Significance Climate change during Late Ordovician mass extinction drove an ecologically selective decline in the abundance of deep-water macrozooplankton, accompanied by a shift to simpler, less even communities. These results indicate that the species abundance structure of planktic communities may be a leading indicator of the effects of climate change on biodiversity and a more sensitive gauge of those effects than taxonomic diversity change alone. Additionally, we present a Bayesian likelihood method of habitat inference that may be applicable to other similar cases.

We report the results of a climate change module delivered to 48 Grade 3/4 students in Nova Scotia, Canada. We tested for prior knowledge and evaluated interventional effectiveness using art elicitation. Common climate change misconceptions were demonstrated in their preintervention artwork, while postintervention artwork showed improved concordance with climate change causes and impacts, with little grasp of adaptation or mitigation. Students and teachers alike responded positively to the lessons, and few students demonstrated negative emotional reactions to the material. We highlight some shortcomings, but demonstrate the utility of art elicitation and the appropriateness of introducing climate change to Grade 4 students.

SUMMARY Graptolites of the genus Appendispinograptus feature prominently in Late Ordovician biostratigraphy and studies of biodiversity. Well-documented, but enigmatic, secondary structures extend along the basal spines in mature specimens of three of the four common late Katian species of the genus : A. supernus, A. longispinus , and A. venustus . Using SEM imaging of isolated, three-dimensional specimens of A. supernus , we provide a detailed description of its early growth, as well as confirm that its secondary structures are composed of hollow tubes extending from the sicular and thecal apertures (‘parasiculae’ and ‘parathecae’, respectively). We also describe a collection of Canadian (northern Yukon) appendispinograptids that possess a large heart-shaped, sheet-like basal structure. Detailed comparison (width, thecal length and thecal inclination) with immature specimens from our collection, as well as collections from Russia, China, and Nevada, identifies these specimens as A. leptothecalis , a species not previously known to exhibit any secondary spine modification. The observation of spine modification in A. leptothecalis allows previously unclassified specimens from China, Siberia, and Nevada to be assigned to this species, clarifying our understanding of appendispinograptid biogeography and diversity. However, these structures are difficult to explain functionally. Unlike structures found in other Appendispinograptus species, those in A. leptothecalis decrease usable thecal space, shift drag proximally, and provide no obvious feeding advantage.

Cladistic analysis of some Hirnantian (latest Ordovician) and Rhuddanian-Aeronian (early Silurian) biserial graptolites and basal monograptids has been undertaken in order to test hypotheses of the relationships among the Neograptina ('normalograptids' and their descendents) and to provide a phylogenetic framework for understanding the early Silurian adaptive radiation of graptoloids. It is clear that Silurian graptolite faunas are dominated by two major clades, here named the superfamilies Retiolitoidea and Monograptoidea. Several other lineages whose basal relationships are unresolved, including Normalograptus and Metaclimacograptus, persisted through much of the Llandovery. The Retiolitoidea includes some taxa previously assigned to the Normalograptidae, as well as petalolithids and retiolitids. The Monograptoidea includes akidograptids, dimorphograptids, the uniserial monograptids, as well as stem taxa previously regarded as normalograptids. Both of these major clades had their origins in Late Ordovician time and began their diversification within the Hirnantian-early Rhuddanian, in step with the two main phases of the Hirnantian Mass Extinction. The Neograptina also exhibit an additional interval of accelerated turnover in the Rhuddanian during which the characteristic Silurian fauna largely replaced the Hirnantian Neograptina. One new family, Neodiplograptidae, and four new genera are described: Avitograptus, Rickardsograptus, Korenograptus and Paramplexograptus.

The impact of climate and ocean circulation changes on marine carbon and nitrogen cycling was investigated for a period covering the Late Ordovician Hirnantian glaciation. Three sections were studied: two from Nevada, one proximal and one distal; and one from the Yukon. The opportunity to compare delta C-13(carb), delta C-13(org). and delta C-13(grap) profiles between ocean and epeiric platform settings enabled a more thorough assessment of environmental and diagenetic factors influencing the preservation of seawater delta C-13 values at each stratigraphic section. Using the best preserved sedimentary components from the two Nevada sections, a lowstand sedimentary gradient of similar to 4 parts per thousand was found between platform and ocean settings during the Hirnantian glaciation. Gradients of similar magnitude have been reported from Hirnantian platforms in the Canadian Arctic and Baltic basins. Taking the outboard sections as the most representative of the ocean carbon pool, a mean, positive delta C-13 shift of just 2.7 +/- 0.4 parts per thousand is calculated, which is significantly smaller than the 5-7 parts per thousand positive shifts recorded in epeiric platform settings. The discrepancy is attributed to the effects of local carbon cycling in tropical and subtropical epeiric seas. It is hypothesized that increased carbonate weathering caused delta C-13 values of local carbon weathering fluxes to increase, which in turn caused seawater delta C-13 values to increase in basin proximal settings. In addition, nutrient dust fluxes may have contributed to increased levels of photosynthetic activity in proximal settings, driving sedimentary delta C-13 values even higher-much higher than sediment deposited in outboard settings where carbon exchanges with the surface ocean were less restrictive.A delta N-15 profile reconstructed from deposits of the distal Vinini Creek section records a 1.5 parts per thousand positive shift through the Hirnantian glacial interval. Interpreted as a major Late Ordovician upwelling zone, high organic carbon (>1 wt.%) and high hydrogen indices (400-600) make the Vinini Creek section a suitable candidate for the preservation of original sedimentary delta N-15 records. To explain the results, a conceptual model of ocean nitrogen cycling under greenhouse climate conditions is presented that highlights the role of cyanobacteria as both primary producers and nitrogen fixers. It is hypothesized that in greenhouse climates, the fixed nitrogen inventory of the abyssal ocean was low due to efficient denitrification in the ocean's expansive oxygen minimum zones. This caused algal productivity to become strongly dependenton continuous supplies of fixed nitrogen from cyanobacteria in the photic zone, yielding sedimentary delta N-15 values between 0 and -2 parts per thousand By contrast, the cooler icehouse climate of the Hirnantian led to increased ocean ventilation, greater partitioning of atmospheric oxygen into downwelling surface waters, and oxygen minimum zone shrinkage. As a result, fixed nitrogen levels climbed in the ocean's abyssal depths due to the lower denitrification rates. This in turn allowed nitrogen with high delta N-15 values to recycle back into the photic zone, driving sedimentary delta N-15 values higher during the Hirnantian glaciation. (C) 2009 Elsevier B.V. All rights reserved.

Despite increasing reliance on science and technology in everyday life, public surveys conducted over the past decade have shown consistently low levels of general science literacy, both factual and conceptual, and correspondingly high levels of belief in pseudoscience and the paranormal. Scientists and science educators have largely failed to effectively counter these beliefs through traditional education and outreach initiatives, suggesting a new approach is in order. In the academic setting, general science instruction shows little effect on pseudoscientific belief, but trial projects show that pedagogical approaches that directly engage these beliefs are both popular with students and effective at increasing skepticism. Malgre une dependance accrue de la vie quotidienne sur les sciences et la technologie, les sondages publics realises au cours de la derniere decennie ont constamment reflete un faible niveau de litteracie, tant factuelle que conceptuelle, en sciences generales et un haut niveau correspondant de croyance dans les pseudosciences et le paranormal. Les scientifiques et les educateurs en sciences ont largement echoue dans leurs tentatives de contrer ces croyances par des initiatives de vulgarisation et d’education traditionnelle, ce qui permet de croire qu’une nouvelle approche est de mise. En milieu scolaire ou universitaire, l’apprentissage des sciences generales se revele sans grand effet sur les croyances pseudoscientifiques, mais des projets pilotes demontrent que les approches pedagogiques qui prennent directement a partie ces croyances ont la faveur des ecoliers et etudiants, et parviennent a accroitre le scepticisme.

Despite increasing reliance on science and technology in everyday life, public surveys conducted over the past decade have shown consistently low levels of general science literacy, both factual and conceptual, and correspondingly high levels of belief in pseudoscience and the paranormal. Scientists and science educators have largely failed to effectively counter these beliefs through traditional education and outreach initiatives, suggesting a new approach is in order. In the academic setting, general science instruction shows little effect on pseudoscientific belief, but trial projects show that pedagogical approaches that directly engage these beliefs are both popular with students and effective at increasing skepticism. Malgre une dependance accrue de la vie quotidienne sur les sciences et la technologie, les sondages publics realises au cours de la derniere decennie ont constamment reflete un faible niveau de litteracie, tant factuelle que conceptuelle, en sciences generales et un haut niveau correspondant de croyance dans les pseudosciences et le paranormal. Les scientifiques et les educateurs en sciences ont largement echoue dans leurs tentatives de contrer ces croyances par des initiatives de vulgarisation et d’education traditionnelle, ce qui permet de croire qu’une nouvelle approche est de mise. En milieu scolaire ou universitaire, l’apprentissage des sciences generales se revele sans grand effet sur les croyances pseudoscientifiques, mais des projets pilotes demontrent que les approches pedagogiques qui prennent directement a partie ces croyances ont la faveur des ecoliers et etudiants, et parviennent a accroitre le scepticisme.