Key Points
- Archaeologists have debated for decades over how Mississippian-style pottery ended up in Tampa Bay, an area long left off of maps showing the Mississippian culture stretching across the Southeast and into northern Florida starting a thousand years ago.
- Trevor Duke, a doctoral student working at the Florida Museum of Natural History, recently undertook compositional and chemical analyses of the pottery. The research eventually expanded as scientists compiled additional evidence from across the region.
- The results of that research have been published in a new study in which the authors concluded that migrants from the Florida Panhandle, in the heartland of Mississippian culture, likely used their specialized knowledge and access to resources to produce the distinctive pottery in Tampa Bay, potentially establishing themselves and integrating into the region’s existing society in the process.
GAINESVILLE, Fla. --- About a hundred years ago, archaeologists unearthing pottery sherds in Tampa Bay found something unexpected. Some of the fragments they recovered had designs that were nearly identical to decorated pottery located hundreds of miles to the north. At least on the surface, the pottery appeared to be Mississippian, a culture that emerged over a thousand years ago and brought social, economic and political transformation across southeastern North America. For years, archaeologists excluded peninsular Florida from maps of its range, but the artifacts suggested a different story.
“It’s been this open debate for a century,” said Neill Wallis, curator of Florida archaeology, bioarchaeology and the Ceramic Technology Laboratory at the Florida Museum of Natural History. “Tampa Bay sites had some Mississippian-like traits such as platform mound-village complexes and iconography, but lacked others, like maize agriculture and shell-tempered pottery. The Mississippian-looking pottery has always begged the question: How did this stuff wind up in Tampa Bay?”
Finding Mississippian pottery would provide some of the clearest evidence of the region’s connection to the culture, but the surface-level designs themselves weren’t enough to determine where the pottery originated. Without the proper instruments and expertise, curators shelved the mysterious pottery sherds. Various theories lingered without conclusive evidence - until recently, when researchers at the Florida Museum conducted a study to track down the answer.
“We were curious to find out if these vessels were imported from the heartland by trade, if they were local imitations of Mississippian motifs, or, as we ultimately found, if they were made by migrants who had made their way into communities in Tampa Bay to take up shop and residency there,” said Trevor Duke, who began conducting the research for his doctoral dissertation at the University of Florida. In the years since, Duke and his colleagues have expanded on the initial scope of his dissertation to compile more evidence from a larger collection of samples.
The researchers were able to look beyond the surface designs of the vessels to uncover the small, nearly invisible details of production baked into them. In doing so, they traced this decorated pottery back to a secretive community of artisans who likely traveled hundreds of miles from the heartland of Mississippian culture to their new home in Tampa Bay. Compared with the plain, molded wares commonly found throughout the region, the decorated pottery’s distinct high-quality clay, temper and production method indicate this group of migrants had access to both specialized knowledge and resources that the existing residents did not.
A cultural revolution spans the Southeast
Around 1000 A.D., a new culture took root in the Mississippi River Valley and radiated outward, eventually covering much of what is now the Midwest and eastern United States. In the heartland, Indigenous communities settled into regional hierarchies, with large chiefdoms amassing political power over surrounding villages. They planted large swaths of land with maize and quarried soil to build large mounds topped with temples and chief residences.
But Safety Harbor, the term used for the regional culture that existed in and around Tampa Bay during this period, sat on the outskirts, hundreds of miles south of tribes associated with the Mississippian culture. Like these Mississippian tribes, Safety Harbor communities aggregated in small chiefdoms and built flat-topped mounds. The largest village of Safety Harbor was home to the Tocobaga, with smaller Mocoso, Pohoy and Uzita chiefdoms dotting the surrounding region. But no single group gathered as much political power as the central hubs of the north. Furthermore, the coastal communities never adopted the hallmark maize agriculture, sustaining themselves with fishing and marine resources instead.
Given these mixed signals, archaeologists have never fully understood the extent of the connection between these coastal communities and the Mississippian heartland. Uncovering pottery with Mississippian designs in Tampa Bay only further stoked the debate.
To track down the answer, Duke and other archaeologists at the Florida Museum gathered a collection of 58 plain and decorated pottery sherds from Tampa Bay for closer analysis. Both types of vessels would have been used for cooking and serving throughout the community, but the decorated pottery was likely reserved for special occasions.
During this period, Mississippian potters began tempering their clay with crushed freshwater shell or pieces of old pottery called grog. They also began shaping their vessels by stacking coils of clay instead of molding it. If the decorated pottery in Tampa Bay was truly Mississippian, either brought by trade or crafted with the knowledge of Mississippian-trained artisans, archaeologists would see evidence of these techniques in the artifacts. On the other hand, if the decorated vessels were mere imitations of Mississippian styles that local potters saw from afar, researchers would find the region’s commonplace methods, such as sand tempering, beneath the decorative motifs.
Combining local sources and faraway skills
First, the study authors measured the chemical composition of the artifacts using neutron activation analysis to determine if the clay was locally sourced. They compared the composition of the pottery sherds with that of raw clay sources found around the region. The two chemical profiles matched, meaning that all the pottery was made on-site. This excluded the theory that the artifacts were made in the Mississippian heartland and arrived by trade, but scientists couldn’t yet rule out that the vessels were imitations.
Turning to a microscope, the researchers got a closer look at what potters were mixing into the clay during the production process. In an analysis called petrography, scientists slice off a thin section of a pottery sherd and polish it down until it is about half the width of a human hair. The light of a polarizing microscope can pass through the section and allows archaeologists to analyze the little voids, cracks and grains as clues to how the clay was processed.
“Looking at the section under a microscope, you can identify the minerals in it based on their color and shape. From that, we can figure out what was added to it. It’s a sort of fingerprint of the people who made it,” Wallis said.
This was where the Tampa Bay pottery really turned interesting.
Several of the decorated fragments were tempered with grog, a characteristic of some Mississippian pottery. Mixing crushed pottery into the clay improves the vessel’s quality by helping it withstand the high temperatures of firing and cooking.
“This grog tempering is not something that we saw previously or in the plain samples in Tampa Bay,” Duke said. “But up in the Tallahassee Hills, where the nearest massive Mississippian mound center is located, it’s common in all vessels. It’s the plain-Jane tempering technique there.”
It was more than technique connecting this pottery to the Tallahassee Hills, located some 200 miles north of Tampa Bay. Within the grog temper, scientists identified mica, a shiny silicate mineral common to the Panhandle but not typically found in peninsular Florida. The clay of the host pot may have been local to Tampa Bay, but the particles that had been mixed with it appeared to be from the Mississippian heartland.
While 80% of the decorated pottery in the sample contained grog, not a single piece of plain pottery did. Most plain vessels contained chunks of dry clay or sand, a temper used for both plain and decorated pottery for the previous 3,000 years.
This was not the only distinction between the two styles. The decorated pottery showcased the Mississippian method of shaping the vessel by coiling and was made with more consistent paste recipes, suggesting the potters had greater knowledge of how to process the clay. Meanwhile, the plain wares were molded, a simple practice that became more popular as the region saw an increase in population. The technique could quickly be picked up by those without pottery skills.
The more the analysis revealed, the more pieces of the puzzle fit together. All of this lends itself to the idea that potters from the Mississippian heartland brought both knowledge and resources with them from their homeland. As the migrants traversed the landscape from northern Florida, they would have carried a bag of old pottery made of clay from their homeland. Arriving in Tampa Bay, this decorated pottery would be crushed, ground and worked into the fresh clay of their new home.
Beyond function, this cache of grog likely held meaning to the migrants. They reserved the decorated pottery of their homeland for this purpose. Every grog-tempered vessel contained a piece of multi-generational grog, which is when a piece of grog is embedded within another, larger piece of grog. They are tiny pieces of their homeland that they incorporated into all the vessels, even the ones they’re making in their new home in Tampa Bay.
“It’s sort of like Russian nesting dolls because you have grog within grog within grog. You can trace this back several generations of pots,” Wallis said. “And they’re not using vessels from just anywhere. They’re crushing up the same decorated vessels that include pieces of decorated pottery from before.”
Their advanced pottery-making skills and connection to Mississippian culture may have helped the migrants establish themselves in an unfamiliar place, transforming the commonplace traditions of their homeland into unique skills valued by their new community.
“Migrant communities often had to figure out their own niche in a new place,” said Andrea Torvinen, collections manager of the Ceramic Technology Lab and Florida Archaeology at the Florida Museum. “What would have made these migrants stand out? How would they have established a role in this new area? Bringing a specialized knowledge of pottery production seems to have been one way they could do so.”
These skills were coveted, and resources were limited, which is why archaeologists only see evidence of them in decorated pottery while the plain, everyday vessels continued to be produced by novices using low-skill and existing techniques. The decorated vessels were also made of higher-quality clays than the plain pottery, indicating the migrants making these vessels were granted access to a limited resource of high-quality materials for their craft.
Maintaining the secret
This distinction between decorated and plain pottery persists for centuries. But why did local residents not simply pick up the new skills? Whether intentional or not, the secrets of the trade would have been confined to a small community of crafters working alongside one another.
“The group of potters making the decorated vessels likely had some kind of special status that they maintained through this secretive practice, even if it wasn’t a secret in the sense that no one knew about it,” Wallis said. “In fact, for secrets like this, you do have to broadcast some of the details so that people know there is a secret.”
The high-quality, decorated pots would have been circulated and valued around the community, but the tempering, coiling and consistency are not clearly visible in the finished product. Therefore, they’re not easily mimicked. Without intimate access to this tight circle of migrant potters, the existing Tampa Bay residents would not have been able to adopt the skilled practices themselves.
“People with specialized skills have direct relationships with the people learning from them. That's how we see knowledge passed down. When it’s the way your mentor has always done it, that’s how you’re going to do it,” Torvinen said. “And in this case, there could have been a more meaningful reason behind it. By tying the homeland pottery into this enchainment, they’re bringing those pots with them into the next generation.”
The study was published in American Antiquity.
Journal
American Antiquity
