Experimental Evolution on a Wild Mammal Species Results in Modifications of Gut Microbial Communities

Abstract

Comparative studies have shown that diet, life history, and phylogeny interact to determine microbial community structure across mammalian hosts. However, these studies are often confounded by numerous factors. Selection experiments offer unique opportunities to validate conclusions and test hypotheses generated by comparative studies. We used a replicated, 15-generation selection experiment on bank voles (Myodes glareolus) that have been selected for high swim-induced aerobic metabolism, predatory behavior toward crickets, and the ability to maintain body mass on a high-fiber, herbivorous diet. We predicted that selection on host performance, mimicking adaptive radiation, would result in distinct microbial signatures. We collected foregut and cecum samples from animals that were all fed the same nutrient-rich diet and had not been subjected to any performance tests. We conducted microbial inventories of gut contents by sequencing the V4 region of the 16S rRNA gene. We found no differences in cecal microbial community structure or diversity between control lines and the aerobic or predatory lines. However, the cecal chambers of voles selected for herbivorous capability harbored distinct microbial communities that exhibited higher diversity than control lines. The foregut communities of herbivorous-selected voles were also distinct from control lines. Overall, this experiment suggests that differences in microbial communities across herbivorous mammals may be evolved, and not solely driven by current diet or other transient factors.

Captivity affects diversity, abundance, and functional pathways of gut microbiota in the northern grass lizard Takydromus septentrionalis

“…The structure and abundance of gut microbiota vary distinctly among different hosts, yet, the dominant gut microorganisms at the phylum level remain Firmicutes and Bacteroidetes in mammals, reptiles, and amphibians (Duncan et al, 2008;Kohl, Sadowska, Rudolf, Dearing, & Koteja, 2016;Vences et al, 2016;Zhang et al, 2018;Zhao et al, 2018), and Firmicutes and Proteobacteria in birds, fishes, and insects (Dewar, Arnould, Krause, Dann, & Smith, 2014;Li, Zhu, Yan, Ringø, & Yang, 2014;Ye, Amberg, Chapman, Gaikowski, & Liu, 2014;Yun et al, 2014). Notably, Firmicutes can encode the energy metabolism-related enzymes, have the potential to biosynthesize vitamin B, produce diverse kinds of digestive enzymes to break down various substances, and thus help their hosts digest and absorb nutrients (Flint, Scott, Duncan, Louis, & Forano, 2012;Rowland et al, 2018).…”

Population genomics of bank vole populations reveals associations between immune related genes and the epidemiology of Puumala hantavirus in Sweden

“…It also provides genomic resources of tens of thousands RAD-seq markers that will further be available to study genetic diversity, population structure and adaptation in bank voles. They may be very useful to address different issues related to this rodent in a wide array of disciplines such as medical science (Hampton, 2014; Razzauti-Feliu et al, 2015), microbiology (Kohl, Sadowska, Rudolf, Dearing, & Koteja, 2016), or ecology (Mokkonen et al, 2011).…”

Shifting Climates, Foods, and Diseases: The Human Microbiome through Evolution

“…[73] In humans, differences in amylase copy number are associated with variation in the gut microbiome. For example, if dietary practices that emerged at local scales were associated with host genetic changes to improve utilization of those diets (i.e., starch, high protein, dairy), they could then feed back to affect the microbiome.…”