Filamentous Integuments in Nonavialan Theropods and Their Kin: Advances and Future Perspectives for Understanding the Evolution of Feathers

@inproceedings{Xu2020FilamentousII,
  title={Filamentous Integuments in Nonavialan Theropods and Their Kin: Advances and Future Perspectives for Understanding the Evolution of Feathers},
  author={Xing Xu},
  year={2020}
}
  • Xing Xu
  • Published 2020
  • Environmental Science
The discovery of Sinosauropteryx in 1996 marks the beginning of a new era in the research on the origin and early evolution of feathers. Subsequent discoveries of dinosaur fossils preserving feathers and feather-like integumentary appendages from both the Jurassic and Cretaceous deposits of China and other countries demonstrate a longer and more complex evolutionary history of feathers before the origin of birds than was previously thought. Currently, there are still many issues that continue… 
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References

SHOWING 1-10 OF 89 REFERENCES
Branched integumental structures in Sinornithosaurus and the origin of feathers
TLDR
Observations of the filamentous integumental appendages of the basal dromaeosaurid dinosaur Sinornithosaurus millenii indicate that they are compound structures composed of multiple filaments that are unique to avian feathers, which strongly corroborate the hypothesis that the integumentals of SinORNithosaurus are homologous with avan feathers.
THE ORIGIN AND EARLY EVOLUTION OF FEATHERS:INSIGHTS FROM RECENT PALEONTOLOGICAL AND NEONTOLOGICAL DATA
TLDR
Five major morphogenesis events are inferred to have occurred sequentially early in feather evolution before the origin of the Aves, and the function of the first feather is inferred to be neither related to flight nor to insulation.
Exceptional dinosaur fossils show ontogenetic development of early feathers
TLDR
An early-juvenile specimen and a late- juvenile specimen, both referable to the oviraptorosaur Similicaudipteryx, recovered from the Lower Cretaceous Yixian Formation of western Liaoning, China are described, suggesting that early feathers were developmentally more diverse than modern ones and that some developmental features have been lost in feather evolution.
New specimen of Archaeopteryx provides insights into the evolution of pennaceous feathers
TLDR
An analysis of the phylogenetic distribution of pennaceous feathers on the tail, hindlimb and arms of advanced maniraptorans and basal avialans strongly indicates that these structures evolved in a functional context other than flight, most probably in relation to display, as suggested by some previous studies.
The morphology of neoptile feathers: Ancestral state reconstruction and its phylogenetic implications
  • C. Foth
  • Biology
    Journal of morphology
  • 2011
TLDR
The morphology of neoptile feathers is more diverse and even shows a clear phylogenetic signal, and it is necessary to expand the spectrum of “model organisms” to species with bilaterally symmetric ne optile feathers and compare differences in the frequency of feather development from a phylogenetic point of view.
The early evolution of feathers: fossil evidence from Cretaceous amber of France
TLDR
Fossil evidence of an intermediate and critical stage in the incremental evolution of feathers which has been predicted by developmental theories but hitherto undocumented by evidence from both the recent and the fossil records is reported.
The Evolutionary Origin And Diversification Of Feathers
TLDR
The developmental theory proposes that feathers evolved through a series of evolutionary novelties in developmental mechanisms of the follicle and feather germ, and the discovery of primitive feather fossils on nonavian theropod dinosaurs documents that feathers evolve and diversified in nonavIAN theropods before the origin of birds and before theorigin of flight.
A Jurassic ornithischian dinosaur from Siberia with both feathers and scales
TLDR
A seemingly feathery nontheropod dinosaur from the Jurassic of Siberia shows that feathers were not unique to the ancestors of birds and may even have been quite widespread, and feathers may thus have been present in the earliest dinosaurs.
Adaptation to the sky: Defining the feather with integument fossils from mesozoic China and experimental evidence from molecular laboratories.
  • C. Chuong, Ping Wu, L. Hou
  • Biology
    Journal of experimental zoology. Part B, Molecular and developmental evolution
  • 2003
TLDR
A series of fossil discoveries representing intermediate forms of feathers or feather-like appendages from dinosaurs and Mesozoic birds from the Jehol Biota of China are reviewed and a set of criteria for true avian feathers is developed.
A pre-Archaeopteryx troodontid theropod from China with long feathers on the metatarsus
TLDR
The extensive feathering of this specimen, particularly the attachment of long pennaceous feathers to the pes, sheds new light on the early evolution of feathers and demonstrates the complex distribution of skeletal and integumentary features close to the dinosaur–bird transition.
...
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