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Synopsis Advanced biology courses, particularly terminology-heavy organismal biology courses, pose unique challenges, which were further compounded by the Covid-19 pandemic. While attending to instructional strategies is one evident way to address these challenges, grading schemes can also be modified or completely restructured to accomplish this goal. What if the grading expectations could be aligned to how students learn in a way that supports their agency and empowers them? What if our grading schemes facilitate learning in students and provide opportunities for students to further study the material, even after they performed poorly in those areas? This paper unpacks the perspectives, course procedures, and thinking in two advanced biology courses that led the instructor to move away from traditional grading procedures and to adopt a more open grading schematic that facilitated student change and learning. The resulting grading model aligns with applied cognitive theories on knowledge acquisition and would be of interest to instructors interested in focusing on student learning progression and student improvement and retention in biology and other STEM subjects. 

Synopsis Vertebral deformities such as abnormal curvatures and shapes may influence kinematics of fishes during swimming. Our study examines the vertebral deformities of hatchery-reared lumpfish (Cyclopterus lumpus) to better understand the effects of vertebral deformity on swimming kinematics. We recorded and analyzed videos of 50 juvenile lumpfish that were being raised as cleaner fish for salmonid farms. Each lumpfish was observed in 10-s video intervals and then euthanized for X-ray visualization of the skeleton. We used midline tracking to calculate speed, tailbeat amplitude, stride length, tailbeat frequency, and tail curvature during volitional swimming. Body shape analysis using 2D landmarking and principal component analysis showed that there was a significant relationship between the number of deformities and body shape from a dorsal view. We also found that body shape from a lateral view was a significant predictor of speed and stride length. We expected that an increase in deformity would cause a change in tail curvature and a decrease in speed, stride length, tailbeat frequency, and tail amplitude. Instead, we found that the lumpfish swimming was mostly unaffected by the deformity. There was only a significant relationship between tailbeat amplitude and number of early compressed vertebrae. Since vertebral deformities had a significant relationship with body shape, there was also an indirect effect of deformity on swimming speed. 

Abstract Convergent evolution is at the forefront of many form-function studies. There are many examples of multiple independent lineages evolving a similar morphology in response to similar functional demands, providing a framework for testing hypotheses of form-function evolution. However, there are numerous clades with underappreciated convergence, in which there is a perceived homogeneity in morphology. In these groups, it can be difficult to investigate causal relationships of form and function (e.g., diet influencing the evolution of jaw morphology) without the ability to disentangle phylogenetic signal from convergence. Leuciscids (Cypriniformes: Leuciscidae; formerly nested within Cyprinidae) are a species-rich clade of fishes that have diversified to occupy nearly every freshwater trophic niche, yet are considered to have relatively low morphological diversity relative to other large freshwater clades. Within the North American leuciscids, many genera contain at least one herbivore, insectivore, and larvaphage. We created 3D models from micro-computed tomography scans of 165 leuciscid species to measure functionally relevant traits within the pharyngeal jaws of these fishes. Using a published phylogeny, we tested these metrics for evolutionary integration, phylogenetic signal, and correlation with diet. Measurements of the pharyngeal jaws, muscle attachment areas, and teeth showed strong positive evolutionary correlation with each other and negative evolutionary correlation with measurements of the inter-ceratobranchial ligament (ICB ligament). Using diet data from published literature, we found extensive dietary convergence within Leuciscidae. The most common transitions we found were between herbivorous and invertivorous taxa and between insectivore types (aquatic vs. terrestrial). We document a trade-off in which herbivorous leuciscids have large teeth, short ICB ligaments, and large muscle attachment areas, whereas insectivorous leuciscids showed the opposite pattern. Inverse patterns of morphological integration between the ICB ligament the rest of the pharyngeal jaw correspond this dietary trade-off, which indicates that coordinated evolution of morphological traits contributes to functional diversity in this clade. However, these patterns only emerge in the context of phylogeny, meaning that the pharyngeal jaws of North American leuciscids converge by similar means (structural changes in response to dietary demands), but not necessarily to similar ends (absolute phenotype).