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Multidecadal Data Demonstrate the Role of Climate and Natural History Traits in Shaping Butterfly Phenology
Get PDFClimate change is transforming the natural world, altering the timing of key events in the lives of plants and animals, such as when flowers bloom or when butterflies take flight. These timing changes, known as phenology shifts, can disrupt ecosystems and species interactions, creating ripple effects through food webs and biodiversity. While scientists have studied these shifts for decades, much of the focus has been on simple metrics, like the first or last day a butterfly is seen flying each year. However, these measures do not tell the whole story of how climate change is impacting the entire flight season or even why different species respond in different ways. In this study, we used decades of butterfly observations from five mountain sites in California to explore how climate affects butterfly flight seasons. By examining 135 butterfly species across sites ranging from low to high elevations, we looked at how temperature and precipitation influence their flight periods. We found that climate has complex effects on butterflies. Warmer daytime spring temperatures made butterflies fly earlier across all elevations, while snowy winters delayed their activity in areas with a substantial amount of snowfall. Even small changes in nighttime spring temperatures significantly shifted the timing of their flight seasons. Interestingly, not all species responded to climate in the same way. We saw large differences in how climate affected butterflies. Differences in their natural history traits, like how many generations a species has per year (voltinism), what types of plants their caterpillars feed on (diet breadth), and the life stage at which they survive the winter (overwintering stage) do not fully explain these variations in the effect of climate. Our research highlights the need to study the full flight season of butterflies, not just isolated moments, to better understand how they are being impacted by climate change. These insights can help conservationists make smarter decisions about protecting butterflies and the ecosystems they support, ensuring we’re better prepared to address the challenges of a warming world
Ecological Interactions of Cougars, Deer, And Wild Pigs in the Central Coast Range, California
Get PDFWild pigs are an introduced species in the Americas that negatively affect ecosystems in many ways. Previous research has documented their negative effects on water quality and vegetation and their potential to spread disease among wildlife, domestic animals, and humans. However, how wild pigs affect predator-prey interactions between native wildlife has received little attention. This research explores multiple interactions between wild pigs, a native predator (cougars), and a native prey (black-tailed deer). First, I studies cougar diet to understand how frequently pigs are used as prey. During this project, I also placed wildlife cameras at cougar killed prey to monitor scavenging behavior by pigs. Second, I monitored tagged pigs to measure their survival rates and determine causes of mortality. Finally, I evaluated the potential for competition for resources between pigs and deer to determine if deer are negatively affected by pigs. I observed that pigs, especially young pigs, are an important alternative prey item for cougars, but that native deer remain the primary prey. Pigs also regularly scavenged at cougar killed prey and rarely stole kills from cougars. Pig survival was similar to other areas in the US, and cougars were only a cause of mortality for juvenile and subadult pigs, suggesting that adults are not vulnerable to cougar predation. Finally, I observed high overlap in space use, activity periods, and diet of deer and pigs, but did not find any negative effects of pigs on deer reproduction or body condition. This suggests pigs have minimal negative effects on deer through competition. Combined, these results provide a clearer picture of how pigs affect the native cougar-deer system through multiple interactions with each species
Assessing Canopy Features, Its Shading Factor, And Their Influence in the Estimation of Evapotranspiration in Almond Orchards Using UAS Information and the Two-Source Energy Balance Model
Get PDFThis study explored how canopy biomass and shadows affect evapotranspiration (ET) estimates, a crucial factor for irrigation management in almond orchards in California’s Central Valley. Data from 24 drone flights over three almond plots in 2021 and 2022 were analyzed using the Two-Source Energy Balance (TSEB) model, combined with meteorological data from EC-towers. The study found that filtering out shadows improved ET estimation, particularly in young orchards, and identified the importance of using new Leaf Area Index (LAI) models for better accuracy. This research is part of the T-REX initiative, which integrates drone and ground-based data to enhance water use efficiency in almond orchards
Insights From Diverse Environments: Investigating the Fate and Transport of Semivolatile Organic Contaminants in Alpine, Arctic, And Arid Regions
Get PDFThis dissertation investigates the fate and transport of pollutants through four field-based studies in a diverse array of environments. These pollutants travel through the atmosphere and end up in places far from their original sources. In this work I explore how chemical properties of the pollutants and the environmental processes that are present change the way the pollutants travel through the environment. In the first study, pollutants from car engines were quantified in the vegetation along transects in three alpine valleys. Using these measurements, I investigated how the chemical properties of the pollutants impacted their interplay with wind systems in the valleys. Next, the atmospheric transport of pollutants from an urban area into a protected alpine wilderness was investigated. In this study, I show that the temperature changes in alpine areas impact the deposition of these pollutants into the soil. In an even more remote area, I investigated the behavior of pesticides in an Arctic lake. By measuring these pesticides in air and water, I was able to demonstrate that springtime melting releases a pulse of pesticides. Lastly, in a very different lake system, I measured pollutants in dust that is blowing off the dry lakebed of the Great Salt Lake. These pollutants were found at higher levels in the dust than in the underlying lakebed. Together, these studies demonstrate the ways that pollutant fate in the environment differs depending on their chemical properties and the environmental processes at play
Characterizing Teacher Support of Debugging With Physical Computing: Debugging Pedagogies in Practice
Get PDFObjectives. Physical computing systems are increasingly being integrated into secondary school science and STEM instruction, yet little is known about how teachers, especially those with little background and experience in computing, help students during the inevitable debugging moments that arise. In this article, we describe a framework, comprising two dimensions, for characterizing how teachers support students as they debug a physical computing system called the Data Sensor Hub (DASH). The DASH enables students to program sensors to measure, analyze, and visualize data as they engage in science inquiry activities
Participants. Five secondary school teachers implemented an inquiry-oriented instructional unit designed to introduce students to working with the DASH as a tool for scientific inquiry.
Study Method. Findings drew on video analysis of the teachers’ classroom implementations of the unit. A review of the data corpus led to the selection of 23 moments where the teachers supported an individual or small groups of students engaged in debugging. These moments were analyzed using a grounded perspective based on Interaction Analysis to characterize the teachers’ varied interactional approaches.
Findings. Our analysis revealed how teachers’ moves during debugging moments fell along two dimensions. The first dimension characterizes teachers’ positioning during the debugging interactions, ranging from a positioning for teacher understanding to a positioning for student understanding of the bug. The second dimension characterizes the inquiry orientation of the teachers’ questions and guidance, ranging from focusing on the debugging process to focusing on the product—or fixing the bug. Further, teachers’ moves often fell along different points on these dimensions given nuances in the instructional context.
Conclusions. The framework offers a first step toward characterizing teachers’ debugging pedagogy as they support students during debugging moments. It also calls attention to how teachers do not necessarily need to be programming experts to effectively help students learn independent and generalizable debugging strategies. Further, it illustrates the variety of expertise that teachers can bring to debugging moments to support students learning to debug. Finally, the framework provides implications for the design of professional learning and supports for teachers as they increasingly are asked to support students in computing—and debugging—activities across a range of disciplines
Correlation Between Maximal Eccentric and Isometric Multi-Joint Lower-Extremity Strength and Vertical Jumping Performance in Young Adults
Get PDFMaximal eccentric (MES) and isometric (MIS) muscle strength may enhance vertical jump performance by facilitating preloading and reducing energy loss during the eccentric (ECC) phase of the stretch-shortening cycle (SSC). However, the contributions of ECC and isometric (ISO) strength to the countermovement (CMJ) and depth jump (DJ) remain unclear due to variability in assessment methods (e.g., dynamometry, isometric mid-thigh pull) and the limited range of metrics examined in prior research. The aim of this study was to assess correlations between multi-joint lower extremity MES and MIS, obtained using a seated multi-joint isokinetic dynamometer, and 13 vertical ground reaction force (GRF) measures derived from the performance of three maximal effort DJs and CMJs. Twenty-five healthy young adults participated in this study (age = 21.9 ± 2.9 years). Pearson r correlation coefficients were used to assess the statistical significance (α = 0.05) of the relationships between absolute (N) and body mass normalized (BN) maximal strength measures and vertical jumping metrics. Moderate-to-strong positive correlations were identified between MES and MIS with broad performance metrics in CMJ and DJ, including reactive strength index (r = 0.45–0.53, p \u3c 0.05), modified reactive strength index (r = 0.41–0.62, p \u3c 0.05), and jump height (r = 0.59–0.75, p \u3c 0.05). Moderate-to-strong positive correlations were also observed between MES and MIS with CON work (r = 0.58–0.71, p \u3c 0.05) and CON peak power (r = 0.44–0.71, p \u3c 0.05) for both the CMJ and DJ. In contrast, moderate-to-strong negative correlations were observed between MES and MIS with ECC work (r = 0.42–0.62, p \u3c 0.005) and ECC peak power (r = 0.45–0.60, p \u3c 0.05). These findings suggest that enhanced neuromuscular efficiency and joint stiffness in stronger musculature reduce energy absorption during the eccentric phase, minimizing mechanical deformation and preserving elastic energy for concentric propulsion. Combined, MES and MIS optimize force application, energy utilization, and control, which are crucial for maximizing jump height. These findings underscore the role of MES and MIS in influencing jumping performance across both the ECC and CON phases of the SSC. This insight is valuable for practitioners designing training programs aimed at improving vertical jumping ability
16. Use of AI in Teaching Social Statistics or Data Analysis
Get PDFIn face-to-face classrooms, culturally and critically conscious teachers fight to mediate skills, content, and students\u27 backgrounds all within the bounds of a systematically flawed educational institution. For now, Als that aid in writing bypass that kind of meaningful work as Als reflect the corpus of published literature that overwhelmingly reflects historically problematic hierarchical biases
27. Pushing Past the First Draft: Exercises in Revision
Get PDFThis essay provides a series of global and local revision exercises for writing students to use while developing their revision processes. These revision exercises offer physical and digital possibilities, including opportunities to use Al learning models. Each of the included exercises can be done with or without the use of Al to accommodate individual preferences. The provided global revision strategies promote major structural and/or thematic revisions while requiring writing students to take risks. The local revision exercises help writing students tighten up sentences and improve minor stylistic elements while remaining focused on patterns they can begin to identify in future work. These revision exercises focus on revision as an individual activity rather than a social practice; providing guidance on seeking feedback from instructors, peers, or tutors is not within this essay\u27s scope, but writers should practice these exercises in addition to seeking and incorporating such feedback
28. Creating Constitutions With ChatGPT
Get PDFThis chapter explores how students used ChatGPT to construct constitutions in a course on the history of the Age of Revolutions. Student responses, the product, and instructor implications and critiques are included
Forthcoming HWI Monographs
No full textThe HWI Monograph Series is publishing open access monographs on free-ranging domestic cats and coyotes