Scotland has two forms of ancient woodland which are markedly different to much of the UK. They contain rare and unique species of plants and animals. Remaining ancient woodland is thought to have been present since the retreat of the last ice age around 10,000 years ago, when trees were able to persist once more.
Caledonian Pinewood Is found in Northern Scotland in both the Highlands and Cairngorms. As temperatures warmed after the ice age the pinewood forests followed the cooler climate, here it became detached from its species in the rest of Europe at which point the unique Scots Pine evolved. Caledonian forests also contain Birch, Rowan, Aspen, Juniper and Oak. Man has made extinct the larger mammals such as bears, wolves, lynx, elks and wild boars. Remaining are still number of species: deer, beavers, hares, wildcat and red squirrels. Birds found nowhere else in Britain include the Scottish Crossbill and European Crested Tit.