Host phylogeny and diet structure its bacterial community: a case study of various fig wasps coexisting in Ficus hispida
The composition of a microbial community may be driven by geographic isolation, diet, and the phylogenies of host organisms. A null hypothesis was that the evolutionary history of microbial communities reflects the phylogenies of their respective hymenopteran hosts. The objective of this study was to test this hypothesis using four fig wasp species (Ceratosolen solmsi Mayr, Apocrypta bakeri Joseph, Philotrypesis pilosa Mayr, and Philotrypesis sp. Forster), which coexist in the spatially isolated fig cavities of Ficus hispida Linnaeus. The bacterial communities of the four fig wasps were investigated using culture-independent methods. The results show that these wasps harbored a total of 53 operational taxonomic units (3% distance cutoff for 16S rDNA sequences), and were dominated by Proteobacteria. Herbivore C. solmsi mainly harbored γ-proteobacteria (65.3%) and Actinobacteridae (23.9%). Potential omnivore P. pilosa was dominated by α- and γ-proteobacteria (80.5% and 4.9%). β-proteobacteria and Acidobacteria represented the majority of the bacterial communities of carnivores Philotrypesis sp. (51.2% and 16.8%) and A. bakeri (52.7% and 12.5%). Contrary to our hypothesis, the bacterial communities of the four fig wasps were clustered into three groups, which might be structured by both the diet and phylogenies of the host species. The fig-fig wasp system provides an isolated model for the extensive exploration of the ecological associations between insects and their microbes.
Lihua Niu, Jinhua Xiao, Liming Niu, Shengnan Bian, Xiufeng Song, Robert W Murphy, Yi Li, Ningxin Wang and Dawei Huang