BlueSearch human history and you'll quickly conclude that we've been enamoured of blue at least since the pharaohs. So, it's startling to turn to the realms of nature and discover that "true" blue is truly rare. From the rainforest's morpho butterfly to the blue jay flitting past your window, few living things are blue and most that appear so are performing sleight of hand with physics or chemistry. Cornflowers use the pigment found in red roses to