Environmental Archaeology. The journal of human palaeoecology

Volume 9, Number 2, Published October 2004

Introduction

Islands were the subject of the first AEA symposium held in 1981. The conference focussed specifically on ‘Environmental Aspects of Coasts and Islands’ (Brothwell and Dimbleby 1981). Some twenty years on, given the considerable developments within environmental archaeology, it was decided to revisit the theme of island archaeology and palaeoecology. The 2003 Annual Symposium of the Association for Environmental Archaeology entitled ‘Worlds Apart? Human Settlement and Biota of Islands’ included a wide interpretation of islands and island-related themes – offshore islands, islands in lakes and sea loughs, bog islands, artificial islands, social islands, island resources, island biogeography and island catastrophes. The meeting was held on the 24th – 26th April 2003 in Queen’s University Belfast and was attended by some 80 delegates including palaeoecologists, environmental archaeologists, archaeologists, human geographers and biologists from across Europe, America and Australia.

This volume brings together a selection of the papers arising from the meeting. Here, some of the recurrent themes addressed in this contribution are examined.

Discussion

Within this volume there are two papers, those by R. J. (Sam) Berry and Stephen Royle, that are perhaps unusual within the context of the environmental archaeological literature. Both, however, have an important contribution to make towards our understanding of island floras and faunas and highlight some of the issues which practitioners may need to consider. Both authors comment on the importance of islands as ‘laboratories’ for studying the effects of isolation on evolution. Berry draws attention to limitations associated with MacArthur and Wilson’s (1967) Theory of Island Biogeography, which failed to consider such effects upon the development and possible evolution of subsequent populations. Drawing upon the example of the British field mouse and three species which are characteristic of several British islands (the St Kilda mouse, Shetland mouse and Hebridean mouse), Berry argues that their speciation may be explained by colonisation from Viking ships and sequential introduction to other islands, each introduction having a potentially different ‘founder effect’, thus creating the range of different species and sub-species seen today in these islands. This suggests that sub-speciation and speciation may occur extremely rapidly in these island situations, in some cases in as little as a few hundred years. The genetic make-up of founder populations and the isolation of populations in island settings have played a central role in the study of evolution and explain why islands have held the attention of scientists ever since the publication of Darwin’s The Origin of Species (1859) and Wallace’s Island Life (1880). Environmental archaeologists and palaeoecologists need to be mindful that island floras and faunas may include rather different species and sub-species than might be expected from ‘mainland’ contexts. Additionally, the research suggests that environmental assemblages from island situations have the potential to identify speciation and sub-speciation in assemblages and contribute towards debates concerning evolution (cf. Bennett 1997). This issue was recently the subject of a Royal Society of London meeting in May 2003 (Bennett 2004).

Several papers touch on the role islands can play in helping to distinguish the influence of past human activity on natural ecosystems, a relationship that can be more ambiguous in mainland settings. For example, Derek Yalden and Robert Carthy indicate the negative impact that deforestation has made on woodland avifauna in Ireland. They discuss the importance of archaeological avifaunal data for enabling the discrimination between species that never arrived on islands, species that were once present but later became extinct and those that arrived late as a consequence of human introduction or modification to the island environment. Furthermore, the introduction of new species to an island, whether accidental or deliberate, can have devastating repercussions on the natural environment, as discussed by Royle regarding Ascension Island. In such instances, it is precisely the isolation of the islands that compounds the detrimental effects of human interference. The story of human interference on Ascension Island serves to demonstrate the extent of ecological change which can result when humans arrive in remote environments.

Island isolation can also lead to innovation, however, on the part of humans. Everett Bassett’s work on Tasmania would tend to suggest that humans can adapt in somewhat unexpected ways. It has generally been accepted that prehistoric Tasmanians somehow lost the ability to fish, resulting in the viewpoint that small populations can become both intellectually and culturally disadvantaged as a consequence of isolation and population size. Bassett argues that this assumption is unfounded and is based on inadequate faunal evidence and preconceived ideas concerning the value of fishing and the nature of fish remains recovered from archaeological contexts. Environmental archaeologists, therefore, need to be cautious in the interpretation of remains from isolated populations; the application of mainland theories need not necessarily have a major relevance to the study of island archaeology.

Islands have the potential to provide a diverse range of resources – terrestrial and non-terrestrial – but we should not make assumptions about the importance of these resources to human populations. A number of papers highlight that the availability of resources need not have been the main reason for the exploitation of islands, and cultural considerations may have played a more significant role. Rachel Ballantyne examines the question of why the Early Medieval rural settlement at Ely, East Anglia, England, appears to have under-utilised the local fen resources, in favour of those from farming. She suggests that the rich economic resources of the fen were not recognised by the monastic house.

Drawing upon bone isotope and archaeozoological evidence, Rick Schulting, Anne Tresset and Catherine Dupont demonstrate that during the Mesolithic period along the Atlantic façade diets appear to consist of largely marine foods. During the Neolithic this component had declined to be a minor contribution to the diet, with terrestrial resources contributing a large proportion of the diet. However, the activity on islands appears to begin in the Neolithic – Mesolithic exploitation, where it happened, was much more ephemeral. In contrast, in the Channel Islands, David Bukach suggests that there is sufficient evidence to warrant the consideration of a Mesolithic presence on the islands immediately prior to the arrival of farmers in the Early Neolithic. The evidence hints at a period of interaction between the Mesolithic islanders and the mainland farmers prior to the full ‘neolithisation’ of the island. On this basis, Bukach proposes a two-stage model to describe the transition. In his model, the island’s biogeography – specifically its remoteness and its finite resources – plays a central role in determining the ultimate adoption of a Neolithic way of life.

The presence of a body of water around a landmass – the typical perception of an island – does not imply isolation, a point illustrated by several authors in this volume. Islands of different forms become increasingly important as locations of settlement during the Early Medieval period among the islands of the Atlantic façade. Using both textual sources and archaeological evidence, Christina Fredengren, Meriel McClatchie and Ingelise Stuijts investigate a number of social and agricultural issues concerning Early Medieval crannogs in Ireland. They challenge the preconceived notion that such sites were solely high-status settlements, and suggest that they were also used by those with less access to material wealth. In addition, they stress that despite their physical detachment from dryland, the everyday lives of the crannog dwellers would have necessitated a connection with dryland activities. In a similar vein, Emily Murray, Finbar McCormick and Gill Plunkett show that this situation equally applies to island monasteries off the coasts of Ireland and Scotland. In these contexts, water can also be used as an avenue rather than a barrier for communications (cf. Terrell 1997).

The effects of island living on the burial practices and health of human populations has received little attention, an exception being the work of Mulville et al. (2003) at Cladh Hallan, South Uist, Western Isles. As further evidence comes to light it will potentially be possible to compare and contrast the burial records of island and mainland populations. To go someway towards this Eileen Murphy, Richard Gregory and Derek Simpson provide an overview of post-Beaker through to Later Iron Age funerary remains discovered at Northton, Harris, Western Isles.

The effects of island biogeography can have impacts in areas which are beyond physical islands in the strictest sense, such as the dry ‘islands’ in wetland landscapes described by Ballantyne. Taking an even broader view, one can also examine vegetation ‘islands’ in woodland systems. The paper by Nicki Whitehouse and David Smith explores the importance of ‘islands’ of vegetation within early Holocene woodlands and their implications for our understanding of the structure of Holocene forests. They discuss the range of natural processes, including grazing and forest fires, that may have played important ecological roles in creating open vegetation ‘islands’ within these systems. Importantly, they stress that ‘disturbances’ in the palaeoecological record can too readily be interpreted as the result of anthropogenic interactions rather than natural ecological processes.

Conclusion

The papers in this volume provide merely a sample of many diverse issues relevant to environmental archaeology and islands, and touched upon during the course of the conference. It is evident that islands present opportunities to approach a range of archaeological questions from a special perspective, the ‘island-as-laboratory’ notion being every bit as relevant to environmental archaeology as to the biological sciences. On a wider scale, it is interesting to note that the ‘island’ theme in archaeology is pertinent across a range of sub-disciplines. For example, a recent publication focussed on world islands in prehistory (Waldron and Enseyat 2003), while a session devoted to islands entitled ‘Island Metaphors and Island Myths’ was held at the Theoretical Archaeology Group’s annual conference in December 2003 at the University of Wales, Lampeter. A major international conference entitled ‘Global Perspectives on the Archaeology of Islands’ is planned for December 2004, to be held at the University of Auckland, New Zealand, and jointly organised by the Department of Anthropology, University of Auckland and the Institute of Archaeology, University College London. We hope this volume will provide a positive contribution to this ongoing area of research.

Acknowledgments

Many thanks go to our conference chairs – Finbar McCormick, Don Brothwell, Jacqui Huntley, Mike Baillie and Mark Dinnin – and Alan Hall for his summation. We are very grateful to all the speakers and delegates without whom the conference would not have been possible. Thanks are also due to our volunteer helpers – Rose Cremin, Thom Kerr, Ronan McHugh and Christina O’Regan – and to the School of Archaeology and Palaeoecology and Queen’s University Belfast for supporting the event. We would like to acknowledge the AEA committee for allowing us to host the annual symposium and for all its support and advice. We are extremely grateful to everyone who has contributed to the volume; our referees deserve a special note of thanks for all their hard work. We would particularly like to thank the general editor of Environmental Archaeology, Glynis Jones, for her guidance and patience during the editorial process, and Libby Mulqueeny, Queen’s University Belfast, for her assistance with illustrations.

References

• Bennett, K. D. 1997. Evolution and Ecology: The Pace of Life. Cambridge: Cambridge University Press.
• Bennett, K. D. 2004. Continuing the debate on the role of Quaternary environmental change on macroevolution. Philosophical Transactions of the Royal Society of London B 359, 295-303.
• Brothwell, D. and Dimbleby, G. (eds.) 1981. Environmental Aspects of Coasts and Islands (Symposia of the Association for Environmental Archaeology 1; BAR International Series 94). Oxford: British Archaeological Reports.
• Darwin, C. 1859. On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life. London: John Murray.
• MacArthur, R. H. and Wilson, E. O. 1967. The Theory of Island Biogeography. Princeton: Princeton University Press.
• Mulville, J., Parker Pearson, M., Sharples, N., Smith, H. and Chamberlain, A. 2003. Quarters, arcs and squares: human and animal remains in the Hebridean Late Iron Age, pp. 20-34 in Downes, J. and Ritchie, A. (eds.), Sea change: Orkney and Northern Europe in the later Iron Age AD 300-800. Balgavies: Pinkfoot Press.
• Terrell, J. E. 1997. The postponed agenda: archaeology and human biogeography in the twenty-first century. Human Ecology 25, 419-36.
• Waldron, W. H. and Enseyat, J. A. (eds.) 2003. World Islands in Prehistory (BAR International Series 1095). Oxford: Archaeopress.
• Wallace, A. R. 1880. Island Life. London: Macmillan.

Research Papers

Island Differentiation Muddied by Island Biogeographers

Sam Berry

Abstract

The effects of initial founding populations have been repeatedly undervalued by population and evolutionary biologists. Chapter 7 in MacArthur and Wilson’s (1967) classic Theory of Island Biogeography is called ‘Evolutionary changes following colonisation’. The authors begin by stating that “it is appropriate to study how natural selection acts on islands and, in particular, how it acts differently on islands as opposed to mainlands”. They go on to describe the evolution of new populations as passing through three phases: response to the effects of initial small size; adjustment to the novel features of the invaded environment; and finally speciation, secondary emigration and radiation. They claim that “the founder population is no more than the observation that a propagule should contain fewer genes than the entire mother population”. They err in this: the founder propagule will almost certainly have its genes (alleles) in different frequencies than in the parental population (Conrad Waddington called this ‘intermittent drift’ as distinct from the ‘persistent drift’ occurring in continuing small populations), while Sewall Wright “attributed most significance to wide random variability of gene frequencies (not fixation or loss) expected to occur simultaneously in tens of thousands of loci...”. It may be sensible to divide the ‘founder principle’ into a ‘founder effect’ (which leads to genetic impoverishment, elimination of immigration, and – probably – changed gene frequencies) but is only then followed by ‘founder selection’. The MacArthur and Wilson model assumes that a newly colonised population will diverge progressively from its ancestors, and therefore the amount of differentiation could be taken as a measure of time since establishment. This would be wrong and could lead to a misleading estimate of the colonisation history of a particular site.

Keywords: BIOGEOGRAPHY, FOUNDER EFFECT, NATURAL SELECTION, ISLANDS, INTERMITTENT DRIFT

The Archaeological Record of Birds in Britain and Ireland Compared: Extinctions or Failures to Arrive?

Derek W. Yalden and Robert I. Carthy

Abstract

The archaeological evidence can help to discriminate between species which never arrived on islands, the species that once were present but later became extinct, and the species that only arrived late, because of human introduction, or human modification of the island to provide suitable habitat. The archaeological record from Ireland is sufficient to allow some useful comparisons with Great Britain, identifying species (e.g. Capercaillie: Tetrao urogallus L., Black Grouse: T. tetrix (L.), Great Spotted Woodpecker: Dendrocopus major (L.)) which were once present but have probably been lost through deforestation, and others whose archaeological record is sufficient in Britain to indicate with moderate confidence that they never occurred in Ireland (e.g. Tawny Owl: Strix aluco L.).

Keywords: BIRDS, IRELAND, BLACK GROUSE, CAPERCAILLIE, WOODPECKERS, TAWNY OWL

Human Interference on Ascension Island

Stephen A. Royle

Abstract

Ascension Island, off the Mid-Atlantic Ridge, is young, isolated and had developed only a restricted range of flora and fauna before discovery in 1501 when degradation of its limited ecosystems began, following the introduction of goats and rats. Matters worsened after 1815 when the British annexed Ascension. Cats released to control rats instead preyed upon the abundant seabird population. Introduced species transformed the environment as the British attempted to ‘beautify’ and utilise their outpost for food production. During the Second World War the Americans built an airstrip, and later Ascension became a communications centre. Such activities have had further impact from shaving off the tops of cinder cones to make platforms for hardware to making some of the lava fields bristle with aerials. Further, Mexican thorn recently accidentally introduced, is colonising the lower areas of the island, transforming their characteristic barren appearance. However, goats have been eradicated, farming has ceased, and a programme to destroy feral cats brings new hope to the environment as Ascension looks to a future beyond its military role.

Keywords: ASCENSION ISLAND, ISLANDS, HUMAN INTERFERENCE, ENVIRONMENT

Reconsidering Evidence of Tasmanian Fishing

Everett Bassett

Abstract

For many years it has been accepted that prehistoric Tasmanians lost the ability to fish. This has led to the suggestion that small populations can become intellectually and culturally disadvantaged as a result of isolation and population size. This conclusion was based on assumptions regarding the value of fishing and on the significance of fish fauna found within archaeological contexts. A review of this issue suggests that fish remains from Tasmania are, instead, the result of primary butchering of juvenile seals at a few unique sites and that the prehistoric and ethnohistoric records are consistent. A framework is provided to test the contrasting interpretations.

Keywords: TASMANIA, FISHING, ROCKY CAPE, SEALING, ISOLATION, ISLANDS

From Harvesting the Sea to Stock Rearing Along the Atlantic Façade of North-West Europe

Rick Schulting, Anne Tresset and Catherine Dupont

Abstract

By 3000 BC, farmers had settled most of the small islands of north-western Europe. This implies the transportation of domestic animals by sea, sometimes over long distances, and the adaptation of herding techniques to new marine environments. While many of the same islands were in use in the Mesolithic period, the nature and extent of this use appears to have been quite different. Zooarchaeological and stable isotopic analysis converge to suggest that the diet of human communities at this time was heavily reliant on marine foods. Neolithic settlements located in the same setting offer a contrasting view. Shell middens were still present at this time, and the remains of fish, marine birds and sea mammals confirm that marine resources were still exploited, but isotopic evidence highlights their minor contribution to the diet. This, combined with the faunal dominance of cattle, sheep and pig, indicates a reliance on domesticated resources. By the end of the Neolithic, even the most peripheral islands of north-western Europe were being exploited primarily for their terrestrial resources. This paper presents evidence from selected sites in western France and Orkney, and then proceeds to offer some possible explanations for the observed patterns of small island use in the Neolithic.

Keywords: MESOLITHIC, NEOLITHIC, FAUNA, MARINE EXPLOITATION

The Mesolithic-Neolithic Transition on the Channel Islands: Adopting Agriculture in an Emerging Island Landscape

David Bukach

Abstract

An examination of how and why Channel Island society adopted agriculture is aided in this paper by an island-based approach, which stresses the social and environmental implications of island life. This paper proposes a two-stage model of neolithisation of indigenous island hunter-gathers, beginning with a phase of cooperative interaction between forager and farmer in the early stages of the transition, followed by a later phase of direct competition for island resources. A rapid shift from cooperative to competitive interaction is proposed, amplified by constraints of island biogeography, sea-level change and insularity. Islanders were ‘pulled’ toward a Neolithic world view through increased exchange, while environmental conditions and limitations on the islands ‘pushed’ indigenous island hunter-gatherers to adopt agriculture. .

Keywords: ISLANDS, AGRICULTURE, TRANSITION, BIOGEOGRAPHY, CHANNEL ISLANDS

Post-Beaker Period Death and Burial at Northton, Isle Of Harris, Scotland

Eileen Murphy, Richard Gregory and Derek Simpso

Abstract

The prehistoric site of Northton, Isle of Harris, is best known for the important settlement evidence that it has produced. A total of 15 burials, however, have also been recovered from the site. These have recently been subject to a new programme of osteological and palaeopathological analysis and radiocarbon dating, the results of which indicate that the burials date from the immediate post-Beaker period through to the later Iron Age. As such, a large proportion of them have originated from periods that have previously been poorly represented in the Western Isles in terms of funerary remains. The objective of the paper is to provide an overview of the new research on the Northton burials, and to place the findings within the broader context of contemporary funerary practices in the Western Isles.

Keywords: HARRIS, PREHISTORIC, BURIAL, HUMAN SKELETONS

Connections and Distance: Investigating Social and Agricultural Issues Relating to Early Medieval Crannogs in Irelan

Christina Fredengren, Meriel McClatchie and Ingelise Stuijts

Abstract

This paper considers approaches to the study of Early Medieval crannogs in Ireland, focussing particularly on social and agricultural issues. The architecture of crannogs suggests an act of isolation, perhaps representing an Early Medieval ideology, while their material assemblages demonstrate that people in their practical lives would have depended on others to varying extents. Previously held hypotheses concerning the association of crannogs exclusively with higher-status social groups are challenged in this paper. The perceived dominance of animal husbandry in many archaeological texts is also questioned. The diverse roles of arable agricultural products in Early Medieval society are then explored, with the use of contemporary documentary sources, in order to investigate issues beyond economic concerns. Our excavation of a crannog at Sroove in Lough Gara, Co. Sligo, provides a case study with which we can reconsider approaches to the study of crannogs in Ireland.

Keywords: ARCHAEOBOTANY, CRANNOG, EARLY MEDIEVAL, IRELAND, SOCIAL, ZOOARCHAEOLOGY

The Food Economies of Atlantic Island Monasteries: The Documentary and Archaeo-Environmental Evidence

Emily Murray, Finbar McCormick and Gill Plunkett

Abstract

Much of our knowledge of Early Medieval monastic economies is based on contemporary documentary sources. Until recently, this literary record has had little in the way of useful archaeo-environmental data to support it. This paper examines the unusually rich environmental remains recovered from the excavations at two early island monasteries – Iona, in the Inner Hebrides, and Illaunloughan, Co. Kerry. The assemblages present a key opportunity to compare and contrast the literary accounts of the monastic diet with the physical evidence, and offer new insights into the economy of early monasteries. We conclude that the archaeological record indicates a much wider food base than previously documented, demonstrating the importance of integrating both strands of evidence.

Keywords: EARLY MEDIEVAL MONASTERIES, MONASTIC DIET, IONA, ILLAUNLOUGHAN

Islands in Wilderness: the Changing Medieval Use of the East Anglian Peat Fens, England

Rachel Ballantyne

Abstract

Archaeobotanical remains from an excavated ‘low-status’ Medieval rural settlement on the fen-edge at Ely, East Anglia, England, are presented as new evidence for the relationship between farming and collected fen resources. During the Early Medieval phases of the settlement (early 8th to early 12th centuries) there is little evidence for use of fen. The assemblage is compared with other bioarchaeological and historical evidence for Medieval subsistence within the Fenland and East Anglia. It is argued that cultural values, the role of the monasteries and broader Medieval economic trends must be considered when interpreting the pattern identified at Ely.

Keywords: CAMBRIDGESHIRE, MEDIEVAL, FEN-EDGE, ECONOMY, ARCHAEOBOTANY

‘Islands’ in Holocene forests: Implications for Forest Openness, Landscape Clearance and ‘Culture-Steppe’ Species

Nicki J. Whitehouse and David N. Smith

Abstract

Human activity has undoubtedly had a major impact on Holocene forested ecosystems, with the concurrent expansion of plants and animals associated with cleared landscapes and pasture, also known as ‘culture-steppe’. However, this anthropogenic perspective may have underestimated the contribution of autogenic disturbance (e.g. wind-throw, fire), or a mixture of autogenic and anthropogenic processes, within early Holocene forests. Entomologists have long argued that the north European primary forest was probably similar in structure to pasture woodland. This idea has received support from the conservation biologist Frans Vera, who has recently strongly argued that the role of large herbivores in maintaining open forests in the primeval landscapes of Europe has been seriously underestimated. This paper reviews this debate from a fossil invertebrate perspective and looks at several early Holocene insect assemblages. Although wood taxa are indeed important during this period, species typical of open areas and grassland and dung beetles, usually associated with the dung of grazing animals, are persistent presences in many early woodland faunas. We also suggest that fire and other natural disturbance agents appear to have played an important ecological role in some of these forests, maintaining open areas and creating open vegetation islands within these systems. More work, however, is required to ascertain the role of grazing animals, but we conclude that fossil insects have a significant contribution to make to this debate. This evidence has fundamental implications in terms of how the palaeoecological record is interpreted, particularly by environmental archaeologists and palaeoecologists who may be more interested in identifying human-environment interactions rather than the ecological processes which may be preserved within palaeoecological records.