It is 1846. Darwin is poised to publish "The Origin of the Species" and blow the scientific world apart. But one small creature makes him hesitate. First, he decides to solve the riddle of a tiny barnacle the picked up on teh shores of southern Chile, the last of his Beagle specimens. The investigation takes eight years and tests his theory to the limit. "Darwin and the Barnacle" is the fascinating story of how genius sometimes proceeds through indirection - and how one small item of curiosity contributed to history's most spectacular scientific breakthrough.