Microbial communities of wild bees and comparative phylogenetics of key bacterial taxa across the bee tree of life

Recent years have seen a rapidly growing interest in the study of
microbiomes across many animals to understand their health and well-being.
Within bees, much of this work has focused on managed species of
agricultural importance, such as honey bees and bumble bees. However,
unmanaged wild bees are also vital to both agricultural and natural
systems, and studying their microbial associates is essential to better
understand the impacts of microbiomes on bee health. We used metabarcoding
based on 16S and ITS1 loci to identify the bacterial and fungal associates
of adult bees from 16 species representing a diverse sampling of wild bees
common to eastern North America. We measured alpha and beta diversity
across these species which span 10 genera and five families. Additionally,
we conducted a broad phylogenetic comparison of bacterial communities
across bees using previously published 16S datasets, and contrasted these
findings with functional and life history traits across the bee tree of
life. This study provides expanded insights into the adult microbial
associates of wild bees, as well as the broadest investigation to date
into patterns of phylogenetic conservation in bacterial communities across
a total of 42 species representing the five most diverse bee families.