Ecological dominance is a central concept in the study of interspecies and species-environment relations. Yet, although theoretical and empirical work on ecological dominance has progressed in many scientific disciplines, the psychology of ecological dominance remains understudied. The present research advances theoretical and empirical inquiry on ecological dominance as a psychological construct, examining how it relates to humans’ attitudes, beliefs, and behavior across different relational domains (i.e., intraspecies, interspecies, human-environment). To this end, we validate a novel measure, the Ecological Dominance Orientation (EDO) scale, based on the popular iconic depiction of ecocentric versus anthropocentric arrangements of the relationship between humans, nonhuman animals, and the natural environment. In five pre-registered studies across two countries (N = 2407), we demonstrate that EDO a) relates to various attitudes in a similar fashion both within and between different relational domains, b) is uniquely associated with socially consequential attitudes (i.e., modern sexism, speciesism, dehumanization) above established measures of personal ideology, c) is reliable over time, d) relates to a distinct set of personality correlates, and e) uniquely predicts pro-environmental behavior. This research extends classical Social Dominance Theory (Sidanius & Pratto, 1999) by theorizing about the socio-ecological roots of intergroup, interspecies, and human-environment relations as hierarchically structured power relations. Theoretical implications of social and ecological dominance orientations are discussed.

Clathrin-mediated endocytosis (CME) involves the recruitment of numerous proteins to sites on the plasma membrane with prescribed timing to mediate specific stages of the process. However, how choreographed recruitment and function of specific proteins during CME is achieved remains unclear. Using genome editing to express fluorescent fusion proteins at native levels and live-cell imaging with single-molecule sensitivity, we explored dynamin2 stoichiometry, dynamics, and functional interdependency with actin. Our quantitative analyses revealed heterogeneity in the timing of the early phase of CME, with transient recruitment of 2-4 molecules of dynamin2. In contrast, considerable regularity characterized the final 20 s of CME, during which ∼26 molecules of dynamin2, sufficient to make one ring around the vesicle neck, were typically recruited. Actin assembly generally preceded dynamin2 recruitment during the late phases of CME, and promoted dynamin recruitment. Collectively, our results demonstrate precise temporal and quantitative regulation of the dynamin2 recruitment influenced by actin polymerization.

Understanding how members of the human gut microbiota prioritize nutrient resources is one component of a larger effort to decipher the mechanisms defining microbial community robustness and resiliency in health and disease. This knowledge is foundational for development of microbiota-directed therapeutics. To model how bacteria prioritize glycans in the gut, germfree mice were colonized with 13 human gut bacterial strains, including seven saccharolytic Bacteroidaceae species. Animals were fed a Western diet supplemented with pea fiber. After community assembly, an inducible CRISPR-based system was used to selectively and temporarily reduce the absolute abundance of Bacteroides thetaiotaomicron or B. cellulosilyticus by 10- to 60-fold. Each knockdown resulted in specific, reproducible increases in the abundances of other Bacteroidaceae and dynamic alterations in their expression of genes involved in glycan utilization. Emergence of these alternate consumers was associated with preservation of community saccharolytic activity. Using an inducible system for CRISPR base editing in vitro, we disrupted translation of transporters critical for utilizing dietary polysaccharides in Phocaeicola vulgatus, a B. cellulosilyticus knockdown-responsive taxon. In vitro and in vivo tests of the resulting P. vulgatus mutants allowed us to further characterize mechanisms associated with its increased fitness after knockdown. In principle, the approach described can be applied to study utilization of a range of nutrients and to preclinical efforts designed to develop therapeutic strategies for precision manipulation of microbial communities.