When it's time to migrate, how do birds find north? The going theory is that some avians can literally see the magnetic fields. Talk about a birds-eye view. However, a recent experiment shows that ability is hampered unless the creature in question has good vision in the right eye. Outfitting a variety of European robins with goggles frosted on one side and clear on the other -- but transmitting the same amount of light to both eyes -- a team of researchers at Goethe-Universitat in Germany discovered that the birds with blurred vision in their right eye were disoriented, while those with obscured sight on the left headed north without delay. Since we mastered the compass ages ago, there are precious few lessons here for robotic bird builders -- but perhaps once these scientists are satisfied with ocular experiments, they'll get around to figuring out how carrier pigeons manage those cellphone-smuggling return flights.