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Over the last decade, reform in science education has placed an emphasis on the science practices as a way to engage students in the process of science and improve scientific literacy. A critical component of developing scientific literacy is learning to apply quantitative reasoning to authentic scientific phenomena and problems. Students need practice moving fluidly (or fluently) between math and science to develop a habit of mind that encourages the application of quantitative reasoning to real-world scenarios. Here we present a student-facing model that challenges students to think across these two fields. The model brings together math and science with a goal to increase scientific literacy by engaging students in quantitative reasoning within the context of scientific questions and phenomena. In the classroom, the model serves to help students visualize the logical and necessary moves they make as they use quantitative reasoning to connect science practices with mathematical thinking. 

Summary The anthropogenic spread of disease from captive to wild amphibian populations (referred to as spillover) is linked to global amphibian declines. Disinfecting procedures and protocols exist to mitigate pathogen transmission to and within natural areas, but understanding of visitor attitudes and behaviour regarding their adoption is limited. We surveyed visitors in two natural areas in a global amphibian biodiversity hotspot to assess their attitudes regarding pathogen spread in such areas and analysed the factors influencing their behavioural intentions to take specific actions to prevent pathogen spillover. Visitors’ willingness to take action was influenced by their attitudes, behavioural control and trust in wildlife/land managers, whereas socio-demographic characteristics were less influential. These findings help us to understand visitor behaviour with respect to amphibian biosecurity in natural areas and inform enhanced biosecurity measures and strategic messaging to reduce pathogen spillover. 

Characterizing the population density of species is a central interest in ecology. Eastern North America is the global hotspot for biodiversity of plethodontid salamanders, an inconspicuous component of terrestrial vertebrate communities, and among the most widespread is the eastern red-backed salamander,Plethodon cinereus. Previous work suggests population densities are high with significant geographic variation, but comparisons among locations are challenged by lack of standardization of methods and failure to accommodate imperfect detection. We present results from a large-scale research network that accounts for detection uncertainty using systematic survey protocols and robust statistical models. We analysed mark–recapture data from 18 study areas across much of the species range. Estimated salamander densities ranged from 1950 to 34 300 salamanders ha⁻¹, with a median of 9965 salamanders ha⁻¹. We compared these results to previous estimates forP. cinereusand other abundant terrestrial vertebrates. We demonstrate that overall the biomass ofP. cinereus, a secondary consumer, is of similar or greater magnitude to widespread primary consumers such as white-tailed deer (Odocoileus virginianus) andPeromyscusmice, and two to three orders of magnitude greater than common secondary consumer species. Our results add empirical evidence thatP. cinereus, and amphibians in general, are an outsized component of terrestrial vertebrate communities in temperate ecosystems. 

Western palearctic salamander susceptibility to the skin disease caused by the amphibian chytrid fungusBatrachochytrium salamandrivorans(Bsal) was recognized in 2014, eliciting concerns for a potential novel wave of amphibian declines following theB. dendrobatidis(Bd) chytridiomycosis global pandemic. Although Bsal had not been detected in North America, initial experimental trials supported the heightened susceptibility of caudate amphibians to Bsal chytridiomycosis, recognizing the critical threat this pathogen poses to the North American salamander biodiversity hotspot. Here, we take stock of 10 years of research, collaboration, engagement, and outreach by the North American Bsal Task Force. We summarize main knowledge and conservation actions to both forestall and respond to Bsal invasion into North America. We address the questions: what have we learned; what are current challenges; and are we ready for a more effective reaction to Bsal’s eventual detection? We expect that the many contributions to preemptive planning accrued over the past decade will pay dividends in amphibian conservation effectiveness and can inform future responses to other novel wildlife diseases and extreme threats. 

Abstract Antifungal resistance in pathogenic fungi is a growing global health concern. Nonpathogenic laboratory strains of Saccharomyces cerevisiae are an important model for studying mechanisms of antifungal resistance that are relevant to understanding the same processes in pathogenic fungi. We have developed a series of laboratory modules in which high school students used experimental evolution to study antifungal resistance by isolating azole-resistant S. cerevisiae mutants and examining the genetic basis of resistance. We have sequenced 99 clones from these experiments and found that all possessed mutations previously shown to impact azole resistance, validating our approach. We additionally found recurrent mutations in an mRNA degradation pathway and an uncharacterized mitochondrial protein (Csf1) that have possible mechanistic connections to azole resistance. The scale of replication in this initiative allowed us to identify candidate epistatic interactions, as evidenced by pairs of mutations that occur in the same clone more frequently than expected by chance (positive epistasis) or less frequently (negative epistasis). We validated one of these pairs, a negative epistatic interaction between gain-of-function mutations in the multidrug resistance transcription factors Pdr1 and Pdr3. This high school–university collaboration can serve as a model for involving members of the broader public in the scientific process to make meaningful discoveries in biomedical research. 

Abstract The resources for carrying out and analyzing microbial evolution experiments have become more accessible, making it possible to expand these studies beyond the research laboratory and into the classroom. We developed five connected, standards‐aligned yeast evolution laboratory modules, called “yEvo,” for high school students. The modules enable students to take agency in answering open‐ended research questions. In Module 1, students evolve baker's yeast to tolerate an antifungal drug, and in subsequent modules, investigate how evolved yeasts adapted to this stressful condition at both the phenotype and genotype levels. We used pre‐ and post‐surveys from 72 students at two different schools and post‐interviews with students and teachers to assess our program goals and guide module improvement over 3 years. We measured changes in student conceptions, confidence in scientific practices, and interest in STEM careers. Students who participated in yEvo showed improvements in understanding of activity‐specific concepts and reported increased confidence in designing a valid biology experiment. Student experimental data replicated literature findings and has led to new insights into antifungal resistance. The modules and provided materials, alongside “proof of concept” evaluation metrics, will serve as a model for other university researchers and K − 16 classrooms interested in engaging in open‐ended research questions using yeast as a model system. 

Abstract The recent decline in wild populations of amphibians worldwide coincides with the period of rapid growth in the global trade of wildlife. The potential for pathogen transmission within and beyond the pet amphibian trade network makes it important to explore the attitudes and behavior of businesses involved in the industry. We surveyed US businesses involved in the pet amphibian trade industry to characterize their attitudes and behaviors and identify business characteristics that could influence percieved risk of pathogen transmission in trade. We found that amphibian businesses acquire their animals from a variety of sources (e.g., importers, wholesalers, retailers, breeders, hobbyists, wild), are aware of the threat of emerging pathogens, and are concerned about the potential spillover of pathogens from captive to wild populations. Attitudes and behaviors of businesses toward pathogens varied among business types (e.g., size of business, the share of amphibian sales, mode of business operation). Moreover, businesses expressed a strong interest in acquiring amphibians that are free of pathogens and indicated a willingness to pay a price premium to acquire certified disease‐free animals. Our results indicate that the US pet amphibian trade industry is willing to participate in healthy (clean) trade practices and increasing product prices may be one option to compensate for expenses. A government program to support pathogen‐free certification would likely facilitate implementation.