Figure 1.

Zebrafish were presented with a companion visible in a corner and, after spatial disorientation in the dark, they were allowed to choose among the four corners when the companion was no longer visible. They reoriented correctly in the geometry only condition (i.e. in a rectangular enclosure in the absence of non-geometric cues). In the landmark only condition (i.e. in a square-shaped enclosure with a single blue wall), they oriented towards the blue wall but were unable to encode the relative positions of the corners using sense (left/right) information. (Online version in colour.)