Center for Is og Klima > Arrangementfolder > Engelske arrangementer > Ice Core Genetics

Ice Core Genetics applied on basal ice from Camp Century ice core and Dry Valley glacier ice

- a rehearsal on thesis presentation

by Astrid Schmidt, CIC

Reconstructions of palaeo-ecosystems have traditionally been approached by analysis of pollen and macrofossil remains from geological layers representing the past environments. These traditional methods are very specific in terms of the taxonomic level to which the fossil material can be assigned and can provide climatic and ecological details from the composition of the detected remains. However, the methods are inadequate when accessibility to sample material is limited or when the past biota did not leave a representative fossil record behind. Ancient DNA (aDNA) methods have the potential to detect past biodiversity in areas where sediments have adsorbed genetic degraded material from dead organisms and preserved it in a frozen state. Polar areas with low temperatures and dry climates offer optimal DNA and fossil preservation condition but access have only been possible on the margins of the ice sheets that cover Greenland and Antarctica. Amplification of ancient genetic material from ice cores can therefore contribute with details on past ecological characteristics, biodiversity and age of the periods where the ice sheets retreated in response to warming climates.

Results from the thesis verified the existence of aDNA in the sample material from Camp Century in Northwestern Greenland and from the basal ice in Suess Glacier in the Dry Valleys. The results could be used to deduce mean annual temperature conditions from the composition of the biodiversity detected and to propose minimum ages of when these palaeo-ecosystems existed.