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Incorporating counterstereotypical scientist role models into undergraduate biology courses is a powerful, evidence-based way to support student persistence in STEM fields. However, educational resources featuring counterstereotypical scientists could unintentionally have adverse impacts on student attitudes towards science. Here, we leveraged a multi-institution experiment that manipulated whether educational materials included information on the obstacles faced by counterstereotypical scientists in their careers. After students received these variable materials, we documented the obstacles they perceived they may face as scientists. Through the lens of attribution theory, we found that students are aware of a variety of obstacles they would face as scientists and that student perceptions of those obstacles are not changed by sharing the obstacles that scientists had to overcome. We encourage instructors to share scientists’ stories of the obstacles they faced in their careers without concern that this will alter students’ perceptions of careers in science. 

Abstract Mite domatia — small structures on plant leaves that house mutualistic mites — are widespread across plants yet remain relatively understudied. Here we investigate the chemistry and micromorphology of mite domatia across sympatric species of broadleaf deciduous woody species that have convergently evolved tuft-form mite domatia. Specifically, we test whether domatia display similar micromorphological and chemical properties using metabolomics and scanning electron microscopy across multiple independent sympatric lineages. To identify domatia-specific phenotypes, we also compare tissue within domatia to that of nearby leaf tissue on each of the four domatium-bearing species, and test whether species with domatia exhibit reduced chemical defense relative to species that lack domatia using four additional species that lack prominent domatia as a control. We found that domatium-bearing species had significantly lower total phenolic concentrations and lower total defense compound abundance compared to control species, consistent with an evolutionary trade-off between chemical and mutualistic defense. However, within leaves, domatium tissue chemical defense did not differ from surrounding laminar tissue. In contrast, trichome morphology showed clear convergent modification: domatium trichomes were 24–31% longer than trichomes elsewhere on the leaf, a pattern reversed in control species. Together, our findings shed light on the degree of phenotypic convergence in a widespread, ecologically important trait. 

Abstract While educators strive to foster inclusive learning environments, a commonly reported concern is the prospect of student resistance to inclusive course content. To investigate the extent of student resistance to inclusive activities, we conducted a post-hoc analysis of more than 6000 student responses to survey questionnaires from a nationwide study that evaluated data literacy activities implemented in undergraduate biology courses that featured scientist role models with counter-stereotypical identities. We found few instances of active student resistance to these inclusive activities. Most student responses (94%) displayed no clear resistance to the activities. Of the resistant responses, only 16 (0.25%) were clearly resistant to the inclusive content within the data literacy activities. This study is the first to attempt to quantify student resistance to inclusive activities featuring counter-stereotypical scientist role models and serves as a springboard for future exploration of student resistance. 

The processes driving defense trait correlations may vary within and between species based on ecological or environmental contexts. However, most studies of plant defense theory fail to address this potential for shifts in trait correlations across scales. In this work, we tested for correlations between multiple defensive traits (secondary chemistry, carbon to nitrogen ratio, domatia, leaf toughness, trichomes, and pearl bodies) across a common garden of 21Vitisspecies and eighteen genotypes of the speciesVitis ripariato identify when and where patterns of defense trait evolution persist or break down across biological scales. Additionally, we asked whetherVitisdefense trait investment correlates with environmental variables as predicted by plant defense theory, using environmental metrics for eachVitisspecies andV. ripariagenotype from the GBIF and WorldClim databases. We tested for correlations between defense trait investment, herbivore palatability, and environmental variables using phylogenetically informed models. Beyond a few likely physiological exceptions, we observed a lack of significant correlations between defense traits at both intra‐ and interspecific scales, indicating that these traits evolve independently of each other inVitisrather than forming predictable defense syndromes. We did find that investment in carbon:nitrogen (at both scales) and pearl bodies increases with proximity to the equator, demonstrating support for plant defense theory's prediction of higher investment in defenses at more equatorial environments for some, but not all, defense traits. Overall, our results challenge commonly held hypotheses about plant defense evolution, namely the concept of syndromes, by demonstrating that strong correlations between defense traits are not the prevailing pattern both across and withinVitisspecies. Our work also provides the first comprehensive evaluation of the evolutionary divergence in approaches thatVitis, a genus with significant agricultural value, have evolved to defend themselves against herbivores. 

Mutualisms are mediated by adaptive traits of interacting organisms and play a central role in the ecology and evolution of species. Thousands of plant species possess tiny structures called “domatia” that house mites which protect plants from pests, yet these traits remain woefully understudied. Here, we release a worldwide database of species with mite domatia and provide an evaluation of the phylogenetic and geographic distribution of this mutualistic trait. With >2,500 additions based on digital herbarium scans and published reports, we increased the number of known species with domatia by 27% and, importantly, documented their absence in >4,000 species. We show that mite domatia likely evolved hundreds of times among flowering plants, occurring in an estimated ~10% of woody species representing over a quarter of all angiosperm families. Contrary to classic hypotheses about the evolutionary drivers of mutualism, we find that mite domatia evolved more frequently in temperate regions and in deciduous lineages; this pattern is concordant with a large-scale geographic transition from predominantly ant-based plant defense mutualisms in the tropics to mite-based defense mutualisms in temperate climates. Our data also reveal a pattern of evolutionary convergence in domatia morphology, with tuft-form domatia more likely to evolve in dry temperate habitats and pit domatia more likely to evolve in wet tropical environments. We have shown climate-associated drivers of mite domatia evolution, demonstrating their utility and power as an evolutionarily replicated system for the study of plant defense mutualisms. 

Despite broad consensus that highlighting counter-stereotypical scientist role models in educational materials promotes equity and success, the specific elements that make these materials effective remain untested. Are pictures of counter-stereotypical scientists enough to communicate to students that scientists come from a variety of backgrounds, or is additional information required? To parse the effects of including visual depictions and humanizing information about scientists featured in biology course materials, we distributed three randomized versions of assignments over several academic terms across 36 undergraduate institutions (n> 3700 students). We found that including humanizing information about scientists was key to increasing student engagement with the biology course materials. The positive effect of humanizing information was especially important for students who related to the scientists. Structural equation modelling revealed the extent to which students related to scientists mediated the positive effect of humanizing descriptions on student engagement. Furthermore, our results were strongest among students who shared one or more excluded identity(s) with the featured scientists. Our findings underscore the importance of providing students with examples of humanized and relatable scientists in classrooms, rather than simply adding a photo to increase representation. 

Featuring a diversity of scientists within curriculum provides opportunities for students to relate to them. We manipulated the amount and type of information students received about scientists. We found including personal, humanizing information increased the extent to which students related to them, with implications for curriculum development. 

ABSTRACT Many plants engage in indirect defense via tri‐trophic interactions whereby plants provide resources such as food or shelter to mutualists in exchange for protection against herbivores and pathogens, increasing plant fitness. As temperature regimes shift under climate change, understanding the influence of temperature on tri‐trophic defensive interactions is increasingly important. However, where plant species host multiple tri‐trophic defensive interactions, we still lack an understanding of if each interaction, even within the same system, responds in the same way to temperature. In this study, we monitored black cherry (Prunus serotina)seedlings for 10 weeks under ambient and increased temperatures to explore the effects of temperature on two different tri‐trophic defensive interactions between black cherry and: (1) mutualistic leaf domatia‐dwelling mites and leaf fungi; and (2) arthropod predators and herbivores. We found that the positive association between mite abundance and domatia size increased by 8.7% on warmed plants, while warming weakened the positive relationship between mite abundance and the abundance of foliar fungi by 14%, though warmer conditions alone did not affect the abundances of any of these groups. Further, warming increased the abundance of arthropod predators by 116% and decreased the amount of herbivory plants experienced by 42%, but did not modify the impact predators had on herbivory. Ultimately, the differences among interacting species with warming did not translate to differences in plant growth, indicating black cherry can be robust to at least some of the variation in species interactions caused by changing temperatures in the short term. These findings illustrate that warming can modify the abundance of, and relationships between, some but not all tri‐trophic defensive interactions in a given system, further confirming that temperature does not impact plant interactions uniformly. 

ABSTRACT Mite–plant defense mutualisms are among the most common defense mutualisms in the world—yet studies providing basic information on their prevalence in plant communities remain rare. Here, we systematically surveyed common woody plants in a North American deciduous forest for the presence of plant–mite mutualistic interactions. We scored 16 common woody species in a wooded natural area for the presence and number of mite domatia—small structures on the underside of plant leaves that are known to house mutualistic mites. We found that 80% of common woody species in the forest had mite domatia, the highest reported percentage of mite domatia in any survey conducted thus far. We paired our survey with a quantification of the number of mites found on each leaf and investigated the relationship between mite domatia and mite abundance within and across species. We found that plants with mite domatia had significantly more mites on their leaves than species that lacked mite domatia, and that plants with more domatia had more mites. Together, our study provides much needed systematic survey data on plant–mite mutualism prevalence in an important plant community and points to northern temperate forests as a promising system to study plant–mite mutualisms in high densities in the future.