South African ball-rolling dung beetles exhibit a unique orientation behavior to avoid competition for food: after forming a piece of dung into a ball, they efficiently escape with it from the dung pile along a straight-line path. To keep track of their heading, these animals use celestial cues, such as the sun, as an orientation reference. Here we show that wind can also be used as a guiding cue for the ball-rolling beetles. We demonstrate that this mechanosensory compass cue is only used when skylight cues are difficult to read, i.e., when the sun is close to the zenith. This raises the question of how the beetles combine multimodal orientation input to obtain a robust heading estimate. To study this, we performed behavioral experiments in a tightly controlled indoor arena. This revealed that the beetles register directional information provided by the sun and the wind and can use them in a weighted manner. Moreover, the directional information can be transferred between these 2 sensory modalities, suggesting that they are combined in the spatial memory network in the beetle’s brain. This flexible use of compass cue preferences relative to the prevailing visual and mechanosensory scenery provides a simple, yet effective, mechanism for enabling precise compass orientation at any time of the day.

Lateralized behaviours are widespread in both vertebrates and invertebrates, suggesting that lateralization is advantageous. Yet evidence demonstrating proximate or ultimate advantages remains scarce, particularly in invertebrates or in species with individual-level lateralization. Desert locusts (Schistocerca gregaria) are biased in the forelimb they use to perform targeted reaching across a gap. The forelimb and strength of this bias differed among individuals, indicative of individual-level lateralization. Here we show that strongly biased locusts perform better during gap-crossing, making fewer errors with their preferred forelimb. The number of targeting errors locusts make negatively correlates with the strength of forelimb lateralization. This provides evidence that stronger lateralization confers an advantage in terms of improved motor control in an invertebrate with individual-level lateralization.

Despite evidence of asymmetries in insect sensory perception and motor control, there is no direct evidence for functional left-right asymmetry in their limb control--handedness--equivalent to that of vertebrates such as humans (reviewed in [1,2]). Here, we show that locusts are biased in the forelimb they use to reach across a gap in the substrate upon which they are walking. The strength of this bias differed among individuals, as did the forelimb, some locusts favouring their right forelimb more often, others their left. In contrast, the locusts' forelimb movements immediately prior to reaching, or whilst walking, were unbiased. This pattern was repeated when the gap was replaced with a glass platform; forelimb use was unbiased when stepping onto the glass surface but biased when stepping onto the other side. Thus, locusts show handedness during targeted forelimb placement, but not whilst walking, the switch initiated by visual inputs. This handedness is context-dependent and is expressed by individuals rather than at the population level.

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