Figure 1. Experimental arena.

(A) Budgerigars were trained in the laboratory to take off from a perch and land at a Petri dish containing bird seed, placed at the centre of a grey paper disc 41.5 cm in diameter. The disc was placed over a blue background of length 247 cm and width 256 cm. The landings were video-filmed from above and from the side. (B) Illustration of the regions A (yellow), B (blue) and C (light brown) used for the analysis of the spatial distribution of the landings. Details in “Methods”.