DOI: 10.5281/zenodo.4891096
title: Supplementary material for Khaldy et al. 2021; Compass cue integration and its relation to the visual ecology of three tribes of ball-rolling dung beetles

description: <strong>Supplementary Materials:</strong> <strong>Supplementary Table 1: </strong>Absolute angular difference in exit bearing of each manipulation (<em>test: </em>first and second exit bearing; <em>control: </em>first and third exit bearing) for each individual beetle, in each paradigm. <strong>Supplementary Table 2:</strong> Exit angles (0-359°) of ten exit rolls of ten individuals of <em>K. nigroaeneus</em>, <em>G. unicolor </em>and <em>S. fasciculatus, </em>respectively,<em> </em>and the corresponding calculated mean vector length (R) <strong>Supplementary Table 3:</strong> Eye area and step size for <em>K. nigroaeneus, G. unicolor </em>and <em>S. fasciculatus. </em>Figure S1: Response to directional change of compass cues in <em>G. nitens (see figure text below).</em> <em> </em> <strong>Supplementary Figure 1. </strong><strong>Response to directional change of compass cues in <em>Garreta nitens</em>. </strong>Individuals of the diurnal species <em>G. nitens</em> were allowed to roll balls out of a circular arena outdoors under the open sky (<strong>a</strong>), with a polarisation filter placed above the arena with the sun visible (<strong>b, c</strong>) or with a polarisation filter placed above the arena with the sun shielded from view (<strong>d</strong>). Once the beetle had reached the periphery of the arena, it was removed from its dung ball and placed back in the centre alongside its ball. At this time, the apparent position of the sun (<strong>a</strong>, <em>orange arrow</em>) was mirrored by 180°, the apparent e-vector direction was turned by 90° using a polarisation filter (<strong>b-c</strong>, <em>purple arrow</em>) or the position of the sun was changed by 180° while simultaneously turning the apparent e-vector direction by 90° (<strong>d</strong>, <em>orange arrow:</em> sun; <em>purple arrow</em>: polarisation filter). The beetle was then allowed to exit the arena a second time. The absolute angular difference between the first and the second exit angle represent the response to the treatment (<em>test</em>). When the sun was mirrored by 180° (<strong>a</strong>) or the polariser was turned by 90° (<strong>b</strong>), under the open sky, <em>G. unicolor </em>showed no response to this manipulation. Only when the sun was shielded from view would <em>G. unicolor</em> respond significantly to the 90° turn of a polariser by a change in exit bearings approaching 90° (<strong>c</strong>). With the sun mirrored by 180° and the polarisation pattern e-vector turned by 90°, exit bearings for <em>G. unicolor </em>were randomly distributed within the population. Beetles were then allowed to roll a third time, with the manipulated cue(s) moved back to its/their initial position. The mean angular difference between the first and second exit (<em>test</em>), and the first and third exit (<em>control</em>), is represented by a red solid vector and a grey dotted vector, respectively, in each graph. Error bars represents one circular standard deviation.