Figure 2. Daily locomotor activity and solar orientation are unaffected by antennal ablation.

. Locomotor activity of intact (a) and antennae ablated animals (b) in L:D 12:12. Black and white bars indicate light and dark respectively. The quantity of activity (recorded simultaneously from a group of twenty individuals in each experiment) is expressed in arbitrary units. Distributions obtained testing: intact (c), antennaless (d) and right antennae black painted (e) animals. 0°, North (zeroed magnetic field); arrow inside the distributions: mean vector and angle (length of mean vectors: 0 to 1 = radius of the circle); black dots: sandhoppers’ directions (each dot corresponds to the direction of one individual); black triangles outside the distributions: landward direction of sandhoppers’ home beach. Sun symbol: solar azimuth at the time of the test. N, sample size. U, Rao’s test values with probability levels (P).