The local environment plays a key role in the health and diversity of the gut of wild bees, which could help detect invisible stressors and early indicators of potential threats.
Three species of carpenter bees are found in North America, Asia and Australia. The analysis allowed them to gain insight into the bee's diet and environment.
The researchers found that solitary bees get their health benefits from their environment, rather than from their nest mates. The bees lay their eggs in the stalks of the plants.
"This may make them better bio-indicators as they are much more sensitive to their environment," says Faculty of Science Associate Professor Rehan.
Machine learning tools were able to predict which population each bee was drawn from the unique metagenomics and microbiomes of the local population.
The research team found crop pathogens in the bee's gut, which were previously only found in honeybees.
Rehan says that the pathogens are not necessarily harmful to bees, but the wild bees could potentially be a problem for agriculture. Bee pollination contributes to ecological and agricultural health worldwide in addition to more than $200 billion in annual agricultural services.
Establishing a baseline of what a healthy microbiome looks like in wild bees allows scientists to compare species across continents and populations.
Rehan says that they can look at bee health in a systematic way. The long-term goal is to be able to use these tools to detect early signs of stress and habitats in need of restoration or preservation. It needs to be developed like a diagnostic tool for bee health.
The researchers think they have captured the core of the bees. The beneficialbacteria they found in the carpenter bee species helped with metabolism and genetics. The species of Lactobacillus that they detected is essential for good gut health and is found in most bee lineages. The immune system may be boosted by the presence of lactobacteria.
A recent paper published in the journal Environmental DNA by Rehan and her graduate student found that the small carpenter bee, Ceratina calcarata, did not have the beneficial bacterium, Lactobacillus, in their colony.
Rehan said this raises red flags. We are looking at more nuanced urban, rural and long-term data to understand the environmental stressors. It can give us an indication of a population or species in threat if we see deviations from what we are used to.
Metagenomic methods could provide important insights into wild bee ecology and health.
We've been experimenting with this approach in a few species, but we want to study dozens of wild bee species and compare them. Two studies are establishing the foundation. The tools for a new era of bee research are being built.More information: Comparative metagenomics reveals expanded insights into intra- and interspecific variation 2 among wild bee microbiomes, Communications Biology (2022). Journal information: Communications Biology