all over the world. Aurel Stein flew over Iran with the Royal Air Force to map the Roman limes, and Sylvanus Morley hired a plane and a pilot in Guatemala to enable him to find Mayan ruins in the jungle. In the late twentieth century, computer and satellite-generated geographic information systems (GIS) mapping provided archaeologists with an even more accurate tool in locating and describing features in cultural and natural landscapes.

Further Reading Chippindale, C. 2001. O.G.S. Crawford, 1886–1957. In Encyclopedia of archaeology: History and discoveries, ed. T. Murray, 384–386. Santa Barbara, CA: ABC-CLIO. Crawford, O. G. S. 1924. Air Survey and Archaeology. Southampton: Printed for H.M. Stationery Office at the Ordnance Survey. Crawford, O. G. S. 1955. Said and done: The autobiography of an archaeologist. London: Phoenix House.

Archaeology and reconstructing ancient warfare II


Cohort strength report on a writing tablet from Vindolanda (c. ad 100, north Britain).

The case of Julius Caesar’s attack on Alesia in 52 bc demonstrates the potential of archaeology at an abandoned site as well as various complications. Caesar himself provided a detailed account, including the complex siege-works around the hilltop (B Gall. 7.68–89), but there are sufficient imprecisions in the text to permit different identifications of the location. Partly because the site was of great symbolic significance for Gallic national identity, there was fierce provincial rivalry to claim it between Alesia in Burgundy and Alaisa in Comté. Napoleon III patronized excavations at Alesia, and even visited the site on 19 June 1861 to tour the trenches and listen to a translation of Caesar’s narrative on the summit; finance was available, but there was also strong imperial interest in results so that the integrity of the investigation might be challenged. Many found the results conclusive and a statue of Vercingetorix was erected as a memorial to a unified Gaul, but there was still sufficient argument between Burgundy and Comt´e to thwart a national bimillenary celebration in 1949.

Subsequent archaeological work has confirmed beyond doubt that Napoleon’s investigators were right, but also revealed how their reconstructions had been shaped by Caesar’s descriptions (B Gall. 7.72–4), which in fact contained certain inaccuracies: the location given by Caesar for some of the outer obstacles proved to be wrong, and, although the various items recorded by Caesar did exist, their disposition varied around the circumvallation. Caesar produced a homogenized description which embraced what might be found at certain points on the circumference but did not correspond precisely to any of the areas investigated. The constraints of memory, or perhaps the demands for literary clarity affected the written record, but the text then influenced the interpretation of the material remains for over a century.

Archaeological discoveries provide our main insight into the routine of military service, camp life with patrols, and the occasional skirmish which would be too minor to attract the notice of an ancient author. The writing tablets from Vindolanda, the archive of Abbinaeus, and the papyrus records of the camel corps at Nessana reveal the realities of the Roman army’s presence in different provinces at different times, the economic importance and social connections of the army in terms of supplies, local patronage, ownership of property, delivery of justice, and maintenance of order. Even on active campaign there was considerable tedium: the story of Socrates’ protracted immobility at the siege of Potidaea is preserved to show his devotion to knowledge (Pl. Symp. 220), but the interest which his odd behaviour generated among fellow besiegers also points to the boredom of a protracted blockade. Camp life required its diversions, as the antics of young Athenians on garrison duty illustrate (Dem. 54.3–4): we know about them because the victim went to court and employed a famous speech-writer, but otherwise such behaviour would pass unrecorded. Even here there is no escape from literary texts.

Archaeology and reconstructing ancient warfare I


Olympias, the modern reconstruction of a Greek trireme, was designed on the basis of a few and partial depictions of ancient ships, coupled with intelligent speculation.

Archaeology might seem to offer a better escape from the dominance of literature, and in certain areas it has produced useful insights. Without archaeological recovery of artifacts the study of ancient weapons would be dependent upon literary descriptions and artistic representations; survival of actual equipment gives a better idea of how material developed over time, even though there is still disagreement about how specific items, for example the Macedonian sarissa, might have been used. Analysis of fortifications may reveal aspects of the defence of a particular region, for example Attica in the fourth century, which do not receive comment in the surviving literary evidence, or permit the construction of overarching hypotheses about defensive strategies, for example how Roman imperial planning evolved in the first four centuries ad. On the other hand archaeological evidence is not neutral, and scholarly intrepretations are likely to be contested. A wide-ranging critique of Procopius’ panegyrical account of Justinian’s defensive constructions foundered because the material evidence was not presented fairly; although Procopius undoubtedly magnified Justinian’s actions and allocated him credit which belonged to others, his information did have some basis in fact. Our understanding of Roman attempts to conquer Scotland is largely informed by the physical remains of defensive walls, major bases such as Inchtuthil and Ardoch, and the numerous marching camps, since Tacitus’ account of his father-in-law Agricola’s actions only covers a small part of the struggle and had a strong personal interest. The material evidence points to the implementation of different strategies at different times, close supervision of the Highland Line in the late first century whereas in the early third century a widespread protectorate over southern Scotland and thorough ravaging and even deliberate depopulation of areas beyond may have been practised; but different interpretations are possible, however, and the chronology of sites can be disputed, especially where aerial survey has not been backed up by excavation.

There are limitations to what archaeology can provide. Naval battles cannot be elucidated by underwater archaeology, which has done much to improve other aspects of our understanding of ancient seafaring. The trireme, the main element of most battles, was a fragile craft but was unlikely to sink completely since it relied on its crew’s weight as ballast: boats would be overwhelmed in storms, wrecked on shore, or incapacitated in battle, but they would not end up on the sea bed to be preserved in silt for modern discovery. Olympias, the modern reconstruction of a Greek trireme, was designed on the basis of a few and partial depictions of ancient ships, coupled with intelligent speculation. The results of the investigation have enhanced our understanding of triremes, the prime importance of training, the factors affecting performance, and their susceptibility to poor weather, but the exercise might not have been initiated if there had been sufficient archaeological evidence to establish the ship’s appearance in the first place. Reconstructions have also been used to demonstrate the operation and effectiveness of ancient artillery, a process which has combined the information of ancient technical treatises, narratives of sieges and common sense.

Battlefield archaeology has been of minor help. Part of the problem is that many engagements cannot be placed with sufficient precision for detailed investigation to be undertaken: this applies to such major battles as Ipsus, Raphia, Magnesia, Mursa, Adrianople, whose general locations are known; some such as Mons Graupius float across a range of possible sites. At others, topographical change has affected the landscape to varying degrees: at Thermopylae the combination of centuries of silting and a rise in sea levels makes it impossible to dig down to fifth-century levels, at least without expensive pumping. Granted that most battles occurred at points along major communication routes, it is not uncommon for more than one engagement to have been fought at a particular site in antiquity (e.g. Chaeronea, Thermopylae, Mantinea) as well as more recently, with consequent complications for any investigation. Further, it is likely that many battlefields were quite effectively cleared: pillaging by the victors and subsequent scavenging by camp-followers and others in the vicinity removed most valuable or reusable items, corpses were usually collected for burial, not necessarily at or near the actual battlefield, and temporary constructions associated with an engagement, for example a palisade or ditch, might disappear quickly. The experience of the embassy on which Priscus served in 449, where they found outside Naissus that the whole area towards the river banks was covered with the bones of those killed in the fighting (Priscus fr. 11.1.54–5) was probably abnormal: there had not yet been the opportunity to bury the dead, or the people interested in doing so, though if one pressed Priscus’ words it would seem that the bodies had been efficiently ransacked.

One exception, however, is the Varian disaster of ad 9 in the Teutoburger Forest. The site was not precisely known: the narratives in Cassius Dio (56.20–2) and Tacitus (Ann. 1.61–2) left open several possibilities, and even if the regular discovery of gold and silver coins pointed to a location near Osnabrück other places were still canvassed. A combination of survey and limited excavation confirmed a site on the Kalkreiser-Niewedder depression, and clarified the progress of an engagement which was poorly known from the literary sources: the scatter of finds indicated where the main fighting occurred as the army struggled to continue its march until it became divided and units attempted to save themselves. The battlefield had been thoroughly plundered, so significant remains were only discovered in the burial pits dug by Germanicus’ army in ad 15 and near the Germans’ temporary turf walls, which had already begun to collapse during the battle as the desperate Romans attempted to escape. The bones showed signs of a period of exposure. The small finds reflected the diverse personnel of a large expeditionary force, not only fighting units but varied craftsmen, surveyors, clerks and medical personnel.

This site survived reasonably well since the battle was fought in a sparsely populated area on marginal land where the prevailing agricultural practice for most of the next two millennia consisted of dumping increasing quantities of organic material to improve the poor soil: ancient levels were preserved from interference, even if the conditions were not good for preserving organic remains. Another positive factor was that the fighting had some affinities with a siege, since the Germans used barricades to hem the Romans in. Sieges are slightly more likely than battles to produce archaeological evidence, since at least the location of the engagement can usually be identified. The evidence for many sieges was probably cleared quickly, since defenders would not want other attackers to exploit offensive works, whether the fortification was captured (e.g. Amida: captured by Persians in ad 502/3, Roman counter-siege 503/4) or resisted attack (Edessa in 544). But, where a site remained deserted after a successful siege, or only partially occupied, the remains might be considerable. At Old Paphos on Cyprus (498 bc) and Dura-Europus (c. ad 257) the remains of the Persian siege-works include ramps and tunnels, including at Dura the Roman counter-tunnels which contained the corpses of those killed in fierce fighting underground. At Masada (ad 70–3) the enormous scale of a Roman siege is revealed through the circumvallation with its associated forts and the siege mound up to the hilltop fortress.