Investigating the role of S. piceifrons piceifrons gut bacteria in behavioral manifestations of locust phase shift

Locusts possess the tendency to exhibit two distinct phenotypes as part of a phenomenon known as locust-phase polyphenism. The two phenotypes are solitarious and gregarious, with the latter being associated with the formation of large swarms and destruction of vegetation and important food crops. The underpinning mechanisms facilitating the transition from a solitary phase to gregarious are not fully elucidated. The gut microbiome of insects has been shown to play invaluable roles in their physiology and survival. In locusts, pheromones released as a consequence of the activity of gut bacteria have been implicated as a driver of gregarization. This coupled with evidence suggesting a role of the gut microbiota in behavioral modulation in other insects, make locusts’ gut microbiome worth exploring as a potential contributor to phase shift. Here, I investigate whether the gut microbiome of Central American locust (S. piceifrons piceifrons) contributes to phase shift. First, field-caught solitary and gregarious locusts were subjected to comparative analysis of gut bacteria using 16S amplicon sequencing. Then, I perturbed the guts of lab reared S. piceifrons piceifrons using either antibiotic (broad sprectrum) or a bacteriophage (species specific) to observe how that impacts the behavior of a gregarious locust using a behavioral arena. I hypothesize that the gut bacteria of gregarious field-caught S. piceifrons piceifrons will be more diverse in relation to their solitary conspecifics. Additionally, I predict that the antibiotic and bacteriophage treatments will alter the behavior of gregarious S. piceifrons piceifrons. This work was supported by NSF # 2021795.