Scientists have discovered that the iconic Scots Pine might not be as quintessentially Scottish as its name suggests. They found that trees in the forests of the Scottish Highlands are just as genetically diverse as their ancestors in European forests, meaning they're more closely related than originally thought.

As the ice retreated north at the end of the last Ice Age about 14,000 years ago, pine trees from mainland Europe spread into northern Britain. They eventually colonised vast swathes of Scotland, forming what was called the Caledonian Forest.

But after years of logging and making way for farms, only one per cent of the ancient Caledonian Forest remains.

'We thought that if you removed 99 per cent of the trees, you'd also be taking away a substantial amount of the genetic variation. But we didn't find that at all.'
Dr Stephen Cavers, Centre for Ecology & Hydrology

Scientists feared that such a huge loss of trees would also translate into a loss of genetic diversity, which could pose problems for the Scots Pine when faced with changes in the climate. The idea relies on the fact that bigger populations usually have more genetic variation.

'Genetic diversity should make for a stronger and more resilient population,' says Dr Stephen Cavers from the Centre for Ecology & Hydrology, who led the study which is published in Heredity.

Cavers and researchers from the University of Edinburgh, the Macaulay Land Use Research Institute and the Polish Academy of Sciences decided to find out if their assumptions about genetic variability in Scots Pines were right. They tested for similarities in key genes in trees from 21 forests across Scotland, and compared them with trees from all over Europe to see how distinctive the Scottish trees are.

'We thought that if you removed 99 per cent of the trees, you'd also be taking away a substantial amount of the genetic variation. But we didn't find that at all,' says Cavers.

Not only did they find that Scottish Scots Pine forests are just as genetically diverse as their European cousins, they also found that forests in the east of the country are slightly different to those in the west.

'This suggests the trees could have come from two different places,' explains Cavers.