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Editors contains: "Powell, Roger"

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  1. Powell, Roger (Ed.)
    Abstract In the past 30 years, leaders in undergraduate education have called for transformations in science pedagogy to reflect the process of science as well as to develop professional skills, apply new and emerging technologies, and to provide more hands-on experience. These recommendations suggest teaching strategies that incorporate active learning methods that consistently increase learning, conceptual understanding, integration of subject knowledge with skill development, retention of undergraduate students in science, technology, engineering, and mathematics (STEM) majors, and inclusivity. To gain insight into current practices and pedagogy we surveyed members of the American Society of Mammalogists in 2021. The survey consisted of both fixed-response questions (e.g., multiple-choice or Likert-scale) and open-ended questions, each of which asked instructors about the structure and content of a Mammalogy or field Mammalogy course. In these courses, we found that lecturing was still a primary tool for presenting course content or information (x¯= 65% of the time); nonetheless, most instructors reported incorporating other teaching strategies ranging from pausing lectures for students to ask questions to incorporating active learning methods, such as debates or case studies. Most instructors reported incorporating skill development and inclusive teaching practices, and 64% reported that they perceived a need to change or update their Mammalogy courses or their teaching approaches. Overall, our results indicate that Mammalogy instructors have a strong interest in training students to share their appreciation for mammals and are generally engaged in efforts to increase the effectiveness of their teaching through the incorporation of more student-centered approaches to teaching and learning. 
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  2. Powell, Roger (Ed.)
    Abstract The teaching practices used in college science classrooms have a profound influence on which students pass their courses (and continue to major in science) and which are ‘weeded out.’ Students from traditionally marginalized backgrounds have lower grades and learning gains compared to their nonmarginalized peers in courses that rely heavily on lecture and high-stakes exams. This achievement gap narrows or disappears when instructors use student-centered, evidence-based teaching practices. These teaching practices can include actions that shape our classroom environment, communicate course material, and assess student learning. In this paper, we provide a summary of the evidence supporting the use of student-centered teaching practices, followed by examples of several effective evidence-based teaching practices that can be integrated into organismal courses. Examples include faculty mindset for inclusion, teaching practices to increase student confidence and to reduce stereotype threat, increasing course structure by spreading points among several different types of activities, several active learning methods, jigsaws, Scientist Spotlights, course-based undergraduate research experiences, and inquiry-based labs. Each example is linked to supporting resources to help instructors easily implement these practices in their classrooms. The American Society of Mammalogists endeavors to be equitable and inclusive through numerous initiatives, and modifying our teaching practices can increase equity and inclusion of future mammalogists into our own classrooms. 
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  3. Powell, Roger (Ed.)
    Abstract Island biogeography theory (IBT) explains and estimates large-scale ecological patterns among islands and isolated habitat patches. Specifically, IBT predicts that the number of species per habitat patch differs as a function of area and isolation as a result of local colonization and extinction. Accurate estimates of species richness are essential for testing predictions of IBT, but differences in detectability of species can lead to bias in empirical data. Hierarchical community models correct for imperfect detection by leveraging information from across the community to estimate species-specific occupancy and detection probabilities. Using the fragmented Ozark glades as our model system, we constructed a hierarchical community model to 1) estimate site-level and regional species richness of small mammals while correcting for detection error, and 2) determine environmental covariates driving occupancy. We sampled 16 glades in southwestern Missouri in summer 2016–2017 and quantified mammal community structure within the glade network. The detected species pool included eight species, and the model yielded a regional species estimate of 8.6 species, with a mean of 3.47 species per glade. Species richness increased with patch area but not isolation, and effects of patch shape varied between species in the community. 
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  4. Powell, Roger (Ed.)
    Abstract Quaternary climatic oscillations affected species distributions worldwide, creating cycles of connectivity and isolation that impacted population demography and promoted lineage divergence. These effects have been well studied in temperate regions. Taxa inhabiting mesic montane habitats in tropical ecosystems show high levels of endemism and diversification in the distinct mountain ranges they inhabit; such a pattern has commonly been ascribed to past climatic oscillations, but few phylogeographic studies have tested this hypothesis. Here, we combine ecological niche models of species distributions with molecular data to study phylogeographic patterns in two rodents endemic to the highlands of Costa Rica and western Panama (Reithrodontomys creper and Nephelomys devius). In so doing, we apply a novel approach that incorporates a basic ecological principle: the expected positive relationship between environmental suitability and population abundance. Specifically, we use niche models to predict potential patterns of population connectivity and stability of different suitability levels during climatic extremes of the last glacial–interglacial cycle; we then test these predictions with population genetic analyses of a mitochondrial and a nuclear marker. The detailed predictions arising from the different levels of suitability were moderately to highly congruent with the molecular data depending on the species. Overall, results suggest that in these tropical montane ecosystems, cycles of population connectivity and isolation followed a pattern opposite to that typically described for temperate or lowland tropical ecosystems: namely, higher connectivity during the colder glacials, with isolation in montane refugia during the interglacials, including today. Nevertheless, the individualistic patterns for each species indicate a potentially wide gamut of phylogeographic histories reflecting particularities of their niches. Taken together, this study illustrates how phylogeographic inferences may benefit from niche model outputs that provide more detailed predictions of connectivity and finer characterizations of potential refugia through time. 
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