Anatomy of Parahesperornis: Evolutionary Mosaicism in the Cretaceous Hesperornithiformes (Aves) DOI Creative Commons

Alyssa Bell,

Luis M. Chiappe

Life, Journal Year: 2020, Volume and Issue: 10(5), P. 62 - 62

Published: May 14, 2020

The Hesperornithiformes constitute the first known avian lineage to secondarily lose flight in exchange for evolution of a highly derived foot-propelled diving lifestyle, thus representing truly aquatic birds. First unearthed 19th century, and today from numerous Late Cretaceous (Cenomanian-Maastrichtian) sites distributed across northern hemisphere, these toothed birds have become icons early evolution. Initially erected as taxon 1984 by L. D. Martin, Parahesperornis alexi is two most complete hesperornithiform specimens discovered date has yet be fully described. P. contributes significantly our understanding birds, despite often being neglected favor iconic Hesperornis. Here, we present full anatomical description based upon nearly collections University Kansas Natural History Museum, well an extensive comparison other taxa. This study reveals possess mosaic basal traits found among taxa, indicating transitional form describes broad evolutionary patterns within Hesperornithiformes, highlighting significance not only incredible example ecological specializations, but also modern bird evolution, they are last divergence pre-modern diversification.

Language: Английский

Pennaraptoran Theropod Dinosaurs Past Progress and New Frontiers DOI
Michael Pittman, Xing Xu

Bulletin of the American Museum of Natural History, Journal Year: 2020, Volume and Issue: 440(1), P. 1 - 1

Published: Aug. 21, 2020

Language: Английский

Citations

71
Re-evaluation of the Bahariya Formation carcharodontosaurid (Dinosauria: Theropoda) and its implications for allosauroid phylogeny DOI Creative Commons
Maximilian Kellermann, Elena Cuesta, Oliver W. M. Rauhut

et al.

PLoS ONE, Journal Year: 2025, Volume and Issue: 20(1), P. e0311096 - e0311096

Published: Jan. 14, 2025

The first partial skeleton of a carcharodontosaurid theropod was described from the Egyptian Bahariya Oasis by Ernst Stromer in 1931. referred specimen to species Megalosaurus saharicus , originally on basis isolated teeth slightly older rocks Algeria, under new genus name Carcharodontosaurus . Unfortunately, almost all material Oasis, including destroyed during World War II. In 1996, relatively complete cranium similar aged Morocco and designated neotype 2007. However, due destruction original material, comparisons fossils have so far only been done cursorily. A detailed reexamination available information carcharodontosaurid, previously undescribed photograph exhibited specimen, reveals that it differs Moroccan numerous characters, such as development emargination antorbital fossa nasals, presence horn-like rugosity nasal, lack dorsoventral expansion lacrimal contact frontals, relative enlargement cerebrum. referability Algerian M is found be questionable, designation for C accepted here consideration ICZN Atricle 75, both compares more favorably originates locality closer type locality. species, Tameryraptor markgrafi gen. et sp. nov, proposed taxon. theropods Kem Group are thus not closely related thought, faunal similarities between these two strata need further examination.

Language: Английский

Citations

1
Whence the birds: 200 years of dinosaurs, avian antecedents DOI Creative Commons
Daniel J. Field, Maria Grace Burton, Juan Benito

et al.

Biology Letters, Journal Year: 2025, Volume and Issue: 21(1)

Published: Jan. 1, 2025

Among the most revolutionary insights emerging from 200 years of research on dinosaurs is that clade Dinosauria represented by approximately 11 000 living species birds. Although origin birds among has been reviewed extensively, recent have witnessed tremendous progress in our understanding deep evolutionary origins numerous distinctive avian anatomical systems. These advances enabled exciting new fossil discoveries, leading to an ever-expanding phylogenetic framework with which pinpoint characteristic features. The present review focuses four notable systems whose Mesozoic history greatly clarified discoveries: brain, kinetic palate, pectoral girdle and postcranial skeletal pneumaticity.

Language: Английский

Citations

1
Earliest short-tailed bird from the Late Jurassic of China DOI
Runsheng Chen, Min Wang, Liping Dong

et al.

Nature, Journal Year: 2025, Volume and Issue: 638(8050), P. 441 - 448

Published: Feb. 12, 2025

Language: Английский

Citations

1
The trophic habits of early birds DOI
Jingmai K. O’Connor

Palaeogeography Palaeoclimatology Palaeoecology, Journal Year: 2018, Volume and Issue: 513, P. 178 - 195

Published: March 18, 2018

Language: Английский

Citations

81
Taxonomic identification of isolated theropod teeth: The case of the shed tooth crown associated with Aerosteon (Theropoda: Megaraptora) and the dentition of Abelisauridae DOI
Christophe Hendrickx, Emanuel Tschopp, Martín D. Ezcurra

et al.

Cretaceous Research, Journal Year: 2019, Volume and Issue: 108, P. 104312 - 104312

Published: Nov. 14, 2019

Language: Английский

Citations

63
A new paravian dinosaur from the Late Jurassic of North America supports a late acquisition of avian flight DOI Creative Commons
Scott Hartman, Mickey Mortimer,

William Wahl

et al.

PeerJ, Journal Year: 2019, Volume and Issue: 7, P. e7247 - e7247

Published: July 10, 2019

The last two decades have seen a remarkable increase in the known diversity of basal avialans and their paravian relatives. lack resolution relationships these groups combined with attributing behavior specialized taxa to base Paraves has clouded interpretations origin avialan flight. Here, we describe Hesperornithoides miessleri gen. et sp. nov., new theropod from Morrison Formation (Late Jurassic) Wyoming, USA, represented by single adult or subadult specimen comprising partial, well-preserved skull postcranial skeleton. Limb proportions firmly establish as occupying terrestrial, non-volant lifestyle. Our phylogenetic analysis emphasizes extensive taxonomic sampling robust character construction, recovering taxon most parsimoniously troodontid close Daliansaurus , Xixiasaurus Sinusonasus . Multiple alternative topologies similar degrees support, but proposals archaeopterygids, microraptorians, Rahonavis being closer Pygostylia than archaeopterygids unenlagiines are strongly rejected. All parsimonious results support hypothesis that each early clade was plesiomorphically flightless, raising possibility avian flight originated late Late Jurassic Early Cretaceous.

Language: Английский

Citations

61
A new clade of basal Early Cretaceous pygostylian birds and developmental plasticity of the avian shoulder girdle DOI Open Access
Min Wang, Thomas A. Stidham,

Zhonghe Zhou

et al.

Proceedings of the National Academy of Sciences, Journal Year: 2018, Volume and Issue: 115(42), P. 10708 - 10713

Published: Sept. 24, 2018

Early members of the clade Pygostylia (birds with a short tail ending in compound bone termed "pygostyle") are critical for understanding how modern avian bauplan evolved from long-tailed basal birds like Archaeopteryx However, currently limited known diversity early branching pygostylians obscures our this major transition evolution. Here, we describe pygostylian, Jinguofortis perplexus gen. et sp. nov., Cretaceous China that adds important information about short-tailed bird group. Phylogenetic analysis recovers (Jinguofortisidae fam. nov.) uniting and enigmatic taxon Chongmingia represents second earliest diverging group Pygostylia. Jinguofortisids preserve mosaic combination plesiomorphic nonavian theropod features such as fused scapulocoracoid (a component flight apparatus) more derived flight-related morphologies including evidence reduction manual digits among birds. The presence adult individuals independently Jinguofortisidae Confuciusornithiformes may relate to an accelerated osteogenesis during chondrogenesis likely formed through heterochronic process peramorphosis by which these taxa retain ancestors addition modifications. With wings having low aspect ratio wing loading, have been adapted particularly dense forest environments. discovery increases ecomorphological highlights importance developmental plasticity evolution

Language: Английский

Citations

47
Paravian Phylogeny and the Dinosaur-Bird Transition: An Overview DOI Creative Commons
Federico L. Agnolín, Matías J. Motta, Federico Brissón Egli

et al.

Frontiers in Earth Science, Journal Year: 2019, Volume and Issue: 6

Published: Feb. 12, 2019

Recent years witnessed the discovery of a great diversity early birds as well closely related non-avian theropods, which modified previous conceptions about origin and their flight. We here present review currently taxonomic composition main anatomical characteristics those theropod families with birds, aim to analyze discuss phylogenetic hypotheses that compete some topics dinosaur-bird transition. conclude troodontid affinities anchiornithines, dromaeosaurids microraptorians unenlagiids are dismissed in favor sister group relationships Avialae. After recodification topology TWiG scheme, results on large polytomy at base Pennaraptora. Regarding character evolution, we found that: 1) presence ossified sternum goes hand by uncinate processes; 2) folded forelimbs basal archosaurs indicates widespread distribution among reptiles, contradicting proposals forelimb folding driven propatagial associated tendons was exclusive avian lineage; 3) paravians avialans Archaeopteryx wings relatively wide, short rectricial feathers, rounded alar contour, having convex wing attack margin. These taxa exhibit restricted capabilities forelimbs, preserving hands flexor angles (respect radius/ulna) no lesser than 90º. In more derived instead, rectrices notably elongate angle described between forearm is much less 90º, indicating not only an increased capability but also variety beat movements during Because strong similarities pectoral girdle conformation ratites paravians, it possible infer were similar all these taxa, lacking complex dorsoventral excursion characteristic living neognathans.

Language: Английский

Citations

43
Birds have peramorphic skulls, too: anatomical network analyses reveal oppositional heterochronies in avian skull evolution DOI Creative Commons
Olivia Plateau, Christian Foth

Communications Biology, Journal Year: 2020, Volume and Issue: 3(1)

Published: April 24, 2020

Abstract In contrast to the vast majority of reptiles, skulls adult crown birds are characterized by a high degree integration due bone fusion, e.g., an ontogenetic event generating net reduction in number bones. To understand this process evolutionary context, we investigate postnatal changes bird and non-avian theropods using anatomical network analysis ( AnNA ). Due greater bones contacts, early juvenile have less integrated skulls, resembling their theropod ancestors, including Archaeopteryx lithographica Ichthyornis dispars . Phylogenetic comparisons indicate that skull fusion resulting modular represent peramorphosis (developmental exaggeration ancestral trait) evolved late during avialan evolution, at origin crown-birds. Succeeding general paedomorphic shape trend, occurrence additional reflects mosaic complexity avian evolution.

Language: Английский

Citations

42