Polarized light orientation in dim light
A clear full moon night is a million times dimmer than a sunny day, but despite these drastic differences in light intensities, South African dung beetles of the genus Scarabaeus navigate with the same precision at night and day. In this project, we aim to characterize the general structure of the celestial analyzer in the eye of a nocturnal navigator and identify the visual adaptations and the neuronal network that supports celestial orientation over a range of 8 orders of magnitude of light intensity from day to night. What are the adaptations for high sensitivity in the nocturnal compass system? Are nocturnal navigators more sensitive to degradations in the celestial polarization signal? Does nocturnal navigators trade precision or speed for increased sensitivity?
We seek the answer to these and many other questions through behavioral studies in the field an in the lab, and by anatomical, morphological and electrophysiological investigations of the eye and the brain of the insects.