How Homing Pigeons Navigate

goombah99 writes "Over the years there has been much research and speculation on how homing pigeons navigate. The assumption has been they need some novel sensory mechanism to give them north-south orientation information. Theories included magnetic field sensitivty and polarized light sensitivity, other possibilies include analysing the motion of the sun. But British researchers appear to have cracked the case: they follow roads and landmarks and don't require special senses. Birds, it seems, actually follow the longer as-the-dog-walks path of the road, even circling over round-abouts rather than the straight 'as-the-bird-flies' path one would expect if they used absolute position sensing."