With a varied and lengthy pedigree, environmental archaeology has grown in importance in recent decades. What was once seen just as a loose collection of techniques devoted to sampling past environments has developed into an important theoretical and methodological research perspective. Quite simply, environmental archaeology is the study of past human economic, political, and ritual behavior through the collection and analysis of environmental remains (for example, animal bones, soils, and botanical remains).
Historical Background
Environmental remains did not figure very prominently in the early history of modern archaeology. Researchers and antiquarians of the 18th and 19th centuries primarily focused on architectural remains and their associated material objects. Highly prized precious metals, ceramics, and other cultural crafts were collected both systematically and quite haphazardly by various individuals, museums, and universities throughout this time period. The remains of mundane meal refuse such as fragmented animal bones and botanicals received little if any research attention and were usually discarded on the spot.
The Danish archaeologist Daniel Bruun was one of the first archaeologists on record to systematically recover animal bones from an excavation. As part of his 1896 Norse excavations in Greenland and his later work in Iceland, Bruun consistently collected the animal bones that were found as part of his research digs. Bruun believed in the possibility of having animal bones identified to species level for the purposes of simple economic and dietary reconstructions. Bruun solicited the advice and skill of Herluf Winge, the head zoologist at the Royal Zoological Museum in Copenhagen, Denmark. Winge’s early cross-disciplinary work in zoology and archaeology at the beginning of the 20th century marked an early influence for modern environmental archaeology.
By the mid 20th century, archaeology both in Europe and the Americas was still largely the domain of avocationalists operating with a wide range of methods and with little interest in moving beyond artifact classification. With the writings of the English archaeologist Grahame Clark, archaeology began to interest itself in the economic and ecological aspects of past cultural systems. Clark’s 1942 Antiquity article “Bees in Antiquity” was the official beginning of his pioneering work in environmental archaeology. From 1949 to 1951, Grahame Clark supervised the excavations of Star Carr in northeastern Yorkshire. Star Carr, with its moist, peaty conditions, revealed a wide range of faunal and botanical material that allowed Clarke the first views of early Mesolithic diet, economy, and ecology. Although Star Carr has been reevaluated more than once in the preceding years as technologies have improved, it remains as the premier example of early integrative archaeology.
Educated in the methods of Grahame Clark and influenced by the ecological theories of Julian Steward and Leslie White, the next generation of environmental archaeologists ushered in a period in which ecological theory reigned supreme. The 1960s and 1970s also witnessed a period during which university programs began to create specific environmental methodologies, such as zooarchaeology, paleoethnobotany, and geoarchaeology. With time, the ecological approaches and the more economic perspectives were incorporated into the processual theory of Lewis Binford. Throughout the 1970s and 1980s, processual archaeologists made use of the newer specialties such as zooarchaeology and paleo-botany in studying past environments and the people that inhabited them. During this period, environmental archaeology was seen more as a collection of various sampling techniques than a coherent theoretical approach.
The postprocessual critiques of the 1980s and 1990s called for a reevaluation of theories and techniques both within archaeology and cultural anthropology. Environmental archaeology has ultimately benefited from the critiques that questioned the overly deterministic systems modeling of processual archaeology. Humans are not passive actors within the social and ecological realms. Rather, humans are active participants in their environment as they create, sustain, and change their cultural adaptations. The physical environment can be seen as a record of present and past human decision making (such as in economies, our social systems, and other decisions), a record that itself is always changing. Out of this period of self-assessment emerged historical ecology. Historical ecology is credited to Carole Crumley, who saw the importance of a theoretical perspective that privileged the physical landscape as the intersection between social and ecological systems. Within historical ecology, this intersection (that is, landscape) could be studied through time as it is a historical record not only of past environment but of past human decision making as well.
Methods
Current research in environmental archaeology makes use of a wide range of techniques and specialties from the natural sciences. The three most commonly studied lines of evidence include soil science, paleobotany, and zooarchaeology. Each of these sciences offers valuable insight concerning prehistoric societies and their ecological interactions. Specialists in these areas can operate both as principal investigators with diverse research goals and technicians providing specific data for a number of ongoing projects.
Soil Science
The study of soils and sediments (pedology) is critical to the understanding of all archaeological sites. With respect to archaeological sites, the study of soils and sediments involves gaining an understanding of the predepositional (that is, before the site was formed), depositional, and postdepositional (after the site was abandoned) environments. Soil science can provide details on the exact nature of ancient sites. For example, pedology can identify whether a site was near the edge of an ancient lake or river. It can also provide details concerning the vegetation of the immediate site area (heavily wooded) and the climate at the time the site was in use. Landscape and climatic changes can also be tracked after the site has been abandoned with the use of pedological sampling and laboratory techniques.
Soil is sampled using a variety of techniques. Bulk soil is commonly collected from excavated surfaces in liter or larger samples that then undergo chemical testing. Soil can also be collected from archaeological sites in situ in the form of profile samples taken from vertical, excavated surfaces. Profile samples allow soil researchers to study the individual strata or layers of archaeological sites and their relationships to each other. Chemical measures such as pH provide valuable information about the potential survivorship of various artifact classes. More advanced measures can help assess the degrees to which humans have modified their immediate environment (as in field fertilizing). Soil profile studies help researchers understand the duration of site occupation as well as landscape changes after abandonment.
Zooarchaeology
The study of animal remains from archaeological sites (zooarchaeology) is one of the earliest environmental archaeology specialties. Because of more widely available training, zooarchaeology is more commonly used than either pedology or paleobotany. Originally, only the more interesting animal bones were hand selected from archaeological sites for study. Modern excavation methods now include sieve strategies that ensure all excavated material is screened for small bone fragments and other materials.
In the laboratory, with the aid of comparative skeletal collections, attempts are made to identify the element (for example, femur), species, age, and sex of the animals represented in a specific archaeological site. A study of the species present can provide important information concerning the general ecology of the surrounding area, diet, and overall economy of cultural groups. Hunted animals can be taken in the immediate area of the site, or they can be transported and/or traded over significant distances. In addition, domesticated animals were often a supplement to both hunted species and botanical foodstuffs. Using zooarchaeological techniques, researchers can often clarify these issues and add much to the general under-standing of an archaeological site.
Paleobotany
When preservation allows, the recovery and analysis of plant remains can provide some of the most detailed information of all of the environmental archaeology specialties. Plant materials were not only a common source of nutrition but also helped provide shelter, storage, and clothing. In addition, the domestication of certain plants and trees is seen as one of the primary transformative events in human prehistory.
Plant materials are commonly recovered from archaeological sites as part of bulk soil samples. The soil is taken to the laboratory, and the soil undergoes a flotation process, by which plant remains are separated from other less buoyant particles. The recovered plant materials are then separated into two major size classes, macrofossils and microfossils. Macrofossils are remains that can be seen without aid of magnification, while the microfossils have to be studied with various levels of magnification. Seeds and plant fibers are examples of macrofossils. Microfossils include pollen, plant crystals (phytoliths), and fungi.
The recovery and interpretation of plant remains commonly include samples from both within and beyond the limits of the archaeological site. Samples from beyond the site limits allow for the reconstruction of prehistoric vegetation communities. Plant samples from within the site limits aid in the study of food ways and economy.
Environmental Archaeology: Case Examples
As modern computer, mapping, and excavation techniques have continued to improve within archaeology, environmental archaeology has increasingly been seen as necessary to the more complete study of sites and the complex data they contain. The methods of environmental archaeology are commonly used together whenever possible, and they provide the most complete information in these situations. Interdisciplinary research of this sort is logistically difficult and often much more expensive than traditional artifact-focused research. Often, projects of this scale are cooperative agreements between several universities and research centers, each with their own focus.
While still not utilized in many regions of the world, environmental archaeology has a strong history in both the North Atlantic and the South Pacific. Researchers in these two areas have engaged in international, interdisciplinary projects that have demonstrated the powerful insights of environmental archaeology.
The North Atlantic (Iceland)
Iceland is developing as one of the key research areas within the North Atlantic for several universities participating in environmental archaeology. Iceland provides the rare opportunity of a clear-cut, well-dated dichotomy between prehuman landscape development and progressive human impact in near historic times. As Dave Burney has convincingly argued with reference to Madagascar, Caribbean, and Pacific cases of “human island biogeography,” a key issue for all such attempts to use islands as model laboratories for investigation of global human ecodynamics is both an accurate and clearly delineated arrival date for the human actors and a detailed chronology of subsequent proposed human landscape interactions to sort out causality and allow effective scale matching in modeling. The Icelandic case has not only the usual advantages provided by a documentary record over completely prehistoric cases but also probably the best current potential for such tight cross-sample chronological control of any island on earth via the study of volcanic ash layers or tephras.
Near the close of the 8th century AD, Nordic pirates, traders, and settlers began the expansion from their Scandinavian homelands that gave the Viking Age its name and permanently changed the development and history of Northern Europe. In the North Atlantic, Viking Age settlers colonized the islands of the eastern North Atlantic (Faeroes, Shetland, Orkney, Hebrides, Man, Ireland) by circa AD 800. Iceland was traditionally settled circa AD 874, Greenland circa AD 985, and the short-lived Vinland colony survived a few years, around AD 1000, in the Newfoundland/ Gulf of St. Lawrence region. Prior to the 1970s, most scholars of the Viking period were philologists, medieval archaeologists, and documentary historians, and the uneven written record for Viking depredations in Europe and the colorful and diverse saga literature of Iceland tended to dominate discussion of the period. Since the mid-1970s, research has shifted, as multiple projects combining archaeology, ecology, and history have been carried out all across the region, producing a richer understanding of the Norse migrations and placing them in an environmental and economic context. The value of the diverse cases provided by the Norse North Atlantic (initial spread of a homogeneous population into different island ecosystems, subsequent economic and social diversification, total extinction of the Vinland and Greenland colonies) has been increasingly appreciated by environmental historians, natural scientists, and anthropological archaeologists.
Frequent volcanic tephra (ash) layers within soil profiles can be used to define isochrones, or time horizon markers. The three-dimensional reconstructions that can be created by mapping a series of tephra layers allow detailed data on spatial patterns. Each tephra layer marks a land surface at a “moment in time,” and multiple tephra layers constrain the passage of time and define the rate at which change has happened across a landscape. Tephras can be used to correlate precisely between cultural deposits in middens, archaeological structures, and distant landscape elements such as boundary walls, geomorphic features, and paleoecological sample sites. Furthermore, as tephra are formed within hours or days, the distribution of any one tephra through soil or in contexts that are not contemporaneous with the initial eruption can be used to identify the pathways taken by sediment through the environment, including temporary sediment stores, reworking of sediments, and movements of sediments within profiles. Tephra (in many areas falling at least once a decade) provide isochrones covering hundreds of square kilometers but require expert long-term study for effective geochemical characterization and conclusive identification. While radiocarbon dates are regularly employed in combination with tephra (and with artifact analyses provide independent dating that has generally supported the tephra chronology), Icelandic tephrachronologies are a key integrative resource for fieldworkers.
Iceland’s documentary record (sagas, law codes, annals) provides rich evidence for a socially complex nonstate society that has been employed by historians and anthropologists for studies of Iceland and the development of general theories of chieftainship. Medieval and early-modern documentary sources require critical handling but provide a rich record of landholding patterns, legal codes, stock raising, demography, conflict and competition, and invaluable access to internal worldview. Later records produced after the transition to statehood in AD 1264 have provided the basis for historical climatology documenting the impacts of sea ice and early medieval climate fluctuations. A particularly detailed farm-by-farm stock and census record (1703-1712) provides an invaluable synchronic picture of the early 18th century and has been used as a baseline for regional landscape analyses. Icelandic soils, forestry, and agricultural scientists have actively participated in these historical land use projects, and their further collaboration is being aided by special American and Icelandic research agreements.
Since the early 1980s, genuinely interdisciplinary field research by Icelandic, United States, and United Kingdom scholars has provided a mass of new ecological and archaeological data, covering most portions of the country but with special focus on the South and the North. In zooarchaeology, known animal bone collections increased from 4 to over 65, including massive 50,000 to 100,000 identifiable fragment samples spanning the period from first settlement down to the later 19th century. The formation of the FSI (Institute of Archaeology Iceland) in 1995 by a group of Icelandic scholars has further stimulated survey and excavation work and direct cooperation.
Iceland was first settled during the Viking Age, and human impact on local animal, vegetation, soils, and drainage patterns was rapid and profound. By AD 950, 80% of the native woodlands had been cleared, and soil erosion had begun in higher elevations. By the Middle Ages, this loss of ground cover led to more widespread erosion of approximately 40% of the top-soil present before human settlement (see Figure 1). Iceland thus represents an extreme case of preindustrial human impact on the environment increasingly well documented by archaeology, history, and natural science. How the early Icelandic political economy interacted with and was shaped by the natural environment is of considerable relevance to modern societies in the developed and developing world subject to some of the same interactions of economy and landscape, with some of the same long-term results for genuinely sustainable development.
The Pacific (Hawaii)
Although still not fully understood, successive migrations out of Southeast Asia into the Pacific islands fueled the development of a Polynesian culture. By the first half of the second millennium D, Polynesian voyagers had made their way to the Hawaiian archipelago, which had until then been free of human habitation. The Hawaiian Islands are fertile, high islands, and they were ideal for the intensive agricultural methods utilized by Polynesians settlers. Until recently, it was widely accepted that Hawaii’s “pristine” presettlement environment was little affected by the Polynesians. Multinational, interdisciplinary research throughout the Pacific has begun to reveal a more complex history of human/environmental interaction. The Hawaiian Islands are among the most intensively studied in this respect as paleobotany, soil science, and zooarchaeology continue to shed new light on the environmental effects of both the Polynesian and later European settlement.
Modern environmentally focused research in Hawaii is first credited to Roger Green and his introduction of the “settlement pattern” approach in the 1960s. The “settlement” approach was primarily concerned with how the first human settlers adapted to specific island habitats. However, after the excavation of the limestone sinkholes at Barber’s Point, Oahu, researchers began to question the idea of Polynesians adapting to a static and unchanging environment.
Barbers Point revealed evidence of bird and snail extinctions immediately after the arrival of the first settlers. While the bird remains were evidence of predation, the extinct snails represented changes in the general ecology of the island. In the early 1980s, Patrick Kirch and a team of environmental specialists began a comprehensive research program to fully investigate the ecological impact of Polynesian settlement. Using historical records, pollen, soil, and faunal samples, researchers working in Hawaii have been able to detail the progression of human/environmental interactions since Polynesian settlement.
Accounts from early Hawaiian missionaries and travelers made note of the fern and grasslands throughout the lowland regions of the islands. Pollen diagrams taken from lowland swamp areas of Oahu indicate pre-settlement vegetation characterized by various palm species, including Pritchardia, which is now quite rare. Pollen diagrams showing declines in Pritchardia and other now rare lowland shrubs began by AD 800 and advanced thereafter. Researchers suspect that palm forests were cleared to make space for agricultural purposes. These areas never regained their presettlement forest cover, but remained the domain of grasses, shrubs, and ferns. Additional botanical analyses of charcoal from archaeological sites in Hawaii indicate the initial burning of many dry-land tree species that are now much less represented in the landscape.
The study of various land snail species (terrestrial gastropods) has also helped reveal the changing ecology of early Polynesian Hawaii. Terrestrial gastropods were able to naturally colonize the Hawaiian Islands before human arrival and were represented by over 800 species. These small snails were of little economic importance to early Hawaiians, but their adaptation to very specific ecological habitats make them ideal for recreating the immediate environment of archaeological site areas and their transformation over time. A common gastropod sequence for Hawaiian sites shows closed-canopy forest-adapted snails being replaced with more open-area species.
Zooarchaeology within Hawaiian research has also shown the rather dramatic impact of Polynesian settlement on native bird life. To date, 55 species of birds are known to be native to the Hawaiian archipelago. According to archaeological research, 35 of these species were exterminated between early Polynesian settlement and the first arrival of Europeans. This list of now extinct birds includes flightless geese, a hawk and eagle, as well as several rail species. Researchers believe that the reasons for these bird extinctions are multiple and often intertwined. Many of the bird species were used as food as well as a source of decorative feathers. Polynesian-introduced animals (dog, pig, and rat) were also responsible for the destruction of many bird habitats. Further habitat destruction on the part of Polynesian farmers led to the demise of still other bird species.
Geological and soil research in the Hawaiian Islands has been able to show the tandem effect of a growing population and its increasing demands on the agricultural production of an island environment. From an estimated settlement population of hundreds in the first half of the second millennium AD, Hawaii’s estimated population had bloomed to several hundred thousand by the time of European contact in 1778. The demand for more agricultural area is reflected in a general archaeological pattern seen throughout the Pacific. During the initial settlement period, deforestation is prominent as land is cleared for farming and building materials. Due to excessive ground cover removal, highland areas begin to erode. This erosion and associated deposition in lowland valleys is noted in soil profiles throughout Hawaii.
Human Ecology, Past, Present, and Future
The bounded ecosystems of island archipelagos like Hawaii and Iceland provide ideal research laboratories for studying the complex multifaceted interactions of humans and their environment. The interactions between prehistoric political economic systems and the natural environment in which they are intricately imbedded are not fully understood. What has become clear in recent decades is the importance of interdisciplinary research drawing from wide areas of expertise. Individually, researchers cannot fully explore or understand the complex dynamics of human decisions regarding the natural environment in which we all live. With such issues as climate change and global warming receiving more and more attention in recent years, the call for a more thorough understanding of human/environmental dynamics has increased within the United States and Europe. Environmental archaeology provides an anthropologically informed understanding of human ecology with a time depth not available to other perspectives. A well-understood past is important to any discussion of present and future human/ environmental conditions.
References:
- Albarella, U. (Ed.). (2001). Environmental archaeology: Meaning and purpose. London: Kluwer.
- Dincauze, D. (2000). Environmental archaeology: Principles and practice. Cambridge: Cambridge University Press.
- Housley, R. A., & Coles, G. (Eds.). (2004). Atlantic connections and adaptations: Economies, environments, and subsistence in lands bordering the North Atlantic. Oxford: Oxbow Monographs.
- Kirch, P., & Hunt, T. (Eds.). (1997). Historical ecology in the Pacific Islands. New Haven, CT: Yale University Press.
- Redman, C., James, S., Fish, P., & Rogers, D. (Eds.). (2004). The archaeology of global change: The impact ofhumans on their environment. Washington, DC: Smithsonian Institution Press.