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Have we discovered how fish first learned to walk on land?

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Not really.

From Britain’s Daily Telegraph

Scientists at McGill University have discovered that fish change their anatomy and learn to walk more efficiently when kept out of water for a prolonged period in a discovery that hints at how ancient species evolved to walk on land.

The researchers kept polypterus, an African fish with lungs, on land for eight months (they would normally gravitate back to water).

In less than a year, they found that the fish had learned to walk more efficiently, placing their fins closer to their bodies and lifting their heads higher. They had also learned to move without slipping.

Even their skeletons had adapted around the shoulders, becoming stronger and elongated to increase support during walking and deal with the loss of support from the water.

“There were anatomical changes that resembled the same key evolutionary changes that are seen in the tetrapods that moved into land.”

From Nature:

After 8 months, the terrestrially raised bichir [polypterus] had a more sophisticated style of walking than did aquatically raised controls. Furthermore, their bone structure and musculature changed to be more suited to a walking lifestyle.

The results provide evidence for developmental plasticity, in which organisms alter their anatomy and behaviour in response to environmental change. The team suggests that this process, as demonstrated by the bichir, could have given the earliest tetrapod ancestors the ability to venture onto land. In doing so, claims Standen, they would have become exposed to the selective pressures of a terrestrial environment, thereby speeding up the evolutionary transformation from fins for swimming into limbs for walking.

Maybe. But if they are that plastic, wouldn’t they just go back to the water, given a chance?

David A. DeWitt, biology and chemistry chair at Liberty University, writes to say,

This is not evolution! It has absolutely nothing to do with evolution. There is nothing that is heritable here:

“After 8 months, the terrestrially raised bichir had a more sophisticated style of walking than did aquatically raised controls. Furthermore, their bone structure and musculature changed to be more suited to a walking lifestyle.

The results provide evidence for developmental plasticity, in which organisms alter their anatomy and behaviour in response to environmental change. The team suggests that this process, as demonstrated by the bichir, could have given the earliest tetrapod ancestors the ability to venture onto land. In doing so, claims Standen, they would have become exposed to the selective pressures of a terrestrial environment, thereby speeding up the evolutionary transformation from fins for swimming into limbs for walking.”

They are not talking about natural selection, they are talking about behavioral plasticity. This is a fancy way of saying ‘learned behavior’. The fish that were raised in a terrestrial environment improved their walking ability. Also, although they say that the “organisms alter their anatomy and behavior” it would be more accurate to say that “their behavior altered their anatomy.” This is not the way that we usually think about such things, but that is what happens. The fish did not will themselves to have different anatomy. However, as they used certain muscles in particular ways, those muscles grew stronger. As the muscles grew stronger, they put different mechanical pressures on the bones. The shape of the bones were altered in response to the different mechanical pressures.

See, people intuitively (and falsely) believe that bones are not malleable, that they take a particular shape and that is it. Were it so, we would not be able to grow. The fact is that bone cells continually turn over, but less so as we age. Mechanical pressure will significantly alter how the bone cells divide and therefore over time will alter the shape. Anyone who wears glasses has a way to prove it. Where the frame of the glasses make contact with the skull behind the ears there will be slight depressions. When you get a different pair of glasses, it won’t exactly match, but over time the location of the depression will move.

Here is another example: Babies are born flat footed. As they begin to walk, the arch of the foot develops. The shape of the bones and the way the muscles connect alters in response to the forces and pressures of upright walking. This happens automatically and it is because of how the bone cells respond to mechanical pressure. There is not a gene that produces an arched foot, it is a developmental response to behavior.

Notice what they did not do: they did not select for fish that walked better. The individual fish themselves improved in their walking ability through learning and as they used muscles repeatedly in different ways those muscles grew stronger and as a result, there were changes in bone morphology. No natural selection here. How long did it take? Less than 1 generation.

Standen assumes that natural selection in fact favoured such fish back in the Devonian. We don’t know for sure unless we have some idea what the advantage might be. One problem is that she must have fed and protected the fish during the course of the experiment, something nature is markedly less likely to do. Also, what about egg laying? A fish that could not get back to water, could not lay eggs, and either the line would die out or the plasticity would reverse itself.

What this experiment mainly shows is how fish can become more terrestrial without any evolution, provided they cannot get back to the water. But could they feed and protect themselves on land indefinitely back then? This particular fish has markedly failed to abandon the water, left to itself.  Interesting experiment, for sure.

See also: Early tetrapod (“fishapod”) sheds light on transition to land— maybe (Tiktaalik)

and

Have we at last solved the question of how sea creatures moved to land? (Pacific leaping blenny, which also never really abandoned the water)

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Comments
velikovskys wrote
The problem is any changes which occurred in a terrestrial environment might put them at a disadvantage on the return to the water, where fins are more efficient. They may be lunch.
Ah, but after pretending to turn back into fish for a while, some would survive and then evolve into humans who would later return to land. :P -QQuerius
September 3, 2014
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tiguy, How would you ever test that? I guess you might start by studying what food sources were available on the land, fossils might provide evidence of diet. Contrast structural differences between the marine and terrestrial versions. All you have to do is think up a “plausible sounding explanation” and you are good to go. You could create a blog or a non profit institute to help the explanation along,but in science they collect stuff called data, a good explanation should explain new data as well as existing data, if it doesn't the explanation is revised or replaced. logic, I would like to see them continue this expirement by letting the fish go back into the water and watch how the fish go back to normal. The problem is any changes which occurred in a terrestrial environment might put them at a disadvantage on the return to the water, where fins are more efficient. They may be lunch.velikovskys
August 31, 2014
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logically_speaking,
...letting the fish go back into the water and watch how the fish go back to normal.
Once again proving evolution. lol That's pretty much what happens with peppered moths and Darwin's finches. But notice that Darwinist descriptions are usually anthropomorphic and Lamarckian. -QQuerius
August 31, 2014
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So these scientists are using tax payers money to discover what we already know, namely that bones and muscles change in accordance with certain pressures and usage. Awesome! I'm always amazed but never suprised at how evolutionists try to call anything and everything evolution even when it is clearly nothing of the sort. I would like to see them continue this expirement by letting the fish go back into the water and watch how the fish go back to normal.logically_speaking
August 31, 2014
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Vel says:
news, Maybe. But if they are that plastic, wouldn’t they just go back to the water, given a chance?
Less competition for food?
Maybe. Maybe not. How would you ever test that?! This is the problem with evolutionary theory. It's not testable. All you have to do is think up a "plausible sounding explanation" and you are good to go.tjguy
August 31, 2014
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As to the fossil evidence, a few years ago Darwinists were very excited that Tiktaalik seemed to finally provide a 'missing link' for the evolution of fish to a land dwelling creature, but, as is usual with Darwinian hype, their excitement soon turned to disappointment,,,
“Darwinians have long looked for missing links between sea animals and land animals to fulfill one of the major predictions of Darwinism. Neil Shubin went on an expedition to an area where he thought it might be likely to find such a fossil and miraculously discovered Tiktaalik which seemed a perfect fit for the prediction. That does count as a confirmation of the prediction, although with more evidence, it has now become an extremely weak one, counting for little if anything now. Why? For several reasons. 1) Many researchers have pointed out that the Tiktaalik has numerous aspects in common with fish. It's pelvis is also fishy, and this is crucial. Neil Shubin himself (the discoverer of Tiktaalik who wrote the book 'Your Inner Fish), has now admitted that Tiktaalik has a fish pelvis (and all other features are fishy) and does not not have a sacral rib connecting the pelvic girdle to the vertebral column (which is crucial to enable tetrapods to walk and bear their weight on land). Shubin tries to finagle some way that Tiktaalik could walk on land using a totally fishy pelvis, but the reality is that Tiktaalik was and always will be a fish that cannot walk based on all the objective scientific evidence we have, unless Darwin's ghost has somehow made it possible for tetrapods without sacral bones to magically walk now. Tiktaalik has now joined the ranks of many debunked Darwinian fossils that litter the history of Darwinism. It's just a fish people, a unique fish designed by its Creator, but nothing more. It provides no support for Darwinism.” http://creation.com/tiktaalik-pelvis
Moreover,,
Tiktaalik Blown "Out of the Water" by Earlier Tetrapod Fossil Footprints - January 2010 Excerpt: The tracks predate the oldest tetrapod skeletal remains by 18 Myr and, more surprisingly, the earliest elpistostegalian fishes by about 10 Myr. http://www.evolutionnews.org/2010/01/tiktaalik_blown_out_of_the_wat.html
This following article has a excellent summary of the 'less than forthright' (i.e. heavy handed) manner in which Darwinists handled anyone who dared question this paltry evidence:
Evolutionary Biologists Are Unaware of Their Own Arguments: Reappraising Nature's Prized "Gem," Tiktaalik - Casey Luskin - September 2010 http://www.evolutionnews.org/2010/09/evolutionary_biologists_are_un038261.html
The discontinuity in the fossil record is far sharper than many people realize:
Fish & Dinosaur Evolution vs. The Actual Fossil Evidence - video and notes http://vimeo.com/30932397 Romer's Gap fossils have not provided transitional forms (for hypothetical fish to land animal) - David Tyler - March 2012 Excerpt: All the fossil evidence shows discontinuity, but evolutionary linkages are marked (all located within Romer's Gap) that are devoid of supporting data. We are still a long way from a science that majors "on the presence, rather than the absence, of fossil data". http://www.arn.org/blogs/index.php/literature/2012/03/20/romer_s_gap_fossils_have_not_provided_tr
supplemental note: As to the inflated hype of Darwinists for any supposed transitional fossil, followed by the inevitable let down, Darwinists have a long, infamous, history in that regards, especially as it pertains to supposed human evolution:
Hominid Hype and the Election Cycle - Casey Luskin - September 2011 Excerpt: Ignoring fraudulent fossils like Piltdown man, the last 50 years have seen a slew of so-called human ancestors which initially produced hype, and were later disproven. http://www.evolutionnews.org/2011/09/hominid_hype_and_the_election_050801.html Has Science Shown That We Evolved from Ape-like Creatures? by Casey Luskin - Fall 2013 (useful references at the end of the article) Excerpt: A closer look at the literature shows that hominin fossils generally fall into one of two categories—ape-like species or human-like species (of the genus Homo)—and that there is a large, unbridged gap between them. Despite the claims of many evolutionary paleoanthropologists, the fragmented hominin fossil record does not document the evolution of humans from ape-like precursors. In fact, scientists are quite sharply divided over who or what our human ancestors even were. Newly discovered fossils are often initially presented to the public with great enthusiasm and fanfare, but once cooler heads prevail, their status as human evolutionary ancestors is invariably called into question. - http://salvomag.com/new/articles/salvo26-science-faith/has-science-shown-that-we-evolved-from-ape-like-creatures.php What Questions About Evolution Come Down to Is, "Who ARE We?" - Denyse O'Leary - August 18, 2014 Excerpt: ,,, "human evolution" is now so integral to our culture that demand outpaces authenticity. The disappointing history of Sahelanthropus, Orrorin, and Ardi, all hailed in 2001 as human ancestors, attests to the frustrating search for "missing links." Sediba, another supposed ancestor, fared no better in 2013. A science writer at Wired, not known for intelligent-design sympathies, derides the ceaseless buzz as "ancestor worship.",,, "Flores Man" is an example. Supposedly, a new diminutive species of humans (discovered in 2004) arose, flourished, and died out from earlier than 18,000 years ago,,, The latest article I'm aware of charges that "Homo floresiensis" is an invalid species classification, and the principal skeleton may have been of a woman who suffered from a genetic disorder, Down syndrome. It hardly sounds like settled science to an observer.,,, http://www.evolutionnews.org/2014/08/what_questions089051.html “What I saw about the fossil record again,, was that Gould and Eldridge were experts in the area where the animal fossil record is most complete. That is marine invertebrates.,, And the reason for this is that when,, a bird, or a human, or an ape, or a wolf, or whatever, dies,, normally it does not get fossilized. It decays in the open, or is eaten by scavengers. Things get fossilized when they get covered over quickly with sediments so that they are protected from this natural destructive process. So if you want to be a fossil, the way to go about it is to live in the shallow seas, where you get covered over by sediments when you die,,. Most of the animal fossils are of that kind and it is in that area where the fossil record is most complete. That there is a consistent pattern.,, I mean there is evolution in the sense of variation, just like the peppered moth example. Things do vary, but they vary within the type. The new types appear suddenly, fully formed, without an evolutionary history and then they stay fundamentally stable with (cyclical) variation after their sudden appearance, and stasis (according) to the empirical observations made by Gould and Eldridge. Well now you see, I was aware of a number of examples of where evolutionary intermediates were cited. This was brought up as soon as people began to make the connection and question the (Darwinian) profession about their theory in light of the controversy. But the examples of claimed evolutionary transitionals, oddly enough, come from the area of the fossil record where fossilization is rarest. Where it is least likely to happen.,,, One of things that amused me is that there are so many fossil candidates for human ancestorship, and so very few fossils that are candidates for the great apes.,, There should be just as many. But why not? Any economist can give you the answer to that. Human ancestors have a great American value and so they are produced at a much greater rate.,, These also were grounds to be suspicious of what was going on,,, ,,,if the problem is the greatest where the fossil record is most complete and if the confirming examples are found where fossils are rarest, that doesn’t sound like it could be the explanation." - Phillip Johnson - April 2012 - audio/video 15:05 minute mark to 19:15 minute mark http://www.youtube.com/watch?v=FJDlBvbPSMA&feature=player_detailpage#t=903s "A number of hominid crania are known from sites in eastern and southern Africa in the 400- to 200-thousand-year range, but none of them looks like a close antecedent of the anatomically distinctive Homo sapiens…Even allowing for the poor record we have of our close extinct kin, Homo sapiens appears as distinctive and unprecedented…there is certainly no evidence to support the notion that we gradually became who we inherently are over an extended period, in either the physical or the intellectual sense." Dr. Ian Tattersall: - paleoanthropologist - emeritus curator of the American Museum of Natural History - (Masters of the Planet, 2012)
bornagain77
August 30, 2014
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velikovskys,
Less competition for food?
There can indeed be competing priorities. Escape from preditors might be another reason. -QQuerius
August 30, 2014
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Axel noted
And the inspired, poetic treatment of such profound spiritual truth invests it with extraordinary power, doesn’t it?
That's what I find sometimes here and there, and always when I read the Bible. The wisdom of Lao Tsu had a similar effect on me early on:
The best [man] is like water. Water is good; it benefits all things and does not compete with them. It dwells in [lowly] places that all disdain. This is why it is so near to Tao.
A true and noble scientist is humble, always ready to be instructed by nature, God, and fellow humans regardless of their position. -QQuerius
August 30, 2014
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news, Maybe. But if they are that plastic, wouldn’t they just go back to the water, given a chance? Less competition for food?velikovskys
August 30, 2014
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I've sometimes mused that I stopped learning there and then. That poem contained all I needed or wanted to know. Whatever I learnt after that has been only what God wanted me to learn. That's mostly narcissistic twaddle, but there is, I think, a little kernel of truth in it.Axel
August 30, 2014
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Q, it's weird, but that made an immense impression on me as a young child, when my limited experience of the world and life could not have prepared me to understand the full meaning. I know the note of defiance of the donkey was special to me, in the light of his description of himself as what we, in our debased post-Christian world, are pleased to call 'a loser'. And the inspired, poetic treatment of such profound spiritual truth invests it with extraordinary power, doesn't it? In another connection, a Catholic, popular, historical novelist called Louis De Wohl, wrote a book on the life of St Thomas Aquinas, called he Quiet Light, and in it, he wrote that at the university he attended he was called by his fellow-students, the Dumb Ox, because he never volunteered an answer to lecturers' questions. One day, he was asked to do so, and gave a long magisterial disquistion in answer to the question he'd been asked, leaving everyone dumbfounded, not least the lecturer. He was a real oddball, (but not like Donald Sutherland's character), as his family were robber baron, Borgia types, but he'd been brought up from the age of five, as a Benedictine oblate - which did leave him somewhat simple-minded in some ways. For instance, when his fellow students mocked him for shuffling over to the window, after they had told him there was a donkey (there it is again) flying past it, he intoned, no doubt very solemnly, 'I had rather believe that a donkey could fly, than that a Dominican novice could tell a lie....' He makes George Washington sound positively racey, doesn't he? Jack the Lad.Axel
August 30, 2014
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Axel, Thanks, I've always admired the wit of Chesterton. There's a lot of symbolism hidden in "The Donkey" that I didn't understand, so here's what I found online http://www.theepochtimes.com/n2/arts-entertainment/the-antidote-a-reading-of-the-donkey-by-g-k-chesterton-327025.html Nice. -QQuerius
August 30, 2014
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Dr JDD, Exactly. And it is nonsense. The lungfish did indeed already have lungs as you noted, and as David DeWitt was previously quoted:
This is not evolution! It has absolutely nothing to do with evolution. There is nothing that is heritable here
I don't understand what's so hard to grasp here. What if this were a test question:
Which of the following is an example of evolution: a. African lungfish developing stronger limbs after spending more time out of water. b. Selective breeding that results in the chihuahua over the last 2,000 years or so. c. The appearance of chloroquine resistance in malaria. d. All of these.
Of course there are those here who would immediately choose d on the claim that evolution is "change over time." This would qualify nearly everything as evolution, including the regrettable degradation of the paint job on some areas on my car due to solar radiation, the digestion of the food that I had for lunch, the deforestation of the Amazon, and global warming. Oops, I mean climate change. Where are my manners? ;-) -QQuerius
August 30, 2014
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I mean the first verse, of course, in terms of the mythical evocation.Axel
August 30, 2014
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I prefer this mythical evocation by G K Chesterton. I've always loved it: 'When fishes flew and forests walked And figs grew upon thorn, Some moment when the moon was blood Then surely I was born. With monstrous head and sickening cry And ears like errant wings, The devil’s walking parody On all four-footed things. The tattered outlaw of the earth, Of ancient crooked will; Starve, scourge, deride me: I am dumb, I keep my secret still. Fools! For I also had my hour; One far fierce hour and sweet: There was a shout about my ears, And palms before my feet.'Axel
August 30, 2014
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It's just a shame that in the more technologically-advanced, modern societies of today, there is no longer any place for such wonderfully Byzantine, religious narratives. I believe that tens of thousands of years of an ascetical life-style forced on them by their environment, have made Australian Aborigines natural mystics, so little wonderment that their Creation narrative is extraordinarily rich and colourful. The puzzle is, how these atheists, at least to a limited extent, seem to short-circuit this multi-millennial process of religious development at the existential margins, and are able to produce such a fascinating religious mythology, almost as if 'on demand'.Axel
August 30, 2014
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Yeah, I read this the other day. Funny how it is about evolution yet they are taking wild type (i.e. genetically identical for all intents and purposes as those they keep in water) fish who already possess the ability to breath (have functional lungs) and seeing if they can adapt to living out of water, in the same generation. In other words, no evolution here guv'. Just plain old using what you have and adapting. No Darwinian processes, no random mutations conferring benefit. No, just clever fish, who already have lungs. Oh, and by the way, they already have lungs. It is a crime to science to even relate this in anyway to evolution or guessing how "easily" ancestors made the transition to land. THE ANCESTORS HAD TO EVOLVE FUNCTIONAL LUNGS FIRST. Simples? Unlikely. Oh, and by the way, these fish HAD FULLY FUNCTIONAL LUNGS ALREADY. It's like sticking some humans in the wild without civilisation and making comments on how humans evolved to their environment to find food with natural predators before they learned to make it into caves. Science is really sinking to a new low. This study is purely about how amazing a fish that usually lives in water (HAS FUNCTIONAL LUNGS), spends minimal time out of water given the choice, can actually survive out of water quite comfotably through adapting (and because it has functional lungs). That's all, nothing here about evolution. What would have been really interesting is to see if there were changes in the epigenetic inheritance of the offspring of these land adapted fish. (Oh and by the way, THEY ALREADY HAD LUNGS). ~ For it is written, "I WILL DESTROY THE WISDOM OF THE WISE, AND THE CLEVERNESS OF THE CLEVER I WILL SET ASIDE." ~ ...who foils the signs of false prophets and makes fools of diviners, who overthrows the learning of the wise and turns it into nonsense..Dr JDD
August 30, 2014
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