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Late Cretaceous neornithine from Europe (1 Viewer)

RSN

Rafael S. Nascimento
Brazil
Daniel J. Field, Juan Benito, Albert Chen, John W. M. Jagt & Daniel T. Ksepka

Late Cretaceous neornithine from Europe illuminates the origins of crown birds

Nature 579, 397–401(2020)
Published: 18 March 2020
https://doi.org/10.1038/s41586-020-2096-0

Abstract

Our understanding of the earliest stages of crown bird evolution is hindered by an exceedingly sparse avian fossil record from the Mesozoic era. The most ancient phylogenetic divergences among crown birds are known to have occurred in the Cretaceous period, but stem-lineage representatives of the deepest subclades of crown birds—Palaeognathae (ostriches and kin), Galloanserae (landfowl and waterfowl) and Neoaves (all other extant birds)—are unknown from the Mesozoic era. As a result, key questions related to the ecology, biogeography and divergence times of ancestral crown birds remain unanswered. Here we report a new Mesozoic fossil that occupies a position close to the last common ancestor of Galloanserae and fills a key phylogenetic gap in the early evolutionary history of crown birds. Asteriornis maastrichtensis, gen. et sp. nov., from the Maastrichtian age of Belgium (66.8–66.7 million years ago), is represented by a nearly complete, three-dimensionally preserved skull and associated postcranial elements. The fossil represents one of the only well-supported crown birds from the Mesozoic era, and is the first Mesozoic crown bird with well-represented cranial remains. Asteriornis maastrichtensis exhibits a previously undocumented combination of galliform (landfowl)-like and anseriform (waterfowl)-like features, and its presence alongside a previously reported Ichthyornis-like taxon from the same locality provides direct evidence of the co-occurrence of crown birds and avialan stem birds. Its occurrence in the Northern Hemisphere challenges biogeographical hypotheses of a Gondwanan origin of crown birds, and its relatively small size and possible littoral ecology may corroborate proposed ecological filters that influenced the persistence of crown birds through the end-Cretaceous mass extinction.

https://www.nature.com/articles/s41...XgSOvoRG3tLw0dgVvwxinbZMfrMB8nff4kfIRvScAGEE0
 
Kevin Padian, 2020

Poultry through time.

A newly discovered 66.7-million-year-old fossil bird excavated in Belgium provides us with the best evidence so far for understanding when the living groups of birds first evolved and began to diverge.

Nature 579: 351-352
https://www.nature.com/articles/d41586-020-00766-2

Free pdf:
https://media.nature.com/original/magazine-assets/d41586-020-00766-2/d41586-020-00766-2.pdf

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Oldest modern bird fossil looks like a duck from the back and a chicken from the front

https://www.sciencemag.org/news/2020/03/oldest-modern-bird-fossil-looks-duck-back-and-chicken-front

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Catch a Falling Star: Meet Asteriornis!

https://albertonykus.blogspot.com/2020/03/catch-falling-star-meet-asteriornis.html

===

Fred
 
Systematic palaeontology

Avialae Gauthier, 1986
Neornithes Gadow, 1892
Neognathae Pycraft, 1900
Pangalloanserae Gauthier and de Queiroz, 2001
Asteriornis maastrichtensis gen. et sp. nov.

Remarks. We use Avialae to refer to theropods crownward of Dromaeosauridae and Troodontidae. Neornithes is equivalent to the bird crown group (Aves sensu Gauthier, 1986). Pangalloanserae defines the most inclusive clade including Anser anser and Gallus gallus but not Passer domesticus (that is, the galloanseran total group). Further phylogenetic definitions are presented in the Supplementary Information.

Holotype. Natuurhistorisch Museum Maastricht (NHMM) 2013 008, a nearly complete, articulated skull including mandibles and associated postcranial remains preserved in four blocks. Preserved elements include the premaxillae, maxillae, nasals, frontals, laterosphenoid, basisphenoid, mesethmoid, left quadrate, left jugal,
right palatine and lower jaws. Associated postcranial elements include incomplete femora, tibiotarsi, tarsometatarsus and radius.

Etymology. Asteriornis, from the name of the Titan goddess Asteria and the Greek ornis for bird. In Greek mythology Asteria is the goddess of falling stars and transforms herself into a quail—attributes that are reflected by both the impending Cretaceous–Palaeogene (K–Pg) asteroid impact and the galloanseran affinities of Asteriornis. The specific epithet maastrichtensis reflects the provenance of the holotype—the
Maastricht Formation (the type locality of the Late Cretaceous Maastrichtian stage).

Locality and age. CBR-Romontbos Quarry, Eben-Emael, Liège, Belgium. Valkenburg Member (66.8–66.7 million years old24), Maastricht Formation, Late Maastrichtian, Cretaceous.

Fred

Extended Data Fig. 3 | Morphology of individually segmented skull elements from A. maastrichtensis (NHMM 2013 008). Dorsal, ventral and rostral views of the frontals show the nasals separated from their in situ position to illustrate the morphology of the nasofrontal contact. Scale bars, 1 cm.
 

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