Fig. 1. Experimental set-up. Ants reached a feeder (F) in three different conditions: by travelling 6 m, 12 m, 20 m and 35 m from the nest (N) in an open field (A); by walking in an L-shaped channel (thick lines), where experimental ants travelled either 6 m (B) or 3 m (C) on the second leg and the control ants travelled only the first leg of the journey; and by travelling in linear outbound channels of 6 m and 12 m (D). In A–C, ants that picked up a cookie crumb were displaced to the test field where their paths were recorded. In D, ants that picked up a cookie crumb were captured and displaced to the end of the 30 m test channel, where their distance estimate was measured. Thin lines with arrows show the displacement of ants from the feeder either to a release point (R) in the test field or to the test channel. Note: figures not to scale.