Serpent Mound, in northern Adams County, Ohio, USA, is one of the most iconic symbols of ancient America and yet there is no widely agreed upon date for the age of its original construction. Some archaeologists consider it to have been built by the Adena culture around 300 bc, while others contend it was built by the Fort Ancient culture around ad 1100. There have been three attempts to obtain radiometric ages for the effigy, but they have yielded inconclusive results. The iconography of the earthwork offers an alternative means of placing the mound in its cultural context. Serpent imagery is abundant in the Fort Ancient culture as well as in the more encompassing Mississippian Ideological Interaction Sphere. Pictographs from Picture Cave in Missouri include a serpent, a humanoid female and a vulvoid in close association. We interpret these elements, in the light of Siouan oral traditions, as First Woman and her consort the Great Serpent. The Picture Cave imagery dates to between ad 950 and 1025. We argue that these same three elements are represented in the original configuration of Serpent Mound and therefore situate its design and original construction in the Early Fort Ancient period.

Salvage excavations of a nearly complete and remarkably well-preserved skeleton of an American mastodont (Mammut americanum) in Licking County, Ohio, yielded a discrete, cylindrical mass of plant material found in association with articulated vertebrae and associated ribs. This material is interpreted as intestinal contents of the mastodont and paleobotanical analyses indicate that the mastodont diet included significant amounts of low, herbaceous vegetation. Enteric bacteria (Enterobacter cloacae), isolated from a sample of this material, are believed to represent survivors or descendants of the intestinal microflora of the mastodont. This is the first report of the isolation of bacteria associated with late Pleistocene megafauna.

Alligator Mound is an animal effigy mound in central Ohio, USA. Since Ephraim Squier and Edwin Davis first recorded and mapped it in 1848, many have speculated regarding its age and meaning, but with remarkably little systematic archaeological investigation. Many scholars have assumed the Hopewell culture (c. 100 BC-AD 400) built the mound, based principally on its proximity to the Newark Earthworks. The Hopewell culture, however, is not known to have built other effigy mounds. Limited excavations in 1999 revealed details of mound stratigraphy and recovered charcoal embedded in mound fill near the base of the mound. This charcoal yielded radiocarbon dates that average between AD 1170 and 1270, suggesting that the Late Prehistoric Fort Ancient culture (c. AD 1000-1550) made the mound. This result coincides with dates obtained for Serpent Mound in southern Ohio and suggests that the construction of effigy mounds in eastern North America was restricted to the Late Woodland and Late Prehistoric traditions. Ethnographic and ethnohistoric analogies suggest that the so-called 'Alligator' might actually represent the Underwater Panther and have served as a shrine for invoking the aid of supernatural powers.