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During the struggle for survival, populations occasionally evolve new functions that give them access to untapped ecological opportunities. Theory suggests that coevolution between species can promote the evolution of such innovations by deforming fitness landscapes in ways that open new adaptive pathways. We directly tested this idea by using high-throughput gene editing-phenotyping technology (MAGE-Seq) to measure the fitness landscape of a virus, bacteriophage λ, as it coevolved with its host, the bacterium Escherichia coli . An analysis of the empirical fitness landscape revealed mutation-by-mutation-by-host-genotype interactions that demonstrate coevolution modified the contours of λ’s landscape. Computer simulations of λ’s evolution on a static versus shifting fitness landscape showed that the changes in contours increased λ’s chances of evolving the ability to use a new host receptor. By coupling sequencing and pairwise competition experiments, we demonstrated that the first mutation λ evolved en route to the innovation would only evolve in the presence of the ancestral host, whereas later steps in λ’s evolution required the shift to a resistant host. When time-shift replays of the coevolution experiment were run where host evolution was artificially accelerated, λ did not innovate to use the new receptor. This study provides direct evidence for the role of coevolution in driving evolutionary novelty and provides a quantitative framework for predicting evolution in coevolving ecological communities. 

ABSTRACT Undergraduate research plays an important role in the development of science students. The two most common forms of undergraduate research are those in traditional settings (such as internships and research-for-credit in academic research labs) and course-based undergraduate research experiences (CUREs). Both of these settings offer many benefits to students, yet they have unique strengths and weaknesses that lead to trade-offs. Traditional undergraduate research experiences (UREs) offer the benefits of personalized mentorship and experience in a professional setting, which help build students’ professional communication skills, interest, and scientific identity. However, UREs can reach only a limited number of students. On the other end of the trade-off, CUREs offer research authenticity in a many-to-one classroom research environment that reaches more students. CUREs provide real research experience in a collaborative context, but CUREs are not yet necessarily equipping students with all of the experiences needed to transition into a research lab environment outside the classroom. We propose that CURE instructors can bridge trade-offs between UREs and CUREs by deliberately including learning goals and activities in CUREs that recreate the benefits of UREs, specifically in the areas of professional communication, scientific identify, and student interest. To help instructors implement this approach, we provide experience- and evidence-based guidance for student-centered, collaborative learning opportunities. 

In response to the outbreak of COVID-19 the national landscape of higher education changed quickly and dramatically to move “online” in the Spring semester of 2020. While distressing to both faculty and students, it presents a unique opportunity to explore how students responded to this unexpected and challenging learning situation. In four undergraduate STEM courses that incorporated course-based undergraduate research experiences (CUREs)—which are often focused on discovery learning and laboratory research—we had an existing study in progress to track students' interest development at five time points over the Spring 2020 semester. Via this ongoing study we were able to investigate how students stay engaged in their college science courses when facing unexpected challenges and obstacles to their learning. Longitudinal survey data from 41 students in these CURE courses demonstrated that students' situational interest dropped significantly when their CURE courses unexpectedly shifted from hands-on, discovery-based, and laboratory-based instruction to online instruction. Although we observed a dramatic decline in student interest in general after the CURE courses moved fully online, the decline rates varied across students. Students who were able to make meaningful connections between the learning activities and their personal or career goals were more likely to maintain a higher level of interest in the course. Implications for practice are discussed. 

Successful therapies to combat microbial diseases and cancers require incorporating ecological and evolutionary principles. Drawing upon the fields of ecology and evolutionary biology, we present a systems‐based approach in which host and disease‐causing factors are considered as part of a complex network of interactions, analogous to studies of “classical” ecosystems. Centering this approach around empirical examples of disease treatment, we present evidence that successful therapies invariably engage multiple interactions with other components of the host ecosystem. Many of these factors interact nonlinearly to yield synergistic benefits and curative outcomes. We argue that these synergies and nonlinear feedbacks must be leveraged to improve the study of pathogenesis in situ and to develop more effective therapies. An eco‐evolutionary systems perspective has surprising and important consequences, and we use it to articulate areas of high research priority for improving treatment strategies.