BIOMECHANICAL CONSTRAINTS AND TRADE-OFFS BETWEEN SUGAR AND BLOOD FEEDING IN MOSQUITOES

Although mosquitoes are well known for blood-feeding, only a small number of species actually feed on blood. In many species, both females and males feed solely on sugar solutions with widely varying sugar concentrations. Such mosquitoes do not participate in pathogen transmission to humans, but have essential roles in the ecosystem as pollinators and as food for other animals. In a small number of mosquito species, females have evolved the ability to feed on the blood of animals including mammals and amphibians, whose blood varies in composition and temperature. This project's goal is to understand how mosquitoes cope with the physical and biological challenges associated with ingesting different types of fluids, by comparing and contrasting species that are sugar- and/or blood-feeders. By taking a collaborative and multidisciplinary approach, the research will elucidate mechanisms that enable these particular species to feed on blood, a topic of great medical and economic importance, given that mosquitoes can transmit pathogens responsible for diseases such as malaria and dengue to humans during blood feeding. Overall, the results of this project are expected to expand knowledge in the fields of biomechanics and disease vector biology and to provide preliminary understanding of how blood feeding systems evolved in insects. The project will provide research experiences for three graduate students and several undergraduate students recruited from HBCUs or who are participating in exiting summer research programs. The researchers will continue efforts to engage K-12 students in learning about insects and to disseminate results to the public both locally and internationally. Disease-vector insects such as mosquitoes acquire nutrients from the food they ingest and can, in the process, transmit pathogens responsible for diseases that have tremendous epidemiological impacts on human populations. Surprisingly little is known about the relationship between form and function in the feeding systems of blood-sucking insects, as most research effort has revolved around pathogen transmission. Far less work has been done to understand the physiological and biomechanical characteristics of blood feeding and the adaptations associated with the evolutionary transition from nectar feeding to blood feeding in mosquitoes. In this context, the objective of this proposal is to understand and elucidate the biomechanical mechanisms and challenges associated with feeding on both blood and sugar solutions, providing a new functional basis for understanding how blood feeding evolved. In this project, the research team will test the hypothesis that mosquitoes have developed sex- and species-specific mechanisms to deal with the challenges inherent to ingesting fluids across the broad range of properties exhibited by nectar and blood from different sources. A multidisciplinary, convergent approach employing complementary experimental and computational methods will be used to determine the biomechanical constraints and trade-offs underlying differences in fluid ingestion in mosquitoes. Results will be disseminated in print, via internet resources like YouTube, and in public presentations. The researchers will develop educational resources for K-12 students and participate in existing programs that bring middle and high school students from under-represented groups to the university to engage in hands-on science activities and workshops. 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.