118 research outputs found

    Dodge, Duck, Dip, Dive & Dependence: Using Dodgeball to Explore Frequency Dependent Selection

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    The term frequency dependence describes scenarios in which the likelihood of an event occurring is strongly tied to how common a particular trait is. Understanding frequency dependence is key to understanding numerous biological processes relevant to evolution by natural selection, such as predation, mimicry, disease, and effective vaccinations. We use dodgeball to demonstrate frequency dependent selection in a hypothetical predator–prey community, and provide possible extensions into other topics. This activity can be used with biology students in high school through upper-level undergraduate courses

    Investigating Prior Mentoring Experiences of Medical Students and Its Perceived Benefits

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    Successful mentoring relationships allow mentees to gain the confidence and knowledge they need to reach their goals, but students from populations generally underrepresented in science and health fields have been shown to receive less mentorship than their well-represented peers. In highly competitive processes, like medical school admissions, mentoring may be particularly valuable. We investigated the prior mentoring experiences of medical students and whether their perceptions of mentoring differed based on their mentoring goals or demographics (race/ethnicity, gender identity, household income, or parental highest level of education) through surveys and interviews of medical students from three different institutions. These medical students had widely participated in mentoring, though student race and household income impacted their access to medical professionals to serve as informal mentors. Medical students shared the same gender identity as their mentor more often than would be expected under the null hypothesis. Students reported having both career and psychosocial goals for mentoring, and there was a positive association between the strength of the mentees’ goals for mentoring and the number of formal mentors the mentees had. These respondents viewed mentoring as having provided them with both career and psychosocial benefits. Mentoring programs for aspiring medical students may benefit from focusing on both career and psychosocial functions to maximize the benefits of mentoring for students from diverse backgrounds

    Nonconsumptive effects in a multiple predator system reduce the foraging efficiency of a keystone predator

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    Many studies have demonstrated that the nonconsumptive effect (NCE) of predators on prey traits can alter prey demographics in ways that are just as strong as the consumptive effect (CE) of predators. Less well studied, however, is how the CE and NCE of multiple predator species can interact to influence the combined effect of multiple predators on prey mortality. We examined the extent to which the NCE of one predator altered the CE of another predator on a shared prey and evaluated whether we can better predict the combined impact of multiple predators on prey when accounting for this influence. We conducted a set of experiments with larval dragonflies, adult newts (a known keystone predator), and their tadpole prey. We quantified the CE and NCE of each predator, the extent to which NCEs from one predator alters the CE of the second predator, and the combined effect of both predators on prey mortality. We then compared the combined effect of both predators on prey mortality to four predictive models. Dragonflies caused more tadpoles to hide under leaf litter (a NCE), where newts spend less time foraging, which reduced the foraging success (CE) of newts. Newts altered tadpole behavior but not in a way that altered the foraging success of dragonflies. Our study suggests that we can better predict the combined effect of multiple predators on prey when we incorporate the influence of interactions between the CE and NCE of multiple predators into a predictive model. In our case, the threat of predation to prey by one predator reduced the foraging efficiency of a keystone predator. Consequently, the ability of a predator to fill a keystone role could be compromised by the presence of other predators

    Understanding undergraduate students’ eHealth usage and views of the patient-provider relationship

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    © 2022 Reyes, Vance-Chalcraft. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.eHealth has grown exponentially alongside technology and has become widely accessed by some populations, but little is documented about how undergraduate students use eHealth or perceive their eHealth literacy. As access to online information and non-traditional options for interacting with providers has increased, patient views of the provider-patient relationship may also be changing. This study evaluates how frequently undergraduates use eHealth, how they perceive their ability to use eHealth appropriately, and how they view their patient-provider relationships. A mixed methods approach was used to address the research questions, with quantitative data from a survey and qualitative data from follow-up interviews of twelve of the survey respondents. The survey was distributed to over 650 undergraduate students in introductory biology laboratory courses for students of all fields of interest at one university. Based on 527 survey responses and 12 interviews, students reported commonly using eHealth but being skeptical of telehealth appointments. Although students generally felt capable of finding and interpreting eHealth sources, they were not strongly confident in their ability to do so. Use of eHealth was not seen as altering the patient-provider relationship, but students expressed a desire for their physician to act more as a counselor or advisor than a guardian. Students from minority populations were more likely to use eHealth in comparison to their peers. In addition, student comfort with their provider differed by race and ethnicity, as well as whether they shared the same gender identity as their provider. This research highlights how undergraduate students, who are often making medical decisions for themselves for the first time as adults, access health information and view the patient-provider relationship differently than the traditional guardian or paternalistic model. In addition, having diverse, culturally competent medical providers are critical for students to develop the relationship with their provider that they desire.ALS PLOS ONE institutinal accoun

    Across-ecoregion analysis suggests a hierarchy of ecological filters that regulate recruitment of a globally invasive fish

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    Aim -- Even successful invaders are abundant only in a fraction of locales they inhabit. One of the main challenges in invasion ecology is explaining processes that drive these patterns. We investigated recruitment of a globally invasive fish, common carp (Cyprinus carpio), across three ecoregions to determine the role of environmental characteristics, predatory communities and propagule pressure on the invasion process at coarse and fine spatial scales. Location -- Lakes across Northern Forest, Temperate Forest and Great Plains ecoregions of North America. Methods -- We used data from 567 lakes to model presence or absence of carp recruitment using environmental conditions (lake clarity, area, maximum depth), native predatory fishes (micropredators, mesopredators, large predators) and propagule pressure (abundance of adult carp). We formed a set of alternative models and evaluated their support using an information theoretic approach. Once most supported models were identified, we used classification tree to determine how variables included in these models interacted to affect carp recruitment. Finally, we conducted a field experiment to test the predictions of the classification tree analysis. Results -- Carp recruitment was strongly regulated by processes associated with water clarity, which appeared to function as a broad-scale ecological filter. Carp were unlikely to recruit in clear, oligotrophic lakes (Secchi depth \u3e 2 m) despite the presence of adults in many such systems. Recruitment was more likely to occur in regions with turbid lakes, but abundant micropredators could inhibit it there. Main conclusions -- Carp recruitment and invasions across large geographic areas are attributable to a two-layer ecological filter with lake clarity/productivity acting as a coarse-scale filter and micropredators acting as a fine-scale filter. This two-layer filter might explain the complex patterns of carp invasions among and within different ecoregions. Ecological filters may also explain the success of other aquatic invaders that show similarly patchy spatial distribution patterns

    Resource Heterogeneity Moderates the Biodiversity-Function Relationship in Real World Ecosystems

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    Numerous recent studies have tested the effects of plant, pollinator, and predator diversity on primary productivity, pollination, and consumption, respectively. Many have shown a positive relationship, particularly in controlled experiments, but variability in results has emphasized the context-dependency of these relationships. Complementary resource use may lead to a positive relationship between diversity and these processes, but only when a diverse array of niches is available to be partitioned among species. Therefore, the slope of the diversity-function relationship may change across differing levels of heterogeneity, but empirical evaluations of this pattern are lacking. Here we examine three important functions/properties in different real world (i.e., nonexperimental) ecosystems: plant biomass in German grasslands, parasitism rates across five habitat types in coastal Ecuador, and coffee pollination in agroforestry systems in Indonesia. We use general linear and structural equation modeling to demonstrate that the effect of diversity on these processes is context dependent, such that the slope of this relationship increases in environments where limiting resources (soil nutrients, host insects, and coffee flowers, respectively) are spatially heterogeneous. These real world patterns, combined with previous experiments, suggest that biodiversity may have its greatest impact on the functioning of diverse, naturally heterogeneous ecosystems

    Role of supplemental foods and habitat structural complexity in persistence and coexistence of generalist predatory mites

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    Variation in the strength of intraguild predation (IGP) may be related to habitat structural complexity and to additional resources outside the narrow predator-prey relationship. We studied the food web interactions on grape, which involves two generalist predatory mites. We evaluated the effects of grape powdery mildew (GPM) as supplemental food, and habitat structural complexity provided by domatia. Our findings suggest that structural and nutritional diversity/complexity promote predatory mite abundance and can help to maintain the beneficial mites - plants association. The effect of these factors on coexistence between predators is influenced by the supplemental food quality and relative differences in body size of interacting species
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