Many universities have changed their policies regarding the nature of on-campus housing-shifting from gender-specific to coed dorms. This study examines the scope of that transition in the United States. From a sampling of 100 universities in the United States, including the nation's 50 largest universities, it was found that the vast majority of on-campus housing is currently coed in nature. Anecdotal information provided by the housing offices at these universities suggests that this transition is largely driven by student demand and financial considerations. Implications for future research and university policy making are discussed.

There is no recorded maize (Zea mays spp. mays) from sites predating circa cal AD 800 in the northern Lake Michigan or Lake Superior basins of the western Great Lakes, despite the presence of maize microbotanicals including phytoliths and starches in Michigan, New York, and Quebec as early as 400 cal BC. To evaluate the potential for an earlier maize presence in the northern Lake Michigan basin, samples of carbonized food residues adhering to 16 ceramic vessels were obtained from the Winter site (20DE17) located on the Garden Peninsula in the northern Lake Michigan basin. Each sample was split and sent to two analysts. Both analysts identified low incidences of maize starch and phytoliths in multiple samples, with overlapping identifications on several. Three direct accelerator mass spectrometry dates on the carbonized residues reveal maize incorporated into the residues as early as the second century cal BC, 800 years before any regional macrobotanical evidence. Although the method of dispersal cannot be determined, these results support the proposition that initial northern dispersal of maize in the region may have been nearly 800 years earlier than macrobotanical evidence would suggest and is consistent with the timing of its introduction to the lower Great Lakes area.

Exotic species that become invasive can have a strong impact on the success of native species because of traits that enhance their competitive abilities. This study investigates three potential trait differences between common invasive and native shrubs that could enhance the competitive success of invasives: resistance to herbivory, length of autumn leaf retention, and timing of spring leaf emergence. We measured herbivory per plant by leaf-chewing insects, autumn leaf color change and retention, and spring leaf-out in five native and five invasive shrub species in Wildman Woods near Richmond, Indiana, during the fall of 2014 and the spring of 2015. Although we found variation among species, native plants as a group had significantly greater percent leaf herbivory per plant compared to invasive plants, while invasive plants kept chlorophyll significantly later in autumn and had longer leaf retention. Invasive plants also leaf out slightly earlier than native species. Our findings in 2014 were very similar to previous unpublished work in the same area on several of the same species in 2002, 2004, and 2007, suggesting that these patterns are consistent between years. Overall, we found evidence that lower herbivory rates, longer leaf retention in fall, and perhaps earlier leaf-out in spring could improve the competitive abilities of invasive shrub species through increased season-long photosynthesis.

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We characterized yeasts isolated from the integument of North America spruce beetle (Dendroctous rufipennis Kirby) across four populations, using molecular methods to identify 59 representative isolates. Seven yeast species were detected; Wickerhamomyces canadensis (Wickerham) Kurtzman et al. (Sachharomycetales: Saccharomycetaceae) was the most common (74% of isolates) and found in all populations. Isolates of W. canadensis were subsequently tested for in vitro competitive interactions with symbiotic (Leptographium abietinum) and pathogenic (Beauvaria bassiana) fungi, and isolates were nutritionally profiled (N and P content). Three key findings emerged: (1) exposure to yeast headspace emissions had isolate-dependent effects on colony growth of symbiotic and pathogenic fungi; most isolates of W. canadensis slightly inhibited growth rates of symbiotic (L. abietinum) and entomopathogenic (B. bassiana) fungi. (2) A single volatile (2-phenylethanol) was produced by W. canadensis on growth media and was emitted at an average rate of 1.47 µg− 1·mg− 1 yeast·min− 1. Exposure to vapors of synthetic 2-phenylethanol reduced growth rates of both L. abietinum and B. bassiana by 36% on average. (3) W. canadensis cultures were high in both protein (0.8%) and phosphorous (7.2%) in comparison to spruce phloem, but isolates varied in nutritional content with the most nutrient-rich strains isolated from populations in outbreak or post-outbreak population phases. We conclude that W. canadensis is a primary yeast symbiont of D. rufipennis in the southern Rocky Mountains and may serve as a source of volatile emissions that can affect growth of associated microbes. Although W. canadensis has higher nutritional content than spruce tree phloem, the concentration of limiting nutrients (protein and phosphorous) is less than reported for the symbiotic fungus L. abietinum, and variation in nutritional content may be associated with beetle population density.