Neutral Theory and Beyond: A Systematic Review of Molecular Evolution Education

Molecular evolution—including the neutral theory of molecular evolution—is a major sub-discipline of evolution and is widely taught in undergraduate evolution courses. However, despite its ubiquity, there have not been any previous attempts to compile and review the molecular evolution education literature. Here, we draw upon the framework proposed in a past literature review examining the broader evolution education landscape to conduct a literature review of papers related to molecular evolution education, classifying the contributions of such papers to evolution pedagogy as well as evolution education research. We find that there remains very limited coverage of molecular evolution in the education literature, with existing papers focusing primarily on providing new instructional modules and strategies for teaching molecular evolution. Our work suggests several areas of critical need as well as opportunities to advance evolution education and evolution education research, including compiling instructional goals for the sub-discipline, developing validated assessments, and investigating student thinking related to molecular evolution. We conclude by providing general strategies, advice, and a novel curricular activity for teaching molecular evolution and the neutral theory of molecular evolution

Contrasting patterns of evolutionary constraint and novelty revealed by comparative sperm proteomic analysis in Lepidoptera

Background: Rapid evolution is a hallmark of reproductive genetic systems and arises through the combined processes of sequence divergence, gene gain and loss, and changes in gene and protein expression. While studies aiming to disentangle the molecular ramifications of these processes are progressing, we still know little about the genetic basis of evolutionary transitions in reproductive systems. Here we conduct the first comparative analysis of sperm proteomes in Lepidoptera, a group that exhibits dichotomous spermatogenesis, in which males produce a functional fertilization-competent sperm (eupyrene) and an incompetent sperm morph lacking nuclear DNA (apyrene). Through the integrated application of evolutionary proteomics and genomics, we characterize the genomic patterns potentially associated with the origination and evolution of this unique spermatogenic process and assess the importance of genetic novelty in Lepidopteran sperm biology. Results: Comparison of the newly characterized Monarch butterfly (Danaus plexippus) sperm proteome to those of the Carolina sphinx moth (Manduca sexta) and the fruit fly (Drosophila melanogaster) demonstrated conservation at the level of protein abundance and post-translational modification within Lepidoptera. In contrast, comparative genomic analyses across insects reveals significant divergence at two levels that differentiate the genetic architecture of sperm in Lepidoptera from other insects. First, a significant reduction in orthology among Monarch sperm genes relative to the remainder of the genome in non-Lepidopteran insect species was observed. Second, a substantial number of sperm proteins were found to be specific to Lepidoptera, in that they lack detectable homology to the genomes of more distantly related insects. Lastly, the functional importance of Lepidoptera specific sperm proteins is broadly supported by their increased abundance relative to proteins conserved across insects. Conclusions: Our results identify a burst of genetic novelty amongst sperm proteins that may be associated with the origin of heteromorphic spermatogenesis in ancestral Lepidoptera and/or the subsequent evolution of this system. This pattern of genomic diversification is distinct from the remainder of the genome and thus suggests that this transition has had a marked impact on lepidopteran genome evolution. The identification of abundant sperm proteins unique to Lepidoptera, including proteins distinct between specific lineages, will accelerate future functional studies aiming to understand the developmental origin of dichotomous spermatogenesis and the functional diversification of the fertilization incompetent apyrene sperm morph

“There⇔s a human being here”: A doctoral class uses duoethnography to explore invisibility, hypervisibility, and intersectionality

Aim/Purpose This paper contributes to the scholarly literature on intersectionality and social injustice (invisibility, hypervisibility) in higher education and serves as a model for enacting doctoral education where research, theory, and practice converge. Background Invisibility and hypervisibility have long been documented as social injustices, but very little literature has documented how doctoral students (who are also university employees) make meaning of intersecting privileges and oppressions within post-secondary hierarchies. Methodology This study used a 10-week Duoethnography with co-researchers who were simultaneously doctoral students, staff, instructors, and administrators in higher education settings. Contribution This paper offers a unique glimpse into currere—the phenomenon of theory and practice converging—to offer an intensive interrogation of life as curriculum for five doctoral students and a professor. Findings This paper illuminates rich meaning-making narratives of six higher educators as they grappled with invisibility and hypervisibility in the context of their intersecting social identities as well as their varied locations within post-secondary hierarchies/power structures. Recommendations Duoethnography can be an effective strategy for social justice praxis in doctoral for Practitioners programs as well as other higher education departments, divisions, or student organizations. Recommendations Researchers can use Duoethnography to explore a plethora of social justice is-for Researchers sues in doctoral education and across staff, faculty, and Ph.D. student experiences within the power structures of post-secondary education. Future Research Future research can more deeply explore social injustices and the intersections of not only social identities, but also social locations of doctoral students who are simultaneously employees and students in a university hierarchy

Disrupting cisheteronormativity in STEM through humanism

Cisheteronormativity is prevalent throughout college STEM discourses and classrooms. In this paper, we present findings from a U.S. based study focused on the experiences of collegiate STEM students with minoritized identities of sexuality and gender (MIoSG) as the backdrop for discussing how current harmful ideologies in STEM perpetuate cisheteronormativity through discursive practice. We propose that humanistic classrooms and pedagogy can work to dismantle cisheteronormative D/discourses in STEM and create MIoSG inclusive STEM classrooms and programs. Our findings highlight the ways participants experienced cisheteronormative D/discourses in their collegiate STEM contexts. We discuss how these experiences might be mitigated through humanistic educational approaches in college STEM contexts. Our aim is for readers to gain simultaneous theoretical and pragmatic insights on how cisheteronormative D/discourses operate in collegiate STEM classrooms and educational programs