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Posts Tagged ‘flight’

Trove of Dinosaur Feathers Found in Canadian Amber

15 Sep
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Discovery

An extraordinary collection of ancient feather fragments preserved in amber has opened a window into a lost world, one that now appears populated by dinosaurs covered in plumage as rich and varied as that of modern birds.

The feathers date to the end of the Cretaceous, about 85 to 70 million years ago. At that time, the forerunners of birds were well on their way to taking wing; dinosaurs like Epidexipteryx and Limosaurus, discovered in China in the last decade and dating to approximately 160 million years ago, possess relatively bird-like bone structures and hints of what might have been feathers.

Those hints have been interpreted -- and given life in eye-popping artist renditions -- as feathers, an interpretation that was plausible but still inconclusive.

But the latest fossils, found in Alberta and described Sept. 16 in Science, leave little doubt. The age of dinosaurs was a feathery one.

"These lovely specimens of significantly older, smaller dinosaurs from China have got some sort of covering about them. But you can't tell if it's hair or feathers because the fossils have undergone the ravages of time," said paleontologist Alex Wolfe of the University of Alberta, a co-author of the new study. "Those fossils don't preserve the kind of detail that we have in amber, which doesn't fossilize but entombs an object."

On the following pages, Wired.com looks at the new trove of feathers.

Above:

Feathers in Amber

Image: McKellar et al./Science

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See Also:

Citations: “A Diverse Assemblage of Late Cretaceous Dinosaur and Bird Feathers from Canadian Amber.” By Ryan C. McKellar, Brian D. E. Chatterton, Alexander P. Wolfe, Philip J. Currie. Science, Vol. 333 Issue 6049, September 16, 2011.

“Fossilized Feathers.” By Mark A. Norell. Science, Vol. 333 Issue 6049, September 16, 2011.

 
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Bird Flight Might Have Started With Legs, Not Wings

18 Aug

To take flight, first strengthen your legs: It sounds like a self-help proverb, but it could explain how birds first took wing.

Until now, most explanations of the evolution of flight have assumed that going airborne was an end in itself, driven by the need of some early dinosaur to glide down from trees or up off the ground.

But flight could have instead been an incidental benefit of beefier muscles needed to compensate for losing a heat-generating protein.

“Flight is seen as the hallmark of bird evolution,” said developmental biologist Stuart Newman of the New York Medical College. “But you can make the argument that the particular form bird skeletons took that opened the way for flight was a side effect.”

Newman’s research shows that all birds and reptiles lack a single gene that codes for a protein called UCP1 or, with a nod to its function, thermogenin. It’s an essential part of the metabolic reaction that burns brown fat, helping bodies self-regulate internal temperature and generate heat without shivering.

Thermogenin’s absence from birds and reptiles hints at its loss in some early common ancestor, with the thermogenin-retaining relative later giving rise to mammals. But whereas reptiles became cold-blooded, basking in sunshine when needed, birds stayed warm-blooded.

Image: Markiza/Flickr

As Newman describes in a September Bioessays paper, the key to their warmth is muscles. Muscles are powerful generators of heat, which is a byproduct of the chemical reaction that makes them contract. Bird muscles also have further heat-generating adaptations. And birds are, in a word, jacked.

In ounce-for-ounce comparison, mammals and reptiles are scrawny weaklings next to birds. And it’s not just avian breast muscles that are pumped, as would be expected in flyers, but their legs too.

“My hypothesis is that birds basically salvaged their existence by developing very large skeletal muscles,” said Newman.

Once heavily muscled, he believes proto-birds would naturally have gravitated towards bipedalism, which isn’t a particularly challenging transition. Indeed, walking on two legs was widespread in dinosaurs.

Bipedality releases upper limbs, both literally and in evolutionary terms, allowing them to accumulate large mutations with relatively little risk. Combine that with powerful breast muscles, and wings would soon follow.

Testing Newman’s hypothesis may not be possible, as it would require comparing early bird and dinosaur skeletons and genes, and DNA is lost in the fossil record. But that flight could plausibly have been a fortunate side effect of some unrelated adaptation, rather than the original driver of bird development, is a useful evolutionary lesson.

Newman also suggests people at least reconsider the phenomenon of flightlessness in birds, which is generally portrayed in terms of loss.

“It’s almost universally accepted that all flightless birds come from flighted ancestors,” said Newman. “That might be true — but maybe it’s flying birds that have flightless ancestors. Maybe flightless birds were the leading edge.”

Top image: Lip Kee Yap/Flickr

See Also:

Citation:”Thermogenesis, muscle hyperplasia, and the origin of birds.” By Stuart Newman. Bioessays, Vol. 33 No. 9, September 2011.

 
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Space Shuttle Atlantis Launch Video: The Final Flight

08 Jul


At 11:26 ET Friday, space shuttle Atlantis flew up in the sky toward the International Space Station, marking an end of an era: It was the last aircraft to launch as part of NASA’s space shuttle program.

Atlantis will carry four astronauts during the 12-day mission, bring supplies and spare parts to the International Space Station and conduct an experiment to test new refueling and repair technology for satellites in orbit, after which it will return to Earth and retire.

SEE ALSO: Space Shuttle Launch: Photos from the Final Atlantis Flight

If you’ve missed the live stream of the launch, you can see it in the archived video below. The actual liftoff starts somewhere around 18:00 in the video.

Photos from the Final Atlantis Flight

Stay tuned. We’ll keep updating this gallery with new photos.


Liftoff




Photo courtesy of NASA.


Liftoff




Photo courtesy of NASA.


Liftoff




Photo courtesy of NASA.


Liftoff




Photo courtesy of NASA.


Solid Rocket Booster Separation




Photo courtesy of NASA.


Liftoff




Photo courtesy of Ryan Matzner.


Liftoff




Photo courtesy of Ryan Matzner.


Liftoff




Photo courtesy of Ryan Matzner.


Liftoff




Photo courtesy of Ryan Matzner.


Liftoff




Photo courtesy of Ryan Matzner.


Liftoff




Photo courtesy of Ryan Matzner.


Liftoff




Photo courtesy of Ryan Matzner.


Liftoff




Photo courtesy of Ryan Matzner.


Liftoff




Photo courtesy of Ryan Matzner.


Liftoff




Photo courtesy of Ryan Matzner.


Liftoff




Photo courtesy of Ryan Matzner.


Liftoff




Photo courtesy of Ryan Matzner.


Liftoff




Photo courtesy of Ryan Matzner.


Mashable Media Badge




Photo courtesy of Ryan Matzner.


NPR Tweeted




Photo courtesy of Ryan Matzner.


Official Launch M&Ms




Photo courtesy of Ryan Matzner.


Elmo Reports Launch




Photo courtesy of Ryan Matzner.


Media Getting Signals




Photo courtesy of Ryan Matzner.


@SethGreen Tweeted




Photo courtesy of Ryan Matzner.


Tweetup Participants




Photo courtesy of Ryan Matzner.


Tweetup Participants




Photo courtesy of Ryan Matzner.


Tweetup Badge




Photo courtesy of Ryan Matzner.


Tweetup Participants




Photo courtesy of Ryan Matzner.


Tweetup Participants




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Tweetup Participants




Photo courtesy of Ryan Matzner.


@schierholz Handed Out M&Ms




Photo courtesy of Ryan Matzner.


@schierholz Tweeted




Photo courtesy of Ryan Matzner.


@schierholz's Badge




Photo courtesy of Ryan Matzner.


Shuttle Atlantis




Shuttle Atlantis moves into the Vehicle Assembly Building.

Photo courtesy of NASA.


Atlantis Sunrise




The sun rises over the launch pad at NASA's Kennedy Space Center in Florida.

Photo courtesy of NASA.


Atlantis Sunset




Sunset over Launch Pad 39A before the Raffaello multi-purpose logistics module (MPLM) is delivered.

Photo courtesy of NASA.


Atlantis Sunrise




Another sun rises over the Shuttle Atlantis.

Photo courtesy of NASA.


The Crew Celebrates




The STS-135 crew wave American flags in honor of Independence Day. From left: Commander Chris Ferguson, Pilot Doug Hurley, and Mission Specialists Sandy Magnus and Rex Walheim.

Photo courtesy of NASA.


The Crew Heads for Final Launch Preparation




The STS-135 team departs for the Astronaut Crew Quarters in Kennedy's Operations and Checkout Building.

Photo courtesy of NASA.


Firing Room 4




In Firing Room 4, NASA team members prepare for launch.

Photo courtesy of NASA.


Launch Pad




Atlantis was "hard down" at its seaside launch pad by 3:29 a.m. EDT on Wednesday, June 1.

Photo courtesy of NASA.


Atlantis Flag




The Atlantis flag flutters below the American flag.

Photo courtesy of Ryan Matzner.


Launch Pad




A view of the launch pad from across the water.

Photo courtesy of Ryan Matzner.


Media Gathers




News crews prepare their equipment at tents near the launch pad.

Photo courtesy of Ryan Matzner.


Media Tents




Two-tier media tents provide better views of the Atlantis.

Photo courtesy of Ryan Matzner.


Launch Clock




Ryan Matzner, lead strategist at Fueled, a mobile app development firm, stands in front of the countdown-to-launch clock.

Photo courtesy of Ryan Matzner.


Media Tripods




Media stakes out their turf with tripods aimed at the shuttle launch.

Photo courtesy of Ryan Matzner.


Tweetup




Media and spectators alike participate in the lunch Tweetup.

Photo courtesy of Ryan Matzner.


En Route




The van will lead the procession of astronauts to the shuttle.

Photo courtesy of Ryan Matzner.


En Route




The astronauts en route to the launch pad.

Photo courtesy of Ryan Matzner.


En Route




Precious cargo on the way to the launch pad.

Photo courtesy of Ryan Matzner.


Vehicle Assembly Building




An impressive spectacle in itself, the Vehicle Assembly Building has been used to assemble NASA vehicles since 1968. It is the largest single-story building in the world.

Photo courtesy of Ryan Matzner.


Vehicle Assembly Building




A view of the vehicle assembly building.

Photo courtesy of Ryan Matzner.

BONUS: Amazing Photographs From Endeavour’s Last Voyage

NASA recently released these breathtaking images from the last voyage of Endeavour following its return from space last month. Until October 2010, it was believed that the Endeavour mission would be the last space shuttle flight — now Atlantis is set to take that honor.


Endeavour's final voyage





Endeavour's final voyage





Endeavour's final voyage





Endeavour's final voyage





Endeavour's final voyage





Endeavour's final voyage





Endeavour's final voyage





Endeavour's final voyage





Endeavour's final voyage





Endeavour's final voyage





Endeavour's final voyage





Endeavour's final voyage




More About: flight, NASA, space, space shuttle, Space Shuttle Atlantis, video

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