A dolphin handler makes the signal for "together" with her hands, followed by "create". The two trained dolphins disappear underwater, exchange sounds and then emerge, flip on to their backs and lift their tails. They have devised a new trick of their own and performed it in tandem, just as requested. "It doesn't prove that there's language," says Aza Raskin. "But it certainly makes a lot of sense that, if they had access to a rich, symbolic way of communicating, that would make this task much easier."

To see the world through the eyes of a 40-ton polar whale it helps to use a little bug. At least that's what this satellite tracking tag resembles. We're crammed into an inflatable black rubber zodiac on a blustery day in Antarctica's Gerlache Strait, puttering toward a motionless humpback whale. A fist-sized camera with gangly grasshopper-like antennae and suction cup feet sits on a pole resting on scientist Ari Friedlaender's shoulders. Towering icebergs and glacier-draped mountains rise around us.