birds

[morgangilson]

what is name of earliest bird known and when did it live?

[jake-the-peg]

http://news.nationalgeographic.com/news/2004/10/1021_041021_bird_embryo.html

121 million years

archaeopteryx dates from 150 Million years ago

When Clanad was on his Evolution-is-bunk kick a week or two ago he claimed birds had been found that pre-dated archaeopterix but he didn't make clear whether he'd found a reference to a specemin earlier than 150 Million years or whether he was contesting the date

It could be he was referring to Jinfengopteryx elegans

This has recently been found and it's age is not yet clear - one of the researchers is quoted as saying it's more primative than archaeoptryx but of course more primative does not mean older. Today's jellyfish are more primatie than my Grandmother!

[Clanad]

Thank you jake-the-peg, for such a glowing introduction... however your reference to the Chinese fossil should be taken with a large grain of salt...

WASHINGTON (BP)--An independent group of scientists has described as unfounded National Geographic Society's report late last year of "a true missing link in the complex chain that connects dinosaurs to birds."

A panel of paleontologists and ornithologists released their findings April 6, confirming speculation by outside scientists that National Geographic Society's media blitz touting a feathered dinosaur fossil lacked independent scientific confirmation.

The panel was convened by National Geographic after a number of media reports, such as one in USA Today, questioned the supposed discovery.

Further examination by the scientists of the fossil has revealed that it is a composite of at least two different animals. The fossil was smuggled into the United States from China and was sold for $80,000 to the owner of a dinosaur museum in Monticello, Utah, before it eventually landed in the halls of the National Geographic Society in Washington.

Contd.

 

[Clanad]

Fact is, although the center of a very contentious debate, there is some question about whether Archaeopteryx, supposedly 150 million years old, is really the ancestor of birds. Bones of a modern bird were found in the same geological strata as Archaeopteryx by James Jensen (Science pgs. 199-284, 1978). In Science News, John Ostrom, a leading bird paleontologist, stated in response to this report: "It is obvious we must now look for ancestors of flying birds in a period of time much older than that in which Archaeopteryx lived."

Recent discoveries at the Dockum Formation near Post, Texas by Sankar Chatterjee pushed back the date of the earliest known bird to 225 million years ago based on evolutionary reckoning. Two crow-sized birds he calls Protoavis date 75 million years older than Archaeopteryx. They have several features in the skull and shoulder which are more birdlike than Archaeopteryx.

Archaeopteryx couldn�t be the ancestor of birds if a more "modern" type bird than has been found in rock 75 million years older (Nature, pgs. 322-677, 1986). Say what you will about my position, this the evidence of scientific investigation, not evolution-is-bunk, etc...

"but of course more primative does not mean older"... What, may I ask, is that supposed to mean if not bunk?

[jake-the-peg]

More primitive does not have to mean older when applied to a particular specemin

A shark swimming in the sea today is more primitive and younger than a cod used in fish and chips twenty years ago

I'd have thought that was obvious 

As for protoavis I think this from Berkley puts the situation reasonably fairly:

Is Chatterjee right? One problem with Protoavis is that the bones were not found in an articulated skeleton, and had to be pieced together. In this situation, there is always the possibility of mixing up bones from different organisms. This has happened often enough in the past to make many paleontologists wary when discussing Protoavis. Dr. Kevin Padian of the UC Museum of Paleontology believes that Protoavis is probably a mixture of two or more different skeletons, and several other paleontologists concur in this interpretation. Other paleontologists accept Protoavis as a single organism but put its birdlike features down to convergent evolution: Protoavis might be an early dinosaur or other diapsid that had evolved some birdlike features but was not on the lineage leading directly to modern birds. Several other Triassic diapsids, including forms not directly related to the archosaurs, show some convergent features with birds. The true story of Protoavis will probably remain a controversial topic for paleontologists for quite some time.