The Birds of America
Audubon's influence on ornithology and natural history was far reaching. Nearly all later ornithological works were inspired by his artistry and high standards. Charles Darwin quoted Audubon three times in "On the Origin of Species" and also in later works. Despite some errors in field observations, he made a significant contribution to the understanding of bird anatomy and behavior through his field notes. "The Birds of America" is still considered one of the greatest examples of book art. Audubon discovered 25 new species and 12 new subspecies.