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Summary: Sequencing herbarium specimens can be instrumental in answering ecological, evolutionary, and taxonomic inquiries. We developed a protocol for sequencing herbarium specimens of rust fungi (Pucciniales) and proceeded to sequence specimens ranging from 4 to 211 yr old from five different genera.We then obtained sequences from an economically important biological control agent, Puccinia suaveolens, to highlight the potential of sequencing herbarium specimens in an ecological sense and to evaluate the following hypotheses: (1) The population structure of a plant pathogen changes over time, and (2) introduced pathogens are more diverse in their native range.Our efforts resulted in sequences from 87 herbarium specimens that revealed a high level of diversity with a population structure that exhibited spatial–temporal patterns. The specimens sequenced from Europe showed more diversity than the ones from North America, uncovering an invasion pattern likely related to its European native host in North America. Additionally, to the best of our knowledge, the specimen from France collected in c. 1811 is the oldest herbarium specimen sequenced from kingdom Fungi.In conclusion, sequencing old herbarium specimens is an important tool that can be extrapolated to better understand plant–microbe evolution and to evaluate old type specimens to solidify the taxonomy of plant pathogenic fungi. [ABSTRACT FROM AUTHOR]

Walleye Sander vitreus and Yellow Perch Perca flavescens are culturally, economically, and ecologically significant fish species in North America that are affected by drivers of global change. Here, we review and synthesize the published literature documenting the effects of ecosystem changes on Walleye and Yellow Perch. We focus on four drivers: climate (including temperature and precipitation), aquatic invasive species, land use and nutrient loading, and water clarity. We identified 1,232 tests from 370 papers, split evenly between Walleye (n = 613) and Yellow Perch (n = 619). Climate was the most frequently studied driver (n = 572), and growth or condition was the most frequently studied response (n = 297). The most commonly reported relationship was "no effect" (42% of analyses), usually because multiple variables were tested and only a few were found to be significant. Overall responses varied among studies for most species‐response–driver combinations. For example, the influence of invasive species on growth of both Walleye and Yellow Perch was approximately equally likely to be positive, negative, or have no effect. Even when results were variable, important patterns emerged; for example, growth responses of both species to temperature were variable, but very few negative responses were observed. A few relationships were relatively consistent across studies. Invasive species were negatively associated with Walleye recruitment and abundance, and higher water clarity was negatively associated with Walleye abundance, biomass, and production. Some variability in responses may be due to differences in methodology or the range of variables studied; others represent true context dependence, where the effect of a driver depends on the influence of other variables. Using common metrics of impact, publishing negative results, and robust analytical approaches could facilitate comparisons among systems and provide a more comprehensive understanding of the responses of Walleye and Yellow Perch to ecosystem change. [ABSTRACT FROM AUTHOR]

Objectives: Neisseria meningitidis is a leading cause of meningitis and septicaemia. The hyperinvasive ST-11 clonal complex (cc11) caused serogroup C (MenC) outbreaks in the US military in the 1960s and UK universities in the 1990s, a global Hajj-associated serogroup W (MenW) outbreak in 2000-2001, and subsequent MenW epidemics in sub-Saharan Africa. More recently, endemic MenW disease has expanded in South Africa, South America and the UK, and MenC cases have been reported among European and North American men who have sex with men (MSM). Routine typing schemes poorly resolve cc11 so we established the population structure at genomic resolution.Methods: Representatives of these episodes and other geo-temporally diverse cc11 meningococci (n = 750) were compared across 1546 core genes and visualised on phylogenetic networks.Results: MenW isolates were confined to a distal portion of one of two main lineages with MenB and MenC isolates interspersed elsewhere. An expanding South American/UK MenW strain was distinct from the 'Hajj outbreak' strain and a closely related endemic South African strain. Recent MenC isolates from MSM in France and the UK were closely related but distinct.Conclusions: High resolution 'genomic' multilocus sequence typing is necessary to resolve and monitor the spread of diverse cc11 lineages globally. [ABSTRACT FROM AUTHOR]

• Thirty exotic plant species, representing 11 families were observed. • Exotic species were observed at both northern temperate and boreal forest sites. • Exotic species richness increased with native species richness. • Maximum exotic species richness was observed with intermediate disturbance. • Exotic species had traits typical of ruderal species. Although exotic (i.e., non-native) plant species are among the main factors contributing to ecosystem change globally, investigations of northern temperate and boreal forest ecosystems in North America in the context of invasion science are scarce. Multiple hypotheses, including the 'biotic resistance', 'intermediate disturbance' and 'disturbance-mediated' hypotheses, can serve as a framework to assess invasibility. Here we used the NEBIE (natural disturbances and extensive, basic, intensive, and elite silviculture intensities) plot network, consisting of field sites across different forest types that originated from a range of silviculture systems to assess the role of silviculture intensity on exotic plant diversity. Botanical surveys were conducted pre- and two-, five-, and ten years post-forest harvesting. Thirty exotic plant species were observed across all studied forests, of which 20 belonged to the Asteraceae, Fabaceae, and Poaceae families. Exotic species richness was highly correlated with native species richness and peaked as a result of intermediate linked-press (i.e., climate, soils, historic disturbance regimes, and silviculture systems) stresses/disturbances and compounded pulse (i.e., harvest intensity, site preparation, and herbicide use) disturbances for all post-harvesting measurement years. Observed exotic species are considered to have traits consistent with those of ruderal species. In this context, our results support the intermediate disturbance and disturbance-mediated hypotheses, but not the biotic resistance hypothesis. To reduce the richness of exotic plant species in northern temperate and boreal forests we recommend minimizing the use of intermediate compounded pulse disturbances. [ABSTRACT FROM AUTHOR]

Throughout North America, and beyond, there are significant challenges facing educational institutions, including the need for leadership. The wave of retirements facing postsecondary institutions, during turbulent and unpredictable times, has the potential to leave significant leadership gaps within these important organizations. Drawing on a predominantly qualitative methodology, this study suggests that leadership development activities do, in fact, influence leaders. Leadership development activities are formal (e.g., pursuit of a Master of Education), nonformal (e.g., workshops), and informal (e.g., on-the-job experience). These activities contribute to the development of personal, interpersonal, and organizational capacity. Barriers are experienced by educational leaders throughout their journeys and these barriers are often found to include work-life balance issues, inadequate institutional resourcing, and at times, organizational politicking. Despite these barriers, leadership development is recognized to be a valuable pursuit for educational leaders. The conclusion provides implications for future research in this area as well as insights for practitioners interested in leadership development in postsecondary educational institutions. [ABSTRACT FROM AUTHOR]