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.
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