BIRM-166’s Bogbean Horizon
Archived: 17 September 2026
31,449 BCE is a modern label within volatile Late Pleistocene MIS 3, not a datable Irish year. Derryvree, County Fermanagh, preserves freshwater silts between glacial tills, radiocarbon-calibrated broadly to 34,950–29,750 BCE. Its bogbean, dwarf willow, clubmoss, pollen and insects demonstrate locally ice-free, treeless tundra-like wetlands before later ice advance. Castlepook Cave’s fauna, including mammoth, reindeer, giant deer, predators and small mammals, confirms links with wider Pleistocene Europe. A possibly cut-marked reindeer bone may indicate early human butchery, but remains disputed and cannot prove settlement. No Irish evidence establishes society, institutions or regular exchange. They reveal a living Ice Age landscape.