The gut microbiota affects the social network of honeybees

The gut microbiota influences animal neurodevelopment and behaviour but has not previously been documented to affect group-level properties of social organisms. Here, we use honeybees to probe the effect of the gut microbiota on host social behaviour. We found that the microbiota increased the rate and specialization of head-to-head interactions between bees. Microbiota colonization was associated with higher abundances of one-third of the metabolites detected in the brain, including amino acids with roles in synaptic transmission and brain energetic function. Some of these metabolites were significant predictors of the number of social interactions. Microbiota colonization also affected brain transcriptional processes related to amino acid metabolism and epigenetic modifications in a brain region involved in sensory perception. These results demonstrate that the gut microbiota modulates the emergent colony social network of honeybees and suggest changes in chromatin accessibility and amino acid biosynthesis as underlying processes. Tracking the behaviour of normal versus microbiome-free honeybees in experimental colonies, the authors show that gut microbiota colonization was associated with an increase in the rate and specificity of social interactions among bees and higher abundances of brain metabolites linked to these interactions.

Automated summary

This study reveals that the gut microbiota affects the social behavior of honeybees. Microbiota colonization increases the rate and specialization of head-to-head interactions between bees, and is associated with higher abundances of metabolites in the brain that play roles in social interactions. Microbiota colonization also affects brain transcriptional processes and epigenetic modifications related to amino acid metabolism and sensory perception in honeybees.