Understanding Social and Ecological Impacts of the Horse in the Greater Mississippi
The initiators of the Horses, Donkeys, and the Anthropocene in the Greater Mississippi project provide an update on their findings, drawing attention to the historical bias that has typically influenced research tracing the arrival of horses to the region—and, as a result, our understanding of the landscape as a whole.
Fig. 1. Horse historical remains identified, sampled, and analyzed through ongoing pilot work, juxtaposed with the project’s general region of interest (gray ellipse).
As of October 2019, the Horses, Donkeys, and the Anthropocene in the Greater Mississippi project has successfully identified and analyzed archaeological horse remains from across a wide region of the greater Mississippi Valley—including ancient sites from Oklahoma, Missouri, Kansas, Nebraska, and the Dakotas (Fig. 1). Although much of our research sampling took place in June of 2019 and laboratory results are, at time of writing, thus still in progress, this inquiry has brought us several crucial discoveries so far. These outcomes and new discoveries are summarized below.
1. Many ancient horse remains from the Mississippi Region have been misclassified as “Ice Age” or modern horses—and these provide a crucial dataset for understanding human-environmental interactions across the region. Our work has revealed a large number of horse skeletons that incorrectly assigned as early or late, based largely on the assumption that horses are a European animal and their occurrence in archaeological sites is likely to be a modern intrusion (Fig. 2). Radiocarbon dating of these specimens shows that many museum collections hold early materials useful for the scientific study of horses and their introduction into native cultures in the Mississippi Region.
Fig. 2. Left: Spanish chainmail and horse teeth recovered from a Great Bend Aspect site in Kansas (the Saxman site), currently dated to the early 17th century. Right: horse burial from this locality informally excavated and disposed of during the 1970s, on the assumption that it was modern.
2. Native people in the Mississippi Region have had domestic horses since the early 17th century—much earlier than is often suggested by historic models. Our analysis has revealed so far at least four horse specimens that can be scientifically dated to prior to 1650 CE (Fig. 3)—long before the Pueblo Revolt of 1680, a date that many historians point to as the earliest likely date for widespread indigenous access to horses. This result is incredibly significant, as it shows that native social and trade networks distributed the horse across the Plains and into the Mississippi region without the direct presence of European traders. This chronology may help us better assess the ecological and environmental impacts that horses had in these new environments.
Fig. 3. Spatial time-slice visualization of modeled dates from pilot study horse specimens, produced using map utility in OxCal. Bubble diameter is proportional to the percent of posterior probability distribution contained within each time slice for a given specimen. The results suggest that a much earlier chronology for the spread and adoption of horses and domestic equids may emerge with future work.
3. Early native horse pastoralists used both European local strategies to herd and control horses in the ancient Mississippi. Isotope studies of horse remains from across the Midwest and the Greater Mississippi show that native horseman supplemented their horses’ diet with both introduced domestic crops (wheat) and native domestic crops (maize) in early history (Fig. 4). Analysis of damage patterns to the teeth of horses from this region shows that some of the earliest domestic horses were ridden with both European style horse equipment (Fig.5) and indigenous, organic horse tack.
Fig. 4. Relative percentage of C4 grasses (including dryland grasses and also domestic crops like wheat) for the central American Plains, from Epstein et al. 1997, as compared to the isotope values of horse remains from archaeological sites across the Mississippi and Great Plains studied so far. Values above or below the grey reference data, highlighted by the black arrows, suggest dietary changes beyond those caused by variation in local grasses— possible instances of maize (C4) or wheat (C3) foddering worthy of future investigation.
Fig. 5. Left: Bit wear to anterior second premolar from Kansas River. Center: arthritic damage to the temporomandibular joint, likely linked to the use of a Spanish or European leverage bit (seen right).
These results demonstrate that archaeological study of horse and donkey remains from the Mississippi region is essential to understand the timing and nature of ecological and social changes linked with horse use across this important region. Ongoing study of a large sample of newly collected specimens promises to help expand and rewrite our knowledge of the region, filling in gaps left by fragmentary and biased European historical records.
