Mechanisms of celestial navigation in Drosophila

California Institute Of Technology, Pasadena CA

Investigators

Abstract

Like ancient mariners, many flying animals have the ability to navigate long distances across the globe using cues from the earth and sky. One particularly reliable feature of the sky that animals can use as a compass is the pattern by which light from the sun is polarized as it scatters in the atmosphere. This project will study how animals navigate using polarized skylight, by exploiting state-of-the art genetic and physiological approaches that are available in the common fruit fly, Drosophila melanogaster. The results will provide insight into the general question of how circuits in the brain can make accurate calculations that guide locomotion and other motor actions. Simplified, inexpensive versions of the experimental devices used in the proposed studies will be developed for use in education and outreach. The findings will also benefit ongoing efforts to engineer small, energy-efficient autonomous air vehicles that can perform useful missions for civilian and military applications without the need of GPS. Using this experimentally powerful genetic model organism, it will be possible to determine how specialized cells and circuits in the brain detect and process polarized light and use it as a compass reference for navigation. The project will make use of custom-built flight simulators, in which animals navigate under an artificial sky that may be experimentally manipulated. The research will also employ recently developed techniques of two-photon calcium imaging in freely flying subjects for measuring the activity of cells within relevant neural circuits of the brain as navigation tasks are being performed, a level of analysis not previously achieved. Results from these studies will be disseminated through publications in peer-reviewed journals, and through presentations at scientific conferences.