Berlin is a metropolis, a big city with international flair and at the same time the habitat of countless raccoons, foxes, bats, squirrels, hedgehogs and beavers. There is at least one pair of birds for every human inhabitant of Berlin, and nowhere else are there so many sparrows and nightingales. Swarms of bees harvest honey from almost half a million city trees, a badger roams through a backyard, and praying mantises lurk for prey in railroad tracks.