Current Research: Laboratory of Landscape Archaeology

Landscape archaeology is the study of ancient social geographies, or how communities modified, experienced, and interacted with past environments.

Research in the Laboratory of Landscape Archaeology (LLA) at the University of Oklahoma examines multiple dimensions of landscape use, including environmental exploitation and modification, settlement and mobility, interaction between communities, the construction of sacred venues, and the implications of past practices for current and future landscapes. Understanding ancient landscape modification has implications for contemporary transformations of the environment.

Students interested in any of the following should contact lab director Asa Randall, there are plenty of interesting questions to ask, lots of data to be gathered from extant collections, and many opportunities for conducting your own research in the LLA or in the field.

Freshwater St. Johns River, Florida

St. Johns River near Deland, USFDigital_D32-2775
Turn of the century postcard of the St. Johns River. Courtesy of the USF Digital Collections.

Ongoing research at the LLA is focused on the freshwater St. Johns River in northeast Florida. This portion of the river flows from its headwaters in south central Florida, between the modern day cities of Vero Beach to the south and Palatka to the north. Below Palatka, the river is brackish until its confluence with the Atlantic. The river is sometimes referred to as the “River of Lakes,” so-called because of its sluggish pace and habit of alternating between channels and open bodies of water. Also significant are the many freshwater springs which eminate from underground limestone vents fed by the Floridan Aquifer. Although it is pictureseque and ecologically diverse, the slow moving St. Johns River is equally susceptible to sea level flcutations, variable precipitation, and modern channel dredging and agricultural practices. The region’s long history, coupled with concerns regarding contemporary environmental and cultural resource impacts from development and recreation, make it an ideal location to examine the many dimensions of landscape use in the past and today.

The ancient St. Johns River landscape was inhabited and modified by hunter-gatherer communities. Early habitation of the region, during the Paleoindian and Early Archaic periods, remains poorly understood because much of the lower-lying portions of the river valley were inundated by sea level rise after 8000 years ago. Terrestiral and underwater testing often encounters evidence for these time periods near springs or along old banks of the river. Archaeologically, the region is perhaps best known for the many shell mounds that once dominated the landscape. Current data indicates that shell mounds were constructed at least as early as 7400 years ago, during the Mount Taylor period (7400-4600 years ago), and continued to be used and modified in a variety of ways during the subsequent Orange (4600-3500 years ago), St. Johns I (3500-1250 years ago), and St. Johns II periods (1250-500 years ago). Since the 16th century, the region has undergone a number of social, demographic, economic, and land use transformations.

Below you will find brief descriptions of current freshwater St. Johns River research at the LLA. Some of this research is conducted in affiliation with the Laboratory of Southeastern Archaeology at the University of Florida (UF-LSA), often in collarboration with the Florida Department of Environmental Protection-State Parks, the U.S. Forest Service, the U.S. Fish and Wildlife Service, and private parties. The 2012 University of Oklahoma archaeological field school was conducted on the St. Johns as well (view the preliminary results of the field season here).

Locating, Mapping, and Reconstructing Shell Mounds

Digitally reconstructed topography of the Silver Glen Springs watershed prior to shell mining (ca. 1874).
Digitally reconstructed topography of the Silver Glen Springs watershed prior to shell mining (ca. 1874).
MinedMound
1941 Aerial photograph of mined shell mound (outlined in red).

In the 18th and 19th centuries, explorers, antiquarians and archaeologists encountered scores of shell-bearing sites, the largest occurring every 1 kilometers or so. Indeed, early descriptions indicate that the St. Johns River valley had been intensively and extensively modified prior to Euro-american settlement. Some shell sites were small, no more than 50 cm high, while others were monumental in scale, greater than 300 meters in plan and up to 10 meters high. Some shell mounds had burial mounds constructed on or adjacent to them. Unfortunately, very few of these mounds remain in their original state today. By the 1960s, the vast majority had been carted away by hand, or at the ends of draglines, for use as road aggregate. Although they have been physically altered, or even obliterated, there is much that we can learn about ancient hunter-gatherer and modern landscape use from shell mounds.

The LLA is currently building a spatial database of site locations, configurations, and – when possible – topography by digitizing and combining a variety of archival and remotely sensed resources. The sources include pre-mining observations, excavation data, historic aerial photographs, modern aerial photographs, and LiDAR. Not only is it possible to characterize intact mounds, but in certain cases we can digitally reconstruct and visualize ancient landscapes.The amassed database provides a means to compare site plans within and between regions, to test models of social organization based on above-ground architecture, and examine how past communities referenced “natural” features such as channels, wetlands, springs, and even celestial bodies. The project is ongoing, but it is clear that the St. Johns River was extensively terraformed with a diverse assortment of shell and non-shell bearing places. Published results can be viewed here.

Shell Sites in History

Excavation of Relict Shell Mound
Excavation of a Relict Shell Mound

Knowing the location and final form of places is important, but to understand how different places may have interacted (or were integrated into a network) at particular moments across the landscape requires excavation. Detailing the history of particularly locations is especially important on the St. Johns River, where certain places were created, modified, and built upon over the course of many millennia. We now understand that the past was very important to ancient inhabitants of the St. Johns region: they routinely reused ancient places for the construction of monuments, burial mounds, or other sacred venues. Understanding these long-term and multi-scalar dynamics is cerrtainly complicated, however, by the near-destruction of most shell mounds. Some remain intact, such as the Hontoon Dead Creek Mound, which can be visited at Hontoon Island State Park.

Recording stratigraphy at an Archaic period shell mound
Recording stratigraphy at an Archaic period shell mound

Surveys and excavations at a number of sites on the middle St. Johns River reveal the complexity of landscape alteration. Surveys have focused on documenting the full range of variation in shell and non-shell sites. While less visual obvious in comparison to mounds, information from small sites further demonstrate how the St. Johns region contained a complex network of places through time. Stratigraphic excavations have emphasized sites impacted by shell mining, or which were under threat from development. These projects have produced a wealth of chronological, cultural, and environmental data. Shell sites contain a wide array of features, including processing pits, midden deposits, prepared floors, and mounded deposits. Much of this data has been made publically available through technical reports.

This research, coupled with archival examinations of early excavations, is providing the detailed chronologies from many different contexts across the region necessary for understanding complex landscape dynamics. We now know that shell mounds had very different lives, some were built within a few generations, while others accumulated over the course of millennia (a recently published regional chronology of Mount Taylor period shell mounds can be downloaded here). Some shell sites were constructed as residential spaces, only to be transformed into ceremonial places much later in time. Ramps, sand mounds, and other architectural elements were also constructed. Many questions regarding the symbolic or practical significance of these construction events, and the religious and political traditions that underwrote them, remain to be addressed.

Diet and Deposition

Well-preserved fish bone concreted with freshwater shell, from a 6,000 year old shell mound.
Well-preserved fish bone concreted with freshwater shell, from a 6,000 year old shell mound.

Shell-bearing sites were first introduced to the archaeological community in the early 19th century by scientists studying Mesolithic period shell mounds in Denmark. At the time, one of the more remarkable aspects of these sites was the incredible preservation of archaeofauna and archaeobotanical assemblages. The density of finds inspired the Danish scholars to interpret these particular shell mounds as trash heaps, or middens (so-called kjökkenmöddinger). This particular interpretation was extended in archaeological thought to all shell sites in the following century and a half. For many researchers today, shell sites are ideal contexts to reconstruct the diet and environment of past communities. While appreciating that the remains of plants, vertebrates, and invertebrates found in shell sites can provide unique insight into past landscape use, the deposits from which these assemblages are derived need to be historically and socially contextualized. Recent discoveries on the St. Johns River, the Atlantic Coast, and along the Ohio River valley have prompted new discussions of the significance of shell mounds, their contents, and the role of depositional practices in creating social spaces.

Shellfish processing pit with complex fill sequence.
Shellfish processing pit with complex fill sequence.

The detailed site histories that have been generated by field research provide a unique framework for examining the contexts in which shellfish and other resources were exploited, processed, and ultimately incorporated into the archaeological record. Initial results highlight the complexity of depositional practices. Shellfish, for example, were exploited for small meals, but also apparently for feasts. The resulting shells were also used as a construction medium, either in mortuary contexts or in large ceremonial aggregation sites. Complex fill sequences across mound surfaces, or within pits, were likely intentionally emplaced, and not simply the result of haphazard trash disposal. Many examples of old midden being moved and repurposed to construct sacred places suggests that midden materials had complex lives within communities. Continued work will trace dietary practices in time and space with respect to changing patterns of social organization.

Paleoclimate and Social Change

Soil Tube
Examining the contents of a soil tube extracted from a shell-bearing site.

The St. Johns River was popularized in western thought through the writings of William Batram, a naturalist and astute observer who chronicled his travels throughout northern Florida. His wonderfully detailed and flourished accounts of the flora, fauna, and human inhabitants of the river invoked a sense of timelessness, giving the landscape an almost primordial character that was adopted by later visitors. Archaeological and paleoclimatological research challenges this view of an unchanging landscape. We now know that the St. Johns River is a complex system, whose hydrological character and ecological structure has changed many times throughout the Holocene. In the last century alone major changes have been wrought by drainage of the headwaters, channel dredging, the introduction of nitrates and bacteria into the system, and even shell mining.

4,000 year-old carbonized and uncarbonized organic matter from a shell-bearing wet site.
4,000 year-old carbonized and uncarbonized organic matter from a shell-bearing wet site.

Archaeological evidence for environmental change can be found in the distribution of sites today, as well as the disposition of archaeological deposits above or below the water table. The regional site database reveals all manner of ruptures and transformations in the scale and intensity of site use and resource exploitation, some of which appear to relate to hydrological change. For example, prior to 7,500 years ago, peninsular Florida was generally drier than today, and rivers likely flowed faster. After 7500 years ago, the region became significantly wetter, and one consequence seems to have been the expansion of aquatic habitats for shellfish and other species. Today, the earliest shell mounds are found up to 200 m away from flowing water. Yet, 7000 years ago, they were sited adjacent to lagoons or channel segments. Geoarchaeological investigations, coupled with judicious comparisons with regional paleoproxy data, can reconstruct the environmental contexts of these and later mounds.

In addition to terrestrial deposits, many sites on the St. Johns river contain so-called wet site, or saturated, deposits. These are anthropogenic deposits that have been persistently saturated, either because materials were deposited in water, or a terrestrial site was subsequently innundated by rising waters. Wet-sites have incredible preservation of organic deposits: wooden tools and canoes, uncharred bone, and in some cases the flesh of fruits may be preserved. These resources provide crucial windows into past resource exploitation. Of equal importance are naturally paleohydrological indicators – such as peat, muck, or commensal shellfish – which can help reconstruct the character of wetlands or identify significant past climate events. When integrated with the results of detailed site histories in time and space, the paleoclimatic data provide a powerful means to examine how communities reacted to, or interferred with, past climate variations. The results have significance not only for how we understand ancient social change, but also for problematizing future cultural responses to landscape change.

Technology, Community, and Interaction

Objects from shell and non-shell sites. From left to right: marine shell axe, lithic hafted biface, bone tools.
Objects from shell and non-shell sites. From left to right: marine shell axe, lithic hafted biface, bone tools.

Inhabitants of the region crafted tools from a wide variety of media, including marine shell, stone, bone, antler, wood, and clay. Many of these objects provide insight into the happenings of everyday life. Marine shell, for example, was transformed into cooking vessels and wood working tools such as axes and adzes. Preserved canoes attest to the use of these tools for production, and analysis of paleoclimate data may determine that these tools were used for land clearing as well. Bone and atler found a variety of uses, from net gauges to projectiles. Lithic tools attest to diverse resource exploitation practices and media modification. After 4600 years ago, communities produced pottery for mundane and ritual purposes.

Objects can inform us about how inhabitants of the St. Johns River managed local resources. However, many classes of material culture also provide insight into the broad spatial horizons and social interactions that St. Johns River inhabitants experienced. Excluding wood, bone, antler, and some clays, the tools on the St. Johns were produced

Archaic period bannerstone found by C. B. Moore at the Thornhill Lake site, likely from the Savannah River valley region.
Archaic period bannerstone found by C. B. Moore at the Thornhill Lake site, likely from the Savannah River valley region.

with non-local materials. In peninsular Florida, lithic resources are situated in the central and Gulf Coastal regions. Analysis of lithic resources by several Florida scholars have demonstrated that the provenance of stone tools manufactured from chert can determined with high accuracy. While raw toolstone could be found within 50 to 100 km of the St. Johns basin, regional inhabitants aquired material from throughout the state. Marine shell could be harvested from either coast, although certain species could only be aquired from southeastern Florida. The presence of both lithic and marine shell objects attest to connections outside of the St. Johns river. Some of this material may have been aquired during seasonal mobility: stable isotope analysis of Archaic populations indicate a long-term pattern of movement between winters spent on the St. Johns River and summers spent on the coast. Other objects found on the St. Johns River attest to even farther social connections. For example, so-called bannerstones are often found in middle Archaic sites on the St. Johns. These ground stone objects were definitively not produced on the St. Johns, and many were likely aquired from the Savannah River valley of Georgia and South Carolina (for a discussion of bannerstone production and history click here). Research in the LLA continues to explore the social networks of communities by placing finds – from lithic debris to items of personal adornment – into their social, historical, and spatial contexts through excavation and provenance studies.

The Florida Explorations of Jeffries Wyman

During the 19th century, shell site investigations on the Atlantic seaboard were a critical nexus of persons, ideas, and methodological innovations that led, eventually, to a scientific American archaeology. One notable figure in this process was Jeffries Wyman, first curator of Harvard’s Peabody Museum of American Archaeology and Ethnology. Wyman’s posthumously published monograph, The Fresh-Water Shell Mounds of the St. John’s River, Florida (1875), relates his observations of the structure and content of at least 48 shell-bearing sites and sand mounds, and provides interpretations of how they formed. Importantly, his report included a number of techniques that would become

Camps and sites visited by Wyman during the years 1867, 1871-1873.
Camps and sites visited by Wyman during the years 1867, 1871-1873.

commonplace in Americanist archaeology later, in some cases not for another 50 years: stratigraphic recording and interpretation, taphonomy, paleoecology and hydrology, pottery typology, zooarchaeology, bioarchaeology, comparative ethnographic analogy, recognition of different ancient cultures, and a relative chronology based on stratigraphy and material culture.

Equally striking is the regional scope of the work, large sample size, and a high level of detail provided for many locations. Wyman’s research influenced a number of central figures in archaeology. He was also a vector, by way of European scholarship, for prehistory as a science of human development based on ethnology and geological principles. Wyman’s descriptions of shell sites continue to be an important resource for Florida archaeologists as well. The majority of the places he visited have been significantly altered or destroyed in the last century.

One significant critique of Wyman’s research regards his methodology, which is nowhere clearly described in the monograph. At the LLA, Wyman’s methods and travels are being reconstructed through an analysis of his collections and field journals (curated at Harvard’s Peabody Museum and Countway Library of Medicine, respectively). The bulk of his fieldwork was conducted on the St. Johns River, but also extended along the coast of Peninsular Florida. The goal is to determine specifically how Wyman conducted his research in the field and the laboratory, and determine how his methods affected his and future interpretations of shell sites. Wyman kept a daily journal during his travels on the St. Johns in 1867 and 1871 through 1873, and one relating an 1869 trip around the Peninsula’s coast. The fieldbooks contain a wealth of unpublished data, including the frequency and duration of site visits, stratigraphic drawings, and a few site plans. They also reveal Wyman’s changing interests, conclusions, and methods. As a first step, Wyman’s expeditions were mapped in a modern GIS geodatabase. Current work involves transcribing all of the journals, and reanalyzing his Florida artifact collections. The initial phase of this project was funded by a generous grant from the American Philosophical Society.