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Tiny Fossil Sheds Light on Miniaturization of Birds
Retraction Tiny fossil sheds light on miniaturization of birds Roger B. J. Benson Nature 579, 199–200 (2020) In view of the fact that the authors of ‘Hummingbird-sized dinosaur from the Cretaceous period of Myanmar‘ (L. Xing et al. Nature 579, 245–249; 2020) are retracting their report, I wish to retract this News & Views article, which dealt with this study and was based on the accuracy and reproducibility of their data. Nature | 22 July 2020 ©2020 Spri nger Nature Li mited. All rights reserved. drives the assembly of DNA-PK and stimulates regulation of protein synthesis. And, although 3. Dragon, F. et al. Nature 417, 967–970 (2002). its catalytic activity in vitro, although does so further studies are required, we might have 4. Adelmant, G. et al. Mol. Cell. Proteom. 11, 411–421 (2012). much less efficiently than can DNA. taken a step closer to deciphering the 5. Britton, S., Coates, J. & Jackson, S. P. J. Cell Biol. 202, Taken together, these observations suggest mysterious ribosomopathies. 579–595 (2013). a model in which KU recruits DNA-PKcs to the 6. Barandun, J. et al. Nature Struct. Mol. Biol. 24, 944–953 (2017). small-subunit processome. In the case of Alan J. Warren is at the Cambridge Institute 7. Ma, Y. et al. Cell 108, 781–794 (2002). kinase-defective DNA-PK, the mutant enzyme’s for Medical Research, Hills Road, Cambridge 8. Yin, X. et al. Cell Res. 27, 1341–1350 (2017). inability to regulate its own activity gives the CB2 OXY, UK. 9. Sharif, H. et al. -
A New Raptorial Dinosaur with Exceptionally Long Feathering Provides Insights Into Dromaeosaurid flight Performance
ARTICLE Received 11 Apr 2014 | Accepted 11 Jun 2014 | Published 15 Jul 2014 DOI: 10.1038/ncomms5382 A new raptorial dinosaur with exceptionally long feathering provides insights into dromaeosaurid flight performance Gang Han1, Luis M. Chiappe2, Shu-An Ji1,3, Michael Habib4, Alan H. Turner5, Anusuya Chinsamy6, Xueling Liu1 & Lizhuo Han1 Microraptorines are a group of predatory dromaeosaurid theropod dinosaurs with aero- dynamic capacity. These close relatives of birds are essential for testing hypotheses explaining the origin and early evolution of avian flight. Here we describe a new ‘four-winged’ microraptorine, Changyuraptor yangi, from the Early Cretaceous Jehol Biota of China. With tail feathers that are nearly 30 cm long, roughly 30% the length of the skeleton, the new fossil possesses the longest known feathers for any non-avian dinosaur. Furthermore, it is the largest theropod with long, pennaceous feathers attached to the lower hind limbs (that is, ‘hindwings’). The lengthy feathered tail of the new fossil provides insight into the flight performance of microraptorines and how they may have maintained aerial competency at larger body sizes. We demonstrate how the low-aspect-ratio tail of the new fossil would have acted as a pitch control structure reducing descent speed and thus playing a key role in landing. 1 Paleontological Center, Bohai University, 19 Keji Road, New Shongshan District, Jinzhou, Liaoning Province 121013, China. 2 Dinosaur Institute, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, California 90007, USA. 3 Institute of Geology, Chinese Academy of Geological Sciences, 26 Baiwanzhuang Road, Beijing 100037, China. 4 University of Southern California, Health Sciences Campus, BMT 403, Mail Code 9112, Los Angeles, California 90089, USA. -
New Tyrannosaur from the Mid-Cretaceous of Uzbekistan Clarifies Evolution of Giant Body Sizes and Advanced Senses in Tyrant Dinosaurs
Edinburgh Research Explorer New tyrannosaur from the mid-Cretaceous of Uzbekistan clarifies evolution of giant body sizes and advanced senses in tyrant dinosaurs Citation for published version: Brusatte, SL, Averianov, A, Sues, H, Muir, A & Butler, IB 2016, 'New tyrannosaur from the mid-Cretaceous of Uzbekistan clarifies evolution of giant body sizes and advanced senses in tyrant dinosaurs', Proceedings of the National Academy of Sciences, pp. 201600140. https://doi.org/10.1073/pnas.1600140113 Digital Object Identifier (DOI): 10.1073/pnas.1600140113 Link: Link to publication record in Edinburgh Research Explorer Document Version: Peer reviewed version Published In: Proceedings of the National Academy of Sciences General rights Copyright for the publications made accessible via the Edinburgh Research Explorer is retained by the author(s) and / or other copyright owners and it is a condition of accessing these publications that users recognise and abide by the legal requirements associated with these rights. Take down policy The University of Edinburgh has made every reasonable effort to ensure that Edinburgh Research Explorer content complies with UK legislation. If you believe that the public display of this file breaches copyright please contact [email protected] providing details, and we will remove access to the work immediately and investigate your claim. Download date: 04. Oct. 2021 Classification: Physical Sciences: Earth, Atmospheric, and Planetary Sciences; Biological Sciences: Evolution New tyrannosaur from the mid-Cretaceous of Uzbekistan clarifies evolution of giant body sizes and advanced senses in tyrant dinosaurs Stephen L. Brusattea,1, Alexander Averianovb,c, Hans-Dieter Suesd, Amy Muir1, Ian B. Butler1 aSchool of GeoSciences, University of Edinburgh, Edinburgh EH9 3FE, UK bZoological Institute, Russian Academy of Sciences, St. -
Ghost of the Forest: the Tangible and Intangible in Natural and Cultural Heritage
Ghost of the Forest: the Tangible and Intangible in Natural and Cultural Heritage Marcel Robischon Ghost of the Forest Ghost of the Forest: the Tangible and Intangible in Natural and Cultural Heritage Marcel Robischon Junior Professor, Department of Life Sciences, Humboldt Universität zu Berlin, Germany ABSTRACT Understanding the close interconnectedness of cultural and natural, tangible and intangible heritage is central to conservation efforts. This point is illustrated by examples in which works of culture have lost their original cultural or natural context – and this includes intangible natural phenomena. Further examples are given in which biological species survived as a genetic continuum but were changed in terms of their intangibles, i.e. their behaviour, in ways that can be perceived by human observers. In this article it is argued that the addition of a fourth category of ‘intangible natural heritage’ to the existing categories of World Heritage would strengthen conservation efforts and bring forward the discussion with an integrated understanding of natural and cultural heritage. Keywords Intangible Natural Heritage, co-extinction of cultural and biological phenomena, conservation, artistic inspiration, bio- diversity, bio-cultural interaction, ephemerality, World Heritage. The interdependence and the fragility of phrased by Singer (2006), Tangible heritage is expressed tangible and intangible heritage in objects, concrete matter, enduring years and Ultimately, buildings, human-made structures and sometimes centuries, carrying with it some of the artwork would be merely near-surface biogenic substance of human life, feeling, and thought. sediments resulting from highly complex processes of bio-turbation if it were not for the cultural motivation The cultural significance of ancient tangible heritage behind their creation and the meanings attached to them. -
Dinosaur Footprints
DINOSAUR FOOTPRINTS ACTIVITY SHEET YOU WILL NEED: Measuring tape and chalk DINOSAUR BODY SIZE Playground Calculator/paper for calculations Dinosaur footprint length: measure in a straight line from the back of the foot to the tip of the longest toe. Dinosaur leg length = footprint length × 4 Dinosaur stride length: Distance between footprints Dinosaur body length = from the same foot footprint length × 10 1. Use a measuring tape, chalk and the information below to draw out your dinosaur footprints in the playground. Tip - measure the footprint length first and then draw your footprint shape. If students are working in groups, each group could choose a different footprint. Footprint length - from back Dinosaur Footprint shape of foot to tip of longest toe Stride length (cm) (cm) Allosaurus 85 340 Triceratops 90 360 Compsognathus 7.5 90 Brachiosaurus 260 1040 DINOSAUR FOOTPRINTS ACTIVITY SHEET Stride length 2. Use your measuring tape to measure the dinosaur’s stride length. Use chalk to mark where the second dinosaur footprint would go. Footprint 2 Footprint 1 3. Using the calculations on page 1 work out the leg lengths and body lengths of each dinosaur. If you have space use a measuring tape and chalk to measure out the dinosaur body lengths in the playground (some of them will be very long!). Dinosaur Footprint length (cm) Leg length (cm) Body length (cm) Allosaurus 85 Triceratops 90 Compsognathus 7.5 Brachiosaurus 260 DINOSAUR SPEED We can now work out the relative speed of the dinosaur – whether it was walking, trotting or running, by looking at its leg length and stride length. -
Re-Evaluation of the Haarlem Archaeopteryx and the Radiation of Maniraptoran Theropod Dinosaurs Christian Foth1,3 and Oliver W
Foth and Rauhut BMC Evolutionary Biology (2017) 17:236 DOI 10.1186/s12862-017-1076-y RESEARCH ARTICLE Open Access Re-evaluation of the Haarlem Archaeopteryx and the radiation of maniraptoran theropod dinosaurs Christian Foth1,3 and Oliver W. M. Rauhut2* Abstract Background: Archaeopteryx is an iconic fossil that has long been pivotal for our understanding of the origin of birds. Remains of this important taxon have only been found in the Late Jurassic lithographic limestones of Bavaria, Germany. Twelve skeletal specimens are reported so far. Archaeopteryx was long the only pre-Cretaceous paravian theropod known, but recent discoveries from the Tiaojishan Formation, China, yielded a remarkable diversity of this clade, including the possibly oldest and most basal known clade of avialan, here named Anchiornithidae. However, Archaeopteryx remains the only Jurassic paravian theropod based on diagnostic material reported outside China. Results: Re-examination of the incomplete Haarlem Archaeopteryx specimen did not find any diagnostic features of this genus. In contrast, the specimen markedly differs in proportions from other Archaeopteryx specimens and shares two distinct characters with anchiornithids. Phylogenetic analysis confirms it as the first anchiornithid recorded outside the Tiaojushan Formation of China, for which the new generic name Ostromia is proposed here. Conclusions: In combination with a biogeographic analysis of coelurosaurian theropods and palaeogeographic and stratigraphic data, our results indicate an explosive radiation of maniraptoran coelurosaurs probably in isolation in eastern Asia in the late Middle Jurassic and a rapid, at least Laurasian dispersal of the different subclades in the Late Jurassic. Small body size and, possibly, a multiple origin of flight capabilities enhanced dispersal capabilities of paravian theropods and might thus have been crucial for their evolutionary success. -
A Model Based on Curvatures of Extant Avian Ungual Bones
Inferring lifestyle for Aves and Theropoda: A model based on curvatures of extant avian ungual bones A thesis submitted to the University of Manchester for the degree of Master of Science by Research in the Faculty of Science & Engineering 2019 Savannah E. Cobb School of Earth and Environmental Sciences Contents List of Figures.........................................................................................................................4-5 List of Tables..............................................................................................................................6 List of Abbreviations..............................................................................................................7-8 Abstract......................................................................................................................................9 Declaration...............................................................................................................................10 Copyright Statement...............................................................................................................11 Acknowledgements..................................................................................................................12 1 Literature Review........................................................................................................13 1.1 Avians, avialans, and theropod dinosaurs..........................................................13 1.2 Comparative study and claws............................................................................18 -
A Fast-Growing Basal Troodontid (Dinosauria: Theropoda) from The
www.nature.com/scientificreports OPEN A fast‑growing basal troodontid (Dinosauria: Theropoda) from the latest Cretaceous of Europe Albert G. Sellés1,2*, Bernat Vila1,2, Stephen L. Brusatte3, Philip J. Currie4 & Àngel Galobart1,2 A characteristic fauna of dinosaurs and other vertebrates inhabited the end‑Cretaceous European archipelago, some of which were dwarves or had other unusual features likely related to their insular habitats. Little is known, however, about the contemporary theropod dinosaurs, as they are represented mostly by teeth or other fragmentary fossils. A new isolated theropod metatarsal II, from the latest Maastrichtian of Spain (within 200,000 years of the mass extinction) may represent a jinfengopterygine troodontid, the frst reported from Europe. Comparisons with other theropods and phylogenetic analyses reveal an autapomorphic foramen that distinguishes it from all other troodontids, supporting its identifcation as a new genus and species, Tamarro insperatus. Bone histology shows that it was an actively growing subadult when it died but may have had a growth pattern in which it grew rapidly in early ontogeny and attained a subadult size quickly. We hypothesize that it could have migrated from Asia to reach the Ibero‑Armorican island no later than Cenomanian or during the Maastrichtian dispersal events. During the latest Cretaceous (ca. 77–66 million years ago) in the run-up to the end-Cretaceous mass extinc- tion, Europe was a series of islands populated by diverse and distinctive communities of dinosaurs and other vertebrates. Many of these animals exhibited peculiar features that may have been generated by lack of space and resources in their insular habitats. -
Paravian Phylogeny and the Dinosaur-Bird Transition: an Overview
feart-06-00252 February 11, 2019 Time: 17:42 # 1 REVIEW published: 12 February 2019 doi: 10.3389/feart.2018.00252 Paravian Phylogeny and the Dinosaur-Bird Transition: An Overview Federico L. Agnolin1,2,3*, Matias J. Motta1,3, Federico Brissón Egli1,3, Gastón Lo Coco1,3 and Fernando E. Novas1,3 1 Laboratorio de Anatomía Comparada y Evolución de los Vertebrados, Museo Argentino de Ciencias Naturales Bernardino Rivadavia, Buenos Aires, Argentina, 2 Fundación de Historia Natural Félix de Azara, Universidad Maimónides, Buenos Aires, Argentina, 3 Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina Recent years witnessed the discovery of a great diversity of early birds as well as closely related non-avian theropods, which modified previous conceptions about the origin of birds and their flight. We here present a review of the taxonomic composition and main anatomical characteristics of those theropod families closely related with early birds, with the aim of analyzing and discussing the main competing hypotheses pertaining to avian origins. We reject the postulated troodontid affinities of anchiornithines, and the Edited by: dromaeosaurid affinities of microraptorians and unenlagiids, and instead place these Corwin Sullivan, University of Alberta, Canada groups as successive sister taxa to Avialae. Aiming to evaluate previous phylogenetic Reviewed by: analyses, we recoded unenlagiids in the traditional TWiG data matrix, which resulted Thomas Alexander Dececchi, in a large polytomy at the base of Pennaraptora. This indicates that the TWiG University of Pittsburgh, United States phylogenetic scheme needs a deep revision. Regarding character evolution, we found Spencer G. Lucas, New Mexico Museum of Natural that: (1) the presence of an ossified sternum goes hand in hand with that of ossified History & Science, United States uncinate processes; (2) the presence of foldable forelimbs in basal archosaurs indicates *Correspondence: widespread distribution of this trait among reptiles, contradicting previous proposals Federico L. -
Anatomy of the Early Cretaceous Enantiornithine Bird Rapaxavis Pani
Anatomy of the Early Cretaceous enantiornithine bird Rapaxavis pani JINGMAI K. O’CONNOR, LUIS M. CHIAPPE, CHUNLING GAO, and BO ZHAO O’Connor, J.K., Chiappe, L.M., Gao, C., and Zhao, B. 2011. Anatomy of the Early Cretaceous enantiornithine bird Rapaxavis pani. Acta Palaeontologica Polonica 56 (3): 463–475. The exquisitely preserved longipterygid enantiornithine Rapaxavis pani is redescribed here after more extensive prepara− tion. A complete review of its morphology is presented based on information gathered before and after preparation. Among other features, Rapaxavis pani is characterized by having an elongate rostrum (close to 60% of the skull length), rostrally restricted dentition, and schizorhinal external nares. Yet, the most puzzling feature of this bird is the presence of a pair of pectoral bones (here termed paracoracoidal ossifications) that, with the exception of the enantiornithine Concornis lacustris, are unknown within Aves. Particularly notable is the presence of a distal tarsal cap, formed by the fu− sion of distal tarsal elements, a feature that is controversial in non−ornithuromorph birds. The holotype and only known specimen of Rapaxavis pani thus reveals important information for better understanding the anatomy and phylogenetic relationships of longipterygids, in particular, as well as basal birds as a whole. Key words: Aves, Enantiornithes, Longipterygidae, Rapaxavis, Jiufotang Formation, Early Cretaceous, China. Jingmai K. O’Connor [[email protected]], Laboratory of Evolutionary Systematics of Vertebrates, Institute of Vertebrate Paleontology and Paleoanthropology, 142 Xizhimenwaidajie, Beijing, China, 100044; The Dinosaur Institute, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007 USA; Luis M. Chiappe [[email protected]], The Dinosaur Institute, Natural History Museum of Los Angeles County, 900 Ex− position Boulevard, Los Angeles, CA 90007 USA; Chunling Gao [[email protected]] and Bo Zhao [[email protected]], Dalian Natural History Museum, No. -
Cleveland Lloyd Dinosaur Quarry
of a drought or other natural disaster. Quarry visi- tors can view these fossils and explore some of the explanations that have been proposed by scientists. Allosaurus The allosaur was the most common predator during the Late Jurassic period, 155 to 145 million years ago. Allosaurs are thought to have had savvy hunting skills and it is suggested that they may have hunted in packs. One of their distinguishing charac- teristics is the presence of a small bony crest just above and forward of each massive eye. Many of the specimens from Cleveland-Lloyd dinosaur quarry are from juvenile and adolescent allosaurs. The pre- dominance of Allosaurus fragilis fossils at the quarry has given researchers an unprecedented opportunity to do an in-depth study of the species. That gives paleontologists the opportunity to study the species as a whole rather than just an individual dinosaur. The Quarry BLM’s first visitor center. It was originally dedicated Exhibits The Cleveland-Lloyd Dinosaur Quarry is home to in 1968 and was renovated and expanded in 2006. The Cleveland-Lloyd Dinosaur Quarry Na- one of the most impressive collections of dinosaur tional Natural Landmark has over 2000 square feet fossils worldwide. The quarry’s unique concentration Scientific Explanations of interactive displays and exhibits. An updated and of the meat eating Allosaurus and the enormity of One of the puzzles that have intrigued scientists colorized bone bed map shows the scattering of the deposit has fascinated both visitors and scien- is the predominance of meat eating Allosaurus (the various types of dinosaurs across the site. -
Testing the Neoflightless Hypothesis: Propatagium Reveals Flying Ancestry
J Ornithol DOI 10.1007/s10336-015-1190-9 ORIGINAL ARTICLE Testing the neoflightless hypothesis: propatagium reveals flying ancestry of oviraptorosaurs 1 2 Alan Feduccia • Stephen A. Czerkas Received: 4 September 2014 / Revised: 31 December 2014 / Accepted: 23 February 2015 Ó Dt. Ornithologen-Gesellschaft e.V. 2015 Abstract Considerable debate surrounds the numerous Zusammenfassung avian-like traits in core maniraptorans (ovirap- torosaurs, troodontids, and dromaeosaurs), especially in the Die ,,Neoflightless‘‘-Hypothese im Test: Halsflughaut Chinese Early Cretaceous oviraptorosaur Caudipteryx, (Propatagium) offenbart flugfa¨hige Vorfahren der which preserves modern avian pennaceous primary remi- Oviraptorosauria ges attached to the manus, as is the case in modern birds. Was Caudipteryx derived from earth-bound theropod di- Es gibt eine ausgiebige Debatte u¨ber die zahlreichen vo- nosaurs, which is the predominant view among palaeon- gela¨hnlichen Eigenheiten der Maniraptora (Oviraptosaurus, tologists, or was it secondarily flightless, with volant avians Troodontidae, Dromaeosaurus), vor allem des (gefiederten) or theropods as ancestors (the neoflightless hypothesis), Oviraptorosauria Caudipteryx aus der fru¨hen chinesischen which is another popular, but minority view. The discovery Kreidezeit, der genau wie rezente Vo¨gel Handschwingen here of an aerodynamic propatagium in several specimens hatte, die an den Handknochen ansetzen. Stammt Cau- provides new evidence that Caudipteryx (and hence ovi- dipteryx von den nur am Erdboden lebenden Theropoda ab - raptorosaurs) represent secondarily derived flightless die unter den Pala¨ontologen vorherrschende Meinung -, oder ground dwellers, whether of theropod or avian affinity, and war er sekunda¨r flugunfa¨hig und stammte von flugfa¨higen that their presence and radiation during the Cretaceous may Theropoden ab - die ,,Neoflightless‘‘-Hypothese, eine alter- have been a factor in the apparent scarcity of many other native, wenn auch nur von Wenigen unterstu¨tzte These.