| description |
The microbial communities that inhabit the gut of animals play essential roles in host biology including nutrient provisioning, regulation of tissue development, and immune system development. Both ecological and evolutionary forces are thought to have shaped these communities. However, previous efforts to quantify the extent to which different factors contribute to the structure of gut bacterial communities have targeted either a range of host diversity too narrow to analyze ecological drivers of community structure, or so wide that diet and phylogeny are tightly correlated, and thus difficult to disentangle. In order to assess the relative contribution of host ecology (including dietary specializations) and evolution (phylogenetic relationships) in shaping gut microbiome diversity we have chosen to study the phyllostomid bats (Chiroptera: Phyllostomidae). Phyllostomid bats span almost the entire dietary diversity known for terrestrial mammals, with omnivorous, insectivorous, carnivorous, hematophagous, nectarivorous, and frugivorous species. Crucially, there is a robust phylogenetic framework for this group that indicates dietary specialization has evolved multiple times from insect-feeding ancestors. Nectar feeding and carnivory have each evolved twice, the inclusion of some fruit in the diet has evolved 5 times, and blood-feeding and extreme frugivory have evolved one time each. Repeated instances of the evolution of dietary specializations enable analyses that separate host diet and environment from phylogeny as drivers of bacterial community structure. To date, we have collected 96 fecal samples for 38 species that span the dietary diversity of the clade. All of these samples were collected in the field in Belize and Ecuador, and thus represent the microbiome of these bats in their natural habitat. We would like to generate 16S and shotgun metagenomic sequences for these samples to assess community membership and function. This project represents a significant step forward in the characterization of vertebrate microbiome because it enables hypotheses on the relative importance of different factors in structuring bacterial communities to be explicitly tested. These data will also provide insight into the role the gut microbial community plays in adaptation to novel diets. |