Insect fossils: Late Neogene/early Quaternary records

Abstract

During the past 40 years, Quaternary insect paleontologists working in the Arctic have studied rare deposits of fossil insects that date back millions of years. Some of these fossils are as old as the Late Miocene. The fossils have been preserved mostly in permafrost environments, and their state of preservation is often exceptional. The vast majority of identifiable beetle specimens match modern, extant species. This morphological constancy through time appears to reflect the constancy of physiological adaptations, as well. The latter aspect is demonstrated indirectly through the ecological compatibility of species found in the ancient fossil assemblages. While most of the species appear to have remained constant, the biological communities in which they lived have shifted dramatically through time. Based on both insect and plant fossil data, Late Neogene environments of the Arctic were substantially warmer than they are today, supporting the growth of coniferous forests, up to the shores of the ancient Arctic Ocean. By about 2 million years ago (mya) or shortly thereafter, the precursors of Arctic tundra communities came into existence in parts of Beringia. Arctic insect faunal diversity declined markedly with the onset of Quaternary glaciations.