U.S. flag

An official website of the United States government, Department of Justice.

Gene Expression Correlates of Facultative Predation in the Blow Fly Chrysomya Rufifacies (Diptera: Calliphoridae)

NCJ Number
Ecology and Evolution Volume: 9 Issue: 15 Dated: 2019 Pages: 8690-8701
Date Published
12 pages

This study integrated behavioral assays and transcriptomic analysis of facultative predation in a blow fly (Diptera: Calliphoridae) to assess the prevalence, effect, and correlated gene expression of facultative predation by the invasive species Chrysomya rufifacies.


The effects of intraguild predation (IGP) on omnivores and detritivores are relatively understudied compared to work on predator guilds. Functional genetic work in IGP is even more limited, but its application can help answer a range of questions related to ultimate and proximate causes of this behavior. In the current study, field work that observed donated human cadavers indicated that facultative predation by C. rufifacies on the native blow fly Cochliomyia macellaria was rare under undisturbed conditions, owing in part to spatial segregation between species. Laboratory assays under conditions of starvation showed predation had a direct fitness benefit (i.e., survival) to the predator. As a genome is not available for C. rufifacies, a de novo transcriptome was developed and annotated using sequence similarity to Drosophila melanogaster. Under a variety of assembly parameters, several genes were identified as being differentially expressed between predators and nonpredators of this species, including genes involved in cell-to-cell signaling, osmotic regulation, starvation responses, and dopamine regulation. Results of this work were integrated to develop a model of the processes and genetic regulation controlling facultative predation. (publisher abstract modified)

Date Published: January 1, 2019