Scandinavian trees `survived the last Ice Age`
Contrary to widely held perception, a new study has claimed that a number of trees in Scandinavia survived the last Ice Age.
London: Contrary to widely held perception, a new study has claimed that a number of trees in Scandinavia survived the last Ice Age.
It was previously believed that all Scandinavian tress were killed off by the huge ice sheet that covered the region during the last Ice Age. Now, a team at Copenhagen University says some conifers survived on mountain peaks that protruded from the enormous ice sheet, on islands and in coastal areas.
"Our results demonstrate that not all the Scandinavian conifer trees have the same recent ancestors, as we once believed," the `BBC` quoted as saying Prof Eske Willerslev from the Centre for GeoGenetics, University of Copenhagen.
He added: "There were groups of spruce and pine that survived the harsh climate in small ice-free pockets, or in refuges, as we call them, for tens of thousands of years, and then were able to spread once the ice retreated.
"Other spruce and pine trees have their origins in the southern and eastern ice-free areas of Europe. Therefore, one can now refer to `original` and later naturally `introduced` Scandinavian conifer species."
Researchers have based their findings on analysis of the DNA of modern spruce - which clearly portrays two Scandinavian types - and by examining the composition of pine and spruce DNA in sediments from lake-core samples.
"One hypothesis is that trees were able to survive on the top of nunataks, the exposed ridges or peaks of mountains protruding from glacial cover, or in more sheltered areas close to the coast where proximity to the temperate conditions of the Atlantic Ocean favoured survival," said Laura Parducci, at the University of Uppsala, a member of the team.
She wrote in the `Science` journal: "These areas must have provided sites for roots to anchor and trees to grow in the challenging climate."