The SeaWorld Education Department maintains this useful learning resource on Killer Whales. Organized into a dozen categories, the site covers Scientific Classification, Habitat and Distribution, Physical Characteristics, Senses, Adaptations for an Aquatic Environment, Behavior, Diet and Eating Habits, Reproduction, Birth and Care of Young, Communication and Echolocation, and Longevity and Causes of Death. In addition, there is a listing of Books for Young Readers, a Bibliography, a hyperlinked Index/ Glossary, and classroom activities for grades 4-8. Although the sections contain mainly text, there are several crisp black-and-white photographic images, color illustrations, film clips (QuickTime), and a live cam recording of killer whales in San Diego's SeaWorld. For curious beginners or anyone wanting to learn a lot about killer whales, this is a fine baseline resource.