THE UTILITY OF NON-POLLEN PALYNOMORPHS AS PALEOENVIRONMENTAL PROXIES IN THE SOUTHEASTERN UNITED STATES

Non-pollen palynomorphs (such as fungal spores) are often overlooked in traditional palynological analyses, but can be indicators of various environmental changes such as fluctuations in plant and animal communities, erosion and fire events. This paper demonstrates the utility of fungal spores as paleoenvironmental proxies at two submerged sites in the Southeastern United States: Page-Ladson, Florida and White Pond, South Carolina. Two cores from the Page-Ladson archaeological site, Florida were analyzed for pollen and the dung fungus Sporormiella. The disappearance of Sporormiella, a well-established proxy for large herbivore abundance, by ~12.7k cal BP is consistent with the timing of the Rancholabrean termination elsewhere in North America. However, a resurgence of Sporormiella between ~10.75-10.2k cal BP suggests an Early Holocene incursion of extant megaherbivores (e.g., bison). Pollen evidence from the site also reflects dramatic vegetation changes, which are likely a response to both changing climate and fluctuating herbivore populations. These results are consistent with the hypothesis that spring-fed ponds in sinkholes, such as Page-Ladson, were natural focal points for fauna and early hunter-gatherer populations in a significantly more arid terminal Pleistocene environment. White Pond, South Carolina is a small pond located at the intersection of the Coastal Plain and the Piedmont in the southeastern United States. In sediments dating older than 13.25k cal BP, dung fungi concentrations are consistently high, indicating a possible abundance of large herbivores around the site at this time. In sediments dated to ~13,25-12.7k, dung fungi concentrations remain moderate to high. Toward the end of this zone, total spore concentration declines, primarily as a result of declining dung fungi Coniochaeta and Podospora. This may reflect a decline in herbivore populations at the onset of the Younger Dryas. In sediments dating younger than 12.7k cal BP, total spore concentration is low which is consistent with the timing of megafaunal extinction elsewhere in North America. These results demonstrate the utility of fungal spores as proxies for paleoenvironmental change and contextualize inferred changes in human behavior at the onset of the Holocene.