D3140: Phylosymbiosis in fungus-gardening ants

Microbiomes are frequently so integrally connected to their associated host that the pair can be conceptualized as a single unit, or symbiome. In recent years, study of this partner specificity has revealed that many host phylogenies are concordant with the phylogenies of their associated microbial communities, a phenomenon known as phylosymbiosis. The obligate symbiosis of fungus-gardening ants represents a novel subject for phylosymbiosis study, as this symbiome contains multiple hosts and multiple associated microbiomes in a complex interconnected whole. Here we apply 16S rRNA gene analysis in combination with analysis of nuclear genes and SNPs to determine if phylosymbiosis is present between host ants, fungal symbionts, and bacterial microbiomes of five neoattini ant species. Our results demonstrate the presence of phylosymbiosis within the attine symbiome, specifically between the ant hosts and the ant-associated microbiome. Our results also suggest that fungal symbiont identity may play a larger role in attine microbiome structure than previously thought, and that geographic impacts on microbiome structure should be routinely incorporated when evaluating attine microbiomes.