Lower Cambrian Peel, John S; Skovsted, Christian B
Canadian journal of earth sciences,
06/2021, Letnik:
58, Številka:
6
Journal Article
Recenzirano
Three small assemblages of lower Cambrian (Cambrian Series 2, Stage 4) small shelly fossils are described from Laurentian strata astride Nares Strait. The fauna from the Humboldt Formation of ...Daugaard-Jensen Land, North Greenland, is derived from inner shelf sediments deposited on the stable craton of the Inglefield Land High. Fossils from Judge Daly Promontory, eastern Ellesmere Island, Nunavut, occur in strata of the Cambrian Ellesmere Group (Kane Basin Formation) that have been structurally juxtaposed against older strata; they were originally assigned to the Kennedy Channel Formation, which is now considered to be of Neoproterozoic age. A similar fauna from offshore environments of the Aftenstjerneso Formation in northern Nyeboe Land, North Greenland, reflects the regional structural and sedimentological continuity with the Canadian Cambrian succession. Pojetaia robsonae sp.nov.is described from Judge Daly Promontory.
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Although multituberculates are among the best-represented mammals of the Late Cretaceous and early Paleogene in North America, their evolution during the first several tens to hundreds of thousands ...of years following the Cretaceous--Paleogene (K--Pg) impact event is largely obscure. A better understanding of the early Paleogene record of multituberculates is crucial, for their dominance in early Paleocene mammalian faunas is unquestionably a result of rapid evolution during the immediate post-impact interval, and they accordingly played an important role in the evolution of mammalian communities more generally. I report on a new multituberculate from the early Paleocene of southwestern Alberta, in rocks of the Willow Creek Formation, the first such occurrence in this otherwise poorly known unit. The new multituberculate, Aenigmamys aries gen. et sp. nov., most closely resembles the ptilodontid Kimbetohia campi in comparable parts of the dentition and sheds light on the early evolution of Ptilodontidae, one of the major cimolodontan families that diversified during the Paleocene. The presence of Aenigmamys in mammalian faunas that lived soon after the K--Pg boundary implies a still-deeper evolutionary history for Ptilodontidae that may have extended into the Late Cretaceous. Aenigmamys is part of a new mammalian fauna from southwestern Alberta, the taxonomic composition of which includes a diversity of multituberculates, cimolestans, primates, and condylarths. The fauna correlates with those of middle Puercan age from other parts of the Western Interior of North America, and its high taxonomic diversity further corroborates previous hypotheses that multituberculate recovery--and mammalian recovery more generally--occurred relatively quickly after the K--Pg extinction event.
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Can reading, writing about, and teaching Shakespeare contribute to the health of the planet? To what degree are Shakespeare's plays anthropocentric or ecocentric? What is the connection between the ...literary and the real when it comes to ecological conduct? This collection, engages with these pressing questions surrounding ecocritical Shakespeare, in order to provide a better understanding of where and how ecocritical readings should be situated. The volume combines multiple critical perspectives, juxtaposing historicism and presentism, as well as considering ecofeminism and pedagogy; and addresses such topics as early modern flora and fauna, and the neglected areas of early modern marine ecology and oceanography. Concluding with an assessment of the challenges-and necessities-of teaching Shakespeare ecocritically, Ecocritical Shakespeare not only broadens the implications of ecocriticism in early modern studies, but represents an important contribution to this growing field.
This book explores the streets, shops, back alleys, and gardens of Elizabethan London, where a boisterous and diverse group of men and women shared a keen interest in the study of nature. These ...assorted merchants, gardeners, barber-surgeons, midwives, instrument makers, mathematics teachers, engineers, alchemists, and other experimenters Deborah Harkness contends formed a patchwork scientific community whose practices set the stage for the Scientific Revolution. While Francis Bacon has been widely regarded as the father of modern science, scores of his London contemporaries also deserve a share in this distinction. It was their collaborative, yet often contentious, ethos that helped to develop the ideals of modern scientific research.
The book examines six particularly fascinating episodes of scientific inquiry and dispute in sixteenth-century London, bringing to life the individuals involved and the challenges they faced. These men and women experimented and invented, argued and competed, waged wars in the press, and struggled to understand the complexities of the natural world. Together their stories illuminate the blind alleys and surprising twists and turns taken as medieval philosophy gave way to the empirical, experimental culture that became a hallmark of the Scientific Revolution.
Specimens of plants and animals preserved in museums are the primary source of verifiable data on the geographical and temporal distribution of organisms. Museum datasets are increasingly being ...uploaded to aggregated regional and global databases (e.g. the Global Biodiversity Information Facility; GBIF) for use in a wide range of analyses 1. Thus, digitisation of natural history collections is providing unprecedented information to facilitate the study of the natural world on a global scale. The digitisation of this information utilises information provided on specimen labels, and assumes they are correctly identified. Here we evaluate the accuracy of names associated with 4,500 specimens of African gingers from 40 herbaria in 21 countries. Our data show that at least 58% of the specimens had the wrong name prior to a recent taxonomic study. A similar pattern of wrongly named specimens is also shown for Dipterocarps and Ipomoea (morning glory). We also examine the number of available plant specimens worldwide. Our data demonstrate that, while the world’s collections have more than doubled since 1970, more than 50% of tropical specimens, on average, are likely to be incorrectly named. This finding has serious implications for the uncritical use of specimen data from natural history collections.
Genomic analysis reveals that many tropical plant specimens in natural history collections were misidentified.
None of the approximately 750,000 known asteroids and comets in the Solar System is thought to have originated outside it, despite models of the formation of planetary systems suggesting that orbital ...migration of giant planets ejects a large fraction of the original planetesimals into interstellar space. The high predicted number density of icy interstellar objects (2.4 × 10
per cubic astronomical unit) suggests that some should have been detected, yet hitherto none has been seen. Many decades of asteroid and comet characterization have yielded formation models that explain the mass distribution, chemical abundances and planetary configuration of the Solar System today, but there has been no way of telling whether the Solar System is typical of planetary systems. Here we report observations and analysis of the object 1I/2017 U1 ('Oumuamua) that demonstrate its extrasolar trajectory, and that thus enable comparisons to be made between material from another planetary system and from our own. Our observations during the brief visit by the object to the inner Solar System reveal it to be asteroidal, with no hint of cometary activity despite an approach within 0.25 astronomical units of the Sun. Spectroscopic measurements show that the surface of the object is spectrally red, consistent with comets or organic-rich asteroids that reside within the Solar System. Light-curve observations indicate that the object has an extremely oblong shape, with a length about ten times its width, and a mean radius of about 102 metres assuming an albedo of 0.04. No known objects in the Solar System have such extreme dimensions. The presence of 'Oumuamua in the Solar System suggests that previous estimates of the number density of interstellar objects, based on the assumption that all such objects were cometary, were pessimistically low. Planned upgrades to contemporary asteroid survey instruments and improved data processing techniques are likely to result in the detection of more interstellar objects in the coming years.
Nature on the Doorstep reveals the simple pleasures of paying attention to the natural world in one's own backyard over the course of a year. In weekly letters, Angela Douglas shares the joys and ...curiosities of a decidedly ordinary patch of green in upstate New York cultivated through the art of strategic neglect—sometimes taking a hand to manage wildlife, more often letting nature go its own way. From the first flowers of spring to cardinals singing in the winter, Douglas shows us the magic of welcoming unexpected plant and animal life into one's backyard. A paean to the richness we find when we stop to look and let be, Nature on the Doorstep celebrates the role humble backyards play both in conservation efforts and in an expanded appreciation of the living world.
Articulating dinosaurs Noble, Brian
Articulating dinosaurs,
2016, 2016, 2016-08-08
eBook
"In this remarkable interdisciplinary study, anthropologist Brian Noble traces how dinosaurs and their natural worlds are articulated into being by the action of specimens and humans together. ...Following the complex exchanges of palaeontologists, museums specialists, film- and media-makers, science fiction writers, and their diverse publics, he witnesses how fossil remains are taken from their partial state and re-composed into astonishingly precise, animated presences within the modern world, with profound political consequences."--
"Articulating Dinosaurs examines the resurrecting of two of the most iconic and gendered of dinosaurs. First Noble traces the emergence of Tyrannosaurus rex (the "king of the tyrant lizards") in the early twentieth-century scientific, literary, and filmic cross-currents associated with the American Museum of Natural History under the direction of palaeontologist and eugenicist Henry Fairfield Osborn. Then he offers his detailed ethnographic study of the multi-media, model-making, curatorial, and laboratory preparation work behind the Royal Ontario Museum's ground-breaking 1990s exhibit of Maiasaura (the "good mother lizard"). Setting the exhibits at the AMNH and the ROM against each other, Noble is able to place the political natures of T. rex and Maiasaura into high relief and to raise vital questions about how our choices make a difference in what comes to count as "nature." An original and illuminating study of science, culture, and museums, Articulating Dinosaurs is a remarkable look at not just how we visualize the prehistoric past, but how we make it palpable it our everyday lives."--
The Crato Formation (Araripe Basin) preserves one of the most diverse entomofaunas of the Cretaceous. Among the groups of insects, mayflies stand out in abundance, but among them oligoneuriids are ...especially rare. A newly discovered adult oligoneuriid from this unit is here described as Incogemina nubila gen. et sp. nov. and new subfamily Incogemininae. A phylogenetic analysis recovered the new taxon as the sister group to the species-rich and cosmopolitan Oligoneuriinae. The paratype of Colocrus indivicum, described as an "oligoneuriid" from the same unit, is here reviewed and considered as belonging to the family Hexagenitidae. The biogeographical and taxonomic implications of this discovery and the phylogenetic position of Incogemina nubila are discussed. Incogemina bridge an important morphological gap between the Oligoneuriinae and the extant Chromarcys. Also, it demonstrates that the divergence between Oligoneuriinae and Incogemininae probably occurred in South America.
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