Possible Link Between Fish and Land Animals Discovered
| April 6, 2006 | Posted by crandaddy under Evolution |
Discovered: the missing link that solves a mystery of evolution
Alok Jha, science correspondent
Thursday April 6, 2006
The Guardian
http://www.guardian.co.uk/frontpage/story/0,,1748005,00.htmlScientists have made one of the most important fossil finds in history: a missing link between fish and land animals, showing how creatures first walked out of the water and on to dry land more than 375m years ago.
Palaeontologists have said that the find, a crocodile-like animal called the Tiktaalik roseae and described today in the journal Nature, could become an icon of evolution in action – like Archaeopteryx, the famous fossil that bridged the gap between reptiles and birds.As such, it will be a blow to proponents of intelligent design, who claim that the many gaps in the fossil record show evidence of some higher power.
Richard Dawkins, the evolutionary biologist, said: “Our emergence on to the land is one of the more significant rites of passage in our evolutionary history, and Tiktaalik is an important link in the story.”
Tiktaalik – the name means “a large, shallow-water fish” in the Inuit language Inuktikuk – shows that the evolution of animals from living in water to living on land happened gradually, with fish first living in shallow water.
The animal lived in the Devonian era lasting from 417m to 354m years ago, and had a skull, neck, and ribs similar to early limbed animals (known as tetrapods), as well as a more primitive jaw, fins, and scales akin to fish.
The scientists who discovered it say the animal was a predator with sharp teeth, a crocodile-like head, and a body that grew up to 2.75 metres (9ft) long.
“It’s very important for a number of reasons, one of which is simply the fact that it’s so well-preserved and complete,” said Jennifer Clack, a paleontologist at Cambridge University and author of an accompanying article in Nature.
Scientists have previously been able to trace the transition of fish into limbed animals only crudely over the millions of years they anticipate the process took place. They suspected that an animal which bridged the gap between fish and land-based tetrapods must have existed – but, until now, there had been scant evidence of one.
“Tiktaalik blurs the boundary between fish and land-living animal both in terms of its anatomy and its way of life,” said Neil Shubin, a biologist at the University of Chicago, and a leader of the expedition which found Tiktaalik.
The near-pristine fossil was found on Ellesmere Island, Canada, which is 600 miles from the north pole in the Arctic Circle.
Scientists from the Academy of Natural Sciences in Philadelphia, the University of Chicago, and Harvard University led several expeditions into the inhospitable icy desert to search for the fossils.
The find is the first complete evidence of an animal that was on the verge of the transition from water to land. “The find is a dream come true,” said Ted Daeschler of the Academy of Natural Sciences.
“We knew that the rocks on Ellesmere Island offered a glimpse into the right time period and were formed in the right kinds of environments to provide the potential for finding fossils documenting this important evolutionary transition.”
When Tiktaalik lived, the Canadian Arctic region was part of a land mass which straddled the equator. Like the Amazon basin today, it had a subtropical climate and the animal lived in small streams. The skeleton indicates that it could support its body under the force of gravity.
Farish Jenkins, an evolutionary biologist at Harvard University said: “This represents a critical early phase in the evolution of all limbed animals, including humans – albeit a very ancient step.” Tiktaalik also gives biologists a new understanding of how fins turned into limbs. Its fin contains 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,” Professor 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.”
Dr Clack said that, judging from the fossil, the first evolutionary transition from sea to land probably involved learning how to breathe air. “Tiktaalik has lost a series of bones that, in fishes, covers the gill region and helps to operate the gill-breathing mechanism,” she said. “The air-breathing mechanism it had would have been elaborated and having lost the series of bones that lies between the head and the shoulder girdle means it’s got a neck, it can raise its head more easily in order to gulp the air.
“The flexible robust limbs appear to be connected with pushing the head out of the water to breathe the air.”
H Richard Lane, director of sedimentary geology and palaeobiology at the US National Science Foundation, said: “These exciting discoveries are providing fossil Rosetta stones for a deeper understanding of this evolutionary milestone – fish to land-roaming tetrapods.”
A cast of the fossil goes on display at the Science Museum in South Kensington central London today.
I feel that I should address the claim that this find is “a blow to proponents of intelligent design”. ID does not preclude evolution per se; it challenges the notion that evolution happened by blind chance. When somebody comes up with a plausible step-by-step model of how the mechanisms of the modern evolutionary synthesis could have created this (or any) transitionary form, then we can legitimately talk about blows to ID. Furthermore, when ID proponents speak of the sudden emergence of biological novelty, they tend to focus on the Cambrian explosion, during which many different animal body plans appear to originate suddenly over the span of only about 12 million years. This transition is believed to have occurred during the Devonian period which began about 75 million years after the Cambrian period had ended.
Despite the false claim that this fossil is a blow to ID, it is an interesting find. It may, in fact, be a transitionary form bridging fish and land animals. Perhaps it could help elucidate our understanding of the the relationship between fish and land animals and possibly the evolution of the former to the latter.
Update: Evolution News & Views has also picked up on this story, and Bill’s take on this find is pretty much the same as mine. I especially like Crowther’s last sentence which I present in its original form (bold type included): “There’s a problem with the Darwinist position that runs even deeper than this, however: If Darwinian evolution is an undisputed fact, as its chief defenders routinely claim, why is this fossil find being billed as such an crucial piece of evidence?”
Icing on the cake! I love it!!!
37 Responses to Possible Link Between Fish and Land Animals Discovered
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GAH! What was I thinking!? I was reading from the sacred book of 1st Opinions when I should have been meditating upon the book of II Hezitationz.
Scott,
You are forgiven. We are all tempted to stray. I, myself, have felt the lure of the “IDemons,” forever tempting me with their sirens’ song of logic and evidence.
“Some defenders of Darwinism embrace standards of evidence for evolution that as scientists they would never accept in other circumstances.” Henry Schaeffer, director of the Center for Computational Quantum Chemistry at the Univ. of Georgia (pg 41 of “Traipising into Evolution”)
I can’t wait for the “just-so” story of the selection pressure that had this puppy leave the water for land. It used to be that smaller fish left the water to escape being eaten and to find other food sources- which meant other organisms had to “evolve” out of the water and onto land before them.
Mentok said:
They have discovered a new species and are calling it proof of evolution even though it proves exactly nothing other then that species existed.
Mentok, I luv u man
kvwells, good point.
Good skeptical comments by all. In the past, when I took the blue pill, this news would be accepted as truth. Skeptical now I consider sources and sponsors of science.
The Guardian article is humorous re: ID. A new target acknowledged, struck at by blunt arrows. I hope DI responds re: ID. Guardian’s past foozling of ID causes skepticism on my part. They are more gatekeepers with an agenda than guardians of open information. Much like Science and Nature, they do not allow opposing opinions or findings to be reviewed prior to their announcements or if they do, it is inaccurate or misplaced. No opposing viewpoints, just lavish praise from the disciples of neo-Darwinian Church.
Scott’s #7 post “like Archaeopteryx, the famous fossil that bridged the gap between reptiles and birdsâ€Â. shed’s light on McEvo’s wishful thinking. Dr. Feduccia(an ornithologist, evolutionist and honest skeptic) soundly refutes false claims even recently by McEvo’s. It exposes how science with fawning media can mislead the public.
An apt quote from the Dr’s UNC website, “Feduccia said the publication and promotion of feathered dinosaurs by the popular press and by prestigious journals and magazines, including National Geographic, Nature and Science, have made it difficult for opposing views to get a proper hearing.”
Quoted from NG’s daily news:
“The National Geographic Society partially funded the project, which is to be detailed tomorrow in the journal Nature.”
So, we have a known promoter of evolution funding a ‘study’ for McEvo scientist. I realize this is routinely done. But, its like allowing Merck to both fund and report new drug findings without oversight by the FDA. Paying millions, of course its Macro-Evolution! And opposition may not examine closely the evidence.
Is there any other scientific field that works the way paleontology does today? Magazines with biased views fund pre-ordained scientist to support their findings?
Re: ID, the Guardian is biased(certainly on ID), or uninformed, and does not check facts. The Popular Press(National Geographic) – Sponsors themselves cannot act as Independent Media, nor can Nature their buddies suffice. The Guardian without critical skeptics cannot furnish any real rebuttals.
With a priori positions and without question, Media colludes(knowingly or ignorantly) with scientist that promote rhythmic drum beats to the sheep, giving credance to, “Any thought that is passed on to the subconscious often enough and convincingly enough is finally accepted.” A sales trick.
Sales and marketing leaders know intimately how repitition thru media influences our lives works. Those who skeptically take a considered and thoughtful long look, see the biased, unchecked promotion for what it is. Those who do not look closely become like sheep before a mechanized shepherd – ‘scientist said it, so it must be true’. Yet again, another fallacy repeated by secular press that distribute by rapid fire, their brummagem messages to an unsuspecting public at large.
Dr. Feduccia goes on to say, “With the advent of ‘feathered dinosaurs,’ we are truly witnessing the beginnings of the meltdown of the field of paleontology,” he said. “Just as the discovery a four-chambered heart in a dinosaur described in 2000 in an article in Science turned out to be an artifact, feathered dinosaurs too have become part of the fantasia of this field. Much of this is part of the delusional fantasy of the world of dinosaurs, the wishful hope that one can finally study dinosaurs at the backyard bird feeder.”
After much individual research on multiple articles, reviewing pro-evo sites I can only agree with Dr. Feduccia. There is a Disney element of fantasia to all story tellers in the McEvo business.
In an article on the fallacy of links between dinosaurs and birds out of China: http://www.exn.ca/dinosaurs/st.....es(another excellent point of evidence against McEvo), Dr Feduccia rightly points out time lines – bird/dinosaur evidence to the contrary. Most of what is said in popular science magazines are more about bravado than science.
Another article from NYT, posted here: http://faculty.plattsburgh.edu.....(excellent research), whereby Dr. Feduccia again agrees with the researchers on solid evidence against McEvo’s fallacy. Paleontology’s fundamentalist zeal for all things McEvo without factual evidence is appallingly exposed for what it is – wishful thinking.
Another apropo comment from Dr. Feduccia,
“Because the bird-dinosaur connection is so sexy, Feduccia says, “I feel like I’m taking candy away from some kid, but I’m confident that it’s not correct so I have to keep fighting the battle.”
That is an evolutionist’s honest view of just one segment of the current state of affairs in McEvo’s distorted worldview, which left unchecked, morph into their own self-glorification and fantasy. A battle indeed, among top scientist not associated with ID is ongoing under the cover. And while Feduccia still believes in McEvo, he is honest about current state of affairs in Popular Press and Scientific study in his field of study.
Joseph, I liked your point about small fish waddling on land first. That is exactly how it was related in my Biology book years ago. Small. Today, 9ft alligator/fish waddle out. And like you and others notice. What is the mechanism that forced such a beast out of water for survival? Why? There is no conceivable scientific reason, only ‘Fantasy’. We know that fish, whales, turtles all migrate in the sea between warm and cold climates. Yet they want us to believe this one decided to come on land. It is absurd the false logic being put forth here in my opinion by sponsors with nefarious reasons.
I have a question for McEevo’s, National Geographic sponsors, Nature, Science. Will they allow top scientist who are skeptics to review all the data, up close? Perform their own test and then report to the public their findings? This is what happens in all other areas of science. Why not Paleontology?
But wait, maybe not all areas of science. Dr. Behe is treated with scorn by neo-Darwinians. Without an opportunity of original work on IC by Dr. Behe in Science, now a paper appears in Science attempting to refute IC and thus ID. Yet they never allowed Dr. Behe the equivalent academic peer-reviewd treatment.
So, they put forth questionable evidence against ID while not allowing the original proponents same access? How cowardly is that? Honestly, is that not what cowards do? They denounce their opponents sharply without allowing them rebuttals? Thus running from confrontation of the evidence before them?
I am seriously doubting the objectivity of Popular Science magazines today, and even the peer-reviewed papers, their editors and scientist in this area of paleontology and the extended ongoing controversy of ID.
Not all of the press are biased towards Darwinist dogma, even though it sometimes seems that way. In today’s Mail on Sunday newspaper in the UK, the columnist Peter Hitchens writes an excellent piece, “If Darwin fanatics are right, where’s my fins?”:
“Darwinist fundamentalists this week produced a fishy fossil which, they claimed, was evidence of their weird and increasingly shaky theory.”
“From these bones, they claimed to have deduced that large fish spent hundreds of thousands of years developing shoulders (why would a fish want shoulders? To do press-ups on the beach? How would I develop fins if I wished to reverse the process?) plus a lot of other contentious, vague, circular waffle.”
“Should these people be allowed to propagate their bizarre creed in schools? Should children be exposed to fanatical atheism and unprovable claims dressed up as if they were proper science?”
“I respect the sincerity of their faith in the idea that nature happened by accident, but surely it is better suited for discussion in religious education classes?”
Peter Hitchens also some months back wrote a 2-page article in the same paper promoting ID. He is my favourite columnist and we should be thankful that there are still journalists like him around to air such views (and be allowed to of course).
RabbiteUK, well, well…. if you cheack back, this is goodnews. I’ll have to check out Peter Hitchens.