image: This is a dung beetle. view more
Credit: Chris Collingridge (photographer)
A study suggests that South African dung beetles use the wind, in addition to celestial cues, to orient themselves while sequestering food. Dung beetles sequester food by shaping pieces of dung into spheres that are spirited away from competitors in the South African savanna. To hasten their getaway, the beetles scurry in a straight line away from the dung pile, using the sun's position to align themselves as they haul their meal. However, as the midday sun rises in the sky, the beetles' ability to draw positional cues from it wanes. To determine how the beetles maintain their heading despite being deprived of this crucial cue, Basil el Jundi and colleagues tested the beetles' behavior under a series of controlled solar elevations and wind speeds in outdoor and indoor arenas. At high solar elevations, the beetles relied on a wind compass, rather than the sun's position, to find their bearing; the authors monitored wind direction and speed in the beetles' natural habitat and found that the speed peaks when the sun is at its zenith. Wind cues improved the precision of the beetles' orientation. Compared with beetles with intact antennae, beetles whose antennae had been amputated oriented poorly along a given direction, suggesting that the beetles perceive mechanosensory cues using their antennae, likely mediated by a structure called the Johnston organ. Importantly, the beetles were capable of transferring sensory cues between the sun and wind compasses depending on solar elevation, suggesting a composite compass snapshot undergirded by a common neural network for spatial memory. The findings uncover the role of a flexible, multisensory compass for spatial orientation in dung beetles, according to the authors.
Article #19-04308: "Multimodal cue integration in the dung beetle compass," by Marie Dacke et al.
MEDIA CONTACT: Basil el Jundi, University of Würzburg, GERMANY; tel: +49-9313188567, +49-16095437199; email: basil.el-jundi@uni-wuerzburg.de
###
Journal
Proceedings of the National Academy of Sciences