Over 35,000 copies sold As a naturalist managing the field studies program at the California Academy of Sciences, John Muir Laws noticed that novice birders often distinguish birds by color and size rather than species. This inspired him to create Sierra Birds: A Hiker's Guide , a unique book that assumes no prior birding knowledge on the part of the reader. Color-coded keys eliminate the time-consuming frustration of thumbing randomly through a guide, and a cross-index is also included for more advanced birders. All this in a format that is simply organized, lightweight, and small enough to tuck inside a pocket. A first-rate naturalist, Laws is also an accomplished artist. His illustrations are lively, colorful, and accurate, and drawn to represent species in the manner in which one generally sees them in the field.