PALYNOLOGY OF PLEISTOCENE AND HOLOCENE SEDIMENT CORE BBL 3, BIG BONE LICK, KENTUCKY

The discovery of vertebrate remains at Big Bone Lick along the Ohio River in 1739 and their subsequent study in France and England in the late 1740’s-1760’s marked the beginning of vertebrate paleontology in North America. Associated plant remains have been known from these deposits since expeditions in the 1950’s, however, until recently, no meaningful palynoflora has been documented. The initial study of eight samples obtained in 2012 produced an abundant and diverse palynofloral record that spans the upper Pleistocene to middle Holocene. Here we present the first palynological study of the BBL 3 core, obtained by the Kentucky Geological Survey in July 2004. The core was described, slabbed, sub-sampled for geochemistry on a 20-cm spacing in 2004. 33 new subsamples were obtained, following the original sampling pattern. They were disaggregated in sodium hexametaphosphate; clays removed using short-hard spins and larger silica grains and heavy minerals removed via heavy density separation with LST® at a specific gravity of 2.0. The residues are charcoal and palynomorph-rich; non-pollen palynomorphs (NPPs) are especially abundant. Of note, the plant pollen and spores recovered do not match the documented mesobotany for the site. Tulip poplar (Liriodendron tulipifera), Copperleaf (Acalypha sp.), grape (Vitis sp.), and Pinks (Silene sp.) pollen are absent, as are lichen spores. This likely represents preservational bias and flooding of local signals by transported pollen. The NPP flora is dominated by fungal remains. These include mutualistic (mycorrhizal), parasitic, and saprophytic taxa, including known dung fungi. The mycorrhizal fungal flora is dominated by spores of ecto- and ericoid mycorrhizal fungi. Diverse dung fungi point toward the presence of a variety of herbivores and carnivores already known from their bones, but also toward the presence of geese, the bones of which are not preserved at Big Bone Lick.