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The gut microbial communities of mammals provide numerous benefits to their hosts. However, given the recent development of the microbiome field, we still lack a thorough understanding of the variety of ecological and evolutionary factors that structure these communities across species. Metabarcoding is a powerful technique that allows for multiple microbial ecology questions to be investigated simultaneously. Here, we employed DNA metabarcoding techniques, predictive metagenomics, and culture-dependent techniques to inventory the gut microbial communities of several species of rodent collected from the same environment that employ different natural feeding strategies [granivorous pocket mice (Chaetodipus penicillatus); granivorous kangaroo rats (Dipodomys merriami); herbivorous woodrats (Neotoma albigula); omnivorous cactus mice (Peromyscus eremicus); and insectivorous grasshopper mice (Onychomys torridus)]. Of particular interest were shifts in gut microbial communities in rodent species with herbivorous and insectivorous diets, given the high amounts of indigestible fibers and chitinous exoskeleton in these diets, respectively. We found that herbivorous woodrats harbored the greatest microbial diversity. Granivorous pocket mice and kangaroo rats had the highest abundances of the genus Ruminococcus and highest predicted abundances of genes related to the digestion of fiber, representing potential adaptations in these species to the fiber content of seeds and the limitations to digestion given their small body size. Insectivorous grasshopper mice exhibited the greatest inter-individual variation in the membership of their microbiomes, and also exhibited the highest predicted abundances of chitin-degrading genes. Culture-based approaches identified 178 microbial isolates (primarily Bacillus and Enterococcus), with some capable of degrading cellulose and chitin. We observed several instances of strain-level diversity in these metabolic capabilities across isolates, somewhat highlighting the limitations and hidden diversity underlying DNA metabarcoding techniques. However, these methods offer power in allowing the investigation of several questions concurrently, thus enhancing our understanding of gut microbial ecology.

 

The goal of this paper is to share a sociological framework for understanding social justice activism with the intention of improving efficacy of architects’ efforts in addressing contentious social issues. The paper draws on recent sociological scholarship on professions and social movements, which give us new ways of thinking about our agency in affecting social change within and beyond the profession. The paper presents emerging themes based on participant observation and unstructured interviews conducted over the past two years, focused on contemporary activism in architecture. We highlight how professionals use their material resources (design expertise and practice) and their symbolic resources (status in socio-economic, political, and cultural systems) in different forms of contentious political engagement. We offer a sociological framework for distinguishing between ways architects use their work and status in their efforts to achieve social and professional change. The analysis offered in this paper is intended to offer politically-engaged architects (professionals, educators, and students) a framework to assist in their efforts toward shaping equity and justice outcomes for the field and for society.