Meta-barcoding of pollen and bacteria in brood provisions of the wild bee Ceratina calcarata

Wild bees are important pollinators but we know very little about their diets and foraging patterns. The bees themselves, and the pollen they collect, are also associated with microbial symbionts but we similarly do not know how these differ with geography and changes in bee diet. To address this, we collected brood provisions from nests of the wild bee Ceratina calcarata from three states, Georgia, Missouri and New Hampshire,broadly encompassing the range of this bee in the United States. A meta-barcoding approach was used to sequence all of the pollen (rbcl) and bacterial (16S) components of the brood provisions. We aimed to determine if the bee's diet varied across it's range and secondly to determine if the bacterial symbionts present within the brood provisions differed with site or the pollen composition.