Do Pigeons determine Latitudinal Displacement from the Sun's Altitude?

ONE of the principal hypotheses of pigeon navigation is that of Matthews 1–3 , and although many experiments seem to disprove it, Matthews himself has continued to defend his hypothesis 4 . He proposes that a bird observes the Sun's movement at the release site and compares its extrapolated path with the Sun's path it remembers from its home location. The difference in the noon altitude of the Sun at the two sites indicates the bird's latitudinal displacement, and the difference in local Sun time at the two sites indicates the longitudinal placement.