Skull of Hesperornis and Early Evolution of Birds

  title={Skull of Hesperornis and Early Evolution of Birds},
  author={P. D. Gingerich},
Additional preparation of a specimen found a century ago permits complete reconstruction of the skull of the Cretaceous bird Hesperornis. This skull provides new evidence on the evolution of the avian palate and the origin of avian cranial kinesis, and further substantiates the evolution of birds from theropod dinosaurs. 
Braincase of Mesozoic birds: I. New preparation of the “London” Archaeopteryx
The skull is much broader and more bird-like than earlier interpreted by deBeer (1954), supporting the estimates of brain size by Jerrison (1973), and the structure of the prootic is ven-trolaterally depressed.
Cranial Anatomy and Relationships of a New Triassic Bird from Texas
The oldest known fossil bird from the Late Triassic Dockum Formation of Texas, provides insights into the anatomy, evolution and phylogenetic relationships of early birds and confirms the monophyly of the class Aves.
Paleognathous Carinate Birds from the Early Tertiary of North America
Fossils newly discovered in the Paleocene and early Eocene of western North America document some of the oldest birds known from nearly complete skeletons. These were medium-sized carinates with
A New Hesperornithid and the Relationships of the Mesozoic Birds
One of the most important avian fossils is a nearly complete skeleton of a hesperornithid from the late Cretaceous Niobrara Chalk Formation of western Kansas found by H. T. Martin in 1894, that provides the basis for a re-evaluation of the relationships of the HesperORNithiformes to other Mesozoic birds.
The origin and early diversification of birds
Numerical cladistic analysis of 73 cranial and postcranial characters has resulted in a highly corroborated hypothesis describing the phylogenetic pattern of early avian evolution. Using “non-avian
Anatomy of Parahesperornis: Evolutionary Mosaicism in the Cretaceous Hesperornithiformes (Aves)
The Hesperornithiformes constitute the first known avian lineage to secondarily lose flight in exchange for the evolution of a highly derived foot-propelled diving lifestyle, thus representing the
Cranial kinesis in the late Cretaceous birds Hesperornis and Parahesperornis
-A recently discovered skull of the Cretaceous toothed diving bird Hesperornis permits evaluation of previous descriptions of the skull, analysis of cranial kinesis in hesperornithid birds, and
Dinosaur ossification centres in embryonic birds uncover developmental evolution of the skull
Analysis of embryonic bird skulls reveals dinosaur-like modular ossification patterns, which underpins the re-organization of skull architecture during bird evolution.
The Diet of Early Birds Based on Modern and Fossil Evidence and a New Framework for its Reconstruction
Birds are some of the most diverse organisms on Earth, with species inhabiting nearly every conceivable niche in every major biome. As such, birds are vital to our understanding of modern ecosystem...
Bird neurocranial and body mass evolution across the end-Cretaceous mass extinction: The avian brain shape left other dinosaurs behind
Questions about avian survivorship relative to other dinosaurs are interrogated using data from a new, nearly complete skull of Late Cretaceous bird Ichthyornis and shifts in bird body size across the Cretsaceous-Paleogene boundary are reassessed.


New light on the Origin of Birds and Crocodiles
Detailed evidence from the skull of Sphenosuchus, and from embryological and other resemblances between birds and crocodiles, suggests that these two groups are much more closely related than has
Mandible of Archaeopteryx provides an Example of Mosaic Evolution
The morphological distinctions between the lower jaws of reptiles and birds are studied, and the results have a direct bearing on the level of organization (morphological grade) of Archaeopteryx.
On the Mechanical Implications of the Avian Skull and Their Bearing on the Evolution and Classification of Birds
Preliminary investigations dealing with the relationship existing between the morphology of the bird's skull and its kinetic possibilities, appear to show that the thecodont ancestors of Birds, as
Routine comparison with Hesperornis, the only other Cretaceous bird sufficiently well known for comparison, brought the convergent condition mentioned above to light and showed that these jaws probably did not belong with that bird skeleton but are actually young mosasaur jaws which were washed into the same deposit with bird bones of similar size.
A New Partial Mandible of Ichthyornis
In 1872, O. C. Marsh described a new Cretaceous bird Ichthyornis dispar based on a posteranial skeleton and referred the toothed "Colonosaurus" jaws to IchthyORNis dispar stating that "there cannot now be a reasonable doubt that all are parts of the same bird".
The Ancestry of Birds
WALKER1 has restated the long-held belief that both birds and crocodiles evolved from thecodont ancestors, but he added the novel suggestion that these two groups arose from a common thecodont
Preliminary description of Hesperornis regalis, with notice of four other new species of Cretaceous birds
THE few remains of birds hitherto described from the Oretaceous deposits of this country, although of much interest, all pertained to comparatively small species, and belonged, apparently, to
Some aspects of the origin and evolution of birds of particular interest to neurology are outlined, with special emphasis on cranial morphology and on those avian orders most advantageous to neurologists.
  • P. Galton
  • Environmental Science
    Evolution; international journal of organic evolution
  • 1970
The purpose of this paper is to review various features relevant to this problem and to show that the arboreal "Proavis" was probably derived from a cursorial ground-living biped.