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RE: Sleeping Dinosaur
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First Birds Might Have Flown on Four Wings

Birdlike dinosaurs, such as Microraptor and Sinornithosaurus, are known to have had long, sturdy feathers on their hindlimbs. But until now, researchers were not sure whether the earliest birds had already abandoned this extra plumage when they emerged to take to the Cretaceous skies over 100 million years ago.
The researchers, led by Xing Xu, a paleontologist at the Institute of Geology and Paleontology in Shandong, China, found evidence of feathers on the hindlimbs of 11 basal bird specimens (gathered from the Lower Cretaceous Jehol Group in China).

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Eosinopteryx feathered dinosaur offers clues on bird evolution

A newly-discovered feathered dinosaur pre-dates those birds were thought to have evolved from, a Southampton palaeontologist claims.
The Eosinopteryx was a 30cm flightless dinosaur whose remains were found in north-eastern China.

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Eosinopteryx
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New dinosaur fossil challenges bird evolution theory

The discovery of a new bird-like dinosaur from the Jurassic period challenges widely accepted theories on the origin of flight.
Co-authored by Dr Gareth Dyke, Senior Lecturer in Vertebrate Palaeontology at the University of Southampton, the paper describes a new feathered dinosaur about 30 cm in length which pre-dates bird-like dinosaurs that birds were long thought to have evolved from.

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RE: Sleeping Dinosaur
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Title: Gender identification of the Mesozoic bird Confuciusornis sanctus
Authors: Anusuya Chinsamy, Luis M. Chiappe, Jesús Marugán-Lobón, Gao Chunling & Zhang Fengjiao

Hundreds of specimens of the beaked bird Confuciusornis sanctus have been recovered from Early Cretaceous lake deposits of northeastern China. These birds show remarkable variation in size and plumage, with some displaying two long, central ornamental rectrices (tail feathers) and others lacking them altogether. Although, traditionally specimens with ornamental rectrices were interpreted as males and those without them as females, this supposed sexual dimorphism has remained unconfirmed. Here we report on the discovery of medullary bone, a tissue unique to reproductively active female birds, in a specimen of C. sanctus (DNHM-D1874) lacking these feathers. Our discovery constitutes the first case of gender identification in a Mesozoic bird, and it provides undisputed evidence that individuals of C. sanctus without ornamental rectrices are females. By permitting gender identification in C. sanctus, our results provide insight into the onset of sexual maturity and attainment of adult body size of this and other early birds.

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Evolution of bird flight
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New evidence of dinosaurs' role in the evolution of bird flight

A new study looking at the structure of feathers in bird-like dinosaurs has shed light on one of nature's most remarkable inventions - how flight might have evolved.
Academics at the Universities of Bristol, Yale and Calgary have shown that prehistoric birds had a much more primitive version of the wings we see today, with rigid layers of feathers acting as simple airfoils for gliding.

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Dinosaur feathers
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Dinosaur feathers 'developed for courtship'

Research suggests that not only did wings evolve in dinosaurs earlier than previously thought, they may have evolved merely for courtship displays.
A study in Science describes three Ornithomimosaur specimens - distantly related to birds - from Canada.
Both juvenile and adult specimens had evidence of downy feathers, but only an adult had wing-like structures.

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Fossil egg
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Fossil egg discovered in Spain

The 'missing link' which proves the relationship between dinosaurs and birds may have been found.
It is a widely-held view that dinosaurs and birds share the same heritage, and an egg discovered in the Montsec area of Lleida, near Catalonia in Eastern Spain, shares characteristics of both species.
The dinosaur egg, dating back 70 to 83 million years, has an oval shape, similar in appearance to a chicken egg, and an 'air bag' inside which birds today use to breathe in the last stages of its development.
The new type of dinosaur egg has been given the scientific name of Sankofa pyrenaica and is the only dinosaur egg in the world to have an oval shape, similar to that of chicken eggs.

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Dinosaur-Bird Transition
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 Developmental Timing Offers Another Window Into Dinosaur-Bird Transition

A new study has used skull anatomy to show that the evolution of birds from dinosaurs may have resulted from a drastic change in dinosaur development.
In a study published this week in the journal Nature, researchers from Harvard University, the Museum, the New York Institute of Technology, The University of Texas at Austin, and the Autonomous University of Madrid report evidence that while many dinosaurs took years to reach sexual maturity, birds sped up the developmental clock, which led them to retain the physical characteristics of baby dinosaurs.
The paper adds another dimension to a long history of research on the theropod origin of birds.

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Caudipteryx
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  Dino-bird was prone to osteoarthritis

Dinosaurs might be the oldest victims of osteoarthritis, say researchers.
Bruce Rothschild at the University of Kansas in Lawrence and colleagues have revealed that Caudipteryx, a dino-bird that lived 130 million years ago, was prone to osteoarthritis - perhaps the oldest such diagnosis on record.
Some modern birds are susceptible to osteoarthritis, the degeneration of bone and cartilage in joints.

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Bonapartenykus ultimus
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 New dinosaur 'proves' evolution into birds

A dinosaur discovered in Patagonia has been called the 'missing link' between the ancient creatures and modern birds.



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