Posted on 04/05/2006 10:32:31 AM PDT by PatrickHenry
Paleontologists have discovered fossils of a species that provides the missing evolutionary link between fish and the first animals that walked out of water onto land about 375 million years ago. The newly found species, Tiktaalik roseae, has a skull, a neck, ribs and parts of the limbs that are similar to four-legged animals known as tetrapods, as well as fish-like features such as a primitive jaw, fins and scales.
These fossils, found on Ellesmere Island in Arctic Canada, are the most compelling examples yet of an animal that was at the cusp of the fish-tetrapod transition. The new find is described in two related research articles highlighted on the cover of the April 6, 2006, issue of Nature.
"Tiktaalik blurs the boundary between fish and land-living animal both in terms of its anatomy and its way of life," said Neil Shubin, professor and chairman of organismal biology at the University of Chicago and co-leader of the project.
Tiktaalik was a predator with sharp teeth, a crocodile-like head and a flattened body. The well-preserved skeletal material from several specimens, ranging from 4 to 9 feet long, enabled the researchers to study the mosaic pattern of evolutionary change in different parts of the skeleton as fish evolved into land animals.
The high quality of the fossils also allowed the team to examine the joint surfaces on many of the fin bones, concluding that the shoulder, elbow and wrist joints were capable of supporting the body-like limbed animals.
"Human comprehension of the history of life on Earth is taking a major leap forward," said H. Richard Lane, director of sedimentary geology and paleobiology at the National Science Foundation. "These exciting discoveries are providing fossil 'Rosetta Stones' for a deeper understanding of this evolutionary milestone--fish to land-roaming tetrapods."
One of the most important aspects of this discovery is the illumination of the fin-to-limb transition. In a second paper in the journal, the scientists describe in depth how the pectoral fin of the fish serves as the origin of the tetrapod limb.
Embedded in the fin of Tiktaalik are bones that compare to the upper arm, forearm and primitive parts of the hand of land-living animals.
"Most of the major joints of the fin are functional in this fish," Shubin said. "The shoulder, elbow and even parts of the wrist are already there and working in ways similar to the earliest land-living animals."
At the time that Tiktaalik lived, what is now the Canadian Arctic region was part of a landmass that straddled the equator. It had a subtropical climate, much like the Amazon basin today. The species lived in the small streams of this delta system. According to Shubin, the ecological setting in which these animals evolved provided an environment conducive to the transition to life on land.
"We knew that the rocks on Ellesmere Island offered a glimpse into the right time period and the right ancient environments to provide the potential for finding fossils documenting this important evolutionary transition," said Ted Daeschler of the Academy of Natural Sciences in Philadelphia, a co-leader of the project. "Finding the fossils within this remote, rugged terrain, however, required a lot of time and effort."
The nature of the deposits where the fossils were found and the skeletal structure of Tiktaalik suggests the animal lived in shallow water and perhaps even out of the water for short periods.
"The skeleton of Tiktaalik indicates that it could support its body under the force of gravity whether in very shallow water or on land," said Farish Jenkins, professor of organismic and evolutionary biology at Harvard University and co-author of the papers. "This represents a critical early phase in the evolution of all limbed animals, including humans--albeit a very ancient step."
The new fossils were collected during four summers of exploration in Canada's Nunavut Territory, 600 miles from the North Pole, by paleontologists from the Academy of Natural Sciences in Philadelphia, the University of Chicago and Harvard University. Although the team has amassed a diverse assemblage of fossil fish, Shubin said, the discovery of these transitional fossils in 2004 was a vindication of their persistence.
The scientists asked the Nunavut people to propose a formal scientific name for the new species. The Elders Council of Nunavut, the Inuit Qaujimajatuqangit, suggested "Tiktaalik" (tic-TAH-lick)--the word in the Inuktikuk language for "a large, shallow water fish."
The scientists worked through the Department of Culture, Language, Elders and Youth in Nunavut to collaborate with the local Inuit communities. All fossils are the property of the people of Nunavut and will be returned to Canada after they are studied.
The team depended on the maps of the Geological Survey of Canada. The researchers received permits from the Department of Culture, Language, Elders and Youth of the Government of Nunavut, and logistical support in the form of helicopters and bush planes from Polar Continental Shelf Project of Natural Resources Canada. The National Science Foundation and the National Geographic Society, along with an anonymous donor, also helped fund the project.
More recently, we have observed that God does "play dice" with the universe, and throws them where even He can't see them.
It's not static, and we can only know an approximation of what happens over long periods of time by observing what's going on now, but even that has a large degree of uncertainty.
Gnosticism assumed we could "know", with certainty, everything ~ particularly God's will (or even the will of the gods).
Being a Christian and not a Gnostic means rejecting gnosticism.
LOL!!
It tasted just like the gator tails at Razzoo's.
Objective reality is independent of the observer. I know of no observer who can be wholly independent of himself and his emotions. Consesnsus does not establish objective reality and is not an effective logical argument.
All that's needed to knock down that argument is to find a single Intelligent Designer who has managed to create only one marginally different lifeform.
ADM qualifies as the Intelligent Designer.
They aren't the only one either, but they exist and do that stuff.
So, cranking that into your dichotomy forces us to believe that ID is correct, or that Occam is wrong.
No doubt you didn't anticipate Occam being at stake in the debate or you wouldn't have done that, but you really have to keep in mind that in an everchanging Universe, with recombinant DNA technology being used and under further development, we cannot fail to INCLUDE the existence of at least one ID in the pot.
I think you have a better argument focusing on those "on" and "off" switches. There has to have been some high order data processing going on to come up with that one.
Thanks for the ping!
Because you made a Gnostic argument.
Gnostics believe there to be an objective reality. Non-Gnostics discover "truth" in a far different manner.
"Which gave rise to the Speculasaurus: father of all modern fishies and especially the Large-Mouth Grouper."
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To: blowfish
I think most Christians are becoming used to being insulted. But if the worst someone can call Christians is Bible-thumpers, then I can't complain too much. To: PatrickHenry
Just as Darwin said.............. 618 posted on 04/06/2006 7:20:26 AM CDT by stanz (Those who don't believe in evolution should go jump off the flat edge of the Earth.)
To: jec41
Again, another reader simply doesn't .....
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"By further reflecting that the clearest evidence would be requisite to make any sane man believe in the miracles by which Christianity is supported,—and that the more we know of the fixed laws of nature the more incredible do miracles become,—that the men at that time were ignorant and credulous to a degree almost incomprehensible by us,—that the Gospels cannot be proven to have been written simultaneously with the events,—that they differ in many important details, far too important, as it seemed to me to be admitted as the usual inaccuracies of eye witnesses;—by such reflections as these, which I give not as having the least novelty or value, but as they influenced me, I gradually came to disbelieve in Christianity as a divine revelation. The fact that many fake religions have spread over large portions of the earth like wildfire had some weight with me. But I was very unwilling to give up my belief; I feel sure of this, for I can remember often and often inventing day-dreams of old letters between distinguished Romans, and manuscripts being discovered at Pompeii or elsewhere, which confirmed in the most striking manner all that was written in the Gospels. But I found it more and more difficult, with free scope given to my imagination, to invent evidence which would suffice to convince me. Thus disbelief crept over me at a very slow rate, but was at last complete. The rate was so slow that I felt no distress, and have never since doubted even for a single second that my conclusion was correct."
( Charles Darwin in his Autobiography of Charles Darwin, Dover Publications, 1992, p. 62. )
Charles Darwin (1809-1882)
"I think that generally (& more & more as I grow older), but not always, that an agnostic would be the most correct description of my state of mind."
( Quoted from Adrian Desmond and James Moore, Darwin: The Life of a Tormented Evolutionist, New York: W. W. Norton & Company, 1991, p. 636. )
But....
What about believeing in a bunch of writings from BronzeAge goat-headers?
Don't THAT want to make you go cry and eat worms??
You are ignoring my question entirely. How do you measure complexity or information content? Everything is single celled for at least part of its life cycle, and amoebas have a longer genome than humans.
If ID folks are going to be consistent in placing information theory at the top of the chain of reasoning, then be consistent.
Tell us how to measure information, and tell us how an amoeba less complex than a human.
Agnostics are religious moderates. Can't make up their minds.
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