Microbial Succession on Honey Bee Body Surfaces Reflects Behavioral Maturation

Behavioral maturation is essential for the proper functioning of honey bee societies and is regulated by multiple factors such as juvenile hormone (JH) and nutritional deficiency. Although recent studies have shown that surface-associated microbiota in insects can modulate host behavior, the relationship between body surface microbiota and behavioral maturation in honey bees remains largely unexplored. This study aimed to determine whether the surface microbial communities of honey bees shift with behavioral maturation. By using 16S rRNA gene amplicon sequencing, we analyzed the surface microbiota of worker bees at different behavioral stages (newly emerged bees, nurses, and foragers) in both Eastern honey bee Apis cerana and Western honey bee Apis mellifera. The results showed that in both honey bee species, nurse bees exhibited the lowest microbial diversity, while forager bees showed the highest, and newly emerged bees had an intermediate level of microbial diversity. Moreover, beta diversity analyses revealed that the body surface microbiota of worker bees significantly varied across behavioral stages in both bee species and differed between the two bee species at the same behavioral stage. Additionally, in both bee species, at the phylum level, Pseudomonadota, Bacillota, and Actinobacteriota dominated the worker bee body surface microbiota; at the genus level, foragers had more Gilliamella, while nurses harbored more Lactobacillus. Together, our findings reveal the emergence of distinct microbial signatures on honey bee body surfaces during behavioral maturation.