Fellowship for Allyssa Kilanowski: Assessing Density in the Dark: Juvenile Insect Feeding Vibrations as a Cue for Dispersal and Consequences for Landscape Population Dynamics

The individuals that disperse, reach a crop first, and reproduce early in infestations are a small portion of the population, but have a disproportionately large impact on the growth and genetic composition of the population. Therefore, it is crucial to understand what causes a small portion of the population to disperse, and for that small portion, evaluate the traits they possess that facilitate establishment. In this proposal, my objective is to investigate the proximate cues of dispersal and the consequences of among-individual variation in dispersal on recently founded population dynamics. My central hypothesis is that individuals vary in their sensitivity to the cues that trigger dispersal and the individuals that disperse have genetically correlated reproductive traits that facilitate population growth. The rationale for the proposed research is that an understanding of dispersing individuals, rather than the population average, will allow for more targeted treatments of the small subset of a pest population that can cause the most damage via spread of the infestation to other locations. My specific objectives are: 1) Assess the extent to which vibrations function as a cue for dispersal through recordings and playback experiments of larval feeding vibrations; and 2) Determine reproductive traits that are genetically correlated with long distance dispersal by comparing reproductive traits in two populations artificially selected for long- and short-distance dispersal. I will use cowpea bean beetle (Callosobruchus maculatus), a pest that damages stored legume seeds, to experimentally test the cues that trigger dispersal and observe the consequences of dispersal on landscape scale population dynamics. My technique of artificially selecting for dispersal behavior will elucidate the relationship between behavioral evolution and dispersal, thus making my results broadly applicable to multiple systems, and addressing priorities of AFRI Plant Health and Production.