Posted on 09/22/2006 6:27:23 AM PDT by Tokra
The earliest known ancestor of modern-day birds took to the skies by gliding from trees using primitive feathered wings on their arms and legs, according to new research by a University of Calgary paleontologist. In a paper published in the journal Paleobiology, Department of Biological Sciences PhD student Nick Longrich challenges the idea that birds began flying by taking off from the ground while running and shows that the dinosaur-like bird Archaeopteryx soared using wing-like feathers on all of its limbs.
"The discussions about the origins of avian flight have been dominated by the so-called 'ground up' and 'trees down' hypotheses," Longrich said. "This paper puts forward some of the strongest evidence yet that birds descended from arboreal parachuters and gliders, similar to modern flying squirrels."
The first fossil of the Jurassic-era dinosaur Archaeopteryx lithographica was discovered in Germany in 1861, two years after Charles Darwin published his theory of evolution in On The Origin of Species. Since then, eight additional specimens have been unearthed and Archaeopteryx is considered the best evidence that birds evolved from dinosaurs since it had both feathers and a bird-like wishbone, along with classic reptilian features of a long bony tail, claws and teeth.
Although scientists immediately noticed feather-like structures on the hind limbs, they were dismissed as insulating body feathers that didn't play a role in the animal's flight. It wasn't until several four-winged dinosaurs in China were described in 2002 that researchers began to re-examine Archaeopteryx's legs.
"The idea of a multi-winged Archaeopteryx has been around for more than a century, but it hasn't received much attention," Longrich said. "I believe one reason for this is that people tend to see what they want or expect to see. Everybody knows that birds don't have four wings, so we overlooked them even when they were right under our noses."
Under the supervision of professor Anthony Russell, Longrich examined Archaeopteryx fossils and determined that the dinosaur's leg feathers have an aerodynamic structure that imply its rear limbs likely acted as lift-generating "winglets" that played a significant role in flight.
Nope, it's not:
http://www.chebucto.ns.ca/Environment/NHR/archaeopteryx.html
"The authoritative rebuttal of this view comes in a paper published in Science (Vol 232, 2 May, 1986, pp. 622-625) by Alan Charig, Frank Greenaway, Angela Milner, Cyril Walker and Peter Whybrow unequivocally entitled Archaeopteryx Is Not a Forgery. Their arguments are technical and detailed but in essence they show that there is no evidence of such 'doctoring' of the slab; that mineral-filled hairline fissures extend from the feathers and into the bones of the animal rpoving that they are from one and the same source; that minerological evidence conclusively shows that the slab and counterslab connect together and that differences in sedimentary texture between the two are perfectly in keeping with such deposits and the ways in which they are created. They point out that in addition there are remains of five Archaeopteryx discovered at different times and places and under well documented conditions. In only one of these specimens is the state of preservation such that the presence of feathers cannot unequivocally be established."
Even AIG says it isn't a fraud. Of course, they ignore all it's transitional features, and call it a "True Bird"...
http://www.answersingenesis.org/docs2/4254news3-24-2000.asp
Must have been harsh on the first birds having to climb trees and then jumping to see if they had enough feathers yet.
"It's like cutting hair. It's relatively easy to cut it off, while getting it back on again is impossible."
That may be the weakest analogy I have heard on this subject! Congratulations!
I don't know about you, but I wish it were true. Then I could save all that money every month getting it cut again after IT GROWS BACK!!!!
Translation:
"Don't try to put your facts on me mister! I KNOW the truth!! All that evidence is just devil-induced trickery!!!!"
Probably no harder than the flying squirrels and flying foxes. Check back with them in 10 million years and I bet they will have evolved into a whole new species of flying mammal.
Kind of like how the bat evolved into a flying mammal.
Been watching birds in the yard lately. Some of them are not graceful at all. Most plan their moves but some just jump. Saw a gray jay fall on his beak when he started to take off from the porch and stopped short at the edge. The small birds don't fly so much as jump and grab. They'll end up hanging from a branch upside down very often. They probably learned to fly by climbing trees and jumping, which the squirrels do now whether they have airfoil or not.
From my office window in the midwest, I can see several species of birds flying around at any given time, including hawks, vultures, and an occasional Eagle.
But don't let those pesky facts get in the way again.
Why is it necessary for all sytems to have evolved simultaneously? Why is it not possible for multiple features to have evolved simultaneously? Why is it not possible for some features, or groups of features, to be of some benefit without the ability to fly?
Making wild assertions isn't convincing.
As does evolution.
"arboreal"
Somehow this word reminds me of Al Bore, aka totem face.
"So, I guess the scientists secretly built fake fossils with feathers, wishbone, claws and teeth just to trick everybody?
"It's been done before.
When and where?
You are correct - if you watch birds you will notice they do a lot of jumps and hops rather than full fledged flight, unless they are travelling a long distance. Or unless they are dive bombing Mr. Jinks, my cat.
Gliding requires large lift areas. I suspect their (somewhat) immediate ancestors did not have powered flight but instead used assisted gliding.
But not as funny.
Rocky: Bullwinkle, it says here that for you to inherit the fortune, you have to spend the weekend in the ancestral home; Abominable Manor.
Bullwinkle: That's no problem. I've been living in an abominable manner all my life.
"I'm still in common sense.
I assume you believe 'common sense' is always correct?
Is it common sense to believe that small bits can never accumulate and become large bits?
"When and where?"
At museums of natural history throughout the country.
I take it you have never seen the enormous clouds of geese during spring and fall?
I see hawks, falcons every day in my travels. I also see owls and eagles more than once a week.
I noticed you focused on the raptors, which as predators are necessarily fewer in number than their prey. This handily ignores a great many other birds.
BTW, there are about 4500 species of mammal and about 10,000 species of bird.
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