
Long-distance navigation is among the most impressive behaviors animal perform. Elucidating the neural basis of distinct types of navigation is a central challenge in neuroscience, as doing so will likely reveal general principles of how the brain stores and recalls memories, how it converts sensation to movement, and how it learns through experience. My research addresses these issues by examining how the fruit fly (Drosophila melanogaster) uses cues from the sky to maintain a straight heading in flight. Although the fruit fly is not a widely heralded navigator, classic release and recapture studies suggest that it can disperse over 10km in a single day, equivalent to 2x106 body lengths. I will present evidence that flies accomplish such dispersal by maintaining a constant heading relative to the pattern of polarized light in the sky. By using a virtual reality flight simulator to manipulate polarized light cues as flies perform fictive dispersal trajectories, I find that individual flies maintain a consistent heading relative to the axis of polarized light but that the value of the heading is highly variable across individuals. This variability contrasts markedly with flies' highly stereotyped, reflex-like responses to other visual cues. I find that flies' preference for a given heading develops gradually, suggesting that heading preference gradually consolidates over an initially random direction through a self-reinforcing process. Additionally, I will present preliminary data describing how polarized light is detected and processed by the fly brain.

Long-distance navigation is among the most impressive behaviors animal perform. Elucidating the neural basis of distinct types of navigation is a central challenge in neuroscience, as doing so will likely reveal general principles of how the brain stores and recalls memories, how it converts sensation to movement, and how it learns through experience. My research addresses these issues by examining how the fruit fly (Drosophila melanogaster) uses cues from the sky to maintain a straight heading in flight. Although the fruit fly is not a widely heralded navigator, classic release and recapture studies suggest that it can disperse over 10km in a single day, equivalent to 2x106 body lengths. I will present evidence that flies accomplish such dispersal by maintaining a constant heading relative to the pattern of polarized light in the sky. By using a virtual reality flight simulator to manipulate polarized light cues as flies perform fictive dispersal trajectories, I find that individual flies maintain a consistent heading relative to the axis of polarized light but that the value of the heading is highly variable across individuals. This variability contrasts markedly with flies' highly stereotyped, reflex-like responses to other visual cues. I find that flies' preference for a given heading develops gradually, suggesting that heading preference gradually consolidates over an initially random direction through a self-reinforcing process. Additionally, I will present preliminary data describing how polarized light is detected and processed by the fly brain.