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Beeston SL, Poropat SF, Mannion PD, Pentland AH, Enchelmaier MJ, Sloan T, Elliott DA. Reappraisal of sauropod dinosaur diversity in the Upper Cretaceous Winton Formation of Queensland, Australia, through 3D digitisation and description of new specimens. PeerJ 2024; 12:e17180. [PMID: 38618562 PMCID: PMC11011616 DOI: 10.7717/peerj.17180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Accepted: 03/11/2024] [Indexed: 04/16/2024] Open
Abstract
Skeletal remains of sauropod dinosaurs have been known from Australia for over 100 years. Unfortunately, the classification of the majority of these specimens to species level has historically been impeded by their incompleteness. This has begun to change in the last 15 years, primarily through the discovery and description of several partial skeletons from the Cenomanian-lower Turonian (lower Upper Cretaceous) Winton Formation in central Queensland, with four species erected to date: Australotitan cooperensis, Diamantinasaurus matildae, Savannasaurus elliottorum, and Wintonotitan wattsi. The first three of these appear to form a clade (Diamantinasauria) of early diverging titanosaurs (or close relatives of titanosaurs), whereas Wintonotitan wattsi is typically recovered as a distantly related non-titanosaurian somphospondylan. Through the use of 3D scanning, we digitised numerous specimens of Winton Formation sauropods, facilitating enhanced comparison between type and referred specimens, and heretofore undescribed specimens. We present new anatomical information on the holotype specimen of Diamantinasaurus matildae, and describe new remains pertaining to twelve sauropod individuals. Firsthand observations and digital analysis enabled previously proposed autapomorphic features of all four named Winton Formation sauropod species to be identified in the newly described specimens, with some specimens exhibiting putative autapomorphies of more than one species, prompting a reassessment of their taxonomic validity. Supported by a specimen-level phylogenetic analysis, we suggest that Australotitan cooperensis is probably a junior synonym of Diamantinasaurus matildae, but conservatively regard it herein as an indeterminate diamantinasaurian, meaning that the Winton Formation sauropod fauna now comprises three (rather than four) valid diamantinasaurian species: Diamantinasaurus matildae, Savannasaurus elliottorum, and Wintonotitan wattsi, with the latter robustly supported as a member of the clade for the first time. We refer some of the newly described specimens to these three species and provide revised diagnoses, with some previously proposed autapomorphies now regarded as diamantinasaurian synapomorphies. Our newly presented anatomical data and critical reappraisal of the Winton Formation sauropods facilitates a more comprehensive understanding of the mid-Cretaceous sauropod palaeobiota of central Queensland.
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Affiliation(s)
- Samantha L. Beeston
- Department of Earth Sciences, University College London, University of London, London, United Kingdom
- Faculty of Science, Engineering and Technology, Swinburne University of Technology, Hawthorn, Victoria, Australia
- Australian Age of Dinosaurs Museum of Natural History, Winton, Queensland, Australia
| | - Stephen F. Poropat
- Western Australian Organic and Isotope Geochemistry Centre, School of Earth and Planetary Science, Curtin University of Technology, Bentley, Western Australia, Australia
| | - Philip D. Mannion
- Department of Earth Sciences, University College London, University of London, London, United Kingdom
| | - Adele H. Pentland
- Australian Age of Dinosaurs Museum of Natural History, Winton, Queensland, Australia
- Western Australian Organic and Isotope Geochemistry Centre, School of Earth and Planetary Science, Curtin University of Technology, Bentley, Western Australia, Australia
| | | | - Trish Sloan
- Australian Age of Dinosaurs Museum of Natural History, Winton, Queensland, Australia
| | - David A. Elliott
- Australian Age of Dinosaurs Museum of Natural History, Winton, Queensland, Australia
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2
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Perillo M, Sander PM. The dinosaurs that weren't: osteohistology supports giant ichthyosaur affinity of enigmatic large bone segments from the European Rhaetian. PeerJ 2024; 12:e17060. [PMID: 38618574 PMCID: PMC11011611 DOI: 10.7717/peerj.17060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Accepted: 02/15/2024] [Indexed: 04/16/2024] Open
Abstract
Very large unidentified elongate and rounded fossil bone segments of uncertain origin recovered from different Rhaetian (Late Triassic) fossil localities across Europe have been puzzling the paleontological community since the second half of the 19th century. Different hypotheses have been proposed regarding the nature of these fossils: (1) giant amphibian bones, (2) dinosaurian or other archosaurian long bone shafts, and (3) giant ichthyosaurian jaw bone segments. We call the latter proposal the 'Giant Ichthyosaur Hypothesis' and test it using bone histology. In presumable ichthyosaur specimens from SW England (Lilstock), France (Autun), and indeterminate cortical fragments from Germany (Bonenburg), we found a combination of shared histological features in the periosteal cortex: an unusual woven-parallel complex of strictly longitudinal primary osteons set in a novel woven-fibered matrix type with intrinsic coarse collagen fibers (IFM), and a distinctive pattern of Haversian substitution in which secondary osteons often form within primary ones. The splenial and surangular of the holotype of the giant ichthyosaur Shastasaurus sikanniensis from Canada were sampled for comparison. The results of the sampling indicate a common osteohistology with the European specimens. A broad histological comparison is provided to reject alternative taxonomic affinities aside from ichthyosaurs of the very large bone segment. Most importantly, we highlight the occurrence of shared peculiar osteogenic processes in Late Triassic giant ichthyosaurs, reflecting special ossification strategies enabling fast growth and achievement of giant size and/or related to biomechanical properties akin to ossified tendons.
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Affiliation(s)
- Marcello Perillo
- Section Paleontology, Institute of Geosciences, Rheinische Friedrich-Wilhelms Universität Bonn, Bonn, Germany
| | - P Martin Sander
- Section Paleontology, Institute of Geosciences, Rheinische Friedrich-Wilhelms Universität Bonn, Bonn, Germany
- The Dinosaur Institute, Natural History Museum of Los Angeles County, Los Angeles, CA, United States of America
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3
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Wilson LN, Gardner JD, Wilson JP, Farnsworth A, Perry ZR, Druckenmiller PS, Erickson GM, Organ CL. Global latitudinal gradients and the evolution of body size in dinosaurs and mammals. Nat Commun 2024; 15:2864. [PMID: 38580657 PMCID: PMC10997647 DOI: 10.1038/s41467-024-46843-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Accepted: 03/12/2024] [Indexed: 04/07/2024] Open
Abstract
Global climate patterns fundamentally shape the distribution of species and ecosystems. For example, Bergmann's rule predicts that homeothermic animals, including birds and mammals, inhabiting cooler climates are generally larger than close relatives from warmer climates. The modern world, however, lacks the comparative data needed to evaluate such macroecological rules rigorously. Here, we test for Bergmann's rule in Mesozoic dinosaurs and mammaliaforms that radiated within relatively temperate global climate regimes. We develop a phylogenetic model that accounts for biases in the fossil record and allows for variable evolutionary dispersal rates. Our analysis also includes new fossil data from the extreme high-latitude Late Cretaceous Arctic Prince Creek Formation. We find no evidence for Bergmann's rule in Mesozoic dinosaurs or mammaliaforms, the ancestors of extant homeothermic birds and mammals. When our model is applied to thousands of extant dinosaur (bird) and mammal species, we find that body size evolution remains independent of latitude. A modest temperature effect is found in extant, but not in Mesozoic, birds, suggesting that body size evolution in modern birds was influenced by Bergmann's rule during Cenozoic climatic change. Our study provides a general approach for studying macroecological rules, highlighting the fossil record's power to address longstanding ecological principles.
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Affiliation(s)
- Lauren N Wilson
- University of Alaska Museum, 1962 Yukon Drive, Fairbanks, AK, 99775, USA.
- Department of Geosciences, University of Alaska, Fairbanks, AK, 99775, USA.
| | - Jacob D Gardner
- School of Biological Sciences, University of Reading, Reading, RG6 6EX, UK.
| | - John P Wilson
- Department of Earth Sciences, Montana State University, Bozeman, MT, 59715, USA
| | - Alex Farnsworth
- School of Geographical Sciences, University of Bristol, University Road, Bristol, BS8 1RL, UK
- State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment (TPESRE), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Zackary R Perry
- University of Alaska Museum, 1962 Yukon Drive, Fairbanks, AK, 99775, USA
- Department of Geosciences, University of Alaska, Fairbanks, AK, 99775, USA
| | - Patrick S Druckenmiller
- University of Alaska Museum, 1962 Yukon Drive, Fairbanks, AK, 99775, USA
- Department of Geosciences, University of Alaska, Fairbanks, AK, 99775, USA
| | - Gregory M Erickson
- Department of Biological Science, Florida State University, Tallahassee, FL, 32306, USA
| | - Chris L Organ
- School of Biological Sciences, University of Reading, Reading, RG6 6EX, UK.
- Department of Earth Sciences, Montana State University, Bozeman, MT, 59715, USA.
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Xu X. Inferring aerial behavior in Mesozoic dinosaurs: Implications and uncertainties. Proc Natl Acad Sci U S A 2024; 121:e2401482121. [PMID: 38466860 PMCID: PMC10962949 DOI: 10.1073/pnas.2401482121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/13/2024] Open
Affiliation(s)
- Xing Xu
- Centre for Vertebrate Evolutionary Biology, School of Life Sciences, Yunnan University, Chenggong, Kunming650504, China
- Southwest United Graduate School, Kunming650092, China
- Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing100044, China
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Myhrvold NP, Baumgart SL, Vidal D, Fish FE, Henderson DM, Saitta ET, Sereno PC. Diving dinosaurs? Caveats on the use of bone compactness and pFDA for inferring lifestyle. PLoS One 2024; 19:e0298957. [PMID: 38446841 PMCID: PMC10917332 DOI: 10.1371/journal.pone.0298957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Accepted: 01/31/2024] [Indexed: 03/08/2024] Open
Abstract
The lifestyle of spinosaurid dinosaurs has been a topic of lively debate ever since the unveiling of important new skeletal parts for Spinosaurus aegyptiacus in 2014 and 2020. Disparate lifestyles for this taxon have been proposed in the literature; some have argued that it was semiaquatic to varying degrees, hunting fish from the margins of water bodies, or perhaps while wading or swimming on the surface; others suggest that it was a fully aquatic underwater pursuit predator. The various proposals are based on equally disparate lines of evidence. A recent study by Fabbri and coworkers sought to resolve this matter by applying the statistical method of phylogenetic flexible discriminant analysis to femur and rib bone diameters and a bone microanatomy metric called global bone compactness. From their statistical analyses of datasets based on a wide range of extant and extinct taxa, they concluded that two spinosaurid dinosaurs (S. aegyptiacus, Baryonyx walkeri) were fully submerged "subaqueous foragers," whereas a third spinosaurid (Suchomimus tenerensis) remained a terrestrial predator. We performed a thorough reexamination of the datasets, analyses, and methodological assumptions on which those conclusions were based, which reveals substantial problems in each of these areas. In the datasets of exemplar taxa, we found unsupported categorization of taxon lifestyle, inconsistent inclusion and exclusion of taxa, and inappropriate choice of taxa and independent variables. We also explored the effects of uncontrolled sources of variation in estimates of bone compactness that arise from biological factors and measurement error. We found that the ability to draw quantitative conclusions is limited when taxa are represented by single data points with potentially large intrinsic variability. The results of our analysis of the statistical method show that it has low accuracy when applied to these datasets and that the data distributions do not meet fundamental assumptions of the method. These findings not only invalidate the conclusions of the particular analysis of Fabbri et al. but also have important implications for future quantitative uses of bone compactness and discriminant analysis in paleontology.
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Affiliation(s)
| | - Stephanie L. Baumgart
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois, United States of America
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, Florida, United States of America
| | - Daniel Vidal
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois, United States of America
- Facultad de Ciencias, Departamento de Física Matemática y de Fluidos, Grupo de Biología Evolutiva, UNED, Madrid, Madrid, Spain
| | - Frank E. Fish
- Department of Biology, West Chester University, West Chester, Pennsylvania, United States of America
| | | | - Evan T. Saitta
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois, United States of America
| | - Paul C. Sereno
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois, United States of America
- Committee on Evolutionary Biology, University of Chicago, Chicago, Illinois, United States of America
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Knoll F, Ishikawa A, Kawabe S. A proxy for brain-to-endocranial cavity index in non-neornithean dinosaurs and other extinct archosaurs. J Comp Neurol 2024; 532:e25597. [PMID: 38588163 DOI: 10.1002/cne.25597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 10/30/2023] [Accepted: 02/09/2024] [Indexed: 04/10/2024]
Abstract
Although the brain fills nearly the entire cranial cavity in birds, it can occupy a small portion of it in crocodilians. The lack of data regarding the volumetric correspondence between the brain and the cranial cavity hampers thorough assessments of the degree of encephalization in non-neornithean dinosaurs and other extinct archosaurs and, consequently, informed inferences regarding their cognitive capacities. Existing data suggest that, across extant archosaurs, the degree of endocranial doming and the volume of intracranial nonneural components are inversely related. We build upon this information to develop an equation relating these two anatomical features in non-neornithean dinosaurs and other extinct archosaurs. We rely on measurements of the endocast doming and brain-to-endocranial cavity (BEC) index in extant relatives of non-neornithean dinosaurs, namely, the crurotarsans Caiman crocodilus, Crocodylus niloticus, and Crocodylus porosus; the paleognaths Struthio camelus and Apteryx mantelli; and the fowl Macrocephalon maleo, Gallus gallus, Meleagris gallopavo, Phasianus colchicus, and Anas platyrhynchos. Applying the equation to representative endocasts from major clades of dinosaurs, we found that BEC varies from about 0.6 in ceratopsians and thyreophorans to around 0.7 in ornithopods, pachycephalosaurians, sauropods, and theropods. We, therefore, warn against the use of a catch-all value, like 0.5, and instead encourage refinement in the adoption of BEC across archosaurs.
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Affiliation(s)
- Fabien Knoll
- Departamento de Paleobiología, Museo Nacional de Ciencias Naturales-CSIC, Madrid, Spain
| | - Asato Ishikawa
- Department of Bioscience and Biotechnology, Fukui Prefectural University, Eiheiji, Japan
| | - Soichiro Kawabe
- Institute of Dinosaur Research, Fukui Prefectural University, Eiheiji, Japan
- Fukui Prefectural Dinosaur Museum, Katsuyama, Japan
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8
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Motani R, Pyenson ND. Downsizing a heavyweight: factors and methods that revise weight estimates of the giant fossil whale Perucetus colossus. PeerJ 2024; 12:e16978. [PMID: 38436015 PMCID: PMC10909350 DOI: 10.7717/peerj.16978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 01/29/2024] [Indexed: 03/05/2024] Open
Abstract
Extremes in organismal size have broad interest in ecology and evolution because organismal size dictates many traits of an organism's biology. There is particular fascination with identifying upper size extremes in the largest vertebrates, given the challenges and difficulties of measuring extant and extinct candidates for the largest animal of all time, such as whales, terrestrial non-avian dinosaurs, and extinct marine reptiles. The discovery of Perucetus colossus, a giant basilosaurid whale from the Eocene of Peru, challenged many assumptions about organismal extremes based on reconstructions of its body weight that exceeded reported values for blue whales (Balaenoptera musculus). Here we present an examination of a series of factors and methodological approaches to assess reconstructing body weight in Perucetus, including: data sources from large extant cetaceans; fitting published body mass estimates to body outlines; testing the assumption of isometry between skeletal and body masses, even with extrapolation; examining the role of pachyostosis in body mass reconstructions; addressing method-dependent error rates; and comparing Perucetus with known physiological and ecological limits for living whales, and Eocene oceanic productivity. We conclude that Perucetus did not exceed the body mass of today's blue whales. Depending on assumptions and methods, we estimate that Perucetus weighed 60-70 tons assuming a length 17 m. We calculated larger estimates potentially as much as 98-114 tons at 20 m in length, which is far less than the direct records of blue whale weights, or the 270 ton estimates that we calculated for body weights of the largest blue whales measured by length.
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Affiliation(s)
- Ryosuke Motani
- Department of Earth and Planetary Sciences, University of California, Davis, Davis, California, United States
| | - Nicholas D. Pyenson
- Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, District of Columbia, United States
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Wu Q, O’Connor JK, Wang S, Zhou Z. Transformation of the pectoral girdle in pennaraptorans: critical steps in the formation of the modern avian shoulder joint. PeerJ 2024; 12:e16960. [PMID: 38436017 PMCID: PMC10909347 DOI: 10.7717/peerj.16960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 01/26/2024] [Indexed: 03/05/2024] Open
Abstract
Important transformations of the pectoral girdle are related to the appearance of flight capabilities in the Dinosauria. Previous studies on this topic focused mainly on paravians yet recent data suggests flight evolved in dinosaurs several times, including at least once among non-avialan paravians. Thus, to fully explore the evolution of flight-related avian shoulder girdle characteristics, it is necessary to compare morphology more broadly. Here, we present information from pennaraptoran specimens preserving pectoral girdle elements, including all purportedly volant taxa, and extensively compare aspects of the shoulder joint. The results show that many pectoral girdle modifications appear during the evolution from basal pennaraptorans to paravians, including changes in the orientation of the coracoid body and the location of the articulation between the furcula and scapula. These modifications suggest a change in forelimb range of motion preceded the origin of flight in paravians. During the evolution of early avialans, additional flight adaptive transformations occur, such as the separation of the scapula and coracoid and reduction of the articular surface between these two bones, reduction in the angle between these two elements, and elongation of the coracoid. The diversity of coracoid morphologies and types of articulations joining the scapula-coracoid suggest that each early avialan lineage evolved these features in parallel as they independently evolved more refined flight capabilities. In early ornithothoracines, the orientation of the glenoid fossa and location of the acrocoracoid approaches the condition in extant birds, suggesting a greater range of motion in the flight stroke, which may represent the acquisition of improved powered flight capabilities, such as ground take-off. The formation of a new articulation between the coracoid and furcula in the Ornithuromorpha is the last step in the formation of an osseous triosseal canal, which may indicate the complete acquisition of the modern flight apparatus. These morphological transitions equipped birds with a greater range of motion, increased and more efficient muscular output and while at the same time transmitting the increased pressure being generated by ever more powerful flapping movements in such a way as to protect the organs. The driving factors and functional adaptations of many of these transitional morphologies are as yet unclear although ontogenetic transitions in forelimb function observed in extant birds provide an excellent framework through which we can explore the behavior of Mesozoic pennaraptorans.
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Affiliation(s)
- Qian Wu
- University of Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Life and Paleoenvironment, Beijing, China
- Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China
| | - Jingmai K. O’Connor
- Negaunee Integrative Research Center, Field Museum of Natural History, Chicago, IL, United States of America
| | - Shiying Wang
- College of Paleontology, Shenyang Normal University, Shenyang, China
| | - Zhonghe Zhou
- CAS Center for Excellence in Life and Paleoenvironment, Beijing, China
- Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China
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Wildner M. Die Dinosaurier und das Weltklima. Gesundheitswesen 2024; 86:99-102. [PMID: 38378012 PMCID: PMC10883000 DOI: 10.1055/a-2220-7799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2024]
Abstract
Der Einschlag des im Durchmesser 14 km messenden Asteroiden vor 66 Millionen Jahren
auf unserem Planeten kam urplötzlich – und hatte gravierende Folgen
1. Geologisch hinterließ er im
Durchmesser den 180 km messenden Chicxulub-Krater auf der mexikanischen Halbinsel
Yukatan, biologisch war er der Anfang vom Ende der Dinosaurier. Von diesen
„schrecklichen Echsen“ (griechisch: „deinos sauros“)
stammen die beindruckend großen Fossilien, welche heute in Naturkundemuseen
weltweit zu bestaunen sind. Das mit diesem Ereignis verbundene Sterben von drei
Vierteln aller Arten – nicht nur bei den Sauriern – als Folge eines
globalen Winters und einer anschließenden anhaltenden Abkühlung
erstreckte sich vermutlich über Tausende von Jahren. Es markierte den
Übergang von der Kreidezeit in ein neues Erdzeitalter, welches insbesondere
den Säugetieren neue ökologische Nischen zur weiteren erfolgreichen
Entfaltung bot. Es war das fünfte massenhafte Artensterben innerhalb der
letzten 500 Millionen Jahre gewesen. Deren Auslöser waren neben dem
beschriebenen Asteroideneinschlag (Ereignis fünf) eine rasche alternierende
Abfolge von Kalt- und Warmzeiten (Ereignis eins), eine globale Kaltzeit infolge der
Besiedlung des Landes durch Pflanzen (Ereignis zwei), intensive vulkanische
Aktivitäten mit Übersäuerung durch Kohlendioxid und
Schwefelwasserstoffe zu Lande und zu Wasser (Ereignis drei) sowie tiefseeische
Vulkanausbrüche mit globaler Erwärmung und chemischen
Veränderungen in den Ozeanen (Ereignis vier) 2.
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Atkins-Weltman KL, Simon DJ, Woodward HN, Funston GF, Snively E. A new oviraptorosaur (Dinosauria: Theropoda) from the end-Maastrichtian Hell Creek Formation of North America. PLoS One 2024; 19:e0294901. [PMID: 38266012 PMCID: PMC10807829 DOI: 10.1371/journal.pone.0294901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 11/08/2023] [Indexed: 01/26/2024] Open
Abstract
Caenagnathidae is a clade of derived, Late Cretaceous oviraptorosaurian theropods from Asia and North America. Because their remains are rare and often fragmentary, caenagnathid diversity is poorly understood. Anzu wyliei is the only caenagnathid species currently described from the late Maastrichtian Hell Creek Formation of the USA and is also among the largest and most completely preserved North American caenagnathids. Smaller, less complete caenagnathid material has long been known from the Hell Creek Formation, but it is unclear whether these are juvenile representatives of Anzu or if they represent distinct, unnamed taxa. Here, we describe a relatively small caenagnathid hindlimb from the Hell Creek Formation, and conduct osteohistological analysis to assess its maturity. Histological data and morphological differences from Anzu wyliei and other caenagnathids allow us to conclude that this specimen represents a new species of caenagnathid from the Hell Creek Formation, with a smaller adult body size than Anzu. This new taxon is also distinct from other small caenagnathid material previously described from the area, potentially indicating the coexistence of three distinct caenagnathid species in the Hell Creek Formation. These results show that caenagnathid diversity in the Hell Creek ecosystem has been underestimated.
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Affiliation(s)
| | - D. Jade Simon
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada
| | | | | | - Eric Snively
- Oklahoma State University, Tahlequah, OK, United States of America
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Brusatte SL. Sexual selection and the evolution of dinosaur flight. Proc Natl Acad Sci U S A 2024; 121:e2320846121. [PMID: 38190533 PMCID: PMC10801913 DOI: 10.1073/pnas.2320846121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2024] Open
Affiliation(s)
- Stephen L. Brusatte
- School of GeoSciences, University of Edinburgh, EdinburghEH9 3FE, United Kingdom
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13
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Howell MM, Gee CT, Böttger C, Südekum KH. Digestibility of dinosaur food plants revisited and expanded: Previous data, new taxa, microbe donors, foliage maturity, and seasonality. PLoS One 2023; 18:e0291058. [PMID: 38100456 PMCID: PMC10723699 DOI: 10.1371/journal.pone.0291058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 08/21/2023] [Indexed: 12/17/2023] Open
Abstract
Although the living relatives of the Mesozoic flora were once assumed to constitute a nutritionally poor diet for dinosaur herbivores, in vitro fermentation of their foliage has shown that gymnosperms, ferns, and fern relatives can be as highly digestible as angiosperm grasses and dicots. Because nutritional information cannot be preserved in the fossil record, this laboratory approach, first published in 2008, provides a novel alternative to evaluate the digestive quality of the plants that were available to dinosaur megaherbivores such as sauropods. However, very few further studies have since been conducted to supplement and confirm the high fermentative capacity of nonangiospermous taxa. Here we show that the living relatives of the Araucariaceae and Equistaceae are consistently highly digestible, even between taxa and when influenced by environmental and biological factors, while fern taxa are inconsistent on the family level. These results reinforce previous findings about the high energetic potential of Jurassic-age plant families. Fourteen species of fern and gymnosperm foliage from five Jurassic families were collected in the spring and fall, then analyzed for their digestibility using the in vitro Hohenheim gas test. Equisetum, Araucaria, and Angiopteris were the most digestible genera in both seasons, while Agathis, Wollemia, and Marattia were the least digestible. The season in which specimens were collected was found to have to a significant effect on gas production in four out of 16 samples (P < 0.05). Furthermore, leaf maturity influences digestibility in Marattia attenuata (P < 0.05), yet not in Cyathea cooperi (P = 0.24). Finally, the species of the rumen fluid donor did not influence digestibility (P = 0.74). With the original data set supplemented by one new genus and four species, this study confirms and expands previous results about the nutritional capacity of the living relatives of the Jurassic flora.
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Affiliation(s)
- Mariah M. Howell
- Division of Paleontology, Institute of Geosciences, University of Bonn, Bonn, Germany
| | - Carole T. Gee
- Division of Paleontology, Institute of Geosciences, University of Bonn, Bonn, Germany
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Price M. Dinosaur extinction researcher guilty of research misconduct. Science 2023; 382:1225. [PMID: 38096302 DOI: 10.1126/science.adn4967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2023]
Abstract
But Robert DePalma did not commit fraud in paper claiming asteroid hit in springtime, university report finds.
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15
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Senter PJ. Restudy of shoulder motion in the theropod dinosaur Mononykus olecranus (Alvarezsauridae). PeerJ 2023; 11:e16605. [PMID: 38077415 PMCID: PMC10704983 DOI: 10.7717/peerj.16605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 11/15/2023] [Indexed: 12/18/2023] Open
Abstract
Background Range of motion in the forelimb of the Upper Cretaceous theropod dinosaur Mononykus olecranus, a member of the family Alvarezsauridae, has previously been investigated. However, the method used to investigate range of motion at the shoulder in M. olecranus did not follow the standardized procedure used in subsequent studies. The latter procedure yields more reliable results, and its standardization provides that its results are directly comparable to the results of similar studies in other species. I therefore reinvestigated the range of motion at the shoulder in M. olecranus, using the latter procedure. Methods Casts of the left scapula and coracoid of M. olecranus were posed on a horizontal surface, supported from beneath with modeling clay, with the medial surface of the scapula facing toward the horizontal surface. A cast of the left humerus was posed at the limits of motion through the transverse and parasagittal planes. Photos of the poses in orthal views were superimposed and used to measure range of motion, which was measured as the angle between lines drawn down the long axis of the humerus in each position. Results Through the transverse plane, the humerus of M. olecranus could be elevated to a subhorizontal position and depressed to a subvertical position. It could move through the parasagittal plane from a subvertical position at full protraction to a position above the horizontal at full retraction. These results correct the previous mischaracterization of shoulder motion in M. olecranus as restricted to a small arc with the arms held in a permanent sprawl. The range of humeral motion in M. olecranus is much greater than that found by the previous method and allowed the animal to tuck its arms in at the sides, in addition to allowing them to sprawl so as to orient the palm downward. The wide range of humeral motion allowed M. olecranus to forage for insects by employing hook-and-pull digging at surfaces with a wider range of orientations than the previous study showed to be possible.
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Affiliation(s)
- Philip J. Senter
- Department of Biological and Forensic Sciences, Fayetteville State University, Fayetteville, North Carolina, United States
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16
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Urban CA, Legendre LJ, Clarke JA. Description of natal down of the ostrich (Struthio camelus) and comparison with common quail (Coturnix coturnix): Developmental and evolutionary implications. J Anat 2023; 243:1007-1023. [PMID: 37515428 PMCID: PMC10641043 DOI: 10.1111/joa.13936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 06/18/2023] [Accepted: 07/13/2023] [Indexed: 07/30/2023] Open
Abstract
Natal down is a feather stage that differs in both form and function from the definitive feathers of adult birds. It has a simpler structure that has been speculated to be similar to the body coverings of non-avian dinosaurs. However, inference of the evolution of natal down has been limited by our understanding of its structural variation in extant birds. Most descriptive work has focused on neognathous birds, limiting our knowledge of the full diversity of feathers in extant taxa. Here, we describe the natal down of a post-hatch ostrich (Struthio camelus) and compare it to that of a post-hatch quail (Coturnix coturnix). We confirm the presence of featherless spaces (apteria) in S. camelus and the lack of barbules on the tips of natal down in both species. We also find differences between dorsal and ventral natal down structures, such as barbule density in S. camelus and the extent of the bare portion of the barb in both species. Surprisingly, we do not find that the neoptiles of either species follow the ideal morphologies for increasing insulation. Finally, we hypothesize that the different barb types present in S. camelus natal down result from a large addition of new barb ridges during development, which is not known except in feathers with a rachis. These results have implications for our understanding of how structure informs function and development in understudied feather types, such as those shared by non-avian dinosaurs.
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Affiliation(s)
- Carmen A Urban
- Jackson School of Geosciences, The University of Texas at Austin, Austin, Texas, USA
| | - Lucas J Legendre
- Jackson School of Geosciences, The University of Texas at Austin, Austin, Texas, USA
| | - Julia A Clarke
- Jackson School of Geosciences, The University of Texas at Austin, Austin, Texas, USA
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Ha Y, Kim SS. Classification of large ornithopod dinosaur footprints using Xception transfer learning. PLoS One 2023; 18:e0293020. [PMID: 38019896 PMCID: PMC10686485 DOI: 10.1371/journal.pone.0293020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Accepted: 10/04/2023] [Indexed: 12/01/2023] Open
Abstract
Large ornithopod dinosaur footprints have been confirmed on all continents except Antarctica since the 19th century. However, oversplitting problems in ichnotaxa have historically been observed in these footprints. To address these issues and distinguish between validated ichnotaxa, this study employed convolutional neural network-based Xception transfer learning to automatically classify ornithopod dinosaur tracks. The machine learning model was trained for 162 epochs (i.e., the number of full cycles of all training data through the model) using 274 data images, excluding horizontally flipped images. The trained model accuracy was 96.36%, and the validation accuracy was 92.59%. We demonstrate the performance of the machine learning model using footprint illustrations that are not included in the training dataset. These results show that the machine learning model developed in this study can properly classify footprint illustration data for large ornithopod dinosaurs. However, the quality of footprint illustration data (or images) inherently affects the performance of our machine learning model, which performs better on well-preserved footprints. In addition, because the developed machine-learning model is a typical supervised learning model, it is not possible to introduce a new label or class. Although this study used illustrations rather than photos or 3D data, it is the first application of machine-learning techniques at the academic level for verifying the ichnotaxonic assignments of large ornithopod dinosaur footprints. Furthermore, the machine learning model will likely aid researchers to classify the large ornithopod dinosaur footprint ichnotaxa, thereby safeguarding against the oversplitting problem.
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Affiliation(s)
- Yeoncheol Ha
- Department of Astronomy, Space Science and Geology, Chungnam National University, Daejeon, Korea
| | - Seung-Sep Kim
- Department of Astronomy, Space Science and Geology, Chungnam National University, Daejeon, Korea
- Department of Geological Sciences, Chungnam National University, Daejeon, Korea
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18
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Baiano MA, Coria R, Chiappe LM, Zurriaguz V, Coria L. Osteology of the axial skeleton of Aucasaurus garridoi: phylogenetic and paleobiological inferences. PeerJ 2023; 11:e16236. [PMID: 38025666 PMCID: PMC10655716 DOI: 10.7717/peerj.16236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 09/14/2023] [Indexed: 12/01/2023] Open
Abstract
Aucasaurus garridoi is an abelisaurid theropod from the Anacleto Formation (lower Campanian, Upper Cretaceous) of Patagonia, Argentina. The holotype of Aucasaurus garridoi includes cranial material, axial elements, and almost complete fore- and hind limbs. Here we present a detailed description of the axial skeleton of this taxon, along with some paleobiological and phylogenetic inferences. The presacral elements are somewhat fragmentary, although these show features shared with other abelisaurids. The caudal series, to date the most complete among brachyrostran abelisaurids, shows several autapomorphic features including the presence of pneumatic recesses on the dorsal surface of the anterior caudal neural arches, a tubercle lateral to the prezygapophysis of mid caudal vertebrae, a marked protuberance on the lateral rim of the transverse process of the caudal vertebrae, and the presence of a small ligamentous scar near the anterior edge of the dorsal surface in the anteriormost caudal transverse process. The detailed study of the axial skeleton of Aucasaurus garridoi has also allowed us to identify characters that could be useful for future studies attempting to resolve the internal phylogenetic relationships of Abelisauridae. Computed tomography scans of some caudal vertebrae show pneumatic traits in neural arches and centra, and thus the first reported case for an abelisaurid taxon. Moreover, some osteological correlates of soft tissues present in Aucasaurus and other abelisaurids, especially derived brachyrostrans, underscore a previously proposed increase in axial rigidity within Abelisauridae.
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Affiliation(s)
- Mattia Antonio Baiano
- Chinese University of Hong Kong, Hong Kong, Hong Kong
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
- Museo Municipal Ernesto Bachmann, Villa el Chocón, Argentina
- Universidad Nacional de Río Negro, General Roca, Argentina
| | - Rodolfo Coria
- Universidad Nacional de Río Negro, General Roca, Argentina
- Museo Municipal Carmen Funes, Plaza Huincul, Argentina
| | - Luis M. Chiappe
- Dinosaur Institute, Natural History Museum of Los Angeles County, Los Angeles, United States of America
| | - Virginia Zurriaguz
- Instituto de Investigación en Paleobiología y Geología (IIPG), General Roca, Argentina
| | - Ludmila Coria
- Museo Municipal Carmen Funes, Plaza Huincul, Argentina
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Wylie S. Tobamoviruses: Special Issue Editorial. Viruses 2023; 15:2174. [PMID: 38005852 PMCID: PMC10674936 DOI: 10.3390/v15112174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 10/26/2023] [Indexed: 11/26/2023] Open
Abstract
Tobamoviruses are plant-infecting viruses with an ancient lineage, understood to have arisen during the age of the dinosaurs in the Cretaceous period 145-66 million years ago [...].
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Affiliation(s)
- Steve Wylie
- Plant Biotechnology Research Group (Virology), Western Australian State Agricultural Biotechnology Centre, Murdoch University, Murdoch, WA 6150, Australia
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20
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Hattori S, Shibata M, Kawabe S, Imai T, Nishi H, Azuma Y. New theropod dinosaur from the Lower Cretaceous of Japan provides critical implications for the early evolution of ornithomimosaurs. Sci Rep 2023; 13:13842. [PMID: 37679444 PMCID: PMC10484975 DOI: 10.1038/s41598-023-40804-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Accepted: 08/16/2023] [Indexed: 09/09/2023] Open
Abstract
Ornithomimosauria consists of the ostrich-mimic dinosaurs, most of which showing cursorial adaptations, that often exhibit features indicative of herbivory. Recent discoveries have greatly improved our knowledge of their evolutionary history, including the divergence into Ornithomimidae and Deinocheiridae in the Early Cretaceous, but the early part of their history remains obscured because their fossil remains are scarce in the Aptian-Albian sediments. In recent years, many isolated ornithomimosaur remains have been recovered from the Aptian Kitadani Formation of Fukui, central Japan. These remains represent multiple individuals that share some morphological features common to them but unknown in other ornithomimosaurs, suggesting a monospecific accumulation of a new taxon. As a result of the description and phylogenetic analysis, the Kitadani ornithomimosaur is recovered as a new genus and species Tyrannomimus fukuiensis, the earliest definitive deinocheirid that complements our knowledge to understand the early evolutionary history of Ornithomimosauria. Due to its osteological similarity to Tyrannomimus, a taxon previously considered an early tyrannosauroid based on fragmentary specimens, namely Aviatyrannis jurassica, may represent the earliest ornithomimosaur from the Upper Jurassic of Europe, significantly expanding the temporal and biogeographic range of Ornithomimosauria. This finding fills a 20-million-year ghost lineage of Ornithomimosauria implied by the presence of the oldest fossil record of Maniraptora from the Middle Jurassic and is consistent with the hypothesis that their biogeographic range was widespread before the Pangaean breakup in the Kimmeridgian.
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Affiliation(s)
- Soki Hattori
- Institute of Dinosaur Research, Fukui Prefectural University, 4-1-1 Matsuoka-kenjojima, Eiheiji, Fukui, 910-1195, Japan.
- Fukui Prefectural Dinosaur Museum, 51-11, Terao, Muroko, Katsuyama, Fukui, 911-8601, Japan.
| | - Masateru Shibata
- Institute of Dinosaur Research, Fukui Prefectural University, 4-1-1 Matsuoka-kenjojima, Eiheiji, Fukui, 910-1195, Japan
- Fukui Prefectural Dinosaur Museum, 51-11, Terao, Muroko, Katsuyama, Fukui, 911-8601, Japan
| | - Soichiro Kawabe
- Institute of Dinosaur Research, Fukui Prefectural University, 4-1-1 Matsuoka-kenjojima, Eiheiji, Fukui, 910-1195, Japan
- Fukui Prefectural Dinosaur Museum, 51-11, Terao, Muroko, Katsuyama, Fukui, 911-8601, Japan
| | - Takuya Imai
- Institute of Dinosaur Research, Fukui Prefectural University, 4-1-1 Matsuoka-kenjojima, Eiheiji, Fukui, 910-1195, Japan
- Fukui Prefectural Dinosaur Museum, 51-11, Terao, Muroko, Katsuyama, Fukui, 911-8601, Japan
| | - Hiroshi Nishi
- Institute of Dinosaur Research, Fukui Prefectural University, 4-1-1 Matsuoka-kenjojima, Eiheiji, Fukui, 910-1195, Japan
- Fukui Prefectural Dinosaur Museum, 51-11, Terao, Muroko, Katsuyama, Fukui, 911-8601, Japan
| | - Yoichi Azuma
- Institute of Dinosaur Research, Fukui Prefectural University, 4-1-1 Matsuoka-kenjojima, Eiheiji, Fukui, 910-1195, Japan
- Fukui Prefectural Dinosaur Museum, 51-11, Terao, Muroko, Katsuyama, Fukui, 911-8601, Japan
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Thompson JB, Ramírez-Barahona S. No phylogenetic evidence for angiosperm mass extinction at the Cretaceous-Palaeogene (K-Pg) boundary. Biol Lett 2023; 19:20230314. [PMID: 37700701 PMCID: PMC10498348 DOI: 10.1098/rsbl.2023.0314] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Accepted: 08/21/2023] [Indexed: 09/14/2023] Open
Abstract
The Cretaceous-Palaeogene mass extinction event (K-Pg) witnessed upwards of 75% of animal species going extinct, most notably among these are the non-avian dinosaurs. A major question in macroevolution is whether this extinction event influenced the rise of flowering plants (angiosperms). The fossil record suggests that the K-Pg event had a strong regional impact on angiosperms with up to 75% species extinctions, but only had a minor impact on the extinction rates of major lineages (families and orders). Phylogenetic evidence for angiosperm extinction dynamics through time remains unexplored. By analysing two angiosperm mega-phylogenies containing approximately 32 000-73 000 extant species, here we show relatively constant extinction rates throughout geological time and no evidence for a mass extinction at the K-Pg boundary. Despite high species-level extinction observed in the fossil record, our results support the macroevolutionary resilience of angiosperms to the K-Pg mass extinction event via survival of higher lineages.
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Affiliation(s)
- Jamie B. Thompson
- The Milner Centre for Evolution, Department of Life Sciences, University of Bath, Bath, UK
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Affiliation(s)
- Ryosuke Motani
- Department of Earth and Planetary Sciences, University of California, Davis, Davis, California, USA
| | - David A Gold
- Department of Earth and Planetary Sciences, University of California, Davis, Davis, California, USA
| | - Sandra J Carlson
- Department of Earth and Planetary Sciences, University of California, Davis, Davis, California, USA
| | - Geerat J Vermeij
- Department of Earth and Planetary Sciences, University of California, Davis, Davis, California, USA.
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Liu QL, Cheng L, Stubbs TL, Moon BC, Benton MJ, Yan CB, Tian L. Rapid neck elongation in Sauropterygia (Reptilia: Diapsida) revealed by a new basal pachypleurosaur from the Lower Triassic of China. BMC Ecol Evol 2023; 23:44. [PMID: 37648992 PMCID: PMC10469986 DOI: 10.1186/s12862-023-02150-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 08/16/2023] [Indexed: 09/01/2023] Open
Abstract
Neck elongation has appeared independently in several tetrapod groups, including giraffes and sauropod dinosaurs on land, birds and pterosaurs in the air, and sauropterygians (plesiosaurs and relatives) in the oceans. Long necks arose in Early Triassic sauropterygians, but the nature and rate of that elongation has not been documented. Here, we report a new species of pachypleurosaurid sauropterygian, Chusaurus xiangensis gen. et sp. nov., based on two new specimens from the Early Triassic Nanzhang-Yuan'an Fauna in the South China Block. The new species shows key features of its Middle Triassic relatives, but has a relatively short neck, measuring 0.48 of the trunk length, compared to > 0.8 from the Middle Triassic onwards. Comparative phylogenetic analysis shows that neck elongation occurred rapidly in all Triassic eosauropterygian lineages, probably driven by feeding pressure in a time of rapid re-establishment of new kinds of marine ecosystems.
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Affiliation(s)
- Qi-Ling Liu
- Hubei Key Laboratory of Paleontology and Geological Environment Evolution, Wuhan Centre of China Geological Survey, Wuhan, 430023, P. R. China
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, Hubei, 430078, P. R. China
| | - Long Cheng
- Hubei Key Laboratory of Paleontology and Geological Environment Evolution, Wuhan Centre of China Geological Survey, Wuhan, 430023, P. R. China.
| | - Thomas L Stubbs
- School of Earth Sciences, Life Sciences Building, Tyndall Avenue, University of Bristol, Bristol, BS8 1TQ, UK
- School of Life, Health and Chemical Sciences, The Open University, Milton Keynes, UK
| | - Benjamin C Moon
- School of Earth Sciences, Life Sciences Building, Tyndall Avenue, University of Bristol, Bristol, BS8 1TQ, UK
| | - Michael J Benton
- School of Earth Sciences, Life Sciences Building, Tyndall Avenue, University of Bristol, Bristol, BS8 1TQ, UK
| | - Chun-Bo Yan
- Hubei Key Laboratory of Paleontology and Geological Environment Evolution, Wuhan Centre of China Geological Survey, Wuhan, 430023, P. R. China
| | - Li Tian
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, Hubei, 430078, P. R. China.
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Mainwaring MC, Medina I, Tobalske BW, Hartley IR, Varricchio DJ, Hauber ME. The evolution of nest site use and nest architecture in modern birds and their ancestors. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220143. [PMID: 37427466 PMCID: PMC10331912 DOI: 10.1098/rstb.2022.0143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 05/19/2023] [Indexed: 07/11/2023] Open
Abstract
The evolution of nest site use and nest architecture in the non-avian ancestors of birds remains poorly understood because nest structures do not preserve well as fossils. Nevertheless, the evidence suggests that the earliest dinosaurs probably buried eggs below ground and covered them with soil so that heat from the substrate fuelled embryo development, while some later dinosaurs laid partially exposed clutches where adults incubated them and protected them from predators and parasites. The nests of euornithine birds-the precursors to modern birds-were probably partially open and the neornithine birds-or modern birds-were probably the first to build fully exposed nests. The shift towards smaller, open cup nests has been accompanied by shifts in reproductive traits, with female birds having one functioning ovary in contrast to the two ovaries of crocodilians and many non-avian dinosaurs. The evolutionary trend among extant birds and their ancestors has been toward the evolution of greater cognitive abilities to construct in a wider diversity of sites and providing more care for significantly fewer, increasingly altricial, offspring. The highly derived passerines reflect this pattern with many species building small, architecturally complex nests in open sites and investing significant care into altricial young. This article is part of the theme issue 'The evolutionary ecology of nests: a cross-taxon approach'.
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Affiliation(s)
| | - Iliana Medina
- School of BioSciences, University of Melbourne, Melbourne VIC 3010, Australia
| | - Bret W. Tobalske
- Field Research Station at Fort Missoula, Division of Biological Sciences, University of Montana, MT 59802, USA
| | - Ian R. Hartley
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
| | - David J. Varricchio
- Department of Earth Sciences, Montana State University, Bozeman, MT 59717, USA
| | - Mark E. Hauber
- Department of Evolution, Ecology, and Behavior, School of Integrative Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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Armitage MH. Blood Clots in Dinosaur Bones: Seemingly Permanent Organic/Mineral Interfaces in Once-living Structures. Microsc Microanal 2023; 29:1241-1242. [PMID: 37613450 DOI: 10.1093/micmic/ozad067.637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
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Brownstein CD. A late-surviving phytosaur from the northern Atlantic rift reveals climate constraints on Triassic reptile biogeography. BMC Ecol Evol 2023; 23:33. [PMID: 37460985 PMCID: PMC10351158 DOI: 10.1186/s12862-023-02136-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 06/15/2023] [Indexed: 07/20/2023] Open
Abstract
BACKGROUND The origins of all major living reptile clades, including the one leading to birds, lie in the Triassic. Following the largest mass extinction in Earth's history at the end of the Permian, the earliest definite members of the three major living reptile clades, the turtles (Testudines), crocodylians and birds (Archosauria), and lizards, snakes, amphisbaenians, and Tuatara (Lepidosauria) appeared. Recent analyses of the Triassic reptile fossil record suggest that the earliest diversifications in all three of these clades were tightly controlled by abrupt paleoclimate fluctuations and concordant environmental changes. Yet, this has only been preliminarily tested using information from evolutionary trees. Phytosauria consists of superficially crocodylian-like archosaurs that either form the sister to the crown or are the earliest divergence on the crocodylian stem and are present throughout the Triassic, making this clade an excellent test case for examining this biogeographic hypothesis. RESULTS Here, I describe a new phytosaur, Jupijkam paleofluvialis gen. et sp. nov., from the Late Triassic of Nova Scotia, Canada, which at that time sat in northern Pangaea near the northern terminus of the great central Pangean rift. As one of the northernmost occurrences of Phytosauria, J. paleofluvialis provides critical new biogeographic data that enables revised estimations of phytosaur historical biogeography along phylogenies of this clade built under multiple methodologies. Reconstructions of phytosaur historical biogeography based on different phylogenies and biogeographic models suggest that phytosaurs originated in northern Pangaea, spread southward, and then dispersed back northward at least once more during the Late Triassic. CONCLUSIONS The results presented in this study link phytosaur biogeography to major changes to Triassic global climate and aridity. Together with the earliest dinosaurs and several other reptile lineages, phytosaur diversification and migration appear to have been restricted by the formation and loss of arid belts across the Pangean supercontinent.
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Affiliation(s)
- Chase Doran Brownstein
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA.
- Stamford Museum and Nature Center, Stamford, CT, USA.
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Abstract
In the early 19th century, long before the discovery of the dinosaurs, scientists and the public alike were faced with the realization that strange beasts, wholly extinct, were once populating Earth's ancient oceans. In no small part, this realization was through the discovery of the first plesiosaurs (and ichthyosaurs) along the Dorset coast of England in the seaside town of Lyme Regis. There was this large marine reptile resembling a large sea turtle, but with four evenly shaped flippers and looking as though a large snake had been pulled through its carapace. It was soon to be named scientifically Plesiosaurus, in reference to its greater similarity to living reptiles than the Ichthyosaurus (Figure 1). While the Ichthyosaurus was relatively easily understood as a fish-shaped reptile descended from land-living ancestors, the Plesiosaurus was beyond comprehension, even though incomplete skeletons had been unearthed already in the early 18th century. Plesiosaurs seemed so alien that the first complete skeleton, discovered by the famed Mary Anning a little more than 200 years ago (Figure 1A), was considered a fake by the leading anatomist of the day, the Baron Georges Cuvier in Paris. Only study of the original specimen convinced him of the authenticity of this animal but reinforced his seminal insight that there is extinction.
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Affiliation(s)
- P Martin Sander
- Dinosaur Institute, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007, USA; Section Paleontology, Institute of Geosciences, University of Bonn, 53115 Bonn, Germany.
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Chakravarthy M. Is cardiac surgery threatening to go the dinosaur way? Ann Card Anaesth 2023; 26:119-121. [PMID: 37706373 PMCID: PMC10284475 DOI: 10.4103/aca.aca_17_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 02/15/2023] [Indexed: 09/15/2023] Open
Affiliation(s)
- Murali Chakravarthy
- Department of Anesthesia, Surgical Critical Care and Pain Relief, Fortis Hospitals, Bangalore, Karnataka, India
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31
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Price M. Paleontologist accused of fraud in paper on dino-killing asteroid. Science 2022; 378:1155-1157. [PMID: 36520907 DOI: 10.1126/science.adg2855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A former collaborator claims Robert DePalma fabricated data so he could scoop her on a high-profile study.
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Prenni AJ, Benedict KB, Day DE, Sive BC, Zhou Y, Naimie L, Gebhart KA, Dombek T, De Boskey M, Hyslop NP, Spencer E, Chew QM, Collett JL, Schichtel BA. Wintertime haze and ozone at Dinosaur National Monument. J Air Waste Manag Assoc 2022; 72:951-968. [PMID: 35254216 DOI: 10.1080/10962247.2022.2048922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 01/19/2022] [Accepted: 02/28/2022] [Indexed: 06/14/2023]
Abstract
Dinosaur National Monument (DINO) is located near the northeastern edge of the Uinta Basin and often experiences elevated levels of wintertime ground-level ozone. Previous studies have shown that high ozone mixing ratios in the Uinta Basin are driven by elevated levels of volatile organic compounds (VOCs) and nitrogen oxides (NOx) from regional oil and gas development coupled with temperature inversions and enhanced photochemistry from persistent snow cover. Here, we show that persistent snow cover and temperature inversions, along with abundant ammonia, also lead to wintertime haze in this region. A study was conducted at DINO from November 2018 through May 2020 where ozone, speciated fine and coarse aerosols, inorganic gases, and VOCs were measured. Three National Ambient Air Quality Standards (NAAQS) ozone exceedances were observed in the first winter, and no exceedances were observed in the second winter. In contrast, elevated levels of particulate matter were observed both winters, with 24-h averaged particle light extinction exceeding 100 Mm-1. These haze events were dominated by ammonium nitrate, and particulate organics were highly correlated with ammonium nitrate. Ammonium nitrate formation was limited by nitric acid in winter. As such, reductions in regional NOx emissions should reduce haze levels and improve visibility at DINO in winter. Long-term measurements of particulate matter from nearby Vernal, Utah, suggest that visibility impairment is a persistent issue in the Uinta Basin in winter. From April through October 2019, relatively clean conditions occurred, with average particle extinction of ~10 Mm-1. During this period, ammonium nitrate concentrations were lower by more than an order of magnitude, and contributions from coarse mass and soil to haze levels increased. VOC markers indicated that the high levels of observed pollutants in winter were likely from local sources related to oil and gas extraction activities.Implications: Elevated ground-level ozone and haze levels were observed at Dinosaur National Monument in winter. Haze episodes were dominated by ammonium nitrate, with 24-h averaged particle light extinction exceeding 100 Mm-1, reducing visual range near the surface to ~35 km. Despite elevated ammonium nitrate concentrations, additional gas-phase ammonia was available, such that any increase in NOx emissions in the region is likely to lead to even greater haze levels.
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Affiliation(s)
- Anthony J Prenni
- National Park Service, Air Resources Division, Lakewood, Colorado, USA
| | - Katherine B Benedict
- Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado, USA
| | - Derek E Day
- Cooperative Institute for Research in the Atmosphere (CIRA), Colorado State University, Fort Collins, Colorado, USA
| | - Barkley C Sive
- National Park Service, Air Resources Division, Lakewood, Colorado, USA
| | - Yong Zhou
- Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado, USA
| | - Lilly Naimie
- Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado, USA
| | - Kristi A Gebhart
- National Park Service, Air Resources Division, Lakewood, Colorado, USA
| | - Tracy Dombek
- Analytical Sciences, RTI International, Research Triangle Park, North Carolina, USA
| | - Miranda De Boskey
- Analytical Sciences, RTI International, Research Triangle Park, North Carolina, USA
| | - Nicole P Hyslop
- University of California, Davis, Air Quality Research Center, Davis, California, USA
| | | | | | - Jeffrey L Collett
- Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado, USA
| | - Bret A Schichtel
- National Park Service, Air Resources Division, Lakewood, Colorado, USA
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Abstract
Previous findings on dinosaur cartilage material from the Late Cretaceous of Montana suggested that cartilage is a vertebrate tissue with unique characteristics that favor nuclear preservation. Here, we analyze additional dinosaur cartilage in Caudipteryx (STM4-3) from the Early Cretaceous Jehol biota of Northeast China. The cartilage fragment is highly diagenetically altered when observed in ground-sections but shows exquisite preservation after demineralization. It reveals transparent, alumino-silicified chondrocytes and brown, ironized chondrocytes. The histochemical stain Hematoxylin and Eosin (that stains the nucleus and cytoplasm in extant cells) was applied to both the demineralized cartilage of Caudipteryx and that of a chicken. The two specimens reacted identically, and one dinosaur chondrocyte revealed a nucleus with fossilized threads of chromatin. This is the second example of fossilized chromatin threads in a vertebrate material. These data show that some of the original nuclear biochemistry is preserved in this dinosaur cartilage material and further support the hypothesis that cartilage is very prone to nuclear fossilization and a perfect candidate to further understand DNA preservation in deep time.
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Affiliation(s)
- Xiaoting Zheng
- Institute of Geology and Paleontology, Linyi University, Linyi City, Shandong, 276005, China
- Shandong Tianyu Museum of Nature, Pingyi, Shandong, 273300, China
| | - Alida M Bailleul
- Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, 142 Xizhimenwai dajie, Beijing, 100044, China.
- CAS Center for Excellence in Life and Paleoenvironment, Beijing, 100044, China.
| | - Zhiheng Li
- Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, 142 Xizhimenwai dajie, Beijing, 100044, China
- CAS Center for Excellence in Life and Paleoenvironment, Beijing, 100044, China
| | - Xiaoli Wang
- Institute of Geology and Paleontology, Linyi University, Linyi City, Shandong, 276005, China
- Shandong Tianyu Museum of Nature, Pingyi, Shandong, 273300, China
| | - Zhonghe Zhou
- Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, 142 Xizhimenwai dajie, Beijing, 100044, China
- CAS Center for Excellence in Life and Paleoenvironment, Beijing, 100044, China
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Abstract
BACKGROUND The origin of powered avian flight was a locomotor innovation that expanded the ecological potential of maniraptoran dinosaurs, leading to remarkable variation in modern birds (Neornithes). The avian sternum is the anchor for the major flight muscles and, despite varying widely in morphology, has not been extensively studied from evolutionary or functional perspectives. We quantify sternal variation across a broad phylogenetic scope of birds using 3D geometric morphometrics methods. Using this comprehensive dataset, we apply phylogenetically informed regression approaches to test hypotheses of sternum size allometry and the correlation of sternal shape with both size and locomotory capabilities, including flightlessness and the highly varying flight and swimming styles of Neornithes. RESULTS We find evidence for isometry of sternal size relative to body mass and document significant allometry of sternal shape alongside important correlations with locomotory capability, reflecting the effects of both body shape and musculoskeletal variation. Among these, we show that a large sternum with a deep or cranially projected sternal keel is necessary for powered flight in modern birds, that deeper sternal keels are correlated with slower but stronger flight, robust caudal sternal borders are associated with faster flapping styles, and that narrower sterna are associated with running abilities. Correlations between shape and locomotion are significant but show weak explanatory power, indicating that although sternal shape is broadly associated with locomotory ecology, other unexplored factors are also important. CONCLUSIONS These results display the ecological importance of the avian sternum for flight and locomotion by providing a novel understanding of sternum form and function in Neornithes. Our study lays the groundwork for estimating the locomotory abilities of paravian dinosaurs, the ancestors to Neornithes, by highlighting the importance of this critical element for avian flight, and will be useful for future work on the origin of flight along the dinosaur-bird lineage.
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Affiliation(s)
- Talia M Lowi-Merri
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, ON, M5S 3B2, Canada.
- Department of Natural History, Royal Ontario Museum, 100 Queen's Park, Toronto, ON, M5S 2C6, Canada.
| | - Roger B J Benson
- Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, OX1 3AN, UK
| | - Santiago Claramunt
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, ON, M5S 3B2, Canada
- Department of Natural History, Royal Ontario Museum, 100 Queen's Park, Toronto, ON, M5S 2C6, Canada
| | - David C Evans
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, ON, M5S 3B2, Canada
- Department of Natural History, Royal Ontario Museum, 100 Queen's Park, Toronto, ON, M5S 2C6, Canada
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Spencer MR. A new, 'hip' way to breathe. eLife 2021; 10:e70947. [PMID: 34225840 PMCID: PMC8260219 DOI: 10.7554/elife.70947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 07/01/2021] [Indexed: 11/26/2022] Open
Abstract
Ornithischians, one of the three major groups of dinosaurs, developed a unique mechanism to ensure airflow in the lungs.
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Affiliation(s)
- Marc R Spencer
- Department of Anatomy and Cell Biology, The George Washington Washington UniversityWashington, DCUnited States
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Abstract
This article discusses the chalk talk's potential as an active learning method. Although chalk talks are a form of interactive lecture, they have received little attention in the medical education literature compared with other active learning methods such as team-based learning and simulation. One of the authors (C. K. L. Phoon) has used chalk talks to teach congenital heart defects to first- and third-year NYU medical students for many years. His chalk talks have consistently earned among the highest teaching scores, and students have noted their strengths of being more interesting, clear, and tangible than didactic lectures. Using the teacher and student perspectives, we examine the chalk talk's strengths and weaknesses compared with common passive and active learning methods. Chalk talks create a real-time, shared space that facilitates the active learning goals of helping students build, test, and revise mental models (conceptual frameworks). The limited amount of information that can be presented and the ability to solicit and arrange students' ideas on the board lead to the cocreation of valuable conceptual frameworks. Chalk talks require less restructuring of teaching sessions than other active learning methods and are best suited to topics that hinge on understanding of concepts. We advocate for the chalk talk to be reexamined as a promising educational tool given its strengths and the successes that other active learning methods have shown. Furthermore, we provide guidance to help educators deliver chalk talks and discuss future studies that would advance understanding of this powerful teaching tool.
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Affiliation(s)
- Nina Singh
- Division of Pediatric Cardiology, Department of Pediatrics, Hassenfeld Children's Hospital at NYU Langone and New York University Grossman School of Medicine, New York, New York
| | - Colin K L Phoon
- Division of Pediatric Cardiology, Department of Pediatrics, Hassenfeld Children's Hospital at NYU Langone and New York University Grossman School of Medicine, New York, New York
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Cullen TM, Canale JI, Apesteguía S, Smith ND, Hu D, Makovicky PJ. Osteohistological analyses reveal diverse strategies of theropod dinosaur body-size evolution. Proc Biol Sci 2020; 287:20202258. [PMID: 33234083 PMCID: PMC7739506 DOI: 10.1098/rspb.2020.2258] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 10/22/2020] [Indexed: 08/24/2023] Open
Abstract
The independent evolution of gigantism among dinosaurs has been a topic of long-standing interest, but it remains unclear if gigantic theropods, the largest bipeds in the fossil record, all achieved massive sizes in the same manner, or through different strategies. We perform multi-element histological analyses on a phylogenetically broad dataset sampled from eight theropod families, with a focus on gigantic tyrannosaurids and carcharodontosaurids, to reconstruct the growth strategies of these lineages and test if particular bones consistently preserve the most complete growth record. We find that in skeletally mature gigantic theropods, weight-bearing bones consistently preserve extensive growth records, whereas non-weight-bearing bones are remodelled and less useful for growth reconstruction, contrary to the pattern observed in smaller theropods and some other dinosaur clades. We find a heterochronic pattern of growth fitting an acceleration model in tyrannosaurids, with allosauroid carcharodontosaurids better fitting a model of hypermorphosis. These divergent growth patterns appear phylogenetically constrained, representing extreme versions of the growth patterns present in smaller coelurosaurs and allosauroids, respectively. This provides the first evidence of a lack of strong mechanistic or physiological constraints on size evolution in the largest bipeds in the fossil record and evidence of one of the longest-living individual dinosaurs ever documented.
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Affiliation(s)
- Thomas M. Cullen
- Nauganee Integrative Research Center, Field Museum of Natural History, 1400 S Lake Shore Dr., Chicago, IL 60605, USA
- Paleontology, North Carolina Museum of Natural Sciences, 11 W. Jones St, Raleigh, NC 27601, USA
- Department of Biological Sciences, North Carolina State University, 100 Brooks Ave., Raleigh, NC 27607, USA
| | - Juan I. Canale
- CONICET, Área Laboratorio e Investigación, Museo Municipal ‘Ernesto Bachmann’, Villa El Chocón, Neuquén, Argentina
| | - Sebastián Apesteguía
- CONICET, Área de Paleontología, Fundación de Historia Natural Félix de Azara, CEBBAD, Universidad Maimónides, Hidalgo 775, 1405 Ciudad Autónoma de Buenos Aires, Argentina
| | - Nathan D. Smith
- Dinosaur Institute, Natural History Museum of Los Angeles County, 900 Exposition Blvd., Los Angeles, CA 90007, USA
| | - Dongyu Hu
- Shenyang Normal University, Paleontological Museum of Liaoning, Key Laboratory for Evolution of Past Life and Change of Past Environment, Liaoning Province and Ministry of Natural Resources, 253 North Huanghe Street, 110034 Shenyang, People's Republic of China
| | - Peter J. Makovicky
- Nauganee Integrative Research Center, Field Museum of Natural History, 1400 S Lake Shore Dr., Chicago, IL 60605, USA
- Department of Earth and Environmental Sciences, University of Minnesota, 116 Church St SE, Minneapolis, MN 55455, USA
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Ekhtiari S, Chiba K, Popovic S, Crowther R, Wohl G, Kin On Wong A, Tanke DH, Dufault DM, Geen OD, Parasu N, Crowther MA, Evans DC. First case of osteosarcoma in a dinosaur: a multimodal diagnosis. Lancet Oncol 2020; 21:1021-1022. [PMID: 32758461 DOI: 10.1016/s1470-2045(20)30171-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 03/04/2020] [Accepted: 03/09/2020] [Indexed: 11/17/2022]
Affiliation(s)
- Seper Ekhtiari
- Division of Orthopaedic Surgery, Department of Surgery, McMaster University, Hamilton, ON, Canada
| | - Kentaro Chiba
- Department of Biosphere-Geosphere Science, Okayama University of Science, Okayama, Japan
| | - Snezana Popovic
- Department of Medicine, McMaster University, Hamilton, ON, Canada
| | - Rhianne Crowther
- Department of Biology, Trent University, Peterborough, ON, Canada
| | - Gregory Wohl
- Department of Mechanical Engineering, McMaster University, Hamilton, ON, Canada
| | - Andy Kin On Wong
- Joint Department of Medical Imaging, University Health Network, Toronto, ON, Canada
| | - Darren H Tanke
- Royal Tyrrell Museum of Palaeontology, Drumheller, AB, Canada
| | | | - Olivia D Geen
- Department of Medicine, McMaster University, Hamilton, ON, Canada
| | - Naveen Parasu
- Department of Radiology, McMaster University, Hamilton, ON, Canada
| | - Mark A Crowther
- Department of Medicine, McMaster University, Hamilton, ON, Canada
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Nieuwland I. Dinosaurs in the aquarium. Public Underst Sci 2020; 29:655-663. [PMID: 32643999 DOI: 10.1177/0963662520937120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
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Crouch NMA. Extinction rates of non-avian dinosaur species are uncorrelated with the rate of evolution of phylogenetically informative characters. Biol Lett 2020; 16:20200231. [PMID: 32574533 PMCID: PMC7336841 DOI: 10.1098/rsbl.2020.0231] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 05/21/2020] [Indexed: 01/13/2023] Open
Abstract
Determining the factors that shape temporal variation in species diversity is an ongoing challenge. One theory is that species exhibiting lower rates of phenotypic evolution should be more likely to go extinct as they are more susceptible to changing environmental conditions. However, little work has been done to assess whether this process shapes comparatively few lineages, or is a common mechanism shaping changes in species diversity. Here, I analyse the correlation between rates of morphological evolution and extinction at the species level using six published morphological matrices of non-avian dinosaurs. I find no correlation between the two rates at different taxonomic scales, suggesting that extinction in these groups is better described by other factors. As there is a strong prior expectation of correlated rates, I suggest that traditional morphological matrices are inappropriate for addressing this question and that the characters governing lineage persistence are independent of those with high phylogenetic signal. This may be comprehensively determined with continued development of phenomic matrices.
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Affiliation(s)
- Nicholas M. A. Crouch
- Department of the Geophysical Sciences, The University of Chicago, 5734 South Ellis Avenue, Chicago, IL 60637, USA
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Snyder K, McLain M, Wood J, Chadwick A. Over 13,000 elements from a single bonebed help elucidate disarticulation and transport of an Edmontosaurus thanatocoenosis. PLoS One 2020; 15:e0233182. [PMID: 32437394 PMCID: PMC7241792 DOI: 10.1371/journal.pone.0233182] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 04/29/2020] [Indexed: 11/29/2022] Open
Abstract
Over twenty years of work on the Hanson Ranch (HR) Bonebed in the Lance Formation of eastern Wyoming has yielded over 13,000 individual elements primarily of the hadrosaurid dinosaur Edmontosaurus annectens. The fossil bones are found normally-graded within a fine-grained (claystone to siltstone) bed that varies from one to two meters in thickness. Almost all specimens exhibit exquisite preservation (i.e., little to no abrasion, weathering, and breakage), but they are disarticulated which, combined with our sedimentological observations, suggests that the bones were remobilized and buried after a period of initial decay and disarticulation of Edmontosaurus carcasses. Because of the large number of recovered fossil elements, we have been able to gain deeper insight into Edmontosaurus biostratigraphy including disarticulation and transport of skeletal elements. The most common postcranial elements in the bonebed are pubes, ischia, scapulae, ribs, and limb bones. By contrast, vertebrae, ilia, and chevrons are rare. The most common craniomandibular bones include dentaries, nasals, quadrates, and jugals, whereas the premaxillae, predentaries, and braincase bones are underrepresented. Thus, overall, chondrocranial and axial elements, as well as distal elements of the limbs, are distinctly underrepresented. We hypothesize that following decay and disarticulation, hydraulic winnowing removed the articulated sections (e.g., vertebral columns) and the small, distal-most elements before, or at the same time, the remaining bones were swept up in a subaqueous debris flow that generated the deposit. Comparison of the HR Bonebed with other widely dispersed Upper Cretaceous hadrosaurid-dominated bonebeds reveals many shared attributes, which suggests similar processes at work in the formation of these bonebeds across space and time. This in turn reflects similar behavior by populations of these species around the world resulting in similar modes of death, becoming interred in similar depositional settings.
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Affiliation(s)
- Keith Snyder
- Biology Department, Southern Adventist University, Collegedale, TN, United States of America
| | - Matthew McLain
- Biological and Physical Sciences, The Master’s University, Santa Clarita, CA, United States of America
| | - Jared Wood
- Department of Biological Sciences, Southwestern Adventist University, Keene, TX, United States of America
- * E-mail:
| | - Arthur Chadwick
- Department of Biological Sciences, Southwestern Adventist University, Keene, TX, United States of America
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Reisz RR, LeBlanc ARH, Maddin HC, Dudgeon TW, Scott D, Huang T, Chen J, Chen CM, Zhong S. Early Jurassic dinosaur fetal dental development and its significance for the evolution of sauropod dentition. Nat Commun 2020; 11:2240. [PMID: 32382025 PMCID: PMC7206009 DOI: 10.1038/s41467-020-16045-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 04/08/2020] [Indexed: 11/18/2022] Open
Abstract
Rare occurrences of dinosaurian embryos are punctuated by even rarer preservation of their development. Here we report on dental development in multiple embryos of the Early Jurassic Lufengosaurus from China, and compare these to patterns in a hatchling and adults. Histology and CT data show that dental formation and development occurred early in ontogeny, with several cycles of tooth development without root resorption occurring within a common crypt prior to hatching. This differs from the condition in hatchling and adult teeth of Lufengosaurus, and is reminiscent of the complex dentitions of some adult sauropods, suggesting that their derived dental systems likely evolved through paedomorphosis. Ontogenetic changes in successive generations of embryonic teeth of Lufengosaurus suggest that the pencil-like teeth in many sauropods also evolved via paedomorphosis, providing a mechanism for the convergent evolution of small, structurally simple teeth in giant diplodocoids and titanosaurids. Therefore, such developmental perturbations, more commonly associated with small vertebrates, were likely also essential events in sauropod evolution.
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Affiliation(s)
- Robert R Reisz
- Dinosaur Evolution Research Centre and International Centre of Future Science, Jilin University, Changchun, 130000, Jilin, China.
- Department of Biology, University of Toronto Mississauga, Mississauga, ON, L5L 1C6, Canada.
- National Chung Hsing University, Taichung, 40227, Taiwan.
| | - Aaron R H LeBlanc
- Department of Biological Sciences, University of Alberta, Edmonton, AB, T6G 2E9, Canada
| | - Hillary C Maddin
- Department of Earth Sciences, Carleton University, Ottawa, ON, K1S 5B6, Canada
| | - Thomas W Dudgeon
- Department of Earth Sciences, Carleton University, Ottawa, ON, K1S 5B6, Canada
| | - Diane Scott
- Department of Biology, University of Toronto Mississauga, Mississauga, ON, L5L 1C6, Canada
| | - Timothy Huang
- Dinosaur Evolution Research Centre and International Centre of Future Science, Jilin University, Changchun, 130000, Jilin, China
- National Chung Hsing University, Taichung, 40227, Taiwan
| | - Jun Chen
- Dinosaur Evolution Research Centre and International Centre of Future Science, Jilin University, Changchun, 130000, Jilin, China
| | - Chuan-Mu Chen
- National Chung Hsing University, Taichung, 40227, Taiwan
| | - Shiming Zhong
- Chuxiong Prefectural Museum, Chuxiong, 675000, Yunnan, China
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Abstract
Susceptibility to diseases is common to humans and dinosaurs. Since much of the biological history of every living creature is shaped by its diseases, recognizing them in fossilized bone can furnish us with important information on dinosaurs' physiology and anatomy, as well as on their daily activities and surrounding environment. In the present study, we examined the vertebrae of two humans from skeletal collections with Langerhans Cell Histiocytosis (LCH), a benign osteolytic tumor-like disorder involving mainly the skeleton; they were diagnosed in life, along with two hadrosaur vertebrae with an apparent lesion. Macroscopic and microscopic analyses of the hadrosaur vertebrae were compared to human LCH and to other pathologies observed via an extensive pathological survey of a human skeletal collection, as well as a three-dimensional reconstruction of the lesion and its associated blood vessels from a µCT scan. The hadrosaur pathology findings were indistinguishable from those of humans with LCH, supporting that diagnosis. This report suggests that hadrosaurids had suffered from larger variety of pathologies than previously reported. Furthermore, it seems that LCH may be independent of phylogeny.
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Affiliation(s)
- Bruce M Rothschild
- Indiana University, 2401W. University Ave., Muncie, IN, 47303, USA.
- Carnegie Museum, 4400 Forbes Ave., Pittsburgh, PA, 44272, USA.
| | - Darren Tanke
- Royal Tyrrell Museum of Palaeontology, 1500 N. Dinosaur Trail, Drumheller, AB, T0J 0Y0, Canada
| | - Frank Rühli
- Institute of Evolutionary Medicine, University of Zurich, Zurich, Switzerland
| | - Ariel Pokhojaev
- Department of Anatomy and Anthropology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- Dan David Center for Human Evolution and Biohistory Research, Shmunis Family Anthropology Institute, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Hila May
- Department of Anatomy and Anthropology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- Dan David Center for Human Evolution and Biohistory Research, Shmunis Family Anthropology Institute, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
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Vidal D, Mocho P, Páramo A, Sanz JL, Ortega F. Ontogenetic similarities between giraffe and sauropod neck osteological mobility. PLoS One 2020; 15:e0227537. [PMID: 31929581 PMCID: PMC6957182 DOI: 10.1371/journal.pone.0227537] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 12/21/2019] [Indexed: 11/19/2022] Open
Abstract
The functional morphology of sauropod dinosaur long necks has been studied extensively, with virtual approaches yielding results that are difficult to obtain with actual fossils, due to their extreme fragility and size. However, analyses on virtual fossils have been questioned on several of their premises, such as the ability to accurately reconstruct intervertebral tissue with only skeletal data; or whether zygapophyseal overlap can be used to determine the limits of range of motion, since some extreme neck poses in extant giraffes have been claimed not to retain any zygapophyseal overlap. We compared articulation and range of motion in extant giraffes with the exceptionally well-preserved and complete basally branching eusauropod Spinophorosaurus nigerensis from the Middle (?) Jurassic of Niger, under the same virtual paleontology protocols. We examined the articulation and range of motion on grown and young specimens of both Spinophorosaurus and giraffes in order to record any potential changes during ontogeny. Also, the postures of virtual giraffes were compared with previously published data from living animals in the wild. Our analyses show that: (i) articulation of virtual bones in osteologically neutral pose (ONP) does enable accurate prediction of the amount of inter-vertebral space in giraffes and, roughly, in Spinophorosaurus; (ii) even the most extreme neck postures attained by living giraffes in the wild do not require to disarticulate cervical vertebrae; (iii) both living giraffes and Spinophorosaurus have large intervertebral spaces between their cervical centra in early ontogenetical stages, which decrease as ontogeny advances; and (iv) that grown specimens have a greater osteological range of motion in living giraffes and Spinophorosaurus.
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Affiliation(s)
- Daniel Vidal
- Grupo de Biología Evolutiva, Facultad de Ciencias, UNED, Paseo Senda Del Rey, Madrid, Spain
| | - Pedro Mocho
- Grupo de Biología Evolutiva, Facultad de Ciencias, UNED, Paseo Senda Del Rey, Madrid, Spain
- Instituto Dom Luiz, Universidade de Lisboa, Bloco C6, 38 Piso, sala 6.3.57, Campo Grande, Lisbon, Portugal
- The Dinosaur Institute, Natural History Museum of Los Angeles County, Los Angeles, CA, United States of America
| | - Adrián Páramo
- Unidad de Paleontología, Facultad de Ciencias, Universidad Autónoma de Madrid, Calle Darwin, Madrid, Spain
| | - José Luis Sanz
- Unidad de Paleontología, Facultad de Ciencias, Universidad Autónoma de Madrid, Calle Darwin, Madrid, Spain
- Real Academia Española de Ciencias Exactas, Físicas y Naturales, Calle Valverde, Madrid, Spain
| | - Francisco Ortega
- Grupo de Biología Evolutiva, Facultad de Ciencias, UNED, Paseo Senda Del Rey, Madrid, Spain
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Jones ED. Assumptions of authority: the story of Sue the T-rex and controversy over access to fossils. Hist Philos Life Sci 2019; 42:2. [PMID: 31893315 DOI: 10.1007/s40656-019-0288-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 10/11/2019] [Indexed: 06/10/2023]
Abstract
Although the buying, selling, and trading of fossils has been a principle part of paleontological practice over the centuries, the commercial collection of fossils today has re-emerged into a pervasive and lucrative industry. In the United States, the number of commercial companies driving the legal, and sometimes illegal, selling of fossils is estimated to have doubled since the 1980s, and worries from academic paleontologists over this issue has increased accordingly. Indeed, some view the commercialization of fossils as one of the greatest threats to paleontology today. In this article, I address the story of "Sue"-the largest, most complete, and most expensive Tyrannosaurus rex ever excavated-whose discovery incited a series of high-profile legal battles throughout the 1990s over the question of "Who owns Sue?" Over the course of a decade, various stakeholders from academic paleontologists and fossil dealers to Native Americans, private citizens, and government officials all laid claim to Sue. In exploring this case, I argue that assumptions of authority are responsible for initiating and sustaining debates over fossil access. Here, assumptions of authority are understood as assumptions of ownership, or expertise, or in some cases both. Viewing the story from this perspective illuminates the significance of fossils as boundary objects. It also highlights the process of boundary-work by which individuals and groups constructed or deconstructed borders around Sue (specifically) and fossil access (more generally) to establish their own authority. I draw on science studies scholarship as well as literature in the professionalization, commercialization, and valuation of science to examine how assumptions of authority facilitated one of the most divisive episodes in recent paleontological history and the broader debate on the commercial collection of vertebrate fossil material in the United Sates.
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Affiliation(s)
- Elizabeth D Jones
- Department of Forestry and Environmental Resources, North Carolina State University, 2820 Faucette Drive Campus, Box 8001, Raleigh, NC, 27606, USA.
- Department of Science and Technology Studies, University College London, 22 Gordon Square, London, WC1E 6BT, UK.
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Wang X, Tang HK, Clarke JA. Flight, symmetry and barb angle evolution in the feathers of birds and other dinosaurs. Biol Lett 2019; 15:20190622. [PMID: 31795849 PMCID: PMC6936028 DOI: 10.1098/rsbl.2019.0622] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 11/11/2019] [Indexed: 11/12/2022] Open
Abstract
There has been much discussion over whether basal birds (e.g. Archaeopteryx and Confuciusornis) exhibited active flight. A recent study of barb angles has suggested they likely could not but instead may have exhibited a gliding phase. Pennaceous primary flight feathers were proposed to show significant shifts in barb angle values of relevance to the inference of flight in these extinct taxa. However, evolutionary trends in the evolution of these barb angle traits in extant volant taxa were not analysed in a phylogenetic frame. Neither the ancestral crown avian condition nor the condition in outgroup dinosaurs with symmetrical feathers were assessed. Here, we expand the fossil sample and reanalyse these data in a phylogenetic frame. We show that extant taxa, including strong flyers (e.g. some songbirds), show convergence on trailing barb angles and barb angle asymmetry observed in Mesozoic taxa that were proposed not to be active fliers. Trailing barb angles in these Mesozoic taxa are similar to symmetrical feathers in outgroup dinosaurs, indicating that selective regimes acted to modify primarily the leading-edge barb angles. These trends inform dynamics in feather shape evolution and challenge the notion that barb angle and barb angle ratios in extant birds directly inform the reconstruction of function in extinct stem taxa.
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Affiliation(s)
- Xia Wang
- School of Biological Science and Technology, University of Jinan, Jinan 250022, People's Republic of China
| | - Ho Kwan Tang
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06511, USA
| | - Julia A. Clarke
- Department of Geological Sciences, Jackson School of Geoscience, University of Texas, Austin, TX 78712, USA
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Stocker MR, Nesbitt SJ, Kligman BT, Paluh DJ, Marsh AD, Blackburn DC, Parker WG. The earliest equatorial record of frogs from the Late Triassic of Arizona. Biol Lett 2019; 15:20180922. [PMID: 30958136 PMCID: PMC6405462 DOI: 10.1098/rsbl.2018.0922] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Accepted: 02/01/2019] [Indexed: 12/26/2022] Open
Abstract
Crown-group frogs (Anura) originated over 200 Ma according to molecular phylogenetic analyses, though only a few fossils from high latitudes chronicle the first approximately 60 Myr of frog evolution and distribution. We report fossils that represent both the first Late Triassic and the earliest equatorial record of Salientia, the group that includes stem and crown-frogs. These small fossils consist of complete and partial ilia with anteriorly directed, elongate and distally hollow iliac blades. These features of these ilia, including the lack of a prominent dorsal protuberance and a shaft that is much longer than the acetabular region, suggest a closer affinity to crown-group Anura than to Early Triassic stem anurans Triadobatrachus from Madagascar and Czatkobatrachus from Poland, both high-latitude records. The new fossils demonstrate that crown anurans may have been present in the Late Triassic equatorial region of Pangea. Furthermore, the presence of Early Jurassic anurans in the same stratigraphic sequence ( Prosalirus bitis from the Kayenta Formation) suggests that anurans survived the climatic aridification of this region in the early Mesozoic. These fossils highlight the importance of the targeted collection of microfossils and provide further evidence for the presence of crown-group representatives of terrestrial vertebrates prior to the end-Triassic extinction.
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Affiliation(s)
| | | | - Ben T. Kligman
- Department of Geosciences, Virginia Tech, Blacksburg, VA 24061, USA
- Petrified Forest National Park, 1 Park Road, Petrified Forest, AZ 86028, USA
| | - Daniel J. Paluh
- Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA
| | - Adam D. Marsh
- Petrified Forest National Park, 1 Park Road, Petrified Forest, AZ 86028, USA
| | - David C. Blackburn
- Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA
| | - William G. Parker
- Petrified Forest National Park, 1 Park Road, Petrified Forest, AZ 86028, USA
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Pan Y, Zheng W, Sawyer RH, Pennington MW, Zheng X, Wang X, Wang M, Hu L, O'Connor J, Zhao T, Li Z, Schroeter ER, Wu F, Xu X, Zhou Z, Schweitzer MH. The molecular evolution of feathers with direct evidence from fossils. Proc Natl Acad Sci U S A 2019; 116:3018-3023. [PMID: 30692253 PMCID: PMC6386655 DOI: 10.1073/pnas.1815703116] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Dinosaur fossils possessing integumentary appendages of various morphologies, interpreted as feathers, have greatly enhanced our understanding of the evolutionary link between birds and dinosaurs, as well as the origins of feathers and avian flight. In extant birds, the unique expression and amino acid composition of proteins in mature feathers have been shown to determine their biomechanical properties, such as hardness, resilience, and plasticity. Here, we provide molecular and ultrastructural evidence that the pennaceous feathers of the Jurassic nonavian dinosaur Anchiornis were composed of both feather β-keratins and α-keratins. This is significant, because mature feathers in extant birds are dominated by β-keratins, particularly in the barbs and barbules forming the vane. We confirm here that feathers were modified at both molecular and morphological levels to obtain the biomechanical properties for flight during the dinosaur-bird transition, and we show that the patterns and timing of adaptive change at the molecular level can be directly addressed in exceptionally preserved fossils in deep time.
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Affiliation(s)
- Yanhong Pan
- Chinese Academy of Sciences Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, Nanjing 210008, China;
| | - Wenxia Zheng
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695
| | - Roger H Sawyer
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29205
| | | | - Xiaoting Zheng
- Institute of Geology and Paleontology, Lingyi University, Lingyi City, 27605 Shandong, China
- Shandong Tianyu Museum of Nature, Pingyi, 273300 Shandong, China
| | - Xiaoli Wang
- Institute of Geology and Paleontology, Lingyi University, Lingyi City, 27605 Shandong, China
- Shandong Tianyu Museum of Nature, Pingyi, 273300 Shandong, China
| | - Min Wang
- CAS Key Laboratory of Vertebrate Evolution and Human Origins of the Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, 100044 Beijing, China
- Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, 100044 Beijing, China
| | - Liang Hu
- Chinese Academy of Sciences Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, Nanjing 210008, China
- College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, 100049 Beijing, China
| | - Jingmai O'Connor
- CAS Key Laboratory of Vertebrate Evolution and Human Origins of the Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, 100044 Beijing, China
- Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, 100044 Beijing, China
| | - Tao Zhao
- Chinese Academy of Sciences Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, Nanjing 210008, China
| | - Zhiheng Li
- CAS Key Laboratory of Vertebrate Evolution and Human Origins of the Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, 100044 Beijing, China
- Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, 100044 Beijing, China
| | - Elena R Schroeter
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695
| | - Feixiang Wu
- CAS Key Laboratory of Vertebrate Evolution and Human Origins of the Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, 100044 Beijing, China
- Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, 100044 Beijing, China
| | - Xing Xu
- CAS Key Laboratory of Vertebrate Evolution and Human Origins of the Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, 100044 Beijing, China
- Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, 100044 Beijing, China
| | - Zhonghe Zhou
- CAS Key Laboratory of Vertebrate Evolution and Human Origins of the Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, 100044 Beijing, China;
- Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, 100044 Beijing, China
- College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, 100049 Beijing, China
| | - Mary H Schweitzer
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695;
- North Carolina Museum of Natural Sciences, Raleigh, NC 27601
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49
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Vogel G. Giant mammal cousin rivaled early dinosaurs. Science 2018; 362:879. [PMID: 30467151 DOI: 10.1126/science.362.6417.879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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50
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Wiemann J, Fabbri M, Yang TR, Stein K, Sander PM, Norell MA, Briggs DEG. Fossilization transforms vertebrate hard tissue proteins into N-heterocyclic polymers. Nat Commun 2018; 9:4741. [PMID: 30413693 PMCID: PMC6226439 DOI: 10.1038/s41467-018-07013-3] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 10/10/2018] [Indexed: 02/06/2023] Open
Abstract
Vertebrate hard tissues consist of mineral crystallites within a proteinaceous scaffold that normally degrades post-mortem. Here we show, however, that decalcification of Mesozoic hard tissues preserved in oxidative settings releases brownish stained extracellular matrix, cells, blood vessels, and nerve projections. Raman Microspectroscopy shows that these fossil soft tissues are a product of diagenetic transformation to Advanced Glycoxidation and Lipoxidation End Products, a class of N-heterocyclic polymers generated via oxidative crosslinking of proteinaceous scaffolds. Hard tissues in reducing environments, in contrast, lack soft tissue preservation. Comparison of fossil soft tissues with modern and experimentally matured samples reveals how proteinaceous tissues undergo diagenesis and explains biases in their preservation in the rock record. This provides a target, focused on oxidative depositional environments, for finding cellular-to-subcellular soft tissue morphology in fossils and validates its use in phylogenetic and other evolutionary studies.
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Affiliation(s)
- Jasmina Wiemann
- Department of Geology & Geophysics, Yale University, 210 Whitney Avenue, New Haven, CT, 06511, USA.
| | - Matteo Fabbri
- Department of Geology & Geophysics, Yale University, 210 Whitney Avenue, New Haven, CT, 06511, USA
| | - Tzu-Ruei Yang
- Steinmann Institute for Geology, Mineralogy, and Paleontology, University of Bonn, Nussallee 8, 53115, Bonn, Germany
| | - Koen Stein
- Earth System Sciences AMGC, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussels, Belgium
| | - P Martin Sander
- Steinmann Institute for Geology, Mineralogy, and Paleontology, University of Bonn, Nussallee 8, 53115, Bonn, Germany
- Dinosaur Institute, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA, 90007, USA
| | - Mark A Norell
- Division of Vertebrate Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY, 10024-5192, USA
| | - Derek E G Briggs
- Department of Geology & Geophysics, Yale University, 210 Whitney Avenue, New Haven, CT, 06511, USA
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