Fig. 7. Speed of reaching the goal after removal of prominent landmarks (experiment 3a) and after removal of local cues (experiment 3b) (means ± S.E.M., N=15. Removal of prominent landmarks impaired the birds when they used the right eye. ^**Right-eye only condition in experiment 3a was significantly different from all other monocular conditions in 3a and 3b (P<0.01). There was no difference between the other monocular conditions. See text for details.