Thursday, November 17, 2016, 12:30PM - 1:30PM
SEEC room S225
Molecules in the mud: A sedimentary ancient DNA record of paleovegetation from Baffin Island, Arctic Canada
One expected consequence of a rapidly warming Arctic is a poleward expansion of high-latitude plants. An increase in woody vegetation at high latitudes will both reduce surface albedo and increase atmospheric water vapor, further amplifying warming. Tracking past changes in vegetation in response to temperature fluctuations, particularly during past warm times, has the potential to provide insights into the ecological response to temperature changes and the mode of plant colonization following ice retreat. In this talk, I will present the first lacustrine sedimentary ancient DNA (sedaDNA) record from the Canadian Arctic, in which we reconstruct tundra vegetation growing near a lake on southern Baffin Island over the Holocene. sedaDNA is a novel paleoecological tool that allows for the identification of targeted taxa from the complex mixture of degraded DNA contained in the sediment matrix. Initial results indicate that DNA preservation is excellent in Arctic lake sediments, and sedaDNA-based paleoecological reconstructions offer multiple benefits over traditional palynology. This record precisely constrains the initial establishment of dwarf birch in the catchment and provides a comprehensive picture of tundra ecosystem development. When paired with other paleoclimate proxies from the same core, sedaDNA has the potential to significantly advance our understanding of the complex relationship between climate and vegetation.