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To broaden and emphasize the educational benefits of research to more biology majors in a course setting, we developed and assessed a microbiology-focused course-based undergraduate research experience that utilizes culture-based bacterial enumeration to compare contamination present on different ground beef sources (conventional vs. organic). During the final 3 weeks of the quarter, students learned and practiced common microbiology techniques like dilution math, selective and differential media-based identification, and statistical analysis to evaluate data and test hypotheses. Students were assessed primarily via a formal lab report and a lab practical focused on evaluating process of science and quantitative reasoning skills. The majority of students could write hypotheses and describe variables but were challenged when asked to describe the limitations of the experiments that were conducted as part of this research project. Most students could perform Excel-based graphing and a t test, but many could not solve the complex dilution math required for this project. The greatest barriers to skills mastery represented microbiology-focused concepts, like understanding selective media biases and the nuances of multistep viable counting procedures and outcomes.

The monophyletic Anemone section Anemone (Ranunculaceae) includes predominantly diploid and outbreeding geophytic perennials. A revised taxonomy of the section with 16 species (and some infraspecific taxa) is proposed on the basis of a critical morphological analysis of living populations and extensive herbarium material, together with karyological, cytogenetical and DNA-analytical data. A key, descriptions, figures illustrating some type specimens and differential characters, examples of seedling development and pollen grain micromorphology (scanning electron microscopy) and distribution maps are presented. The position of A. section Anemone within the family is illustrated by a plastid DNA phylogram from sequences of the atpB-rbcL intergenic region. A penalized likelihood approach permitted the approximate dating of the origin and major differentiation phases of the section. The analysis of 20 morphological characters from all species of A. section Anemone with A. blanda (A. section Tuberosa) as an outgroup resulted in a morphology-based phylogram which supports the recognition of four subsections, i.e. Somalienses (one species, northern Somalia), Anemone (three species, Mediterranean area), Biflorae (five species, South-West and Central Asia) and Carolinianae (seven species, North and South America). These data allow a discussion of the phylogenetic diversification and stepwise expansion of the section since the late Miocene (c. 9 Mya). Partly by long distance dispersion, section Anemone has developed from a palaeo-Mediterranean ancestor to its present transcontinental distribution. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 160, 312–354.

The members of Anemone L. sect. Himalayicae (Ulbr.) Juz. (Ranunculaceae) are mainly distributed in the Himalaya of North India, Nepal and Bhutan and the neighbouring mountains of SW China at elevations between 1850 and 4800 m. Their taxonomy is re-evaluated on the basis of a critical morphological analysis of extensive herbarium material. The section is placed in Anemone subgen. Omalocarpus and differentiated into three new series: ser. Obtusilobae, ser. Trullifoliae and ser. Rupestres. A conspectus, keys to species, subspecies and varieties, descriptions of taxa, illustrations and distribution maps are presented. Eleven species with several infraspecific taxa are recognized and their synonymy, variability and relationships are discussed. In addition to the generally accepted species Anemone obtusiloba, A. trullifolia and A. rupestris, we recognize the following: A. polycarpa, A. rockii, A. geum and A. coelestina and four Chinese endemics, A. yulongshanica, A. patula, A. subpinnata and A. subindivisa. Anemone imbricata and A. fuscopurpurea are described but excluded from the section. The origins, morphological differentiations and eco-geographical radiations of Anemone sect. Himalayicae are discussed.

We have developed a ten-week curriculum for molecular biology that uses 16S ribosomal RNA genes to characterize and compare novel bacteria from hot spring communities in Yellowstone National Park. The 16S rRNA approach bypasses selective culture-based methods. Our molecular biology course offered the opportunity for students to learn broadly applicable methods while contributing to a long-term research project. Specifically, students isolated and characterized clones that contained novel 16S rRNA inserts using restriction enzyme, DNA sequencing, and computer-based phylogenetic methods. In both classes, students retrieved novel bacterial 16S rRNA genes, several of which were most similar to Green Nonsulfur bacterial isolates. During class, we evaluated student performance and mastery of skills and concepts using quizzes, formal lab notebooks, and a broad project assignment. For this report, we also assessed student performance alongside data quality and discussed the significance, our goal being to improve both research and teaching methods.

In this study, glass rods suspended at the air-water interface in the runoff channel of Fairy Geyser, Yellowstone National Park, WY, were used as a substratum to promote the development of biofilms that resembled multilayered mat communities in the splash zone at the geyser's source. This approach enabled the establishment of the temporal relationship between the appearance of Cyanobacteria , which ultimately formed the outer green layer, and the development of a red underlayer containing Roseiflexus -like Chloroflexi . This is the first study to define time-dependent successional events involved in the development of differently colored layers within microbial mats associated with many thermal features in Yellowstone National Park. Initial (1-month) biofilms were localized below the air-water interface (60 to 70°C), and the majority of retrieved bacterial sequence types were similar to Synechococcus and Thermus isolates. Biofilms then shifted, becoming established at and above the air-water interface after 3 months. During winter sampling (6 to 8 months), distinct reddish orange microcolonies were observed, consistent with the appearance of Roseiflexus -like sequences and bacteriochlorophyll a pigment signatures. Additionally, populations of Cyanobacteria diversified to include both unicellular and filamentous cell and sequence types. Distinct green and red layers were observed at 13 months. Planctomycetes -like sequences were also retrieved in high abundance from final biofilm layers and winter samples. Finally, biomass associated with geyser vent water contained Roseiflexus -like sequence types, in addition to other high-abundance sequence types retrieved from biofilm samples, supporting the idea that geothermal water serves as an inoculum for these habitats.

We characterized and compared five geographically isolated hot springs with distinct red-layer communities in Yellowstone National Park. Individual red-layer communities were observed to thrive in temperatures ranging from 35 to 60°C and at pH 7 to 9. All communities were dominated by red filamentous bacteria and contained bacteriochlorophyll a (Bchl a ), suggesting that they represented novel green nonsulfur (GNS) bacteria. The in vivo absorption spectra of individual sites were different, with two sites showing unusual Bchl a protein absorption bands beyond 900 nm. We prepared and analyzed 16S rRNA libraries from all of these sites by using a combination of general bacterial primers and new GNS-specific primers described here. These studies confirmed the presence of novel GNS-like bacteria in all five communities. All GNS-like clones were most similar to Roseiflexus castenholzii , a red filamentous bacterium from Japan that also contains only Bchl a . Phylogenies constructed by using GNS-like clones from Yellowstone red-layer communities suggest the presence of a moderately diverse new “red” cluster within the GNS lineage. Within this cluster, at least two well-supported subclusters emerged: YRL-A was most similar to Roseiflexus and YRL-B appeared to be novel, containing no known isolates. While these patterns showed some site specificity, they did not correlate with observed Bchl a spectrum differences or obvious features of the habitat.

With few exceptions, the narcissus anemone has been known as Anemone narcissiflora since its original orthography ("uarcissifolia") was corrected by Linnaeus (Syst. Nat., ed. 10: 1084. 1759, as "narcissifl. "). Linnaeus's rationale for the correction seems clear. The initial "u" is an upside-down "n" and a strict printer's error. The termination "-flora" also is logical because among the synonyms listed in the protologue was "Ranunculus montanus hirsutus humilior, narcissi flore. Bauh. pin. 182". Furthermore, the plant has compound basal leaves and trifid to pinnatifid involucral leaves, both distinctly different from the entire, linear leaves of Narcissus. Finally, its flowers are somewhat reminiscent of daffodil flowers as implied by Bauhin (Pinax: 182. 1623). Most workers have accepted Linnaeus's correction of "uarcissifolia" to "narcissiflora". So established was this orthographic correction among Linnaean scholars that Steam (Sp. PI. Facs., App.: 108. 1959) indexed the name as "narcissiflora, ut uarcissifolia" without comment (see also Richter, Codex Bot. Linn.: 539. 1835). Perhaps the best indication of Linnaeus's own view of the orthography comes from his herbarium where the lectotype (No. 710.31, LINN!) is