Ralph A. Clevenger teaches courses in nature photography, stock photography, video production, and undersea photography at Brooks Institute. Clevenger has traveled throughout the world on assignment. His clients include the Monterey Bay Aquarium, The Nature Conservancy, Denali National Park Wilderness Center, the National Park Service, and the National Marine Sanctuary. His publication credits include Audubon, Aqua, Islands, Oceans, Outside, National Geographic magazine, National Geographic Traveler, Popular Photography, National Geographic Books, Smithsonian Books, Sierra Club Books, and many other national and international publications. Ralph’s stock images are represented worldwide by Corbis Images.