BRC-BIO: Evolutionary drivers of dimorphic sperm function and development

About This Grant

Sperm and egg cells fuse in the process known as fertilization. Each cell contributes half of the genetic material to the offspring produced in the next generation. However, many animals are programmed to produce sperm that lack genetic material and thus run counter to the very definition of a “sperm cell.” It is unknown how sperm cells that lack DNA contribute to the successful production of offspring, but it has become clear that these sperm cells are necessary for reproduction in many species. This research will test one of the leading ideas for why non-fertilizing sperm are produced, revealing fundamental aspects of reproductive biology. It will allow numerous students to engage in the scientific process and build a strong career foundation. Additionally, it will engage the community surrounding the research institution by constructing a limited mobility-accessible butterfly garden, which will be the site of various activities and events. In this research project, the researchers aim to investigate the function of non-fertilizing sperm in Lepidoptera and how sexual conflict may have driven the evolution of non-fertilizing sperm in the Indian Meal moth, Plodia interpunctella. The research team will investigate the role of non-fertilizing sperm by using lines of P. interpunctella that have been experimentally exposed to various levels of reproductive conflict over the course of numerous generations. Sperm of both morphs of selected lines will be assessed for differences in protein composition, morphometric measures, and variation in competitiveness within the female reproductive tract. Together, these analyses will provide functional and comparative insight into the evolution of non-fertilizing sperm. 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.