Book excerpt: This RSPB-endorsed book answers all those burning questions about birds that beginners and experts alike may ask themselves as they go about their birding. How do ducks keep their feet from freezing in winter? Why don't swallows stay in Africa? Are birds really dinosaurs, or were dinosaurs really birds? And do birds have knees? Taking a 'questions and answers' approach, each specific question leads to an answer which expands the theme under discussion, so that all aspects of bird life and the hobby of birding are covered. The scientifically rigorous answers together form an impressive and fascinating body of bird-related information. This highly readable book will intrigue anyone with an interest in birds.