Nature has presented us with many blueprints for the design and function of animal eyes. The different designs represent adaptations to the light conditions that each animal experiences and the behaviors and needs required for survival of that animal. Understanding these blueprints and the genes required for these designs will reveal fundamental design principles that can inform the development of artificial systems for light detection and vision and will offer information to promote a deeper understanding of our own human eyes. This study will compare and determine the variations in gene activity that permitted a simple change in structure from a fused array of light-catching cells or photoreceptors in the flour beetle eye to an open array of photoreceptor cells in the eyes of fruit flies and mosquito. This change in eye form drastically increased the ability to sense light. Research and training will be provided to students from populations that are underrepresented in science, technology, engineering and mathematical (STEM) disciplines. The project will also provide elementary and high school teachers an opportunity to develop laboratory activities that promote science literacy as well promote scientific literacy in a children's museum.
This project addresses a key question of evolutionary/developmental biology within the context of compound eyes: how are conserved cellular processes modified to produce adaptive transitions within the constraints of constructing a functional tissue? In particular, the individual rhabdomeres of photoreceptors of apposition compound eyes are either organized in a "fused" rhabdom (e.g. ommatidia of Tribolium) or "open" rhabdom (e.g. ommatidia of Drosophila) configuration. In apposition compound eyes, the presence of an open rhabdom combined with the principle of neural superposition enabled an increase in light sensitivity without a commensurate loss of visual acuity, and as such allowed some species to diversify into niches characterized by low light availability. The objectives of this grant are designed to continue to identify the different cellular and molecular mechanisms responsible for this evolutionary change and test whether similar mechanisms are responsible for the convergent evolution of open rhabdoms. Secondarily, our work in Tribolium will also expand the genetic amenability of this model organism, and thus permit greater access and usefulness across research disciplines. Overall, insights provided by the research will reveal potentially novel as well as shared cellular mechanisms that lead to adaptive organizations and to the tremendous morphological diversity observed in visual systems.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
