Emerging studies have supported the association between gut microbiome and host behaviors. However, it is unclear whether changes in the gut microbiome cause changes in host behaviors or vice versa. The European honey bee, Apis mellifera, is an excellent animal model for identifying the causal link between microbiome and behavioral changes over the lifetime of the host as the honey bee gut contains a simple microbiome composed of only nine bacterial taxa clusters. In honey bees, division of labor occurs through behavioral maturation where age determines what task a bee does. For example, older bees forage while younger bees perform brood care (nursing) and other in-hive tasks. Single cohort colonies (SCCs), or colonies composed of individuals of the same age, uncouple chronological age effects on honey bee behavioral maturation (nursing → foraging). SCCs results from our previous experiment reveal a highly significant difference in the gut microbiota between nurses and foragers, independent of age, specifically in the abundance of Lactobacillus mellis and Bifidobacterium asteroides
