Virginia is arguably the birthplace of ornithology in North America. Captain John Smith and naturalist Mark Catesby were among the early describers of Virginia's common birds. David Johnston's book, however, begins by taking the reader back to the Tertiary period, some 65 million years ago, with Storrs Olson's description of fossils from tidewater Virginia. John Guilday, studying bone deposits in mountain caves, identified 80 species of birds, including Rock Ptarmigan and Spruce Grouse, from a time when Virginia's climate differed greatly from that of today. Archaeological studies and accounts of aboriginals in the 17th century complete Chapter 1.