All hail the Christmas tree, a mighty survivor from Mesozoic times | Susannah Lydon

Christmas is full of festive fun for palaeontologists. After all, the Christmas tree in your living room would be at home with the dinosaurs

Palaeontologists have a slightly different take on the world, even at Christmas: Christmas dinner is the ceremonial dissection of an avian dinosaur, and there's no finer joke than a half a billion year old arthropod named after Santa Claus. And so it is with Christmas trees: most people see them as the slightly pagan focal point of their festive decorations. I see this as the one time of year when people actually pay any attention to these mighty survivors from Mesozoic times.

In the UK, the Norway Spruce Picea abies is the traditional species to be festooned with decorations of questionable taste. It exhibits all of the qualities associated with most modern conifers: it is an evergreen woody tree, bearing seeds in cones. It shows monopodial growth (it has one trunk), and strong apical dominance (it grows up more strongly than its branches grow out). It also produces resin, which protects the tree from fungal attack and from pests. It is long-lived (a group of clones in Sweden was carbon-dated at 9550 years old) and is relatively slow-growing: this year's Trafalgar Square Christmas tree is 27 metres tall and was 95 years old when it was felled.