INTELLECTUAL MERIT: Nutrition-triggered phenotypic plasticity is a widespread and evolutionarily primitive adaptive phenomenon. Grasshopper species commonly exhibit phenotypic plasticity in which they convert from sedentary to migratory forms in response to crowding, as in locust outbreaks. While is often hypothesized that dietary cues related to deteriorating environmental conditions might trigger locust swarms, the specific dietary cues that may be triggering this developmental plasticity are unknown. In China, the grasshopper Oedaleus asiaticus is one of two economically important outbreak locusts. Anecdotal information has suggested that there are sedentary (green) and migratory (black) forms of this species, and that prevalence and agricultural damage from the black form of this species is increasing. Preliminary research performed during one month of NSF EAPSI-funded research in 2008 at the Inner Mongolia Grassland Ecosystem Research Station (IMGERS) in northern Chinas Xilin River Basin has strongly suggested that the black form is a migratory phenotype of O. asiaticus, and that migratory capacity can be interactively influenced by density and diet (specifically the carbon to nitrogen, C:N ratio). In this research, the density and diet of O. asiaticus will be manipulated in the lab and field, and morphological, physiological and behavioral responses of developing will be made, in order to test the hypothesis that dietary C:N ratio is a key parameter influencing formation of the economically damaging migratory phenotype of this grasshopper. In addition, this research will test whether overgrazing promotes formation of migratory phenotypes in O. asiaticus via effects on vegetation structure and chemical composition. BROADER IMPACTS: During an outbreak year, swarming grasshoppers (locusts) can populate 11 million square miles of land worldwide, negatively affecting more than 60 countries and the livelihood of 1 out of every 10 people. Global climate change is predicted to increase precipitation variability and thus exacerbate locust outbreaks. This research will provide critical data necessary to understand and potentially prevent disastrous locust swarms. INTERNATIONAL COLLABORATION: This research will establish long-term international research ties and promote a globally engaged scientific workforce focused on an important agricultural problem. This award would benefit greatly the Ph.D. training of Arianne Cease by allowing her the flexibility to conduct research and make connections with Chinese colleagues. This research will enable a highly interdisciplinary collaboration between a group of NSF-funded ecologists (including one of Ceases coadvisors, Dr. James Elser), a large group of grasshopper biologists and grassland botanists at the Chinese Academy of Sciences (CAS), Institutes of Zoology (IOZ) and Botany (IOB), and insect physiologists (including Ceases other co-advisor, Dr. Jon Harrison). Collaborative activities funded by this award will include research projects at the Beijing Institute of Life Sciences and the State Key Laboratory of Integrated Management of Insect & Rodent Pests at IOZ, CAS and at IMGERS involving a doctoral student and multiple Chinese and US scientists.
|Effective start/end date||5/1/10 → 4/30/12|
- National Science Foundation (NSF): $14,988.00