Evolution

Possible Link Between Fish and Land Animals Discovered

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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.html

Scientists 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 Replies to “Possible Link Between Fish and Land Animals Discovered

  1. 1
    DaveScot says:

    Looks like a big mudpuppy to me. 🙄

    This is evolutionary biology at its finest though. Sort of like stamp collecting.

    The practical benefit from this “great discovery” is exactly zero. Again like stamp collecting.

  2. 2
    DaveScot says:

    I take it back. A practical benefit occurred to me.

    As long as these ebola boys are playing with fossil skeletons they aren’t communicating their dreams of exterminating the human race to innocent young minds.

    I guess every cloud DOES have a silver lining.

  3. 3
    Lucks says:

    Davescot, i think you’re missing the point of science. Science is about discovery and learning. Engineering is about practical solutions 🙄

    Discovery and learning of things with no possible practical benefit isn’t science. It’s a hobby. Sort of like stamp collecting. Do it on your own nickel. Taxpayers have higher priorities. -ds

  4. 4
    tb says:

    Muuuhhahahahaha Hope they’ll find some more so they keep busy for a while!

  5. 5
    Jack Krebs says:

    Dave, I though you accepted commonn descent. I guess I don’t understand your scorn.

    Hi, Jack! *waves really fast. I have a more pressing question: Can you demonstrate how this fossil and the record in general support the gradualistic model of unguided evolution via NS + RM? –Scott

  6. 6
    pjburnhill says:

    The designer does have a great sence of humor, look at that Tiktaalik!

    …and an approach to engineering and design which is dizzying to our tiny little homo sapien brains, to say the least. Mercy! –Scott

  7. 7
    Scott says:

    ummmm… “like Archaeopteryx, the famous fossil that bridged the gap between reptiles and birds”.

    How recent is this article??? Evidently they didn’t get the memo on the “mosaic” called Mr. Archaeopteryx.

    *sigh… get your facts straight, people.

  8. 8
    samohth says:

    The article says;
    “Tiktaalik – the name means “a large, shallow-water fish” in the Inuit language”

    I listened to NPR on my drive home from work. They reported the Inuit word means “fish”.

    The part about learning to breathe air in a gradual process is the part that always comfounds me. Either the creature at some point could breathe both in and out of the water (which come to think of it would be a great survival advantage) or else at some point one solitary Tiktaalik “learned” to breathe air and then, how is that an advantage since it would be against most of the the creatures survival instincts. It would not only have to learn to breathe air but it would also have to learn how to use breathing air to an advantage, ISTM. I’m just asking. Maybe there is a good explanation for this.

  9. 9
    carbon14atom says:

    Yep, was gonna make a similiar comment as Scott, I was under the impression that true birds actually predate the archaeopteryx (type that word five times fast I dare ya, whew…)

  10. 10
    carbon14atom says:

    say, now that I think about it, description given sounds a awful lot like the description I was once given for the primitive “proto” salamanders…if this is correct, (big if) then this is not a “newly discovered” fossil at all would it be?

  11. 11
    Scott says:

    Sorry, I linked the wrong “memo”. Fixed now. 😉

  12. 12
    carbon14atom says:

    just got done reading the article behind Mr archaeo….
    updating my edu, I did not know the info contained therein…Thanks Scott…

  13. 13
    bFast says:

    I note two things. I thought that all of the missing links had been found, seems that there was a missing link now that a fossil has been found. Second, it is nice to notice that these guys are aware of the Intelligent Design movement. They don’t seem to understand the movement, but they seem to know that it exists. After all, most of us IDers do hold to common descent.

  14. 14
    apollo230 says:

    Tiktaalik is a wonderful find-I do congratulate the discoverers. It appears to substantiate the concepts of common ancestry and descent with modification, which to me are substantiated concepts backed by a wealth of evidence.

    However, the common sense that went into making the case for common ancestry did NOT go into the Darwinist effort to prove random variation/natural selection. While the common ancestry thesis is a triumph for evolutionary theory, the random variation proposal is properly seen as a logical embarrasment by comparison.

    Tiktaalik was crafted by something with an intellect – and a sense of humor!

  15. 15
    Lurker says:

    I’m about to reveal my ignorance on this matter so a little grace please.

    From what I’ve read, there are several ways to classify a species so its place in the ‘tree of life’ will depend on what method is used. Are there not species today, and in the past, that could easily be placed in a different part of the tree if another method is used?

    I guess my question is this: how do they know this is a transitional form and not a separate species that deserves its own unique branch?

  16. 16
    morpheusfaith says:

    “I guess my question is this: how do they know this is a transitional form and not a separate species that deserves its own unique branch?”

    Reply: Or better yet, convergence is so dominant in the fossil record that one could easily attribute the supposed “transitional” characters of this find as deriving independently from a common ancestor.

  17. 17
    kathy says:

    Guess that makes a platypus a link between ducks and otters.

  18. 18
    jaredl says:

    So… what about lungfish? What are they, chopped liver?

  19. 19
  20. 20
    GilDodgen says:

    Keep in mind that it is impossible to establish verifiable ancestor/descendent relationships for creatures that lived tens or hundreds of millions of years ago. Heck, it’s hard to establish ancestor/descendent relationships for humans who only lived a few hundred years ago, even with written records.

    So, this creature could be a transitional or it could be just another interesting creature with features in common with some other creatures. There is no way to know, so it’s all ultimately futile speculation.

  21. 21
    rpf_ID says:

    Lurker wrote: “I’m about to reveal my ignorance on this matter so a little grace please.

    From what I’ve read, there are several ways to classify a species so its place in the ‘tree of life’ will depend on what method is used. Are there not species today, and in the past, that could easily be placed in a different part of the tree if another method is used?

    I guess my question is this: how do they know this is a transitional form and not a separate species that deserves its own unique branch?”

    Wow, a person searching for answers who realizes their limited knowledge while seeking more in a most humble way. I say we need more like Lurker. Less dogma and more knowledge.

    Ricardo

  22. 22
    ajl says:

    What does this actually say about the claim that the Cambrian brought about all these new species, and then abruptly stopped?

  23. 23
    johnnyb says:

    As a non-common-ancestry person, let me ask a fundamental question:

    * what two _specific_ species is this a transition between

    A lot of supposed “transitionals” differ in significant detail from what proceeds before and after, and are only “transitional” in one or two areas. This is usually washed over with the idea that there was a common ancestor that was _really_ the transitional, and this is merely a close side-branch. But you can only do that so often.

    (of course, without soft body parts, we are missing most of the anatomy anyway, so any supposed transition is at most not very well supported, simply because there is not much anatomy to compare anyway)

  24. 24
    mentok says:

    They have discovered a new species and are calling it proof of evolution even though it proves exactly nothing other then that species existed. In order for “transitional fossils” to prove evolution there would have to be a bunch of them showing the creatures mutations. Without showing actual mutations born from a parent species then any claim that any fossil is a “transitional” fossil is really just speculative and not evidence for evolution.

    Since neo-darwinsim claims that evolution works through mutation the only way to prove evolution is to show those fossils which show a clear line of mutations from one species to the next. Actual creatures with mutations from the parent species, like a series of frog fossils showing wings gradually developing through mutations, not fully formed fully functional creatures like the species they just found which is without any visible mutation from a parent species. Without that all of their claims are just more smoke and mirrors for half baked charlatans mindlessly drifting aboard a ship of fools.

    Discovery of new extinct species… just for perspective there are an estimated 10+ million living species and only 1 in 10 of these have been identified. Moreover it’s estimated that living species account for only 1% of all species that ever lived. Finding rocks with imprints of heretofore unidentified ostensible transition species should be happening on a daily basis. The fact that it happens rarely and is huge news when it does happen doesn’t tend to support the generally accepted theory of evolution. Darwin was honest enough to admit this but his successors today evidently lack such candor. -ds

  25. 25
    Lurker says:

    “Wow, a person searching for answers who realizes their limited knowledge while seeking more in a most humble way. I say we need more like Lurker. Less dogma and more knowledge.”

    I suppose some of the evolutionists that read my question will write me off as some ‘dumb creationist hick’ who doesn’t get it.

    To me their explanation of the fossil record is not satisfying. I can see that they might be right, but I also see that they might be wrong – very wrong. When someone says science has determined that ‘goo-to-zoo-to-you evolution’ is true the skeptical hairs on my head stand straight up.

    They show me the fossil record and say “look, it’s true” and it changes nothing because I don’t necessarily accept their naturalistic assumptions. I accept all the biological facts and it changes nothing because, again, I don’t necessarily accept their naturalistic assumptions. I don’t need to be an evolutionary biologist to understand this stuff because *I accept all the facts as truth* – not their assumptions though. The facts do not show that creature A can transition into creature B over time via RM+NS alone. It’s their *assumptions* that make it true and I’m not ready to buy into that yet – probably ever. What’s a dumb hick like me to do?

  26. 26
    Scott says:

    Don’t forget though, Dave… they all (conveniently) avoided dying in the right strata for fossilization to occur.

    That one is my favorite.

  27. 27
    rpf_ID says:

    What’s a dumb hick like me to do?- Lurker

    Well for starters you could just bow at the Darwinians feet and give up…. OK or not….. However, that is what they would like us to do.

  28. 28
    BarryA says:

    DS

    “Finding rocks with imprints of heretofore unidentified ostensible transition species should be happening on a daily basis. The fact that it happens rarely and is huge news when it does happen doesn’t tend to support the generally accepted theory of evolution.”

    This really is the bottom line isn’t it. Thank you for your clarity!

  29. 29
    BarryA says:

    Scott

    “Don’t forget though, Dave… they all (conveniently) avoided dying in the right strata for fossilization to occur.”

    I am so disappointed in you Scott. Have you forgotten the tremendous debt we owe to the mystic philosopher/paleontologist Saint Stephen of Gould? Saint Stephen’s ground breaking, nay epoch shattering, insights gave us the dogma of punctuated equilibrium. We now know beyond the slightest doubt whatsoever that all of the transitional species crawled off and died in a place where their remains will never be found – probably because they all had a contrary nature. And it is in these holes in the fossil record that all of the evidence for Darwinist gradualism resides. You gotta have faith my friend, and for your transgressions against the one true faith I demand that you do ten “Hail Stephens” as penance.

  30. 30
    kvwells says:

    I still wonder, though. How does a non-rational animal simultaneously evolve the specifically arranged neurons in its brain (programming it to use the lungs, spinnerets, wings, eat meat, stick its tongue down an anthill, etc.) SIMULTANEOUSLY with the evolution of the novel organ. NS says use it or lose it. Ya cain’t use what ya don’t know ya got!

    Aren’t we talking about several thousand (at least) ‘lines’ of genetic code regarding the neural activity which controls the instinctive behaviors as well as the reflexes for the newbie organ? These must be in place BEFORE the novel structure can be used for anything but fishbait. I have not seen this issue of NS’ ability to teach (imprint extremely specified information in such a way that it can be recalled or used when needed) what it is about to evolve.

    Not to belabor this, but a ‘small’ organ or systematic difference in a higher organism can require a completely novel set of behaviors that cannot be learned by the organism. If DM through NS happens it must happen (and we must account for it) in the brain first.

  31. 31
    Scott says:

    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.

  32. 32
    BarryA says:

    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.

  33. 33
    Joseph says:

    “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

  34. 34
    Scott says:

    kvwells, good point.

  35. 35
    Michaels7 says:

    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 birds”. 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.

  36. 36
    rabbite_uk says:

    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).

  37. 37
    Michaels7 says:

    RabbiteUK, well, well…. if you cheack back, this is goodnews. I’ll have to check out Peter Hitchens.

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