Oldest DNA samples found on Greenland
July 2007
The world’s oldest DNA samples have been retrieved from beneath the Greenland ice sheet. Contained in sediments from the bottom of a 2km (1.2 mile) ice core they show that Greenland was covered in a dense conifer forest teeming with flora and fauna less than a million years ago.
Scientists extracted fragments of DNA estimated to be between 450,000 and 900,000 years old. The organisms they stem from include insects such as beetles, butterflies and moths, and pine, yew and alder trees. ‘These correspond to the landscapes we find in eastern Canada and in Swedish forests today,’ says Professor Willerslev of the University of Copenhagen, who led the research team. ‘The yew trees reveal that the temperature during the winter could not have been lower than minus 17C and the presence of other trees shows that summer temperatures were at least 10C.’
It is the oldest authenticated DNA to be recovered from ancient biological material and represents a milestone for scientists trying to reconstruct past habitats eliminated by natural climate change. ‘We’ve learnt that this part of the world was significantly warmer than most people thought,” says Martin Sharp, a glaciologist at the University of Alberta.
source: Steve Connor, Oldest DNA samples found on Greenland, The Independent, 06 July 2007
