Researchers have found that elephants have hundreds of distinct signals and gestures. Elephant biologist and conservationist Joyce Poole and her husband, Petter Granli, founders of ElephantVoices , developed an online database of those signals, as described in an article on National Geographic's A Voice for Elephants blog . Among the categories of signals and gestures is "play." Watch a video of elephants at play as Joyce Poole narrates and explains their behavior.