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Yutyrannus huali
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T. rex relative is biggest ever feathered animal

A newly described relative of Tyrannosaurus rex is the largest known feathered animal - living or extinct.
The feathered meat-eating dinosaur lived about 125 million years ago and is estimated to have weighed a whopping 1,400kg as an adult.

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Microraptor Iridescent Feathers
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 Iridescent, Feathered Dinosaur: New Evidence That Feathers Evolved to Attract Mates

The detailed feather pattern and colour of Microraptor--a pigeon-sized, four-winged dinosaur that lived about 120 million years ago--had a glossy iridescent sheen.
Its tail was narrow and adorned with a pair of streamer feathers, suggesting the importance of display in the early evolution of feathers, say scientists reporting the findings in this week's issue of the journal Science.
By comparing the patterns of pigment-containing organelles from a Microraptor fossil to those in modern birds, the scientists determined that the dinosaur's plumage was iridescent with a glossy sheen like the feathers of a modern crow.
The new fossil is the earliest record of iridescent colour in feathers.

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Earliest bird extinction
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Old fossils solve mystery of earliest bird extinction

Most early bird species suffered from the same catastrophic extinction as the dinosaurs, new research has shown.
The meteorite impact that coincided with the disappearance of the dinosaurs 65 million years ago, also saw a rapid decline in primitive bird species.
Only a few bird groups survived through the mass extinction, from which all modern birds are descended.

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Primitive Birds
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Primitive Birds Shared Dinosaurs Fate

A new study puts an end to the longstanding debate about how archaic birds went extinct, suggesting they were virtually wiped out by the same meteorite impact that put an end to dinosaurs 65 million years ago.
For decades, scientists have debated whether birds from the Cretaceous period - which are very different from today's modern bird species - died out slowly or were killed suddenly by the Chicxulub meteorite. The uncertainty was due in part to the fact that very few fossil birds from the end of this era have been discovered.
Now a team of palaeontologists led by Yale researcher Nicholas Longrich has provided clear evidence that many primitive bird species survived right up until the time of the meteorite impact.

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Protofeathers
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Dinosaur feathers found in Alberta amber

Feathers believed to be from dinosaurs have been found beautifully preserved in Alberta amber.
The primitive, hair-like feathers known as protofeathers likely belonged to theropods - dinosaurs similar to tiny Tyrannosaurus rexes - that roamed the swampy forests of Alberta 80 million years ago

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Dinosaur feathers
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Dinosaur feather evolution trapped in Canadian amber

Samples of amber in western Canada containing feathers from dinosaurs and birds have yielded the most complete story of feather evolution ever seen.
Eleven fragments show the progression from hair-like "filaments" to doubly-branched feathers of modern birds.
The analysis of the 80-million-year-old amber deposits is presented in Science.

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Archaeopteryx
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A chicken-sized dinosaur fossil found in China may have overturned a long-held theory about the origin of birds.
For 150 years, a species called Archaeopteryx has been regarded as the first true bird, representing a major evolutionary step away from dinosaurs.
But the new fossil suggests this creature was just another feathery dinosaur and not the significant link that palaeontologists had believed.

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Flight evolution
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Flap-running in birds is key to flight evolution
 
The ungainly sight of a bird furiously flapping its wings as its spindly legs propel it forward could be peek at evolutionary history.
"Flap-running", researchers say, may have been a key step in the evolution of flight.
Experiments with pigeons have shown that it helps the birds ascend slopes and scientists suggest the earliest flightless birds might have used the same technique.

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Avian olfaction
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Evolution of the sense of smell in dinosaurs and birds

Everyone knows birds aren't exactly bloodhounds. The party line has been that the evolution of flight in birds favoured vision and balance over olfaction, and so the sense of smell was reduced. A new study overturns that perception, showing that as birds evolved from theropod dinosaurs their sense of smell was maintained and actually increased in basal birds. The olfactory bulbs of the brain, where information on odours is processed, were measured in 157 species of non-avian dinosaurs, fossil birds, and modern-day birds. For many of the fossil species, CT scanning provided the first-ever glimpse into brain and olfactory bulb structure. Rather than diminishing, the olfactory bulbs of the earliest birds were still basically dinosaur-sized, and even increased in relative size among early birds, including in the earliest members of the radiation of modern-day (neornithine) birds. As a result, the sense of smell remained very important to early birds, even as they were simultaneously honing other parts of their "flight computer," and early birds may have used odours to a much greater extent in navigation and foraging than do most birds today. Another key finding is the unexpected importance of smell for non-avian theropods. Many dinosaur species that we usually regard as having used mostly vision, such as Velociraptor, Bambiraptor and Troodon, almost certainly also relied on smell.
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RE: Sleeping Dinosaur
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Rare isotopes preserved in fossil teeth could serve as an ancient thermometer.

Tyrannosaurus rex is often portrayed as a cold-blooded killer, but whether the Cretaceous-era dinosaur actually had a slow, reptilian-like metabolism or a faster, more bird-like metabolism is still a mystery.
Now a new technique using rare isotopes preserved in tooth enamel is proving to be a reliable way of determining body temperatures of recently extinct animals like woolly mammoths and researchers are hoping the method will work on even older fossils, including dinosaurs.
A team of researchers led by Robert Eagle, a biologist at the California Institute of Technology in Pasadena, California, found that rare, heavy isotopes of carbon-13 and oxygen-18 clump together differently depending on temperature.

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