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Item Curriculum design and assessment: the development of a nonmajor biology course-based undergraduate research experiences and its effects on students and instructors(North Dakota State University, 2024) Falkner, WilliamThe goals of nonmajor science education are to improve scientific literacy and produce pro-science attitudes. Together, these goals are expected to improve an individual’s ability to make evidence-based decisions based on newer understandings of the natural world as well as developing technologies. In a post-COVID-19 world, public understanding of science was brought to the forefront for public health but were also challenged by a deluge of misinformation to obfuscate these goals. General education science courses represent the last formal experience for our populace. Following a learning-science-by-doing-science approach, this dissertation describes the development, implementation, and assessment of a course-based undergraduate research experience (CURE) for nonmajor science students. The first objective of this dissertation was to review the outcomes and design elements of published CUREs. Through a systematic review of Biology-based CURE literature, several content, skill, and affective-based outcomes are identified resulting from eight proposed design elements. The second objective was to outline and highlight the decision-making process when designing a CURE for nonmajors. Here, historical perspectives on course design, both general and science-specific, are described and applied along with findings from the first objective to design a CURE for nonmajor biology students. The third objective was to survey graduate teaching assistants (GTAs) that instructed this nonmajor CURE to identify GTA benefits and challenges. Findings indicate that GTAs found CUREs to be beneficial to their current and future works and strongly believed this type of approach to nonmajor education is preferable to expository lab design. The final objective was to assess student scientific literacy and science attitudes after engaging with a CURE. Based on two surveys using a pre/post design, there were no significant differences between different laboratory course designs for neither literacy nor attitudes and only found some support between the association of scientific literacy and science attitudes. This dissertation demonstrates the complexity of cradle-to-grave course design, the difficulty in measuring large constructs such as scientific literacy and science attitudes, and implications for future evidence-based course design.Item Emotion regulation moderates the prospective association between ERN and anxiety in early adolescence: An age-specific moderation of cognitive reappraisal but not expressive suppression(North Dakota State University, 2024) Tan, Jaron Xe YungThe increasing prevalence of anxiety problems during adolescence underscores the importance of a better understanding of the development of anxiety. While past research has highlighted a link between error responsivity, indexed by error-related negativity (ERN), and youth anxiety, the role of emotion regulation in the ERN-anxiety relationship remains unclear. We conducted a two-wave study with 115 healthy nine-12-year-olds, and found that expressive suppression (ES), an important emotion regulatory strategy, moderates the ERN-anxiety association. A larger T1 ERN predicted heightened T2 anxiety symptoms in those with higher ES. Interestingly, the moderating effect of cognitive reappraisal (CR), another important emotion regulatory strategy, on the ERN-anxiety association was age-dependent; in older youths, the association between T1 ERN and T2 symptoms was significant only for those with lower CR. These findings offer novel insights into the differential age-related patterns in the moderating effects of emotion regulation, and inform future emotion intervention studies for youths.Item Rural Youth's Enrollment in a Stem Summer Camp: A Comparison Between In-Person and Take-Home Experiences(North Dakota State University, 2021) Milbrath, Madison RenaThe utilization of informal STEM education opportunities has been well established as a way to supplement and support formal STEM education learning. Many of the studies confirming this were completed in urban settings. Recently there have been calls to better our understanding of rural populations and their interactions with informal STEM education. This study analyzed the registration records of youth in an informal STEM education experience as well as survey responses from the youths’ parents/guardians. This was done in an attempt to understand if rurality impacts participation in an in-person STEM education experience compared to a take-home STEM education experience. Additional work looking at survey responses attempted to find other predictors or indicators that could be reasons for participation associated with rural populations.Item Establishing and Characterizing Patient-Derived Breast Cancer Cell Lines(North Dakota State University, 2022) Mohammadi, Farid SolaymaniCommercial cancer cell lines have long been extensively used as an important platform to study cancer. They have contributed to a plethora of discoveries in the field of cancer research. However, there are limitations with using these cell lines, such as induced mutations over the long-term in vitro culture. These mutations cause incorrect exhibition of the in vivo characteristics of the cancer cells. Here, we focused on establishing Patient-derived breast cancer cell lines and attempted to characterize them in terms of several biomarkers that are shown to be overexpressed in breast cancer cells. Patient-derived breast cancer cell lines are more reliable tools to study the molecular and cellular processes taking place in vivo, since they are freshly isolated from the tumor biopsy and do not undergo induced immortalization. We explored the CK19, Ki67, vimentin, EpCAM, E-cadherin, and N-cadherin expression in three successfully established patient-derived breast cancer cell lines.Item The Conservation of Variation in Gryllodes sigillatus and Closely Related Cricket Species(North Dakota State University, 2020) Dalos, Jeremy DavidThe ability to adjust behaviors to a particular environment has been well documented across taxa. Our understanding of behavioral plasticity is largely based on experiments in which individuals have a single exposure to an environment. Observed behavioral changes are then traditionally measured in small windows of responsiveness in a single population or species. In this project I investigated the effects of prolonged exposure to predator cues in Gryllodes sigillatus and also tested for the presence of trans-generational effects of this prolonged exposure. I found there were no differences in anti-predator behaviors when measured in subsequent assays compared to control individuals. These results were paired with a comparison of differences in average expressions of behaviors, differences in variances, and behavioral correlations of five closely related cricket species, including G. sigillatus. Our results showed that species differ in average behaviors and plasticity but did not significantly differ in behavioral correlations.Item Plant Phenological Responses to Climate Change in the Northern Great Plains(North Dakota State University, 2010) Dunnell, Kelsey LiannClimate change has been associated with shifts in phenological events which could be disrupting evolved species relationships. The current first flowering times of plants were compared to historical data in the Red River Valley. This gave insight as to what effects climate change is currently having on species in this area. By merging climate variable data from the same time period it was possible to correlate first flowering dates with climate variables for that specific year. Variation in plant flowering times was analyzed over the century to better understand potential ecological consequences of climate change. First flowering times were found to have shifted since previously recorded. The lengthening growing season in the Red River Valley as a result of climate change has resulted in significant shifts in the timing of plant life cycles. The second study used an experimental approach to test the effects of warming on plant species in the tallgrass prairie. Measuring phenological and species composition responses to the temperature changes showed evidence that increasing air temperatures are leading to earlier flowering. There was also a significant increase in species richness. The results of both studies conclude that climate change has the potential to impact the plant community by shifting phenological responses in the tallgrass prairie in the Northern Great Plains.Item From Alcelaphus to Zapus: Conservation of Modern Mammalian Populations(North Dakota State University, 2015) Preston, Kathryn AnneConservation priorities are increasingly important in the face of modern human activities. Anthropogenic activities such as deforestation, pollution, and climate change have negative impacts on all vertebrates. In chapter 1, I examine whether there are relationships among density dependence, population size variability, and extinction risk in mammals to see whether these parameters are indicative of population health. Also included were analyses of how body mass and age to maturity affect those three measures. On a smaller, more local scale, I asked questions regarding biodiversity of small mammals in a highly fragmented environment, the tallgrass prairie. In chapter 2, I examined how cattle grazing impacts small mammal biodiversity in the Sheyenne National Grassland on a short term, season-long scale. By understanding the interaction of large herbivores, vegetation height, and small mammals, appropriate measures can be taken to conserve this rare habitat properly, without sacrificing biodiversity.Item Environmental Impacts on Behavior and Personality in the Caviomorph Rodent, Octodon degus(North Dakota State University, 2019) Johnson, Nicholas EdwinEnvironmental factors can have large impacts in shaping the way that animals behave. Biotic elements, such as predators and conspecifics that individuals interact with, are two environmental factors that animals may encounter on a regular basis. Here, we present the results of two studies examining the relationship of these biotic factors to behavior and personality in the degu (Octodon degus), a social rodent species endemic to central Chile. We found that long-term experimental isolation from predators has not impacted behavior, as indicated by an open field test in this species. We also found that social groups in this species do not adhere to either conformity or social niche specialization expectations with regard to personality, as determined in open field tests. These results raise further questions as to the mechanisms that govern behavior, as well as how personality evolved and is maintained in natural populations.Item An Investigation of Student Understanding and Acceptance of Evolution(North Dakota State University, 2021) Harding, Rachel Leigh SalterEvolution is central to biology education and yet, it is often one of the most misunderstood and controversial topics that biology educators must teach. Research spanning the last four decades has shown that students continue to struggle, even with direct instruction, to understand the process of evolution by natural selection. In my first chapter, I found that students enrolled in non-majors geology course did not increase in their understanding of evolution, even after instruction. This followed similar findings from research occurring over 30 years in the past. Discipline-based education researchers have theorized that students’ persistent difficulties understanding evolution may stem from the conceptual challenges inherent to complex biological systems. To meet the needs of biology instructors, I developed a new teaching tool, a rapid response rubric (3R: Evolution), to provide more opportunities for formative assessment and feedback in large-enrollment courses. I found the 3R: Evolution provided direct and actionable feedback, allowing students to modify their understanding of evolution in large-enrollment courses and exhibit large increases in their knowledge from pre- to post-assessment. However, knowledge of evolution is not the only challenge to biology education: students must also accept evolution. A lack of evolution acceptance can emerge from various social, cultural, and epistemological factors including religiosity and regional impacts, knowledge of the nature of science, openness to experience, and evolution exposure. In this work, I present a path analysis to illuminate the direct causal relationships from these individual factors to evolution acceptance. I found that while religiosity was the largest casual predictor of acceptance, the other chosen factors, including knowledge of evolution, were all significant predictors of evolution acceptance. Even though evolution remains a difficult topic, this work shows that students can increase both their understanding and acceptance of evolution, using new curriculum and increasing exposure to evolution content across their school career.Item Physiological Mechanisms Underpinning Growth and Aging in Wild Birds(North Dakota State University, 2019) Sirman, Aubrey ErinLife-history trade-offs have been well-documented within the literature through correlational and experimental studies. However, the physiological mechanisms underlying these trade-offs are less understood. Currently, there is great interest in shared mechanisms, specifically endocrine mechanisms, that might underlie the variation in life-history traits. Insulin-like growth factor-1 (IGF-1) may be one shared mechanism that is particularly important. IGF-1 is a metabolic hormone that is part of a highly conserved insulin-signaling pathway known to influence multiple life-history traits including growth and longevity across taxa, however, little is known about these trade-offs outside of laboratory populations. This dissertation focuses on the role of IGF-1 as a hormonal mechanism underlying the life-history trade-off between growth and aging in wild birds. While the causes of aging are not fully understood, telomere dynamics (length and change in length) are a potentially important mechanism underlying lifespan. To investigate the role of IGF-1 as a hormonal mechanism underlying the life-history trade-off between growth and aging in Franklin’s gulls (Leucophaeus pipixcan) and house sparrows (Passer domesticus). In Franklin’s gulls, dietary restriction reduced growth rate and IGF-1 levels but did not impact telomere dynamics. However, there was a significant negative correlation between IGF-1 levels and telomere length at the end of the post-natal growth period. In house sparrows, we found that nestling growth rates varied with respect to year, but IGF-1 levels did not. Telomere dynamics were not related to growth rates or IGF-1 levels, suggesting that during post-natal growth nestlings may be able to mitigate or even delay costs to later life stages. Finally, when exogenous IGF-1 was administered to house sparrow nestlings during the post-natal growth period, nestling growth was impacted but only in some years. Exogenous IGF-1 increased growth and final mass in 2016 and final mass in 2018. There was a trend suggesting experimental birds had shorter telomeres in 2016. Similarly, in 2018, experimental birds had significantly shorter telomeres than control birds. These effects were not observed in 2017, suggesting that trade-offs between growth an aging might only be visible under certain environmental conditions, which may vary with respect to year.