You Are Here by Colin Ellard Page B

would expect path integration based on inertial guidance to be less accurate in mammals than it is in ants, and this is an expectation that has been confirmed in every case so far. But path integration can be carried out with other senses.
    When furry creatures try to navigate in the lightless confines of a psychology experiment, they can be made to lose their way like human beings stumbling through a dark house during a power failure. It may take longer for them to stumble, but sooner or later, with enough twists and turns, integration drift will take its toll. A brief flash of light, though, like a bolt of lightning seen through a bedroom window, can reset our sense of position and turn integration drift back to zero. The details of how path integration works in darkness, and how brief visual “fixes” can reverse the accumulating errors of integration drift, have been worked out in experiments carried out with hamsters (their nice habit of stuffing food into cheek pouches and carrying it home to store in a larder makes them an excellent species for studying such problems). The main finding from these studies is that, provided there is not a great discrepancy between where a visual fix tells us we are and the location indicated by our inertial guidance system, a brief glimpse will wipe clean the slate, and re-zero integration drift. If the visual fix gives a surprising result, then it might be ignored. 10
    For example, imagine that you’ve arrived at your cottage, late at night, and need to find the main power switch to turn on thelights. You have a rough idea of which way to go from the front door, and you set off with your hands in front of you, feeling your way through darkness. A car drives past on a nearby road, and the sweep of headlights through the window provides you with a momentary visual fix. If the fix shows that you are walking at a slight angle to the target, you will correct your course. But if the flash of light suggests that you are walking in the completely wrong direction—back toward the door rather than toward the far wall where the power switch is located—you might be prone to disbelieve your eyes, wondering if the poor light has caused some kind of illusion.
WHAT’S GOOD FOR THE GOOSE MAY NOT BE GOOD FOR US
    In a classic study of animal navigation, Ursula von St. Paul took a group of domestic geese on a country ride in a small covered cart. The ride began at their home and proceeded through a series of complicated switchback turns along narrow lanes through varying types of terrain. For some segments of the ride, von St. Paul covered the cart with a blanket so that the geese were not able to see anything. For other segments, the cart was uncovered so that the geese could see the sights as they rode. At the conclusion of the tour, von St. Paul took the geese out of the wagon and released them. Would they be able to find their way home?
    The key finding in this experiment was that the geese picked a homeward route as if the only movements they had made had been those undertaken while the cart was uncovered. While carried around in the cart, the geese would have had very little access to inertial guidance because their vestibular systems would not function well while they traveled passively in such an unnatural conveyance. But the most interesting aspect of this finding was that the geese apparently
were
able to path integrate using the flow of visual motion that they received while the cart was uncovered, and this is avery different form of path integration from that using the vestibular senses for inertial guidance. 11
    Although this experiment showed clearly that path integration works well using vision, surprisingly few studies have aimed at determining how precisely this information can be used, especially in mammals. There are a few very intriguing suggestions, though, that geese are not the only animals capable of using path integration in this way.
    In many laboratory studies of spatial