Jonathan Alderfer is a widely published author and field guide illustrator. He is co-author, with Jon L. Dunn, of National Geographic Birding Essentials, co-editor of National Geographic Field Guide to the Birds of North America, 5th edition, and editor of National Geographic Complete Birds of North America. He is also chief consultant for the National Geographic Birding program. Jon L. Dunn is an expert on the identification and distribution of North American birds. Dunn is a co-author of National Geographic Birding Essentials. He served as chief consultant for four previous editions of National Geographic Field Guide to the Birds of North America, and as editor of the fifth.