Spelman College

ABSTRACT Mayorella species are globally distributed amoeboid protists, yet their diversity remains poorly resolved due to pronounced morphological plasticity and limited molecular data. Freshwater ecosystems of West Africa are particularly underexplored, with virtually no taxonomic or molecular studies addressing Mayorella and most microbial eukaryotes diversity in the region. Here, we describe a new species of Mayorella isolated from Budamu Stream, Ghana, using an integrative morphological and molecular approach. Mayorella budamensis sp. nov. exhibits marked morphological plasticity in size, shape, locomotion, and floating forms. Phylogenetic analyses based on SSU rDNA place the new species within a well-supported Mayorella clade, clustering with geographically diverse but largely unnamed and uncultured lineages. Comparative sequence analyses confirm that M. budamensis sp. nov. is genetically distinct from all sequenced congeners recognized to date. In addition, a second Mayorella isolate recovered from the same locality forms a genetically distinct lineage associated primarily with environmental sequences, indicating a novel evolutionary group. Based on available SSU rDNA data, we recognize up to seven major clades within Mayorella , representing distinct evolutionary lineages with the potential to include additional undescribed species. Together, these findings reveal substantial cryptic diversity and expand the known distribution of Mayorella in understudied African freshwater ecosystems.

This article provides a methodological overview of research using the Carnegie Elective Classification for Community Engagement dataset. Established in 2006 to recognize institutionalized campus-community partnerships, 368 institutions currently hold the classification. In 2023, the Carnegie Elective Classifications Research Lab (CECRL) was formed as an international collaboration with eight co‑labs, structuring data use, expanding access, and fostering a networked community of research practice. In this article, we describe the dataset, showcase current CECRL research trajectories, and discuss emerging and future research possibilities. This article offers scholars a roadmap for leveraging the Carnegie Electives data to advance understanding and evidence‑based strategies for community engagement in higher education.

Objective This study examined the psychometric properties of the Perceived Stress Scale (PSS-10) using Explanatory Item Response Models (EIRMs) to better understand the factors influencing self-reported stress in an understudied population: Black pregnant and postpartum women in the U.S. Method Rasch models for polytomous data were used to evaluate the psychometric properties of the PSS-10. The Linear Logistic Rasch Model (LLRM) and Latent Regression Rasch Model (LRRM) were fit to investigate the influence of item covariates (item content) and person covariates (levels of education and relationship status) on reporting stress. Results The PSS-10 demonstrated acceptable psychometric properties for this population. We found that education level, marital status, and item content significantly affected the level of perceived stress among this target population. Conclusion The EIRM framework is a promising approach for evaluating the PSS-10, emphasizing the need to refine stress assessments and tailor interventions to accurately measure stress in this population.

Intermediate microeconomics is often considered a “weed-out” class that winnows economics majors down to those who can cut it in the tough field of economics. We argue that this mindset unnecessarily gatekeeps economics and that all students should be seen as flowers to be cultivated. We suggest strategies for teaching this course in an inclusive yet rigorous way. First, we discuss sense of belonging, economics identity, active support of students, and student growth mindset. Next, we discuss assessment of students’ quantitative preparation and support of students with weaker math backgrounds. We then encourage active learning, providing specific example activities. We discuss how the material, which can seem abstract, can be made relevant and compelling to undergraduates, including those from underrepresented backgrounds. Finally, we discuss the importance of instructors’ growth mindset with regard to students and the value of communicating the belief that all students can succeed in the course.

ABSTRACTThis article outlines the process of developing a collaborative multi‐sited oral history project on the history, traditions, and ongoing resilience of Black and Indigenous farm and garden practices in the Southeastern United States and Appalachia. The Heirloom Gardens Oral History Project is a collaboration between the Ujamaa Cooperative Farming Alliance, the Spelman College Food Studies Program, and the Princeton Food Project. Our model used student oral historians that we trained in oral history methods and ethics. Our initial goal was to collect oral history interviews and develop an engaging open access multi‐media archive. The project documents seed saving and gardening stories from people who have helped preserve Black and Indigenous foodways, including elders and newer generations of gardeners and small‐scale farmers. The stories serve as an important record of heirloom practices with rich cultural traditions and knowledge. Collectively, the archive documents the movement of seeds, practices, and ideas across people and space. This article details our process of conceiving the project, building collaborations, and the results of 2 years of oral history collections in six different field sites. We believe this project can serve as a model for developing similar oral history projects.

The genera Paramoeba and Neoparamoeba, within the family Paramoebidae (order Dactylopodida), are distinguished by their dactylopodial pseudopodia and the presence of an intracellular eukaryotic symbiont, the Perkinsela-like organism (PLO). Taxonomic classification within these genera has been challenging due to overlapping morphological traits and close phylogenetic relationships. They are marine, with some playing significant roles as parasites. Notably, they have been implicated in sea urchin mass mortality events and are known causative agents of Amoebic Gill Disease (AGD) in fish. Despite their ecological and economic importance, many aspects of their diversity, biology, evolution, and host interactions remain poorly understood. In this study, we describe a novel amoeba species, Paramoeba daytoni n. sp., isolated from Daytona Beach, Florida. Morphological and molecular analyses confirm its placement within the Paramoeba clade, closely related to P. eilhardi, P. karteshi, and P. aparasomata. Phylogenetic assessments using 18S rDNA (18S) and Cytochrome c Oxidase I (COI) markers demonstrate the limitations of the 18S gene for species delineation, highlighting COI as a more reliable genetic marker for this group. Additionally, observations on PLO morphology, movement, and microtubule association provide insights into the endosymbiotic relationship, reinforcing the need for further research into this unique eukaryote-eukaryote symbiosis.

Planktonic diatoms of the genus Planktoniella are characterized by organic extensions from the girdle. Planktoniella species are solitary, except for a colonial form that was first described as Coenobiodiscus muriformis from San Diego Bay, California. We established a culture of Planktoniella muriformis from Mazatlán, Gulf of California, in order to solve its phylogenetic affinities using molecular markers. Beyond the distinct colony morphology, P. muriformis has one marginal rimoportula and absence of mantle ribs, while two rimoportulae and numerous mantle ribs are the signature characteristics in the solitary species of the genus Planktoniella. In the SSU-, LSU rRNA and RuBisCO large subunit (rbcL) gene phylogenies, P. muriformis is nested within sequences from the paraphyletic genus Thalassiosira. The sequences are distantly related to the clade of the type species of Planktoniella, P. sol, and four other congeneric species, and the type species of Thalassiosira or any other thalassiosiroid genera, supporting consideration as an independent genus. In the rbcL gene phylogeny, the sequence of P. muriformis allies with distinct thalassiosiroid genera without bootstrap support, while in the SSU and LSU rRNA gene phylogenies it is nested with support as a sister group of two strains of T. hispida or the strain BEN02-35 identified as Thalassiosira angulata, respectively. The considerable genetic distance between these taxa and P. muriformis, and the lack of distinctive common morphological features do not support their placement in the same genus. Based on analyses of nuclear and chloroplast molecular markers, and the distinctive morphology of P. muriformis, with a unique type of colony formation unknown in any other diatom, we reinstate the genus Coenobiodiscus for P. muriformis.