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Supporting changes in undergraduate science, technology, engineering, and mathematics (STEM) instruction requires an understanding of the relationship between STEM instructors' conceptions and practices. In this study, the authors used the Teacher-Centered Systematic Reform (TCSR) model as a framework to understand how instructors' conceptions are related to their instructional practices. This multiple methods study included interviews and classroom observations of 22 STEM instructors. We used qualitative methods to describe instructors' conceptions of how students learn and quantitative methods, including a hierarchical cluster analysis, to analyze the types of relationships that exist between their conceptions and practices. Results indicated instructors had a wide range of conceptions that exist along a continuum from teacher-centered to student-centered. While many faculty members perceived student-centered practices as valuable, they conceptualized these practices in different ways. Instructors implemented a wide range of instructional practices, and these practices varied independently of conceptions. We identified three distinct clusters of participants based on the relationships between instructors' conceptions and practices: congruent lecturers, congruent active learning facilitators, and incongruent lecturers. In the first two clusters, instructors' conceptions were aligned with their instructional practices. However, incongruent lecturers thought that students learn through active learning approaches but primarily lectured in their courses. Instructors in this group described several personal and contextual factors that influenced the relationship between their conceptions and practices. The results include an in-depth portrayal of one participant in each cluster. We found that student-centered conceptions may be necessary but are not sufficient for instructors to implement active learning. Implications focus on instructional and institutional change efforts. To promote instructional change most effectively, it is important to address each component of the TCSR model, including personal and contextual factors. A focus on conceptions and practices alone may not sufficiently support faculty members in overcoming barriers that limit active learning instruction.

Supporting changes in undergraduate science, technology, engineering, and mathematics (STEM) instruction requires an understanding of the relationship between STEM instructors' conceptions and practices. In this study, the authors used the Teacher‐Centered Systematic Reform (TCSR) model as a framework to understand how instructors' conceptions are related to their instructional practices. This multiple methods study included interviews and classroom observations of 22 STEM instructors. We used qualitative methods to describe instructors' conceptions of how students learn and quantitative methods, including a hierarchical cluster analysis, to analyze the types of relationships that exist between their conceptions and practices. Results indicated instructors had a wide range of conceptions that exist along a continuum from teacher‐centered to student‐centered. While many faculty members perceived student‐centered practices as valuable, they conceptualized these practices in different ways. Instructors implemented a wide range of instructional practices, and these practices varied independently of conceptions. We identified three distinct clusters of participants based on the relationships between instructors' conceptions and practices: congruent lecturers, congruent active learning facilitators, and incongruent lecturers. In the first two clusters, instructors' conceptions were aligned with their instructional practices. However, incongruent lecturers thought that students learn through active learning approaches but primarily lectured in their courses. Instructors in this group described several personal and contextual factors that influenced the relationship between their conceptions and practices. The results include an in‐depth portrayal of one participant in each cluster. We found that student‐centered conceptions may be necessary but are not sufficient for instructors to implement active learning. Implications focus on instructional and institutional change efforts. To promote instructional change most effectively, it is important to address each component of the TCSR model, including personal and contextual factors. A focus on conceptions and practices alone may not sufficiently support faculty members in overcoming barriers that limit active learning instruction. [ABSTRACT FROM AUTHOR]

Elucidating the adaptations that promote flight in animals can aid the understanding of evolution and species divergence, and/or provide inspiration for aerospace engineering and the design of better aerial vehicles. The famed long-distance migration of monarch butterflies in North America still holds many questions and opportunities for inspiration. For example, there is little research on whether the monarch's primary wing colors themselves (black, orange, or white) have any aerodynamic or migration function. Dark colors on wings of other animals have recently been shown to aid flight by enhancing solar absorption, which reduces drag forces. However, too much black surface could be problematic for monarchs, which are exposed to increasing amounts of solar energy along their flightpath. This paper describes the results of two related investigations that attempt to elucidate the importance of wing color to the monarch migration. By measuring the color proportions of nearly 400 monarch wings collected at different stages of their journey, we found, surprisingly, that successful migrants tended to have less black on their wings (about 3% less), but also more white pigment (about 3% more); monarchs have a band of light-colored marginal wing spots. Second, image analysis of museum specimens revealed migratory monarchs had significantly larger white spots, proportional to the wing area, than most non-migratory, New World Danaid butterflies, which argues spot size has evolved along with migratory behavior. Combined, these findings strongly suggest that the long-distance migration itself selects for larger white spots every fall, so that only those individuals with large spots will survive to pass on their genes. Further experimental work is needed to elucidate how the spots aid the migration, but it is possible that they enhance aerodynamic efficiency; other work by the authors demonstrates how alternating white and black pigment on wings can reduce drag. These results will serve as a useful starting point for such endeavors, which should improve understanding of one of the world's most fascinating animal migrations, and also provide practical knowledge for the field of aerospace engineering. [ABSTRACT FROM AUTHOR]

We describe a new species of carpenter ants from Ecuador, which apparently has an obligatory relationship with the ant plants Cecropia membranacea Trécul, C. herthae Diels and C. marginalis Cuatrec. The workers are relatively small and hairy, and based on a number of collections, it does not appear to have major workers. We compare the new species to Camponotus balzani, to which it appears to be similar and which has normal major workers, and also lives in Cecropia spp. [ABSTRACT FROM AUTHOR]