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.
A set of statements or principles devised to explain a group of facts or phenomena, especially one that has been repeatedly tested or is widely accepted and can be used to make predictions about natural phenomena.
The branch of a science or art consisting of its explanatory statements, accepted principles, and methods of analysis, as opposed to practice: a fine musician who had never studied theory.
A set of theorems that constitute a systematic view of a branch of mathematics.
Abstract reasoning; speculation: a decision based on experience rather than theory.
A belief or principle that guides action or assists comprehension or judgment: staked out the house on the theory that criminals usually return to the scene of the crime:
He means this definition:
An assumption based on limited information or knowledge; a conjecture.
" He means this definition:
An assumption based on limited information or knowledge; a conjecture. "
Yes, the last one. You don't get to pick and choose which definition to use; their uses have already been established. A scientific theory is:
"A set of statements or principles devised to explain a group of facts or phenomena, especially one that has been repeatedly tested or is widely accepted and can be used to make predictions about natural phenomena."
It is not "An assumption based on limited information or knowledge; a conjecture.".
Philosophy has most helpful in establishing faith and belief in moral and ethical concepts by argument. Few societies would exist without them. However one should not forget none are proved, absolute, or fact. Some societies fail because of their philosophy and its inability to change. Their (concepts) strength is that most of a society believes the philosophy. Philosophy provides little or no new knowledge and resists change of any faith and belief that has appeared to work in the past.
You cannot make a horse from a fish...
Nor can you get a human from an ape
But, if you catagorize evolution to the developement of adapting to the environment, hence the theory of the giraffe getting a longer neck to reach the leaves higher in the trees..(bunk theory, why haven't all leaf eating animals developed long necks for survival?)
Most evolutionists want to believe life came from one cell. Creationalist believe in all creation developed by design.
I personally do not care, Something still had to start the whole process somewhere. You can't get something from nothing. Only life can beget life.
" Philosophy has most helpful in establishing faith and belief in moral and ethical concepts by argument."
It has also been crucial in developing the rules of inquiry that we use in science, through the philosophy of epistemology. It's not just about faith and morality.
And I would not have necessarily called all of them slackers, maybe a few, but some are doing quite well now, even though they took a few "THEORY" classes for easy credit.
But nice try.....
Actually ID has provided facts, testable models, etc. But you've accepted the Darwin Fundie religion without question so you wouldn't know that, would you? Doesn't sound like you know what evolution or speciation is. Your cut & paste Darwin Fundie Talking Points don't impress me either. Only a Fundie would blindly listen to his leaders. Funny how people like you accuse other people of being pseudofundimental! Where'd you get that word? Public school? No wonder you think evolution is true.
Testable ID model (books with more science than any Darwin Fundie book):
Origins of Life
http://www.amazon.com/exec/obidos/tg/detail/-/1576833445/
Nobel Laureate, Richard Smalley said of "Origins": "Evolution has just been dealt its deathblow...it is clear evolution could not have occured."
Who was Adam?
http://www.amazon.com/exec/obidos/tg/detail/-/1576835774/
"The parallels that it proves between Genesis and the scientific data are profound." - Dr. John Bloom, physics professor, Biola University
The Creator and the Cosmos: How the Latest Scientific Discoveries of the Century Reveal God
http://www.amazon.com/exec/obidos/tg/detail/-/1576832880/
"A compelling summary of scientific evidence that supports the belief in God..." - Walter Bradley, head of Mech. Egr. Dept at A&M University.
"...clearly indicate[s] that the universe was created with many characteristics fine-tuned for life." - Dr. Kyle Cudworth, Yerkes Observatory
Not trying to convince anyone. Merely making a point.
True, you do not have to agree. But my faith in my belief, which is based on historical facts, sure beats trying to rest my soul on a premis that all things came from a primordal soup.
The people I "knew of" in college, I would not have been able to provide their motivations for taking classes. You have to be a bit closer to them to know why they are taking something. I could guess at their motivation, which is what I suspect you have done.
Anyway, you missed a great learning opportunity in an area where you thought nothing useful was to be gained. Music theory is a fascinating topic, having knowledge of why Mozart chose to voice a section of a sonata as he did is very enlightening. Seeing the independent lines of a Bach fugue, and understanding how it got put together is just damn interesting, IMHO.
I was just teasing you about the whole slacker thing anyway, no harm intended. Your negative comments about the study of music theory earned you that teasing.
"Obviously ~6.7 billion people observe it every day although you may be the exception"
Wow, are you speak for all 6.7 billion poeple?
"If there are any differences no matter how small then some change or evolution has occurred."
nonsense, evolution has not occurred. Traits have to exist within the gene pool to be passed down. non existent traits such as eyes didnt exist according to your theory so how were they passed down?
how the hell did you format that post that way?
um... it wasn't an assertion. please don't "speed over" what I write.
ID may be a philosophical premise, but philosophy has it's own methods for weeding out the well reasoned from the "not so much". If ID is based on irrational epistemology, metaphysical justice shall have it's way. I
Also, I was not guessing at some people's motivation for taking the class. It was widely known that for an easy A, one could take "Music Theory", Music Appreciation, Art Appreciation, etc....
However, all is well and I understand you point that to some people "Music Theory" is a great learning opportunity.
Music theory is an entirely different animal that art or music appreciation. In the appreciation classes, you look at or listen to, then discuss, and maybe write a paper or 2. Music theory requires one to actually compose sections of, or entire, pieces of music using the common era rules of voice leading, harmony and the like. Don't know where you went to school, but theory was no easy A, and I was highly motivated to learn the material (to this day, 25+ years after graduating from college, I still perform).
Okay, very well. It is not my opinion. I am only stating what "scientists" have observed.
(These same observations that can be obscured to speed processes, altered to fit a hypothesis and help push an agenda.)
Agreed! If we look at research from this perspective how can we believe any conclusions to be accurate?
Philosophy provides little or no new knowledge and resists change of any faith and belief that has appeared to work in the past.
Not neccessarily. If applied correctly, it can expose false premises, sometimes to the dismay of the philosopher.
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