The four-colour side of this ruler presents the evolution of life on our planet in detailed pictures. The other side provides information such as the scientific names or the size of depicted plants and animals. A 'snapshot' of Continental Drift and a timeline delineating each era helps the user comprehend the immense time periods over which life evolved on Earth. Users can follow the fascinating adventure of evolution by unfolding this sturdy wooden folding ruler: dinosaurs, when mammals took over, the first insects, how life left the seas, up to the present day.