Beetle records: Late Pleistocene of North America

Research on late Pleistocene North American beetle faunas began in eastern North America and has since spread throughout much of the continent, from the Arctic to the desert regions of northern Mexico. This research has documented large-scale, rapid climatic changes in nearly all study regions except southern California. During the mid-Wisconsin interstadial, beetle assemblages have demonstrated oscillating warming and cooling events that coincide with climatic patterns inferred from oxygen isotope records in Greenland ice cores. The pace and amplitude of such changes have often gone undetected in pollen records. Climatic amelioration following the Last Glacial Maximum began by 17 ka. The Younger Dryas oscillation has thus far only been detected in beetle faunas from Maritime Canada and Arctic Alaska. Just as in Europe, North American beetles appear to have responded to the vagaries of Pleistocene climates by shifting their distributions in order to stay within climatic conditions to which they are best adapted. Thus, the Pleistocene beetle fauna of North America remains extant today, albeit living in different regions.