Is Europe best represented by the bold intellect of Marie Curie, the sprawling imagination of Miguel de Cervantes and the intense musical genius of Ludwig van Beethoven? Or by a migrating stork and a bee-eater, swooping across borderless plains and enjoying freedom of movement across European countries?

The quest to settle this issue has engaged a surprising number of people across the continent, after more than 6 million people voted in a survey within just a week of its launch to determine whether the newly redesigned euro bank notes should depict either cultural figures or birds and waterways.