Some Scandinavian trees survived the last Ice Age, challenging a widely held notion that they were killed off by the huge ice sheet that covered the region.
Modern trees in Scandinavia were thought to descend from species that migrated north when the ice melted 9,000 years ago.
But research suggests some conifers survived on mountain peaks that protruded from the enormous ice sheet, on islands and in coastal areas.
The work appears in Science journal.
“Our results demonstrate that not all the Scandinavian conifer trees have the same recent ancestors, as we once believed,” said Prof Eske Willerslev from the Centre for GeoGenetics, University of Copenhagen.
“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.
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