Ecology and Evolution

In this article, we discuss the use of bipartite network analysis to understand and improve interdisciplinary teaching practice. We theorize mathematics and biology as part of a coevolving mutualistic ecosystem. As part of an interdisciplinary teaching initiative, we inventoried mathematics topics appearing in the marine biology classroom and their associated marine context. We then apply techniques of mutualistic bipartite networks analysis to this system to understand the use of mathematical concepts in a marine biology classroom. By analyzing the frequency and distribution of mathematics topics, we see that a variety of mathematical concepts are used across the course with most appearing only a few times. While this is an inherent trait of mutualistic coevolutionary networks, it can create a logistical challenge to supporting mathematics in the marine biology classroom. We find that marine biology topics containing the most mathematics are either close to the instructors research area or were introduced through externally developed educational resources. Finally, we analyze groups of topics that appear connected to each other more frequently to inform both interdisciplinary education development as well as disciplinary support. We also suggest ways to use network metrics to track interdisciplinary connections over time, helping us understand the impact of interventions on interdisciplinary teaching practice.

Evolution by natural selection is recognized as both the most important concept in undergraduate biology and the most difficult to teach. Unfortunately, teaching and assessment of evolution have been impaired by legacy approaches that focus on Darwins original insights and the Modern Synthesis integration of Mendelian genetics, but ignore or downplay advances from what we term the Molecular Synthesis. To create better alignment between instructional approaches and contemporary research in the biosciences, we propose that the primary learning goal in teaching evolution should be for students to connect genotypes, phenotypes, and fitness. To support this approach, we developed and tested assessment questions and scoring rubrics called the Extended Assessing Conceptual Reasoning of Natural Selection (E-ACORNS) instrument. Initial E-ACORNS data suggest that after traditional instruction, few students recognize the molecular synthesis--prompting us to propose that introductory course sequences be re-organized with the molecular synthesis as their central theme.

1.Plastic traits, capable of taking multiple forms, often correlate with one another or with features of the environment when measured over time. These patterns of correlated change are sometimes assumed to reflect adaptive plasticity, such as coevolved "integrated phenotypes" within individuals, synchronisation between social or mating partners, or responses to environmental gradients. 2. Such plasticity is ecologically and evolutionarily important, so there is considerable interest in understanding how it varies between individuals and groups. However, "regression to the mean", the statistical tendency for traits to revert to the average value, may create the illusion of strong bivariate correlations in timeseries data, including substantial but meaningless variation between individuals. 3. We demonstrate this using simulated and real data, revealing how regression to the mean can create bias both within and between samples. We then show, however, that its effects can often be eliminated using autoregressive models. 4. We also offer a detailed discussion of how and why regression to the mean arises, introducing the idea that it is both a statistical and ecological phenomenon.

We investigated if an immunological response (i.e. fibrosis) in threespine stickleback fish can cause divergent selection in its tapeworm Schistocephalus solidus. We pooled tapeworms from six populations in Vancouver Island (BC, Canada) and sequenced the whole genome of these pools. Then we used a modified Population Branch Statistics (PBS) technique based on FST comparisons to find loci under divergent selection due to fibrosis. We found at least eight loci under divergent selection in tapeworm populations caused by this strong immunological respond to infection from the fish.

Ecological research for environmental management occupies a unique and demanding space at the interface of societal needs and academic research. Projects in this space must reconcile stakeholder involvement and real-world applicability with academic requirements such as disciplinary excellence and career advancement. Here, we present a post-hoc account of a 12-year inter- and transdisciplinary research initiative on the management of invasive gobies in central Europe. Based on a synthesis of inputs, outputs, and outcomes, we distill facilitating conditions that increased the likelihood of the project reaching its goals across political, administrative, societal, institutional, team, and individual levels. Rather than "success factors" in a deterministic sense, these are conditions and practices that created a favorable environment for both academic and applied outcomes. The interaction of these domains created windows of opportunity that could be seized for both scientific progress and societal impact. By reflecting from the perspective of natural scientists directly engaged in such a project, we aim to complement existing social science frameworks with an insider view of the lived realities of inter- and transdisciplinary collaboration. Our retrospective can inform policy makers, funders, and institutions seeking to create enabling environments for interface research, and may support fellow natural scientists in proactively preparing the ground for their own initiatives.

To efficiently mitigate biodiversity loss both robust ecological data and broader societal engagement are needed. Citizen science offers a pathway to address these dual challenges by combining data collection with public involvement. Here, we introduce the citizen science project Vienna City Fly, conducted at the Natural History Museum Vienna (NHMW), which used fruit flies (Drosophila) as a model organism group for urban biodiversity research and public engagement. Participants deployed standardized traps across Vienna, enabling systematic sampling and active participation in research, which resulted in hundreds of fly collections, thousands of sampled fly specimens and new insights into the biodiversity and ecology of the collected fly species, demonstrating the feasibility of large-scale ecological research through public collaboration. To assess motivational drivers and perceived impacts of participation, we conducted an online survey (N=59) using the validated psychometric MORFEN-CS scale. Survey results revealed that nature conservation values and the intention to contribute to biodiversity conservation emerged as the strongest drivers of engagement, complemented by sociopolitical responsibility and citizen science-based motivations. Reported outcomes include knowledge gain (61%), more positive attitude toward study organisms (50%), and increased awareness of biodiversity (30%). Satisfaction was very high, with 85% rating their experience at the top of the scale and all participants expressing willingness to join future citizen science projects. Recruitment occurred mainly via social networks, and the sample of participants was highly educated, indicating limits to inclusivity and reach. Our findings demonstrate that citizen science can contribute to robust ecological data collection while gaining knowledge and awareness. Natural history museums, as trusted institutions, play a key role in facilitating such initiatives. Overall, Drosophila research proves to be a suitable field for citizen science, combining accessibility with strong potential for advancing ecological and biodiversity research as well as public engagement in urban biodiversity research.

The COVID-19 pandemic is a national tragedy, one that has focused our attention on both the need to improve science education and the need to confront systemic racism in our country. We know that active learning strategies, in particular research experiences, can engage and empower STEM undergraduates, effectively closing the achievement gap for historically excluded persons. The apprenticeship model for STEM training - supervised research under a dedicated mentor - is highly effective, but out of reach for most students. Recent efforts have demonstrated that Course-based Undergraduate Research Experiences (CUREs) can be an effective approach for making STEM research accessible for all. Our meta-analysis of CUREs finds that published examples now cover the breadth of the typical undergraduate biology curriculum. A thoughtfully designed CURE can go beyond foundational knowledge and analytical thinking to include career-related skills, e.g., teamwork and communication. Similarly, it can be designed with equity as a foundational principle, taking into account the unique contributions of all students and their varying needs. We provide here an example framework (The "Do Science Framework") for making STEM training more effective and inclusive using CUREs. While CUREs do not inherently address equity, there can be no equity in STEM education without equal access to research participation, and progress toward this goal can be achieved using CUREs. However, implementing new CUREs is not a trivial undertaking, particularly at schools with high teaching loads and little or no research infrastructure, including many community colleges. We therefore propose a National Center for Science Engagement to support this transition, building on experiences of current nationally established CUREs as well as the work of many individual faculty. In the aftermath of the COVID-19 pandemic, academia has a renewed responsibility to dismantle structural inequities in education; engaging all STEM students in research can be a key step.

Determining the factors that shape parasite gene flow across complex landscapes is central to understanding the coevolutionary process. In rivers, unidirectional currents, stream drift, may facilitate downstream parasite dispersal, while bifurcating branches may cause population subdivision among branches. The generative habitat processes in rivers can potentially interact with host dispersal to determine gene flow within the aquatic ecosystem. We examined the population genetic structure and gene flow of a trematode infecting semi-aquatic snakes to determine the relative contributions of stream drift, river bifurcations and host dispersal in shaping parasite gene flow in three connected riverine ecosystems. We found the strongest population structure immediately below a recently constructed reservoir at the confluence of the two rivers, with mild structure between one out the the three reaches of the river. Patterns of isolation by distance along linear pathways were not uniform, despite similar path network path lengths. We found the strongest evidence for isolation by distance associated with the river bifurcation. The comparison of terrestrial versus within river network dispersal indicates that parasite transmission between branches occurs along river networks. Short-distance terrestrial dispersal however may be important along some linear networks. Our results highlight the complexity of host-habitat interactions shaping parasite gene flow and the need for empirical data from natural systems to develop accurate models of parasite transmission in rivers.

When a strong selection pressure, such as predation risk, varies widely in space and time, how should prey respond? When risk varies predictably, prey are hypothesized to respond in a risk-sensitive manner. It is less clear how prey should respond when risk varies unpredictably.\n\nAdditionally, prey response may also depend on how predation risk interacts with other selection pressures. Our understanding of the complex action of multiple and variable selection pressures on prey traits is still comparatively poor. Here, we examine how predictable and unpredictable aspects of predation risk act together with another important selection pressure to influence prey behaviour in the rock pool breeding mosquito, Aedes vexans. Through the selection of sites for oviposition, female mosquitoes can influence the predation risk faced by their offspring. We tested how females select oviposition sites, when encountering pools that vary in larval predation risk and desiccation risk. We comprehensively quantified spatial and temporal variation in predation risk by measuring densities of predatory dragonfly nymphs in rock pools of different sizes, along the mosquito breeding season. We also measured hydroperiod length. We next conducted manipulative experiments in rock pools and measured female oviposition responses to variation in predation and desiccation risks. Predation risk varied widely in space and time. Desiccation risk only appeared important for the small pools. Ovipositing females appeared to respond to these multiple aspects of variation in selection pressures. Females seemed to respond to predictable variation by avoiding large pools that permanently harboured predators in natural settings. Female responses were more variable to medium-sized pools with naturally stochastic predator densities, highlighting the role of unpredictability in predation risk in shaping behaviour. Females did not clearly prefer small pools that were naturally devoid of predators but carried high desiccation risk, suggesting that they balance multiple risks - predation versus desiccation - when choosing oviposition sites. Our study suggests that wild populations may commonly experience multiple and variable selection pressures that can favour seemingly puzzling trait variation. We highlight the need to quantify variation in selection pressures and investigate how such variation, especially the unpredictable aspects, shapes prey traits.

We surveyed the genetic structuring of 12 Schistocephalus solidus tapeworm populations from Vancouver Island (BC, Canada) using ddRAD sequencing and compared it to that of their threespine stickleback fish hosts. There were small but mostly significant genetic differences among the tapeworm populations. PCA results separated the populations by watershed (from the lakes where the tapeworms were collected), but we could not determine if the genetic structures seen were due to discrete models (i.e. watershed) or to a continuous model (i.e. isolation by distance). However, the tapeworm genetic differences were significantly smaller (P < 0.001) than those of the fish, which indicates that the parasite disperses more readily than their fish hosts.

Evolution is a foundational framework for understanding biology, yet it remains challenging to teach and learn. Game-based learning may offer one way to support evolution instruction by helping students visualize abstract, dynamic, and difficult-to-observe processes. In this study, we interviewed undergraduate biology instructors to examine how they evaluated video games as potential tools for evolution education, including which topics they perceived as most challenging for students. We found that instructors were broadly open to using video games for evolution instruction, particularly when games could support population-level reasoning, evolutionary mechanisms, speciation and phylogeny, quantitative reasoning, and long time scales. Instructors also emphasized that games must be scientifically accurate, accessible, and aligned with course learning goals. This study contributes an instructor-centered perspective to evolution education and game-based learning research by identifying how instructors connect persistent student learning challenges with potential design priorities for educational video games. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=113 SRC="FIGDIR/small/736808v1_ufig1.gif" ALT="Figure 1"> View larger version (24K): org.highwire.dtl.DTLVardef@175ce4corg.highwire.dtl.DTLVardef@13ae260org.highwire.dtl.DTLVardef@e44aceorg.highwire.dtl.DTLVardef@1eb1ef1_HPS_FORMAT_FIGEXP M_FIG C_FIG

Numerous species of animals alter their behavior in response to increasing competition. To do so, they must possess the ability to detect the presence and density of interspecific competitors. We studied the role of semiochemicals released by increasing densities of larval Culiseta longiareolata Macquart on female oviposition habitat selection in two sets of field mesocosms. Similarly to C. longiareolata larvae, subordinate Culex laticinctus Edwards are periphyton grazers who dwell in rain-filled pools in the Mediterranean region. We show that C. laticinctus females oviposited significantly less in mesocosm pools that were treated with crowding signals originating from C. longiareolata larvae. In a second field experiment, we placed a similar number of larvae directly inside the 50 L mesocosms. These low-density mesocosms did not affect C. laticinctus oviposition but were attractive to conspecific oviposition. These results increase our understanding of the females ability to detect species-specific signals indicating increased larval competition. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=71 SRC="FIGDIR/small/587456v1_ufig1.gif" ALT="Figure 1"> View larger version (17K): org.highwire.dtl.DTLVardef@1b6cb56org.highwire.dtl.DTLVardef@1dfb77aorg.highwire.dtl.DTLVardef@86c531org.highwire.dtl.DTLVardef@1fc26b3_HPS_FORMAT_FIGEXP M_FIG C_FIG

Practical approaches have become a standard in many scientific disciplines, including population genetics. By analyzing properly selected datasets, the students can calculate parameters and draw conclusions about genetic diversity, differentiation and evolution of populations with higher efficiency than if based exclusively on theoretical lessons. However, preparing the appropriate datasets is a hard task and a wrong selection can spoil a well-aimed practice. Here we present SO_SCPLOWIMC_SCPLOWHO_SCPLOWYBC_SCPLOW 2, a software tool specifically intended to ease the full understanding of evolutionary forces by the students and to help the teacher to prepare adequate datasets and examples for the practices. It simulates the course of a mixed population under user-defined reproductive and evolutionary conditions. Outputs can be easily adapted for downstream analysis with other popular tools as GO_SCPLOWENC_SCPLOWAO_SCPLOWLC_SCPLOWEO_SCPLOWXC_SCPLOW or SO_SCPLOWTRUCTUREC_SCPLOW. Thus, SO_SCPLOWIMC_SCPLOWHO_SCPLOWYBC_SCPLOW 2 is very suitable for project-based-learning approaches: students can produce their own datasets in different scenarios of genetic drift, migration, selective advantage, reproductive success... Additionally, SO_SCPLOWIMC_SCPLOWHO_SCPLOWYBC_SCPLOW 2 is the only simulation software available to date providing traceable pedigrees of individuals, being therefore very convenient for preparing datasets for parentage analysis, spatial genetic structure or conservation genetics study cases. Satisfactory results from its ongoing utilization in higher education and research are reported.

There is a clear and concrete need for greater quantitative literacy in the biological and environmental sciences. Data science training for students in higher education necessitates well-equipped and confident instructors across curricula. However, not all instructors are versed in data science skills or research-based teaching practices. Our study sought to survey the state of data science education across institutions of higher learning, identify instructor needs, and illuminate barriers to teaching data science in the classroom. We distributed a survey to instructors around the world, focused on the United States, and received 106 complete responses. Our results indicate that instructors across institutions use, teach, and view data management, analysis, and visualization as important for students to learn. Code, modeling, and reproducibility were less valued by instructors, although there were differences by institution type (doctoral, masters, or baccalaureate), and career stage (time since terminal degree). While there were a variety of barriers highlighted by respondents, instructor background, student background, and space in the curriculum were the greatest barriers of note. Interestingly, instructors were most interested in receiving training for how to teach code and data analysis in the undergraduate classroom. Our study provides an important window into how data science is taught in higher education as well as suggestions for how we can best move forward with empowering instructors across disciplines.

The ability to use data and evidence as the basis for scientific reasoning is a critical skill that undergraduate students must learn to successfully transition into science careers. There is a need for pedagogical tools that promote the development of science process skills and reduce barriers to implementation in the classroom. PubNavigator (www.pubnavigator.com) is a science communication platform that shares the findings of primary literature using accessible language and features biographical information about the authors. This research assesses the utility of PubNavigator as an undergraduate teaching resource. We analyzed responses to an assignment prompting discussion of PubNavigator articles in an asynchronous online discussion forum in an introductory biology course. We conducted thematic analysis guided by the evidence-based reasoning framework to identify evidence of science reasoning and interactive enagement. We found evidence that the PubNavigator assignment elicited engagement in scientific reasoning. Students who demonstrated higher levels of engagement with the assignment also demonstrated higher levels of science reasoning in their discussion of the articles. Our findings support PubNavigator as an undergraduate teaching tool that can be used to promote science reasoning and engagement in introductory biology. We provide recommendations for implementation to instructors interested in integrating PubNavigator activities into their courses.

Course-based Undergraduate Research Experiences (CUREs) are emerging as a means to engage large numbers of undergraduate students in meaningful inquiry-based research activities. We describe here a simple laboratory exercise as part of an undergraduate genetics course that illustrates the contributions of oncogenes and tumor suppressors to the formation of neoplasms in an invertebrate model system. In addition, students were challenged to investigate whether flies reared on a diet containing a variety of additives display a higher number of invasive tumors in the larval abdomen. The goal of the exercise was to (i) familiarize students with the multigenic origin of the cancer phenotype, to (ii) introduce some of the fundamental molecular cancer hallmarks, and to (iii) highlight the significance of invertebrate model systems in biomedical research. Furthermore, (iv) students learn to execute a molecular test for transgenic produce and (v) apply statistical tools to test a simple hypothesis. We evaluated student learning and changes in opinions and attitudes relating to environmental versus genetic causes of cancer and several common misconceptions using a questionnaire before and after completing the exercise. Overall, significant improvements in the rate of factually correct responses and reductions in uncertainty were demonstrated. Although resistance to change was apparent in regard to identifying some risk factors, there was clear learning and understanding of the core concepts of carcinogenesis and the utility of basic research with model organisms.

Freshwater mussels in western North America are threatened by water diversions, climate change, loss of required host fish, and other factors, and have experienced marked decline in the past several decades. All four of the primary lineages (potentially species) of freshwater mussels in the western U.S. and Canada are widespread and have somewhat generalist host fish requirements. Of these lineages, perhaps the most poorly understood and of greatest conservation concern is Gonidea angulata (Rocky Mountain ridged mussel). Gonidea is a monotypic genus occurring only in the western continental U.S. and southern Canada. Here we describe the patterns of genetic variation across the species range, including several populations in the Okanagan Valley at the northern edge of the range. We detected only ten mitochondrial cytochrome oxidase I haplotypes, three of which ere commonly found across major hydrologic basins, and the remainder of which were basin-specific variants. Haplotypes differed by a maximum of 5 of 537 nucleotides. New microsatellite loci were developed for G. angulata as a part of this study. Data from these microsatellite loci indicated that the population in the Chehalis River, Washington, was distinct from other locations, and that the Okanagan lake population was somewhat diverged from the remaining populations in the Columbia River and Klamath Lake. Only low levels of inbreeding were detected, in contrast to previous findings in Margartifera falcata, suggesting that hermaphroditism is not common. The population with the least diversity, according to microsatellite data, was the northernmost known population in Okanagan Lake We discuss the biogeographic and conservation implications of our findings.

Observations made from papers submitted to preprint servers, and the speculation of editors on social media platforms, suggest that women are submitting fewer papers to scholarly journals than are men during the COVID-19 pandemic. Here I examine whether submissions by men and women to six ecology journals (all published by the British Ecological Society) have changed since the start of COVID disruptions. At these six ecology journals there is no evidence of a decline in the proportion of submissions that are authored by women (as either first or submitting author) since the start of the COVID-19 disruptions; the proportion of papers authored by women in the post-COVID period of 2020 has increased relative to the same period in 2019, and is higher than in the period pre-COVID in 2020. There is also no evidence of a change in the geographic pattern of submissions from across the globe.Competing Interest StatementCharles Fox is Executive Editor of Functional Ecology, one of the journals that contributed data for the analyses presented in this paper.View Full Text

Unionoid freshwater mussels (Bivalvia: Unionidae) are free-living apart from a brief, obligately parasitic, larval stage that infects fish hosts and gravid female mussels have evolved a spectrum of strategies to infect fish hosts with their larvae. In many North American species, this involves displaying a mantle lure: a pigmented fleshy extension that acts as an aggressive mimic of a host fish prey, thereby eliciting a feeding response that results in host infection. The mantle lure of Lampsilis fasciola is of particular interest because it is apparently polymorphic, with two distinct primary lure phenotypes. One, described as "darter-like", has "eyespots", a mottled body coloration, prominent marginal extensions, and a distinct "tail". The other, described as "worm-like", lacks those features and has an orange and black coloration. We investigated this phenomenon to 1) confirm that it is a true polymorphism; 2) investigate its ecological persistence; 3) identify the range of putative model species targeted by this mimicry system within a river drainage; 4) determine whether the mantle lure polymorphism includes a behavioral component. Detection of within-brood lure variation and within-population phylogenomic (ddRAD-seq) analyses of individuals bearing different lures confirmed that this phenomenon is a true polymorphism. It appears stable over ecological timeframes: the ratio of the two lure phenotypes in a River Raisin (MI) population in 2017 was consistent with that of museum samples collected at the same site 6 decades earlier. Within the River Raisin, four main "darter-like" lure motifs visually approximated four co-occurring darter species (Etheostoma blennioides, E. exile, E. microperca, and Percina maculata) and the "worm-like" lure resembled a widespread common leech, Macrobdella decora. Darters and leeches are typical prey of Micropterus dolomieui (smallmouth bass), the primary fish host of L. fasciola. In situ field recordings were made of the L. fasciola "darter" and "leech" lure display behaviors, in addition to the non-polymorphic lure display of co-occurring L. cardium. Despite having putative models in distinct phyla, both L. fasciola lure morphs have similar display behaviors that differ significantly from that of sympatric L. cardium individuals. We conclude that the L. fasciola mantle lure polymorphism does not include a behavioral component. Discovery of discrete within-brood inheritance of the lure polymorphism implies potential control by a single genetic locus and identifies L. fasciola as a promising study system to identify regulatory genes controlling a key adaptive trait of freshwater mussels.

The Sonoran Desert Toad (Incilius alvarius) is the only animal known to secrete the psychedelic compound 5-MeO-DMT as a chemical defense, but the source of 5-MeO-DMT in I. alvarius remains unknown. Some amphibians endogenously produce chemical defenses while others acquire them from specialized diets. In this study we analyzed toxin gland secretions and diet profiles from wild I. alvarius and sympatric anurans from native and urban habitats around Tucson, Arizona to explore possible links between diet and 5-MeO-DMT production. All I. alvarius secreted high concentrations of 5-MeO-DMT, whereas other sympatric toads did not. The diet of I. alvarius was similar to that of sympatric anurans, indicating that I. alvarius does not exhibit relative dietary specialization. Slight dietary differences between I. alvarius in native and urbanized habitats were observed. Taken together, these lines of evidence suggest that diet is not directly linked to 5-MeO-DMT production, and support the alternative hypotheses that Sonoran Desert toads synthesize 5-MeO-DMT endogenously or via a microbial symbiont.