Evolutionary Insights from an Ancient Bird
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Flying Dromaeosaurs
A winged, but flightless, Deinonychus by Stephen A. Czerkas FLYING DROMAEOSAURS Stephen A. Czerkas, Dianshuang Zhang, Jinglu Li and Yinxian Li The Dinosaur Museum, 754 South 200 West, Blanding, Utah 84511, USA; Liaoning Provincial Bureau of Land Resources Management, Liaoning Fossil Administration Office, and Liaoning Museum of Paleontology, Left of Nanshan Park, Beipiao, Liaoning Province 122100, People’s Republic of China. The Dinosaur Museum © 2002 Abstract Dromaeosaurs have been regarded as theropod dinosaurs that were among the closest avian ancestors which were strictly terrestrial having not yet evolved the ability to fly. Consequently, phylogenetic analyses have resulted in the claims of birds having evolved from “the ground up” within a dinosaurian ancestry. Though widely accepted, the relationship between birds and dinosaurs has remained highly controversial and disputed by advocates of birds as having been derived from an arboreal, non-dinosaurian type of archosaur. The cladistical interpretation of the dinosaur/bird relationship hinges upon the presumption of the dromaeosaurs inability to fly. Recent discoveries of dromaeosaurs have revealed impressions of feathers and avian characters in the skeleton that nearly equal and even surpass that of Archaeopteryx. Yet despite this, the ability to fly has been discounted due to the shorter length of the forelimbs. Described below are two such dromaeosaurs, but preserved with impressions of primary flight feathers extending from the manus which demonstrate an undeniable correlation towards the ability to fly. This compelling evidence refutes the popular interpretation of birds evolving from dinosaurs by revealing that dromaeosaurs were already birds and not the non-avian theropod dinosaurs as previously believed. -
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. -
Winter Bird Feeding
BirdNotes 1 Winter Bird Feeding birds at feeders in winter If you feed birds, you’re in good company. Birding is one of North America’s favorite pastimes. A 2006 report from the U.S. Fish and Wildlife Service estimates that about 55.5 mil- lion Americans provide food for wild birds. Chickadees Titmice Cardinals Sparrows Wood- Orioles Pigeons Nuthatches Finches Grosbeaks Blackbirds Jays peckers Tanagers Doves Sunflower ◆ ◆ ◆ ◆ ◆ ◆ ◆ Safflower ◆ ◆ ◆ Corn ◆ ◆ ◆ Millet ◆ ◆ ◆ Milo ◆ ◆ Nyjer ◆ Suet ◆ ◆ ◆ ◆ ◆ Preferred ◆ Readily Eaten Wintertime—and the Living’s counting birds at their feeders during selecting the best foods daunting. To Not Easy this winterlong survey. Great Back- attract a diversity of birds, provide a yard Bird Count participants provide variety of food types. But that doesn’t n much of North America, winter valuable data with a much shorter mean you need to purchase one of ev- Iis a difficult time for birds. Days time commitment—as little as fifteen erything on the shelf. are often windy and cold; nights are minutes in mid-February! long and even colder. Lush vegeta- Which Seed Types tion has withered or been consumed, Types of Bird Food Should I Provide? and most insects have died or become uring spring and summer, most dormant. Finding food can be espe- lack-oil sunflower seeds attract songbirds eat insects and spi- cially challenging for birds after a D Bthe greatest number of species. ders, which are highly nutritious, heavy snowfall. These seeds have a high meat-to- abundant, and for the most part, eas- shell ratio, they are nutritious and Setting up a backyard feeder makes ily captured. -
PROGRAMME ABSTRACTS AGM Papers
The Palaeontological Association 63rd Annual Meeting 15th–21st December 2019 University of Valencia, Spain PROGRAMME ABSTRACTS AGM papers Palaeontological Association 6 ANNUAL MEETING ANNUAL MEETING Palaeontological Association 1 The Palaeontological Association 63rd Annual Meeting 15th–21st December 2019 University of Valencia The programme and abstracts for the 63rd Annual Meeting of the Palaeontological Association are provided after the following information and summary of the meeting. An easy-to-navigate pocket guide to the Meeting is also available to delegates. Venue The Annual Meeting will take place in the faculties of Philosophy and Philology on the Blasco Ibañez Campus of the University of Valencia. The Symposium will take place in the Salon Actos Manuel Sanchis Guarner in the Faculty of Philology. The main meeting will take place in this and a nearby lecture theatre (Salon Actos, Faculty of Philosophy). There is a Metro stop just a few metres from the campus that connects with the centre of the city in 5-10 minutes (Line 3-Facultats). Alternatively, the campus is a 20-25 minute walk from the ‘old town’. Registration Registration will be possible before and during the Symposium at the entrance to the Salon Actos in the Faculty of Philosophy. During the main meeting the registration desk will continue to be available in the Faculty of Philosophy. Oral Presentations All speakers (apart from the symposium speakers) have been allocated 15 minutes. It is therefore expected that you prepare to speak for no more than 12 minutes to allow time for questions and switching between presenters. We have a number of parallel sessions in nearby lecture theatres so timing will be especially important. -
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. -
A Bird's Eye View of the Evolution of Avialan Flight
Chapter 12 Navigating Functional Landscapes: A Bird’s Eye View of the Evolution of Avialan Flight HANS C.E. LARSSON,1 T. ALEXANDER DECECCHI,2 MICHAEL B. HABIB3 ABSTRACT One of the major challenges in attempting to parse the ecological setting for the origin of flight in Pennaraptora is determining the minimal fluid and solid biomechanical limits of gliding and powered flight present in extant forms and how these minima can be inferred from the fossil record. This is most evident when we consider the fact that the flight apparatus in extant birds is a highly integrated system with redundancies and safety factors to permit robust performance even if one or more components of their flight system are outside their optimal range. These subsystem outliers may be due to other adaptive roles, ontogenetic trajectories, or injuries that are accommodated by a robust flight system. This means that many metrics commonly used to evaluate flight ability in extant birds are likely not going to be precise in delineating flight style, ability, and usage when applied to transitional taxa. Here we build upon existing work to create a functional landscape for flight behavior based on extant observations. The functional landscape is like an evolutionary adap- tive landscape in predicting where estimated biomechanically relevant values produce functional repertoires on the landscape. The landscape provides a quantitative evaluation of biomechanical optima, thus facilitating the testing of hypotheses for the origins of complex biomechanical func- tions. Here we develop this model to explore the functional capabilities of the earliest known avialans and their sister taxa. -
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. -
Norntates PUBLISHED by the AMERICAN MUSEUM of NATURAL HISTORY CENTRAL PARK WEST at 79TH STREET, NEW YORK, NY 10024 Number 3265, 36 Pp., 15 Figures May 4, 1999
AMERICANt MUSEUM Norntates PUBLISHED BY THE AMERICAN MUSEUM OF NATURAL HISTORY CENTRAL PARK WEST AT 79TH STREET, NEW YORK, NY 10024 Number 3265, 36 pp., 15 figures May 4, 1999 An Oviraptorid Skeleton from the Late Cretaceous of Ukhaa Tolgod, Mongolia, Preserved in an Avianlike Brooding Position Over an Oviraptorid Nest JAMES M. CLARK,I MARK A. NORELL,2 AND LUIS M. CHIAPPE3 ABSTRACT The articulated postcranial skeleton of an ovi- presence of a single, ossified ventral segment in raptorid dinosaur (Theropoda, Coelurosauria) each rib as well as ossified uncinate processes from the Late Cretaceous Djadokhta Formation associated with the thoracic ribs. Remnants of of Ukhaa Tolgod, Mongolia, is preserved over- keratinous sheaths are preserved with four of the lying a nest. The eggs are similar in size, shape, manal claws, and the bony and keratinous claws and ornamentation to another egg from this lo- were as strongly curved as the manal claws of cality in which an oviraptorid embryo is pre- Archaeopteryx and the pedal claws of modern served, suggesting that the nest is of the same climbing birds. The skeleton is positioned over species as the adult skeleton overlying it and was the center of the nest, with its limbs arranged parented by the adult. The lack of a skull pre- symmetrically on either side and its arms spread cludes specific identification, but in several fea- out around the nest perimeter. This is one of four tures the specimen is more similar to Oviraptor known oviraptorid skeletons preserved on nests than to other oviraptorids. The ventral part of the of this type of egg, comprising 23.5% of the 17 thorax is exceptionally well preserved and pro- oviraptorid skeletons collected from the Dja- vides evidence for other avian features that were dokhta Formation before 1996. -
The Fossil Remains of a Species of Hesperornis Found in Montana
290 SHUFELDT,Remains of Hesperornis. [July[ Auk THE FOSSIL REMAINS OF A SPECIES OF HESPERORNIS FOUND IN MONTANA. BY R. W. SHUFELD% M.D. Plate XI7III. ExR•,¾ in November, 1914, Mr. Charles W. Gihnore, who has chargeof the fossilbirds and reptiles in the Divisionof Palmontology of the United States National Museum, Washington, D.C., sent me a fossil vertebra, which was collected when he was associated with Dr. T. W. Stanton on an expeditionin Montana during the early autumnof 1914. This vertebra,when received by me, was labeled thus: "Coniornis altus Marsh, Lumbar vertebra, Dog Creek, I mi. above its mouth, Fergus County, Montana. CretaceousClagget formation(upper yellowish sandstone) September 26, 1914." T. W. Stanton, C. W. Gilmore. All. No." There being no proper material in the collectionsof the U.S. National Museum wherewith to comparethis vertebra, I studiedit as best I couldthrough comparing the fossilbone with the figures givenby Marsh in his Odontornithes.This comparisonconvinced me of the fact that the vertebra belongedto some medium-sized Hesperorn'is;further, that it more closelyresembled the 23d vertebra of the spinal colmnnof Hesperornisregalis than it did any other vertebra, and I was therefore led to believe that it was the correspondingvertebra of somespecies of Hcsperornis,smaller than H. regalis,probably of a speciesheretofore unclescribed. As I knew that Doctor Richard S. Lull, of the PeabodyMuseum, wasengaged upon a studyof the Hesperornithide*,at the time this bone came to me for study, I determinedto refer it to hi•n for an opinion. This 1 did with a letter datedat Washington,D.C., the 10th of November, 1914. -
Proceedings of the United States National Museum
NOTES ON THE OSTEOLOGY AND RELATIONSHIP OF THE FOSSIL BIRDS OF THE GENERA HESPERORNIS HAR- GERIA BAPTORNIS AND DIATRYMA. By Frederic A. Lucas, Acting Curator, Section of Vertebrate Fossils. Our knowledge of the few Cretaceous birds that have been discov- ered in North America is very imperfect in spite of Professor Marsh's memoir on the Odontonithes; their origin and man}^ points of their structure are still unknown and their relationship uncertain. By the kindness of Professor Williston, I am able to add a little to our knowl- edge of the structure of ITe><per<yrniH grdcUlH and Bdj^tornis advenus^ while the acquisition of a specimen of IL'sperornis regalis, by the United States National Museum, enables me to add a few details con- cerning that species. ' CRANIUM OF HESPERORNIS GRACILIS. The example of Ilesperornis gracilh belongs to the Universit}'' of Kansas, and comprises a large portion of the skeleton, including the skull. Unfortunately the neck was doubled backward, so that the skull lay against the pelvis, while portions of dorsal and sternal ribs had become crushed into and intimately associated with the cranium, so that it was impossible to make or.t the shape of the palatal bones, provided even they were present. This was particularly unfortunate, as information as to the character of the palate of the toothed birds is greatly to be desired. Theoretically, the arrangement of the bones of the palate should be somewhat reptilian, or, if the struthious ])irds are survivals, the palate of such a bird as Hesperornis should present some droma^ognathous characters. -
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.