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Fossil crinoids from the Ordovician–Silurian boundary interval (~ 443.8 million years) are known from relatively few locations worldwide due to a near-global unconformity that formed from eustatic sea-level fall. This rock record bias has severely hindered study of the timing, magnitude, biogeographic signature, and extinction mechanisms of the Late Ordovician mass extinction (LOME). Crinoids underwent a significant faunal transition between the Late Ordovician and early Silurian that resulted in major shifts between dominant clades, but the driving mechanisms and precise timing of this transition remain unclear. Anticosti Island (Québec, Canada) preserves one of the few Late Ordovician–early Silurian successions of highly fossiliferous, shallow-water rocks that includes the Ordovician–Silurian boundary, making fossils from this region instrumental for better understanding the LOME and Ordovician–Silurian crinoid faunal turnover.
Here we report on a new flexible crinoid, Anticosticrinus natiscotecensis n. gen. n. sp., from the Ordovician–Silurian boundary of Anticosti Island. Phylogenetic analysis of Middle Ordovician–early Silurian flexibles recovers Anticosticrinus natiscotecensis n. gen. n. sp. as a member of family Anisocrinidae. We quantified stratigraphic age uncertainty of A. natiscotecensis using a Bayesian approach for estimating tip-occurrence times in a phylogenetic context. Although results do not provide unequivocal support for the specimen’s precise stratigraphic age, the maximum a posteriori estimate indicates a late Hirnantian age. Regardless of its true age, recognition of Anticosticrinus natiscotecensis provides additional data for evaluating the timing of extinction in flexible crinoids, their diversification and increasing dominance during the Silurian, and crinoid faunal turnover between the Ordovician and Silurian.
The Paragaricocrinidae is an enigmatic late Paleozoic family of camerate crinoids that retained a robustly constructed calyx more typical of Devonian to Early Mississippian crinoids. The discovery of the oldest member of this family, Tuscumbiacrinus madisonensis n. gen. n. sp., initiated a phylogenetic investigation of the Paragaricocrinidae and consideration of its diversification and paleobiogeographic distribution. Phylogenetic analyses demonstrate the need to describe Tuscumbiacrinus n. gen and conduct revisions to preexisting taxa, resulting in the description of Palenciacrinus mudaensis n. gen. n. sp.; Pulcheracrinus n. gen.; Nipponicrinus hashimotoi n. gen. n. sp.; and Nipponicrinus akiyoshiensis n. gen. n. sp. Megaliocrinus exotericus Strimple is reassigned to Pulcheracrinus n. gen. In addition to having an anachronistic morphology, relatively few specimens are known through the ca. 76-million-year duration of this family. This pattern is unlikely to have resulted from low fossil sampling alone, and instead likely reflects low abundance and/or taxonomic richness of a long-lived waning clade. From its apparent origination in Laurussia during the Mississippian, the Paragaricocrinidae diversified into a cosmopolitan clade. Following a diversity drop during the Pennsylvanian, the Paragaricocrinidae persisted but exemplified characteristics of a dead clade walking until its eventual extinction during the middle Permian (Wordian).
Neuropsychiatric symptoms (NPS) can be observed in mild cognitive impairment (MCI) and dementia. Hallucinations are a core clinical symptom of Dementia with Lewy Bodies (DLB). In this study, we investigated NPS in healthy control and MCI groups who would later be diagnosed with DLB to determine which symptoms would present early.
Participants and Methods:
Participants included those originally diagnosed as healthy controls (n=55), MCI with DLB etiology (n=215), and DLB (n=1059). The control and MCI groups progressed to DLB at later visits in the study. NPS data were collected using the Neuropsychiatric Inventory Questionnaire (NPI-Q) that was obtained from the National Alzheimer's Coordinating Center.
Results:
To determine which NPS presented early in the DLB course, we ran ANCOVAs to assess the role of original diagnosis on each NPS, using age as a covariate and applying Bonferroni correction. The control and MCI groups, who were later diagnosed with DLB, had greater severity of delusions, hallucinations, agitation, and apathy than the DLB group. The MCI group that would later be diagnosed with DLB had greater severity of anxiety and motor symptoms than the DLB group. The control group had greater irritability severity than the DLB group, and the controls had greater nighttime behavior severity than the MCI group, who had greater severity than the DLB group.
Conclusions:
Overall, we found that NPS present early in those who will be diagnosed with DLB, even when they are diagnosed as healthy controls. These results suggest that examination of NPS is important even in healthy adults, and their presence may be the onset of the DLB process before an official diagnosis of the condition.
The U.S. Department of Agriculture–Agricultural Research Service (USDA-ARS) has been a leader in weed science research covering topics ranging from the development and use of integrated weed management (IWM) tactics to basic mechanistic studies, including biotic resistance of desirable plant communities and herbicide resistance. ARS weed scientists have worked in agricultural and natural ecosystems, including agronomic and horticultural crops, pastures, forests, wild lands, aquatic habitats, wetlands, and riparian areas. Through strong partnerships with academia, state agencies, private industry, and numerous federal programs, ARS weed scientists have made contributions to discoveries in the newest fields of robotics and genetics, as well as the traditional and fundamental subjects of weed–crop competition and physiology and integration of weed control tactics and practices. Weed science at ARS is often overshadowed by other research topics; thus, few are aware of the long history of ARS weed science and its important contributions. This review is the result of a symposium held at the Weed Science Society of America’s 62nd Annual Meeting in 2022 that included 10 separate presentations in a virtual Weed Science Webinar Series. The overarching themes of management tactics (IWM, biological control, and automation), basic mechanisms (competition, invasive plant genetics, and herbicide resistance), and ecosystem impacts (invasive plant spread, climate change, conservation, and restoration) represent core ARS weed science research that is dynamic and efficacious and has been a significant component of the agency’s national and international efforts. This review highlights current studies and future directions that exemplify the science and collaborative relationships both within and outside ARS. Given the constraints of weeds and invasive plants on all aspects of food, feed, and fiber systems, there is an acknowledged need to face new challenges, including agriculture and natural resources sustainability, economic resilience and reliability, and societal health and well-being.
The Hierarchical Taxonomy of Psychopathology (HiTOP) has emerged out of the quantitative approach to psychiatric nosology. This approach identifies psychopathology constructs based on patterns of co-variation among signs and symptoms. The initial HiTOP model, which was published in 2017, is based on a large literature that spans decades of research. HiTOP is a living model that undergoes revision as new data become available. Here we discuss advantages and practical considerations of using this system in psychiatric practice and research. We especially highlight limitations of HiTOP and ongoing efforts to address them. We describe differences and similarities between HiTOP and existing diagnostic systems. Next, we review the types of evidence that informed development of HiTOP, including populations in which it has been studied and data on its validity. The paper also describes how HiTOP can facilitate research on genetic and environmental causes of psychopathology as well as the search for neurobiologic mechanisms and novel treatments. Furthermore, we consider implications for public health programs and prevention of mental disorders. We also review data on clinical utility and illustrate clinical application of HiTOP. Importantly, the model is based on measures and practices that are already used widely in clinical settings. HiTOP offers a way to organize and formalize these techniques. This model already can contribute to progress in psychiatry and complement traditional nosologies. Moreover, HiTOP seeks to facilitate research on linkages between phenotypes and biological processes, which may enable construction of a system that encompasses both biomarkers and precise clinical description.
Fossil crinoids are exceptionally suited to deep-time studies of community paleoecology and niche partitioning. By merging ecomorphological trait and phylogenetic data, this Element summarizes niche occupation and community paleoecology of crinoids from the Bromide fauna of Oklahoma (Sandbian, Upper Ordovician). Patterns of community structure and niche evolution are evaluated over a ~5 million-year period through comparison with the Brechin Lagerstätte (Katian, Upper Ordovician). The authors establish filtration fan density, food size selectivity, and body size as major axes defining niche differentiation, and niche occupation is strongly controlled by phylogeny. Ecological strategies were relatively static over the study interval at high taxonomic scales, but niche differentiation and specialization increased in most subclades. Changes in disparity and species richness indicate the transition between the early-middle Paleozoic Crinoid Evolutionary Faunas was already underway by the Katian due to ecological drivers and was not triggered by the Late Ordovician mass extinction.
Macroevolutionary inference has historically been treated as a two-step process, involving the inference of a tree, and then inference of a macroevolutionary model using that tree. Newer models blend the two steps. These methods make more complete use of fossils than the previous generation of Bayesian phylogenetic models. They also involve many more parameters than prior models, including parameters about which empiricists may have little intuition. In this Element, we set forth a framework for fitting complex, hierarchical models. The authors ultimately fit and use a joint tree and diversification model to estimate a dated phylogeny of the Cincta (Echinodermata), a morphologically distinct group of Cambrian echinoderms that lack the fivefold radial symmetrycharacteristic of extant members of the phylum. Although the phylogeny of cinctans remains poorly supported in places, this Element shows how models of character change and diversification contribute to understanding patterns of phylogenetic relatedness and testing macroevolutionary hypotheses.
Recent advances in statistical approaches called phylogenetic comparative methods (PCMs) have provided paleontologists with a powerful set of analytical tools for investigating evolutionary tempo and mode in fossil lineages. However, attempts to integrate PCMs with fossil data often present workers with practical challenges or unfamiliar literature. This Element presents guides to the theory behind and the application of PCMs with fossil taxa. Based on an empirical dataset of Paleozoic crinoids, example analyses are presented to illustrate common applications of PCMs to fossil data, including investigating patterns of correlated trait evolution and macroevolutionary models of morphological change. The authors emphasize the importance of accounting for sources of uncertainty and discuss how to evaluate model fit and adequacy. Finally, the authors discuss several promising methods for modeling heterogeneous evolutionary dynamics with fossil phylogenies. Integrating phylogeny-based approaches with the fossil record provides a rigorous, quantitative perspective on understanding key patterns in the history of life.
The Brechin Lagerstätte of southern Ontario contains an exceptionally diverse and well-preserved Late Ordovician (Katian) crinoid fauna. We describe four genera and eight species of camerate crinoids from the Brechin Lagerstätte, including six new species. Consequently, the total diversity of the fauna now stands at 27 genera and 39 nominal species, thereby making it the most taxonomically diverse Ordovician crinoid fauna known. Taxa described include the diplobathrid Pararchaeocrinus kiddi new species and the monobathrids Glyptocrinus ramulosus Billings, 1856, Periglyptocrinus priscus (Billings, 1857a), Periglyptocrinus astricus new species, Periglyptocrinus kevinbretti new species, Periglyptocrinus mcdonaldi new species, Periglyptocrinus silvosus new species, and Abludoglyptocrinus steinheimerae new species. We summarize the taxonomic composition, diversity, and abundance distribution of all known crinoids from the Brechin Lagerstätte to better characterize the paleoecological structure and complexity of the community. We establish that the fauna is dominated by the subclass Pentacrinoidea, both in terms of abundance and species richness. In addition, we analyze species-level abundance data using Relative Abundance Distribution (RAD) models to evaluate the ecological complexity of the paleocommunity. We found that community structure of the Brechin Lagerstätte is best explained by an ecologically ‘complex’ RAD model, which suggests that species partitioned niches along multiple resource axes and/or the presence of multiple ecological ways of life. These results indicate that the Brechin Lagerstätte is significant not only for being the most taxonomically diverse Katian crinoid assemblage, but also for being an early ecologically complex fauna that developed in the wake of the Great Ordovician Biodiversification Event.
Upper Ordovician (Katian) strata of the Lake Simcoe region of Ontario record a spectacularly diverse and abundant echinoderm fauna known as the Brechin Lagerstätte. Despite recognition as the most taxonomically diverse Katian crinoid paleocommunity, the Brechin Lagerstätte has received relatively little taxonomic study since Frank Springer published his classic monograph on the “Kirkfield fauna” in 1911.
Using a new collection of exceptionally preserved material, we evaluate all dicyclic inadunate crinoids occurring in the Brechin Lagerstätte, which is predominantly comprised of cladids (Eucladida and Flexibilia). We document 15 species across 11 genera, including descriptions of two new genera and four new species. New taxa include Konieckicrinus brechinensis n. gen. n. sp., K. josephi n. gen. n. sp., Simcoecrinus mahalaki n. gen. n. sp., and Dendrocrinus simcoensis n. sp.
Although cladids are not commonly considered major components of the Early Paleozoic Crinoid Macroevolutionary Fauna, which is traditionally conceived as dominated by disparids and diplobathrid camerates, they are the most diverse major lineage of crinoids occurring in the Brechin Lagerstätte. This unexpected result highlights the important roles of specimen-based taxonomy and systematic revisions in the study of large-scale diversity patterns.
The Brechin Lagerstätte (Katian, Ordovician) from the Lake Simcoe region of Ontario, Canada contains a diverse array of echinoderms. Here, we describe seven disparid and two hybocrinid crinoids (subclass Pentacrinoidea, infraclass Inadunata), including a new disparid species belonging to the Anomalocrinidae (order Homocrinida). In total, the disparids include Anomalocrinus astrictus n. sp.; Cremacrinus guttenbergensis Kolata, 1975; C. inaequalis Billings, 1859; Daedalocrinus bellevillensis Billings, 1883; Eustenocrinus springeri Ulrich, 1925; Iocrinus trentonensis Walcott, 1883; and Isotomocrinus tenuis Billings, 1857b. The hybocrinids include Hybocrinus tumidus Billings, 1857a and Hybocystites problematicus Wetherby, 1880. Previously known from only the holotype, three additional specimens of E. springeri expand our understanding of this unusual crinoid. Nomenclatural acts include: (1) the recommended designation of D. kirki Ulrich, 1925 as a junior synonym of D. bellevillensis is followed; (2) Hybocrinus pristinus Billings, 1858 is designated as a junior synonym of H. tumidus, and previous decisions are followed to retain Hybocystites eldonensis (Parks, 1908) as a junior synonym of H. problematicus; (3) although probably assignable to Anomalocrinus Meek and Worthen, 1865, the aberrant crinoid Glaucocrinus falconeri Parks and Alcock, 1912, and its genus Glaucocrinus Parks and Alcock, 1912, are designated as nomena dubia; (4) Iocrinus similis (Billings, 1857) is also designated as a nomen dubium; and (5) Iocrinus subcrassus torontoensis Fritz, 1925 is designated a junior synonym of I. subcrassus Meek and Worthen, 1865.
The Upper Ordovician (lower Katian) Bobcaygeon and Verulam formations from the Lake Simcoe region of Ontario contain a highly diverse echinoderm assemblage that is herein recognized as a Konservat-Lagerstätte. Although fossil crinoids have long been recognized from these formations, the fauna has not received a comprehensive taxonomic evaluation since Springer’s classic 1911 monograph. Recent extensive collection and preparation of new material from the Bobcaygeon and Verulam formations near Brechin, Ontario recovered numerous exceptionally preserved crinoid specimens with arms, stems, and attachment structures intact. The Brechin Lagerstätte is the most taxonomically diverse Katian crinoid fauna, with more than 20 crinoid genera represented in this collection.
Here, all dicyclic crinoids belonging to subclass Camerata from the Brechin Lagerstätte are evaluated. The following four genera and seven species are described from the fauna, including one new genus and four new species: Reteocrinus stellaris, Reteocrinus alveolatus, Archaeocrinus sundayae n. sp., Archaeocrinus maraensis n. sp., Priscillacrinus elegans n. gen. n. sp., Cleiocrinus regius, and Cleiocrinus lepidotus n. sp. The exceptional preservation of this collection provides an opportunity to describe more fully the morphologic and ontogenetic details of known Ordovician crinoid taxa, to conduct a taxonomic re-evaluation of many species, to describe new taxa, and to provide a framework for subsequent studies of crinoid community paleoecology.
A major goal of biological classification is to provide a system that conveys phylogenetic relationships while facilitating lucid communication among researchers. Phylogenetic taxonomy is a useful framework for defining clades and delineating their taxonomic content according to well-supported phylogenetic hypotheses. The Crinoidea (Echinodermata) is one of the five major clades of living echinoderms and has a rich fossil record spanning nearly a half billion years. Using principles of phylogenetic taxonomy and recent phylogenetic analyses, we provide the first phylogeny-based definition for the Clade Crinoidea and its constituent subclades. A series of stem- and node-based definitions are provided for all major taxa traditionally recognized within the Crinoidea, including the Camerata, Disparida, Hybocrinida, Cladida, Flexibilia, and Articulata. Following recommendations proposed in recent revisions, we recognize several new clades, including the Eucamerata Cole 2017, Porocrinoidea Wright 2017, and Eucladida Wright 2017. In addition, recent phylogenetic analyses support the resurrection of two names previously abandoned in the crinoid taxonomic literature: the Pentacrinoidea Jaekel, 1918 and Inadunata Wachsmuth and Springer, 1885. Last, a phylogenetic perspective is used to inform a comprehensive revision of the traditional rank-based classification. Although an attempt was made to minimize changes to the rank-based system, numerous changes were necessary in some cases to achieve monophyly. These phylogeny-based classifications provide a useful template for paleontologists, biologists, and non-experts alike to better explore evolutionary patterns and processes with fossil and living crinoids.
Knowledge of phylogenetic relationships among species is fundamental to understanding basic patterns in evolution and underpins nearly all research programs in biology and paleontology. However, most methods of phylogenetic inference typically used by paleontologists do not accommodate the idiosyncrasies of fossil data and therefore do not take full advantage of the information provided by the fossil record. The advent of Bayesian ‘tip-dating’ approaches to phylogeny estimation is especially promising for paleosystematists because time-stamped comparative data can be combined with probabilistic models tailored to accommodate the study of fossil taxa. Under a Bayesian framework, the recently developed fossilized birth–death (FBD) process provides a more realistic tree prior model for paleontological data that accounts for macroevolutionary dynamics, preservation, and sampling when inferring phylogenetic trees containing fossils. In addition, the FBD tree prior allows for the possibility of sampling ancestral morphotaxa. Although paleontologists are increasingly embracing probabilistic phylogenetic methods, these recent developments have not previously been applied to the deep-time invertebrate fossil record. Here, I examine phylogenetic relationships among Ordovician through Devonian crinoids using a Bayesian tip-dating approach. Results support several clades recognized in previous analyses sampling only Ordovician taxa, but also reveal instances where phylogenetic affinities are more complex and extensive revisions are necessary, particularly among the Cladida. The name Porocrinoidea is proposed for a well-supported clade of Ordovician ‘cyathocrine’ cladids and hybocrinids. The Eucladida is proposed as a clade name for the sister group of the Flexibilia herein comprised of cladids variously considered ‘cyathocrines,’ ‘dendrocrines,’ and/or ‘poteriocrines’ by other authors.
A sensitive search has been made for OH maser emission from a sample of 16 symbiotic stars. This sample has been selected on the basis of infrared optical depth and variability, so that the stars within it have circumstellar shells similar to those seen in the well-known OH/IR and OH/Mira stars. There were no significant detections, except for one unassociated background source, and we conclude that the presence of a hot binary companion inhibits any possible OH maser action.
Paleobiologists must propose a priori hypotheses of homology when conducting a phylogenetic analysis of extinct taxa. The distributions of such “primary” homologies among species are fundamental to phylogeny reconstruction because they reflect a prior belief in what constitutes comparable organismal elements and are the principal determinants of the outcome of phylogenetic analysis. Problems arise when fossil morphology presents seemingly equivocal hypotheses of homology, herein referred to as antinomies. In groups where homology recognition has been elusive, such as echinoderms, these problems are commonly accompanied by the presence (and persistence) of poor descriptive terminology in taxonomic literature that confounds an understanding of characters and stymy phylogenetic research. This paper combines fossil morphology, phylogenetic systematics, and insights from evolutionary developmental biology to outline a research program in Phylogenetic Paleo-ontogeny. A “paleo” ontogenetic approach to character analysis provides a logical basis for homology recognition and discerning patterns of character evolution in a phylogenetic context. To illustrate the utility of the paleo-ontogenetic approach, I present a reassessment of historically contentious plate homologies for “pan-cladid” crinoids (Cladida, Flexibilia, Articulata). Developmental patterns in living crinoids were combined with the fossil record of pan-cladid morphologies to investigate primary posterior plate homologies. Results suggest the sequence of morphologic transitions unfolding during the ontogeny of extant crinoids are developmental relics of their Paleozoic precursors. Developmental genetic modules controlling posterior plate development in pan-cladid crinoids have likely experienced considerable constraint for over 250 million years and limited morphologic diversity in the complexity of calyx characters. Future phylogenetic analyses of pan-cladids are recommended to consider the presence of a single plate in the posterior region homologous with the radianal, rather than the anal X, as is commonly assumed.
The orthidine brachiopod genera Plaesiomys and Hebertella are significant constituents of Late Ordovician benthic marine communities throughout Laurentia. Species-level phylogenetic analyses were conducted on both genera to inform systematic revisions and document evolutionary relationships. Phylogenetic analyses combined discrete and continuous characters, from which character states were determined using a statistical approach, and utilized both cladistic and Bayesian methodologies. Plaesiomys cutterensis, P. idahoensis, and P. occidentalis are herein recognized as distinct species rather than subspecies of P. subquadratus. Similarly, Hebertella montoyensis and H. prestonensis are recognized as distinct species separate from H. occidentalis, and H. richmondensis is recognized as a distinct species rather than a geographical variant of H. alveata. Hebertella subjugata is removed from its tentative synonymy with H. occidentalis and revalidated.
The development of species-level evolutionary hypotheses for Plaesiomys and Hebertella provides a detailed framework for assessing evolutionary and paleobiogeographic patterns of Late Ordovician brachiopods from Laurentia. The geographic range of Hebertella expanded throughout Laurentia during the Richmondian into both intracratonic and marginal basins. Plaesiomys subquadratus participated in the Late Ordovician Richmondian Invasion. The recovered phylogenetic topology for Plaesiomys suggests that P. subquadratus may have migrated into the Cincinnati region from a basin situated to the paleo-northeast.
Two new specimens of a trigonotarbid arachnid are described from Upper Pennsylvanian (Virgilian) rocks of Kansas, U.S.A., from a horizon which elsewhere has yielded scorpion and mite remains. They are the first representatives of the arachnid order Trigonotarbida to be found in Kansas. The specimens are referred to the genus Anthracomartus but are not identified to species pending revision of the American anthracomartids.
Variation in human cognitive ability is of consequence to a large number of health and social outcomes and is substantially heritable. Genetic linkage, genome-wide association, and copy number variant studies have investigated the contribution of genetic variation to individual differences in normal cognitive ability, but little research has considered the role of rare genetic variants. Exome sequencing studies have already met with success in discovering novel trait-gene associations for other complex traits. Here, we use exome sequencing to investigate the effects of rare variants on general cognitive ability. Unrelated Scottish individuals were selected for high scores on a general component of intelligence (g). The frequency of rare genetic variants (in n = 146) was compared with those from Scottish controls (total n = 486) who scored in the lower to middle range of the g distribution or on a proxy measure of g. Biological pathway analysis highlighted enrichment of the mitochondrial inner membrane component and apical part of cell gene ontology terms. Global burden analysis showed a greater total number of rare variants carried by high g cases versus controls, which is inconsistent with a mutation load hypothesis whereby mutations negatively affect g. The general finding of greater non-synonymous (vs. synonymous) variant effects is in line with evolutionary hypotheses for g. Given that this first sequencing study of high g was small, promising results were found, suggesting that the study of rare variants in larger samples would be worthwhile.
Gram-negative bacilli frequently cause epidemics in high-risk newborn intensive care units. Recently, an epidemic caused by a multiply-resistant K. pneumoniae, serotype 21, occurred in the Vanderbilt University intensive care nursery. The background of this outbreak included an increasing endemic nosocomial sepsis rate, operation of the facility in excess of rated capacity, and increasingly inadequate nurse-to-patient staffing ratios. The epidemic lasted 11 weeks; 26 (12%) of the 232 infants at risk in the unit became colonized. Five infants developed systemic illness and one died. Cohorting, reinforcement of strict handwashing and isolation procedures, and closure of the unit to outborn admissions resulted in rapid termination of the outbreak. Followup studies performed on infants colonized with the epidemic bacterium demonstrated persistent fecal shedding up to 13 months following discharge from the hospital. This epidemic had a detrimental influence on high-risk newborn and obstetric health care delivery in an area encompassing portions of three states. Under a system of progressively more sophisticated referral units, nosocomial infections occurring at a tertiary center can have an impact on other hospitals within the network.