COS 293-2 - Sympatric North American acorn-nesting ant species possess distinct gut microbiomes

Abstract: Metazoans form important associations with microbes that are influenced by factors like host diet and behavior, and ants have provided a useful system to understand the co-evolution of these host-microbiome interactions. Most prior ant microbiome studies have focused on South American ant species that have close associations with plants (e.g., fungus-farming or nectar-feeding ants), and there is less information about the microbiomes of foraging North American ants. In this study 16S rRNA amplicon sequencing was used to analyze the microbiomes of four sympatric North American acorn-nesting ants species. Results show that these ant species exhibit significantly different prokaryotic gut communities at multiple taxonomic levels. Myrmica rubra, an invasive species, had higher abundances of Spiroplasma than other ant species, and Temnothorax longispinosus had higher levels of Proteobacteria and, in particular, members of the genus Wolbachia. This initial study of North American foraging ants provides an important foundation for further study of ants which have distinct diets from previously studied tropical, plant-associated ants. This study suggests that different species of ants may host unique interactions with microbes that depend on more than just that which they come in contact with in their environment, and that behavioral and dietary mechanisms could be more at play.