2026/05/28 by James J. Foster, Jacob M. Graving, Keram Pfeiffer · 1 voice
Biochemistry, Genetics and Molecular Biology · Neuroscience · Agricultural and Biological Sciences · #Insect and Arachnid Ecology and Behavior #Neurobiology and Insect Physiology Research #Plant and animal studies
paper · doi:10.21203/rs.3.rs-9827783/v1
Abstract Foraging honeybees rely on a celestial compass to navigate to and from the hive, using the sun’s position as an orientation reference. When the sun is hidden from view,bees can determine its azimuth using skylight patches. The linear polarization, size, and spectrum of askylight patch contribute tothe bee’s estimated position relative to the sun. When the light patch is unpolarized, the relative quantities of green and UV lightmay determine whether it is interpreted as part of the solar or anti-solar sky. Howbees combine this information with the intensity gradient across the sky, present across the wavelength spectrum, remains poorly understood. In order to investigate how intensity affects the interpretation of patches of green and UV light by bees, we presented Western honeybees ( Apis mellifera ) with light spots oflower and higher intensity during the ‘waggle dance’, during which they communicate the direction of a food source relative to the sun. At high intensities, we find that both green and UV light were interpreted as the sun, while for lower intensities we observed an orientation switch between green and UV. We propose that this high-intensity effect may be driven by the combination of beta-band sensitivity of the green photoreceptors to UV light and saturation of the UV photoreceptors. The failure of spectral contrast to influence orientation at high intensities may also be adaptive when the sun is viewed through light cloud that transmits UV.