On a hot Chilean beach in January 1835 the twenty-four year-old Darwin picked up a conch shell covered in tiny holes, like lace which he slipped into his pocket. Under the microscope in his Beagle cabin, with one of the holes illuminated by candlelight, he saw the squatter, the tiny cream-coloured curled creature that had dug the hole. What manner of beast was it? It looked for all the world like a barnacle, but Darwin knew that, according to the zoology text books, barnacles secrete their shelly homes; they don't dig them. He teased out the creature from the base of the hole with a pin and then under the microscope examined its beautiful and complex anatomy. He checked the zoology books in the ship's library just to be sure. It was indeed a barnacle anatomically, although there were unaccountable deviations from the barnacle's archetypal norms. He didn't know it at this point, but this barnacle, soon to be nicknamed Mr Arthrobalanus, would not be finished with him for a further twenty years. This was an encounter on a beach with a creature too small to see with the naked eye that would lead to eight years of meticulous dissection and observation of every known barnacle - fossile and living - in the world and to four published volumes with hundreds of pages of analysis. (from 'Darwin and the Barnacle' by Rebecca Stott)