Ancient DNA finds Greenland's past a land of trees and butterflies

William Atkins
Friday, 06 July 2007 04:36

Science - Climate

So what happened?

Eske Willerslev, from the Center for Ancient Genetics, at the University of Copenhagen (Denmark), and other team members used samples of DNA (deoxyribonucleic acid) taken from one mile under the Greenland ice cap, in an area known as Dye 3.

The analysis of the DNA recovered deep under the ice of Greenland showed the genetic material from such plants as spruce, pine, and yew trees, and such insects as spiders, butterflies, and flies.

Such genetic materials from organisms living during this ancient time in Earth's past show that the southern part of Greenland was about 50 degrees Fahrenheit (10 degrees Celsius) in the summer months and around 1 degree Fahrenheit (-17 degrees Celsius) during the winter. Willerslev describes such an environment as what now exists in eastern Canada, and one very conducive to trees and insects.

Less ice on Greenland also means that the water levels were three to six feet higher than today.

Only the coastal areas of Greenland, today, are not covered with ice. With about a total area of 2.1 million kilometers (800,000 square miles), the Greenland ice sheet covers about 80% of Greenland’s area. All the populated areas are located on the coast of Greenland, with most of its peoples on the western coast.

Willerslev’s team was able to eliminate the use of fossils and only use DNA samples in order to recreate an environment that existed in the Earth’s distant past. The DNA found underneath the Greenland ice mass is considered the oldest DNA so far uncovered on the Earth.

With about 10% of the Earth today covered with thick glaciers and ice sheets, this technique has interesting possibilities for other yet-explored frozen areas of the world.

The results of Willerslev’s team appear in the July 6, 2007 issue of the journal Science (volume 317, number 5834, pages 111-114). Its title is “Ancient Biomolecules from Deep Ice Cores Reveal a Forested Southern Greenland”.