The brain behind straight-line orientation in dung beetles.

For many insects, celestial compass cues play an important role in keeping track of their directional headings. One well-investigated group of celestial orientating insects are the African ball-rolling dung beetles. After finding a dung pile, these insects detach a piece, form it into a ball and roll it away along a straight path while facing backwards. A brain region, termed the central complex, acts as an internal compass that constantly updates the ball-rolling dung beetle about its heading. In this review, we give insights into the compass network behind straight-line orientation in dung beetles and place it in the context of the orientation mechanisms and neural networks of other insects. We find that the neuronal network behind straight-line orientation in dung beetles has strong similarities to the ones described in path-integrating and migrating insects, with the central complex being the key control point for this behavior. We conclude that, despite substantial differences in behavior and navigational challenges, dung beetles encode compass information in a similar way to other insects.