Two sperm whales, members of a social unit named "The Group of Seven," begin a dive together in the deep waters close to Dominica, West Indies. Courtesy of Luke Rendell/Whitehead Lab Dominica Sperm Whale Project hide caption

itoggle caption Courtesy of Luke Rendell/Whitehead Lab Dominica Sperm Whale Project

"Anytime you're in the wild with a beautiful animal you're going to feel good," says Susan Casey, author of Voices in the Ocean: A Journey into the Wild and Haunting World of Dolphins. Penguin Random House hide caption

itoggle caption Penguin Random House

Some researchers have begun to question the notion that dolphins are the super-intelligent creatures they've been made out to be. Pavel Golovkin/AP hide caption

itoggle caption Pavel Golovkin/AP

Demonstrators at a rally in Tokyo on August 31 protest against the start of Japan's annual dolphin hunt in Taiji. Yoshikazu Tsuno/AFP/Getty Images hide caption

itoggle caption Yoshikazu Tsuno/AFP/Getty Images

An elephant at the Emmen, Netherlands, zoo stands at the edge of a ditch in 2009, a day after another elephant fell into the ditch and died. Olaf Kraak/AFP/Getty Images hide caption

itoggle caption Olaf Kraak/AFP/Getty Images