The Burgess Shale was one of the most famous and important fossil localities known at the end of the twentieth century. Charles Walcott, who at the time was secretary of the Smithsonian Institution, discovered this fossil-rich rock bed in 1909 while exploring the Canadian Rockies of British Columbia. The Burgess Shale, which is now a part of Yolo National Park, is famous for the wide diversity of fossils of soft-bodied marine animals that are embedded in it. These fossils are approximately 530 million years old, and represent an array of life-forms present during the early-middle years of the Cambrian period (545-495 million years ago). The area originally quarried by Walcott is surprisingly small given the array of unique animal forms found in it. His initial survey covered an area that is only 10 feet tall and 200 feet long, the length of one city...