Search

The Joggins Fossil Cliffs UNESCO World Heritage Site is managed by the Joggins Fossil Institute (JFI), a charitable organization consisting of a volunteer board of directors and a small staff team. This article illustrates how the governance of this small institution evolved since its inception nearly 20 years ago. Originally, the institute had a traditional hierarchical management structure. But 10 years later, when it had matured and positions and responsibilities no longer needed to be invented, it adopted a flat management structure, which continues to function in a manner that does justice to the demands of running this small centre. We document our unique case study here because we believe it may help other (potential) geoheritage sites, UNESCO sites or others, in crafting a governance structure. [ABSTRACT FROM AUTHOR]

The discovery of a new megasecopteron,Brodia jogginsensissp. nov., is reported from the Joggins Formation, a UNESCO World Heritage Site in Nova Scotia, Canada. The new species diagnosis is based on the unique pattern of hind wing venation bearing three anterior branches of MP and pectinate CuP with four posterior branches. Its occurrence in Langsettian deposits of the Maritimes Basin correspond well with other Pennsylvanian Brodiidae known from the Coal Measures of the UK and Mazon Creek in Illinois, USA. Based on our re-examination, we propose to transfer the genusPyebrodia, withP. martinsnetoiBrauckmann & Herd, 2003, described as a putative member of Brodiidae, into Palaeodictyoptera familyincertae sedisas it lacks most of the diagnostic features of Brodiidae. The holotype ofEubrodia dabasinskasiCarpenter, 1967, housed in a private collection, was supplemented by the description of an additional specimen housed in The Field Museum, Chicago. The fossil record of Brodiidae is reviewed and additional remarks concerning the wing morphology and the function of specialized structures, such as reinforcements in the form of a specialized crossvein between A1 and CuP, are given. Putative nymphs of Brodiidae and development of wings in Megasecoptera are discussed. http://zoobank.org/urn:lsid:zoobank.org:pub:741846CB-FAD0-4103-90D3-2896D8909E94 [ABSTRACT FROM PUBLISHER]

One hundredSelenichnites rossendalensis(excavations), sometimes with associated trackways, have been found at Joggins Fossil Cliffs (Nova Scotia, Canada; Pennsylvanian). The majority of theSelenichnitesfound in this study contain only one lunate cast and some are distinguished by linear ridges that project behind a single lunate cast. A detailed investigation of the morphology and orientation of theseSelenichnites—attributable to xiphosurans, relatives of modern horseshoe crabs (Limulus polyphemus)—yields an understanding of xiphosuran digging behavior. Statistical analysis of 96 lunate casts from two populations ofSelenichnitesseparated by several hundred thousand years shows, with 99% confidence, that the prosomas (heads) of the younger population are smaller. Further study of the wealth ofSelenichnitesat Joggins will be useful to determine which factors control xiphosuran body-size changes and the timescale on which those changes can be seen manifest in a population. The smallest knownSelenichnites(7 mm wide) is also reported. [ABSTRACT FROM PUBLISHER]

A review of all available specimens of fossil fishes from the classic Pennsylvanian Joggins locality of Nova Scotia, Canada, reveals the existence of a diverse community of chondrichthyans (xenacanthids, ctenacanthids and the enigmatic Ageleodus), acanthodians (gyracanthids), sarcopterygians (rhizodontids, megalichthyids, rhizodopsids and dipnoans) and actinopterygians (haplolepids). Reassessment of supposed endemic species ( Ctenoptychius cristatus, Sagenodus plicatus, Gyracanthus duplicatus) indicates they are invalid, and overall, the assemblage comprises cosmopolitan taxa that were widespread around the coasts of tropical Pangaea. Strontium isotope analysis of fish remains and a critical study of their facies context suggest that these fish communities occupied bodies of water with salinities across the marine-freshwater spectrum. This preponderance of euryhaline forms implies a community structure quite distinct from that of today and might represent a transitory phase prior to the establishment of fully freshwater fish communities. Interpretation of fish ecology provides further evidence that the Joggins Formation was deposited in a paralic setting, and the recognition of one previously undetected brackish incursion strengthens the link between sedimentary cycles at Joggins and Milankovitch-induced glacio-eustatic change. Furthermore, interregional correlation of these marine transgressions supports palynostratigraphical arguments for an early Langsettian age for the Joggins Formation. This places tighter constraints on the age of the earliest known crown amniote, Hylonomus lyelli, an important calibration point used in phylogenomic studies. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Triassic-Jurassic extinction resulted in the near demise of the ammonoids. Based on a survey of ammonoid expansion rates, coiling geometry and whorl shape, we use the Raup accretionary growth model to outline a universal morphospace for planispiral shell geometry. We explore the occupation of that planispiral morphospace in terms of both breadth and density of occupation in addition to separately reviewing the occurrence of heteromorphs. Four intervals are recognized: pre-extinction (Carnian to Rhaetian); aftermath (Hettangian); post-extinction (Sinemurian to Aalenian) and recovery (Bajocian to Callovian). The pre-extinction and recovery intervals show maximum disparity. The aftermath is marked by the disappearance of heteromorphs and a dramatic reduction in the range of planispiral morphologies to a core area of the morphospace. It is also characterized by an expansion into an evolute, slowly expanding part of the morphospace that was not occupied prior to the extinction and is soon abandoned during the post-extinction interval. Aftermath and post-extinction ammonoid data show a persistent negative correlation whereby rapid expansion rates are associated with narrow umbilical widths and often compressed whorls. The permanently occupied core area of planispiral morphospace represents generalist demersals whose shells were probably optimizing both hydrodynamic efficiency and shell stability. All other parts of the planispiral morphospace, and the pelagic modes of life the shells probably exploited, were gradually reoccupied during the post-extinction interval. Planispiral adaptation was by diffusion away from the morphospace core rather than by radical jumps. Recovery of disparity was not achieved until some 30 Myr after the extinction event. [ABSTRACT FROM AUTHOR]

Grey, M., Finkel, Z.V., Pufahl, P.K. & Reid, L.M. 2012: Evolutionary mode of the ostracod, Velatomorpha altilis, at the Joggins Fossil Cliffs UNESCO World Heritage Site. Lethaia, Vol. 45, pp. 615-623. The estuarine ostracod Velatomorpha altilis was analysed for size and shape changes over a 2-3 million-year interval within a portion of the Joggins Fossil Cliffs World Heritage Site. This represents one of a very few number of studies focused on evolutionary trends within marginal environments and contributes to a growing body of research that attempts to link evolutionary patterns with processes. We measured nearly 400 ostracod specimens and used a quantitative model-based test to assess mode of evolution. Samples of ostracods were also analysed for their stable oxygen and carbon isotopic compositions in an attempt to supplement paleoenvironmental interpretations. Stasis was the strongly supported model for mode of evolution in both size and shape metrics, lending support to previous hypotheses that organisms from fluctuating, and therefore stressed, environments, should exhibit stasis because they are genetically well adapted to environmental change over geological time-scales. Stable isotopic compositions indicate samples were diagenetically altered and thus do not preserve a primary signature of paleoenvironmental conditions. Future work should look to other marginal organisms to test whether stasis is indeed a trend in these types of environments. □ Carboniferous, estuarine ostracod, environment, evolutionary mode. [ABSTRACT FROM AUTHOR]

We studied morphological variation of the bivalve Buchia over its geographical and temporal range. Buchia was widely distributed during the Late Jurassic and Early Cretaceous, and, while previous quantitative studies have shown that species are characterized by large amounts of variation, there have been no prior attempts to measure how morphology varies geographically. We employed traditional morphometric techniques using nine linear/angular measurements on 1855 buchiid shells from eight localities taken from widely separated, but mostly coeval, sections across its range. Principal component and canonical variate analyses indicate that geographical morphospace of buchiids varied significantly, but we did not find evidence of a latitudinal gradient in shell shape. The amount of variation between localities was similar to the amount of variation between species, indicating the importance of geographical effects on morphology. Disparity (morphological diversity within a taxon, calculated by the sum of variances) and diversity (number of species) were calculated for each location and time period (age). Disparity and diversity reached ultimate lows just before the genus' extinction in the Hauterivian, and is suggestive that extinction was morphologically selective. We did not find significant trends for either metric, but there were discordances throughout its temporal range. Latitudinal trends of disparity and diversity within Buchia are not apparent. This research adds to the growing body of work on geographical variation and is a preliminary step to understanding the nature and variation of buchiid species and of biodiversity in general. [ABSTRACT FROM AUTHOR]

Joggins is a famous fossil locality in Nova Scotia, Canada. Hewn by some of the world's highest tides on the Bay of Fundy, these crumbling cliffs shed light on the life and environments of the Carboniferous Coal Age, 315 million years ago. The site has been a magnet for geologists since the early nineteenth century. Charles Lyell described it as the world's best coal-bearing section and together with his colleague, William Dawson, reported amazing fossil forests and a rich terrestrial fauna. Since that golden age, the rate of new fossil discoveries has hardly diminished and in recognition of its importance, the Joggins Fossil Cliffs was awarded UNESCO World Heritage Status in 2008. Even after many years of study, it remains a tremendous thrill for us to explore this ‘classic locality’ in far-flung Nova Scotia. Each winter storm, rock fall, and tide brings with it the tantalizing possibility of new fossils and new scientific insights. In this article we share something of our excitement for Joggins and provide an up to date field guide for those wishing to unlock its secrets. [ABSTRACT FROM AUTHOR]

This study examined adolescent peer-on-peer sexual assault victimization occurring within and outside school. The sample consisted of 1,086 7th through 12th grade students, with a mean age of 15. Most of the respondents were White (54%) or Black (45%), and approximately half of respondents were female (54%). A modified version of the Sexual Experiences Survey was used to assess opposite sex sexual victimization in 7th through 12th grade students. Rates of peer sexual assault were high, ranging from 26% of high school boys to 51% of high school girls. School was the most common location of peer sexual victimization. Characteristics of assault varied by location, including type of victimization, victims’ grade level, relationship to the perpetrator, type of coercion, and how upsetting the assault was. Distinctions between sexual assault occurring in and out of school are conceptualized with literature on developmental changes in heterosexual relationships and aggression. [ABSTRACT FROM AUTHOR]

Buchiid bivalves are geographically widespread in Upper Jurassic and Lower Cretaceous strata of the Northern Hemisphere. They are often abundant and their short stratigraphic ranges make them ideal biostratigraphic index fossils; these characteristics also render them useful for study of evolutionary patterns. We used multivariate methods to determine if we could discriminate between species of Buchia and examine how morphological characters change through time within the genus. Using ten morphological characters to describe shell shape and size, we tested for taxonomic differences and morphologic change in populations of buchiids collected from a single stratigraphic section on Grassy Island, located along the west coast of Vancouver Island, British Columbia. Morphometric analysis utilized traditional morphological metrics and techniques, including linear and angular measurements as well as Fourier (outline shape) analyses. Phenetic discrimination revealed considerable overlap among the recognized species in the morphospace, as well as a fairly low discriminatory power between species when compared as a group using a step-wise canonical variate analysis. Step-wise discriminant analyses between species pairs gave rise to much higher classification rates, suggesting that different characters are important for distinguishing between different species pairs. Our results also indicate that single individuals and small sample sizes of Buchia specimens are insufficient for biostratigraphic discrimination (unless other rarely preserved features such as the hinge and bysuss ear are available) and that a number of previously described species variants may not be taxonomically valid. A biolog using the multivariate axis that best discriminates between species (CV1) and a random walk-based test using a Hurst estimate analysis indicate a gradualistic evolutionary mode for the Buchia species of Grassy Island. Shell shape and size of buchiids do not appear to be closely tied to lithofacies changes over the c. 10 myr time interval, suggesting that ecophenotypic variation (as it relates to substrate changes) probably had minimal influence on morphology. [ABSTRACT FROM AUTHOR]

1. Fish species are used globally for fundamental research, product and environmental testing, and education, but this use has not hitherto been documented. The number of fish used for research and education in North America currently represents approximately one-quarter of all animal use for these purposes; only mice are used in higher numbers. Data from the Canadian Council on Animal Care, various animal care committees from Canadian universities, and the United States Fish and Wildlife Service are collated and summarized. 2. In Canada nearly a half a million fish were used for research and education each year from 1996 to 2001. We estimated that the United States used over four times that amount for the same purposes, totalling approximately 2.8 million fish each year. 3. At least 100 fish species, representing 27 taxonomic orders, were used for research and education in North America from 1996 to 2001. Close to one-third of the species had life-history characteristics that might make them particularly susceptible to over-exploitation. This potential vulnerability, coupled with data from animal care facilities in Canada suggesting that nearly half of all fish used for research and education were wild-caught, should prompt further documentation of such fish uses in order to assess their sustainability. [ABSTRACT FROM AUTHOR]

The curio trade in marine fishes has not previously been quantitatively analysed. As a contribution towards understanding the scale and conservation impact of such trade we summarize import and export data from the United States Fish and Wildlife Service for 1997-2001. At least 32 fish species were involved in the USA's international trade in curios, of which 24 were included on the 2004 IUCN Red List of Threatened Species, with categorizations ranging from Endangered to Data Deficient. The USA apparently imported an annual total of approximately one million fish and 360 tonnes of fish parts, worth more than USD 1.7 million, although total volume declined over the 5 years of data. Fish curios imported to the USA reportedly came primarily from Taiwan and the Philippines, with 95% of curios obtained from wild populations. The three marine fish groups most traded for curios were sharks, seahorses and porcupinefishes. The value per individual fish fluctuated across years, with a considerable increase in the value of dried seahorses from 1997 to 2001. The trade probably adds to conservation concerns for at least some species. [ABSTRACT FROM AUTHOR]

Naticid gastropods leave a record of predation in the form of characteristic countersunk circular boreholes. We fed bivalve prey to naticids to test whether the ratio between the inner and outer borehole diameter differed among three Recent naticid species: Euspira heros, E. lewisii and Neverita duplicata. Fossil shells from a Miocene-aged assemblage, containing naticids previously identified as E. heros and N. duplicata, were also included in our analyses. Ratios of the inner to outer diameters of naticid boreholes in bivalve shells showed that there were significant differences in borehole shape between E. heros and the two other Recent species. We found no significant differences between the ratios of E. lewisii and N. duplicata; however, a principal component analysis showed that boreholes distinctly cluster according to species. The Miocene boreholes were also distinct from the Recent, indicating that the Miocene naticids may be a separate species from E. heros and N. duplicata. We have shown that there is a species-specific component to borehole geometry. This may have important implications for palaeobiological studies, because the index of borehole functionality, previously described as an inner to outer borehole ratio of 0.5 for all naticids, may differ between species. [ABSTRACT FROM AUTHOR]