Explore every Emerald Archives article connected with Birm-166.
31690–31681 BCE
Radiocarbon results of this antiquity are not calendar dates. Birm-166, taken from Derryvree organic silts, produced a determination of 30,500 radiocarbon years before present, with a substantial uncertainty of +1,170 and −1,030 years. Calibration is necessary because atmospheric carbon-14 has varied through time. Later scholarship places the result broadly within c. 36,900–31,700 calibrated years before present. That broad span includes the modern reference-point of 31,690 BCE, but it emphatically does not turn the Derryvree deposits into a record of one year, one generation, or even one unbroken century.
31700–31691 BCE
31,698 BCE is a retrospective label, not a recoverable Irish year. Derryvree, County Fermanagh, provides calibrated evidence for ice-free conditions between roughly 36,900 and 31,700 years before present, preserved as freshwater organic silts between tills. Mosses, sedges, bogbean and insects indicate a cold, open periglacial wetland, amid climatically unstable MIS 3 conditions. Cave calcite and deposits elsewhere confirm episodic milder intervals and fluctuating ice. Castlepook Cave's disturbed fauna documents diverse cold-stage mammals, while a possibly cut-marked reindeer bone suggests, but cannot prove, human activity. No settlements, polities or trade are attested. Sediments instead reveal changing wetlands, fauna and advancing ice.
