Diet affects the composition and diversity of the Mammalian gut microbiota
The mammalian gut microbiota is colonized by a complex and dynamic population of microbes, and has been shown to play a substantial role in mediating health and disease in individuals. Although the gut microbiome is subjected to a wide variety of host and environmental factors that influence microbial composition, diet is considered as one of the main drivers involved in shaping the gut microbiome structure. The composition of the mammalian gut microbiota has been shown to correlate with the secretion of specialized enzymes used to metabolize distinct substrates across the three main diet categories: carnivory, omnivory, and herbivory. Herbivores have been shown to have the greatest microbial diversity, driven by the need for microbial assemblages to break down recalcitrant plant fibres into usable energy. In this study, we analyzed alpha and beta diversity from a data set composed of 41 mammalian species spanning across 6 orders. We confirm previous results that mammals belonging to different diet types harbour distinctly different gut microbial communities. We also show that certain microbial families are associated with each of the three diet categories through indicator taxonomy analysis. Furthermore, the relationship between the proportion of plants in the diet and the gut microbial composition in omnivores is inconclusive. Collectively, these results allowed us to further our understanding into the effects of diet on the mammalian gut microbiota.