If you were wondering why one might pay $8 million for a book, well, Cornell University Lab of Ornithology offers some clues. Their library owns one of the twelve remaining original copies of Audubon's Birds of America. A different original just sold at Christie's fetching the third largest sum ever for a book. The Cornell copy was brought out for examination by one of the university's art professors, specifically to view some of the best remaining images of America's extinct species. The viewing was filmed in this fascinating short documentary below. You can read more about the book and the artist's project at the Round Robin.