Leader Bee Posted June 6, 2010 Posted June 6, 2010 OK it's a dumb question... because they have gills! But aren't those gills just extracting oxygen from the water already? I would have personally thought that even though water may be more oxygen rich (being hydrogen and 2 oxygen atoms after all) that air would have been easier to extract the oxygen from as it's already freely floating around and therfore no need to seperate the 02 from something I'm no biology expert so I thought i'd better ask this burning question on SFN before I forgot I was curious about it.
Moontanman Posted June 6, 2010 Posted June 6, 2010 OK it's a dumb question... because they have gills! But aren't those gills just extracting oxygen from the water already? I would have personally thought that even though water may be more oxygen rich (being hydrogen and 2 oxygen atoms after all) that air would have been easier to extract the oxygen from as it's already freely floating around and therfore no need to seperate the 02 from something I'm no biology expert so I thought i'd better ask this burning question on SFN before I forgot I was curious about it. The main reason is that the fishes gill filaments need to be supported by water to expose all of their surface area. Out of the water the gill filaments collapse on each other and the surface area is greatly diminished, much like a mammals lungs collapsing.
Double K Posted June 7, 2010 Posted June 7, 2010 There are some fish that breathe air... Lungfish Breathing A distinctive characteristic of the Queensland lungfish is the presence of a lung-like swim bladder. Modified into a vascularized air-breathing organ, it is used to supplement the oxygen supply through the gills.[2] During times of excessive activity, times of drought or high temperatures (when water becomes deoxygenated), or when prevailing conditions inhibit normal functioning of the gills, the lungfish can rise to the surface and swallow air into its lung.[4] It has been shown that more frequent air breathing is correlated with periods of greater activity at night when it uses the lung as a supplementary organ of respiration.[12] The lung is a single long sac situated above and extending the length of the body cavity, and is formed by a ventral outgrowth of the gut. Internally, the lung is divided into compartments by the infolding of the walls. Each compartment is further divided to form a spongy alveolar region. Blood capillaries run through this region close enough to the air space in the lung to enable gas exchange. Lungfish breath in using a buccal force-pump similar to that of amphibians. The contraction of smooth muscles in the walls of the lung results in exhalation.[13] The sound of the lungfish exhaling air at the surface prior to inhaling a fresh breath has been compared to that made by a small bellows.[2] Young lungfish come to the surface to breathe air when they are about 25 mm long.[6] http://en.wikipedia.org/wiki/Queensland_lungfish and Mudskippers The ability to breathe through their skin and the lining of their mouth (the mucosa) and throat (the pharynx). This is only possible when the mudskipper is wet, limiting mudskippers to humid habitats and requiring that they keep themselves moist. This mode of breathing, similar to that employed by amphibians, is known as cutaneous air breathing.[4] Another important adaptation that aids breathing while out of water are their enlarged gill chambers, where they retain a bubble of air. These large gill chambers close tightly when the fish is above water, keeping the gills moist, and allowing them to function. They act like a scuba diver's cylinders, and supply oxygen for respiration also while on land.[4] http://en.wikipedia.org/wiki/Mudskipper
Mr Skeptic Posted June 7, 2010 Posted June 7, 2010 In addition to what Moontanman said, the fish's ventilation system may not work with air. Also, air actually has a lot more oxygen than water, for breathing purposes. The oxygen in H2O is essentially unusable, for animals at least. There is roughly 30 times as much oxygen in air as in water (depends on temperature and other conditions), and on top of that, the water is 1000 times more dense and 1000 times more viscous. Also gases diffuse much more quickly in air than in water.
hobz Posted June 7, 2010 Posted June 7, 2010 In practice if you keep the gills wet, the fish will be able to survive above water, breathing air.
Moontanman Posted June 7, 2010 Posted June 7, 2010 In practice if you keep the gills wet, the fish will be able to survive above water, breathing air. Um no, only a few fish that have evolved a mechanism to allow them to survive for short times with wet gills can do that, many catfish come to mind, the average fish cannot survive out of water for long due to the effects of the difference between water and air as i stated in an earlier post. Some fish die with in a few tens of seconds of being removed from the water, others like some catfish can survive long periods of time out of the water via gulping air into their intestines, some have a special organ inside their gill cavities, others can actually use their swim bladder like a lung. But your basic fish cannot breath air unless the oxygen is dissolved in water...
jimmydasaint Posted June 7, 2010 Posted June 7, 2010 Great topic, but I have to digress. I remembered reading about an artificial gill that was like a box with membrane wrapped around it to allow oxygen to flow into the chamber containing the human. So the real advantage was that humans would not need sophisticated diving equipment to stay underwater but could meet their oxygen needs from the surrounding water. I found it fascinating that the guy who was interested in this equipment put his dog at the bottom of his pond in such a device - and it survived happily - if a bit bemused. I thought I would never find a scientific paper actually reflecting this story yet here we are: An Artificial Gill System for Oxygen Uptake from Water Using PerfluorooctylbromideHaramoio, Hiroiaka; Kokubo, Kin-Ichi; Sakai, Kiyotaka; Kuwana, Katsuyuki; Nakanishi, Hikaru Abstract If the oxygen dissolved in seawater could be used for breathing, human beings could spend more time under water, greatly increasing their mobility. As yet, however, sufficient oxygen to enable us to live in the sea for long periods is not available. An artificial gill system has been developed for oxygen uptake from water to deoxygenated air using perfluorooctylbromide (PFOB), which has high oxygen solubility. It was found that oxygen was transferred rapidly from water to PFOB when water flowed outside the hollow fibers and PFOB flowed inside. Oxygen transfer through the membrane from PFOB to air was found to be the rate determining step. Use of PFOB gave a stable supply of oxygen from water to deoxygenated air over long periods. It was found that PFOB acts as a storage medium for oxygen. Link to article
skyhook Posted June 8, 2010 Posted June 8, 2010 fish do breath surface air. Labyrinth fishes, bettas, gouramis ,snakeheads, climbing perch(Anabas testudineus),knife fish, swamp eel,.... Catfish have many species, those sucker-mouth catfish go to the water surface to take in air, and go down again. It might be adaptation to the water or environment, which are poorly oxygenated. Pools of still water, or water which just have low oxygen level due to decaying matter at the bottom. But sometimes, the conditions changed, like from dry season to wet season, and these fish can live in fast flowing streams to flooded plains too. I've kept some of these fish in aquarium before, and it seems while they can breath surface air, with aeration from air pump they may grow better. They can't survive long out of water. snakeheads, walking catfishes may be a few hours, once they dried up, they die too. They can survive longer if kept in water which is above their body, and can be crowded in a container for a while, as seen in some markets in some places in asia.
Leader Bee Posted June 8, 2010 Author Posted June 8, 2010 Great topic, but I have to digress. I remembered reading about an artificial gill that was like a box with membrane wrapped around it to allow oxygen to flow into the chamber containing the human. So the real advantage was that humans would not need sophisticated diving equipment to stay underwater but could meet their oxygen needs from the surrounding water. I found it fascinating that the guy who was interested in this equipment put his dog at the bottom of his pond in such a device - and it survived happily - if a bit bemused. I thought I would never find a scientific paper actually reflecting this story yet here we are: Link to article I believe i've seen a documentary on this before, the designer had plans for it to supply oxygen to a marine lab somewhere on the coast. I've found a link to this companies website explaining the technology: http://likeafish.biz/
Narroo Posted July 6, 2010 Posted July 6, 2010 Hmm. What happened to the Artificial Gill chamber? Sounds neat.
StrontiDog Posted July 9, 2010 Posted July 9, 2010 . . . .even though water may be more oxygen rich (being hydrogen and 2 oxygen atoms after all) . Just for clarification from the OP's basic premise. First of all, water (H2O) is TWO hydrogen atoms and ONE oxygen. Fish don't get their oxygen from the one in the water molecule. They need regular gaseous oxygen just like we breathe. This oxygen is dissolved in water, very much like the bubbles in a carbonated soft drink are carbon dioxide molecules that were also dissolved in water, before you popped the cap and released the pressure in the bottle. The OP seemed to be under the impression that some kind of electrolysis was where the oxygen came from, which could explain the initial confusion. Bill Wolfe
Asyncritus Posted August 12, 2010 Posted August 12, 2010 If all the above is more or less correct, then how did an aquatic, gill-breathing fish become an air-breathing tetrapod as is sometimes alleged?
jcarlson Posted August 17, 2010 Posted August 17, 2010 (edited) If all the above is more or less correct, then how did an aquatic, gill-breathing fish become an air-breathing tetrapod as is sometimes alleged? It has been mentioned several times in this thread that there are several types of ancient and extant fish that have the ability to breath air via a modified swim bladder. The organs used for breathing air and breathing water are completely unrelated. Some ancient fish with this ability evolved further tetrapodal traits and at one time there were many species similar to Tiktaalik which possessed characteristics of modern day fish and tetrapods. Some of these in turn evolved into the first amphibians; true tetrapods, though the young were born in water and retained the ability of their fish ancestors to breathe water via gils for a period after birth, just like most modern day amphibians. How is this not blantantly obvious to you? I'm highly suspicious you're being dishonest with either us intentionally or yourself unintentionally in order to keep the illusion of special creation alive in your brain. Edited August 17, 2010 by jcarlson 1
Ophiolite Posted August 17, 2010 Posted August 17, 2010 How is this not blantantly obvious to you? I'm highly suspicious you're being dishonest with either us intentionally or yourself unintentionally in order to keep the illusion of special creation alive in your brain. Nice one jcarlson: the perfect way to persuade a creationist as to the inaccuracy of their beliefs - simultaneously insult their intelligence and their integrity. Brilliant! For a follow up why don't you tell us, without consulting any reference books, or internet sites, did the swim bladder evolve from the lung, or did the lung evolve from the swim bladder. I'm sure you are aware the answer is blatantly obvious. (Although it is curious how long it took biologists to work it out. Do you suppose they were being dishonest?)
Asyncritus Posted August 17, 2010 Posted August 17, 2010 (edited) It has been mentioned several times in this thread that there are several types of ancient and extant fish that have the ability to breath air via a modified swim bladder. If the fish are extant, that simply proves that they have not evolved, and are in no way ancestors of lung breathing animals. So that fails to help your case. Incidentally, fossil lungfish, extraordinarily like the modern ones have been found nearly a couple of hundred million years old. The organs used for breathing air and breathing water are completely unrelated. How true! If they are 'completely unrelated', then they did not descend from water breathing structures. There's no relationship. Some ancient fish with this ability evolved further tetrapodal traits and at one time there were many species similar to Tiktaalik which possessed characteristics of modern day fish and tetrapods. Some of these in turn evolved into the first amphibians; true tetrapods, though the young were born in water and retained the ability of their fish ancestors to breathe water via gils for a period after birth, just like most modern day amphibians. You obviously haven't heard about the wreckage wrought on the Tiktaalik theory! They found tetrapod tracks some 18 million years older than Tiktaalik. Some ancestry there! (The report is in Nature, Jan 2010). How is this not blantantly obvious to you? I'm highly suspicious you're being dishonest with either us intentionally or yourself unintentionally in order to keep the illusion of special creation alive in your brain. You are the one making the blatantly obvious statements. You said they are 'completely unrelated', and you're right. It must be obvious to anyone with a minimum of biological knowledge that a gill and a lung have precious little to do with one another. A gill needs submergence - a lung is the diametric opposite. A lung breather can hold its breath underwater, a gill breather actually breathes underwater. A gill breather dies out of water. A lungbreather is designed to breathe out of water. The instinctive requirements of gill breathing and lung breathing are entirely different, and there is no possible transition between the two things. Instincts, being immaterial, cannot be and are not subject to the normal evolutionary mechanisms. Edited August 17, 2010 by Asyncritus
Moontanman Posted August 17, 2010 Posted August 17, 2010 If the fish are extant, that simply proves that they have not evolved, and are in no way ancestors of lung breathing animals. So that fails to help your case. Incidentally, fossil lungfish, extraordinarily like the modern ones have been found nearly a couple of hundred million years old. You fail to make a point with this... How true! If they are 'completely unrelated', then they did not descend from water breathing structures. There's no relationship. Again what is your point? You obviously haven't heard about the wreckage wrought on the Tiktaalik theory! They found tetrapod tracks some 18 million years older than Tiktaalik. Some ancestry there! (The report is in Nature, Jan 2010). Your point please? You are the one making the blatantly obvious statements. You said they are 'completely unrelated', and you're right. It must be obvious to anyone with a minimum of biological knowledge that a gill and a lung have precious little to do with one another. A gill needs submergence - a lung is the diametric opposite. A lung breather can hold its breath underwater, a gill breather actually breathes underwater. Still no point.... A gill breather dies out of water. A lungbreather is designed to breathe out of water. Other than the idea of designed you are correct... The instinctive requirements of gill breathing and lung breathing are entirely different, and there is no possible transition between the two things. Instincts, being immaterial, cannot be and are not subject to the normal evolutionary mechanisms. Can you back up that assertion? What about an animal that has both structures? There are fish that have both structures, as well as amphibians, not to mention turtles that breath through their anus.... I can back my claims... can you?
Asyncritus Posted August 18, 2010 Posted August 18, 2010 You fail to make a point with this...Your vocabulary seems somewhat restricted, so I'll do my best not to confuse you If X exists today, then it can't be the ANCESTOR of Y. That simple enough for you? Again what is your point? If X is COMPLETELY UNRELATED to Y, then X cannot be the ANCESTOR of Y. That is the definition of UNRELATED. Therefore fish cannot be the ancestors of lung breathers. Your point please? Tiktaalik is not a 'transitional' between fish and tetrapods which are lungbreathers. Other than the idea of designed you are correct... Can you back up that assertion? What about an animal that has both structures? There are fish that have both structures, as well as amphibians, not to mention turtles that breath through their anus.... I can back my claims... can you? My 'claim' about instinct is hardly a claim. It must be obvious to all lung breathers that it is a basic fact. Here's X with gills. Zap. It becomes, all of a sudden Y with lungs. Does it know what to do with the lungs? Should it stay in or get out of the water? What's this diaphragm thing anyway? Those are questions Y has to KNOW the answer to - or it's dead, because it will keep sticking its head under water (since it thinks its a fish) and drown. Therefore, since there's nothing round there to teach it what to do with lungs, the instinct was implanted complete and entire. But that's a creationist statement. There's lots more like it here: www.howdoesinstinctevolve.com. Perhaps you'd like to have a look. The author claims that it is the most ruinous argument against evolution ever posed.
Moontanman Posted August 18, 2010 Posted August 18, 2010 (edited) Your vocabulary seems somewhat restricted, so I'll do my best not to confuse you If X exists today, then it can't be the ANCESTOR of Y. That simple enough for you? It's quite simple, not to mention totally wrong.... you are about as confusing as tic tac toe and about as predictable... And I have the center square... If X is COMPLETELY UNRELATED to Y, then X cannot be the ANCESTOR of Y. That is the definition of UNRELATED. Therefore fish cannot be the ancestors of lung breathers. Again you show a profound ignorence of both biology and evolution not to mention a total lack of problem solving skills, you really don't have a clue do you? Tiktaalik is not a 'transitional' between fish and tetrapods which are lungbreathers. Please show your evidence of this assertion... or more to the point why is that a problem for fish evolving into amphibians? My 'claim' about instinct is hardly a claim. It must be obvious to all lung breathers that it is a basic fact. Here's X with gills. Zap. Zap? "More Bounce to the ounce?" Nothing goes Zap, WTF do you mean ZAP? magical thinking does not apply to science.... It becomes, all of a sudden Y with lungs. Again you show that you are really drinking the koolaid, do you dance and shout while you handle rattle snakes too? Does it know what to do with the lungs? Should it stay in or get out of the water? What's this diaphragm thing anyway? Diaphragms came much later, this has no bearing on the problem what so ever... Those are questions Y has to KNOW the answer to - or it's dead, because it will keep sticking its head under water (since it thinks its a fish) and drown. Bullshit begets more bullshit yet again.... Therefore, since there's nothing round there to teach it what to do with lungs, the instinct was implanted complete and entire. But that's a creationist statement. There's lots more like it here: www.howdoesinstinctevolve.com. Perhaps you'd like to have a look. The author claims that it is the most ruinous argument against evolution ever posed. I really don't know whether I should laugh histerically or cry, why are you here? oh wait, my troll detector is glowing brightly in the deep violet YEC=DKNSFS Edited August 18, 2010 by Moontanman
Ophiolite Posted August 18, 2010 Posted August 18, 2010 Your vocabulary seems somewhat restricted, so I'll do my best not to confuse you If X exists today, then it can't be the ANCESTOR of Y. That simple enough for you? The post addressing extant fish did not claim that the extant fish were ancestors of anything. The point being made was that some fish, today and in the past, have demonstrated an abilty to breathe air. It is therefore entirely plausible that one such ancient fish could have further evolved to become fully airbreathing. In short your argument here was an attack on a strawman.
Ringer Posted August 18, 2010 Posted August 18, 2010 Your vocabulary seems somewhat restricted, so I'll do my best not to confuse you If X exists today, then it can't be the ANCESTOR of Y. That simple enough for you? X may not be the ancestor of Y but that doesn't rule out a common ancestor of X and Y If X is COMPLETELY UNRELATED to Y, then X cannot be the ANCESTOR of Y. That is the definition of UNRELATED. Therefore fish cannot be the ancestors of lung breathers. You show a harsh misunderstanding of evolution Tiktaalik is not a 'transitional' between fish and tetrapods which are lungbreathers. Transitional is a bad word to use in this, it assumes an end point that isn't there. All animals at all times are transitional animals. Also, there are "fish" that can breath air now, that doesn't make the evolution of water to air any less valid. Fish is also a blanket word to describe a wide variety of species. Salmon are more akin to humans than sharks. My 'claim' about instinct is hardly a claim. It must be obvious to all lung breathers that it is a basic fact. Here's X with gills. Zap. It becomes, all of a sudden Y with lungs. Does it know what to do with the lungs? Should it stay in or get out of the water? What's this diaphragm thing anyway? Those are questions Y has to KNOW the answer to - or it's dead, because it will keep sticking its head under water (since it thinks its a fish) and drown. Again, you show a deep seeded misunderstanding of evolution. is a video that might help you. Also, knowledge and instinct are two totally different things, but I won't get into that. I can almost guarantee that the majority of people really don't know how breathing works and they still do it all the time. Therefore, since there's nothing round there to teach it what to do with lungs, the instinct was implanted complete and entire. But that's a creationist statement. There's lots more like it here: www.howdoesinstinctevolve.com. Perhaps you'd like to have a look. The author claims that it is the most ruinous argument against evolution ever posed. Instinct isn't taught, that's why it's instinct. Where you taught what pain felt like or how to breath. No, you just do. And if that book gave a ruinous argument against evolution I would think that it would be found somewhere else besides that website. I can't find the author's name anywhere, could you give the name so I can see credentials.
Mr Skeptic Posted August 18, 2010 Posted August 18, 2010 Asyncritus, the claim is that lungs are homologous to swim bladders. Your argument that lungs are not homologous to gills is entirely misdirected (though true).
Asyncritus Posted August 19, 2010 Posted August 19, 2010 The post addressing extant fish did not claim that the extant fish were ancestors of anything. The point being made was that some fish, today and in the past, have demonstrated an abilty to breathe air. It is therefore entirely plausible that one such ancient fish could have further evolved to become fully airbreathing. In short your argument here was an attack on a strawman. Lungfish are extant. Lung breathers are everywhere. Therefore lungfish cannot be ancestors of lungbreathers: and in any case, the 'lungs' of lungfish are completely unrelated and dissimilar to what we would call proper 'lungs'. They are devoid of the complex structures (such as bronchioles and alveoli) which make up the average lung. It is therefore NOT entirely plausible that a lungfish could 'evolve' into a lung breather. If they did, then they would not be here any longer. X may not be the ancestor of Y but that doesn't rule out a common ancestor of X and Y These hypothetical common ancestors simply do not exist. If they do, then where are they? I don't wish to derail this debate, but would like to ask where the 'common ancestors' of the zillion or so species in the Cambrian are. Not to mention the 'common ancestors' of the cyanobacteria in the preCambrian. Transitional is a bad word to use in this, it assumes an end point that isn't there. All animals at all times are transitional animals. Also, there are "fish" that can breath air now, that doesn't make the evolution of water to air any less valid. Fish is also a blanket word to describe a wide variety of species. Salmon are more akin to humans than sharks. You remind me of Gould's statement that if evolution is indeed taking place, then there ought not to be anything like species. Since there are about a billion or so species, all clearly described and properly classified, with many thousands more waiting in the wings from the palaeontologists, then your statement is less than accurate. Again, you show a deep seeded misunderstanding of evolution. is a video that might help you. Also, knowledge and instinct are two totally different things, but I won't get into that. I can almost guarantee that the majority of people really don't know how breathing works and they still do it all the time. The argument presented in 'How Does Instinct Evolve?' is an extremely basic one. It acknowledges your point that instinct is untaught, and presents many examples of behaviours which have catastrophic consequences for evolution, which can offer no explanations of how such behaviours may have arisen. They are untaught, and are yet demonstrably present in many creatures which perform unbelievable feats: of navigation, for example. However, the book makes an undiscovered or unmentioned point which you touch on in the next paragraph, and which is totally ruinous to evolution, and which has never been addressed anywhere. Instinct isn't taught, that's why it's instinct. Where you taught what pain felt like or how to breath. No, you just do. And if that book gave a ruinous argument against evolution I would think that it would be found somewhere else besides that website. I can't find the author's name anywhere, could you give the name so I can see credentials. You are perfectly correct, but have you realised that you have singlehandedly just ruined the whole theory? Where did the information/ instinct powering breathing come from? Without it, the very first organism was dead before it started. I will leave you to answer that one.
Ophiolite Posted August 19, 2010 Posted August 19, 2010 Your observations here display a deep misunderstanding of evolution. Lungfish are extant. Lung breathers are everywhere. Therefore lungfish cannot be ancestors of lungbreathers: and in any case, the 'lungs' of lungfish are completely unrelated and dissimilar to what we would call proper 'lungs'. They are devoid of the complex structures (such as bronchioles and alveoli) which make up the average lung. It is therefore NOT entirely plausible that a lungfish could 'evolve' into a lung breather. If they did, then they would not be here any longer. The lungfish that are alive today are descendants of lungfish that were alive in the past. It is entirely possible for some of the ancestors of ancient lungfish to have given rise to the land vertebrates. At the same time other lungfish would have been the ancestors of today's lungfish. What do you find so implausible about this? Are you aware that we have examples today of speciation in vertebrates of just this sort of thing. The whole point about evolution is that small changes occur and build over time. There are other types of fish which breathe in oxygen through there stomach walls. The lungfish takes that approach a stage further. Build on the very simple structures present in the lungfish's lung over millions of years and you readily develop a fully fledged lung with as many bronchial passages and alveoli as you could wish for. And to repeat, there is absolutely no reason a population of lungfish, separate into different environments, should not evolve in separate ways. Please note that the lungfishes that are extant today are not the same as the lungfishes alive in the distant past. They may have many morphological similarities, but they will be genetically distinct. If we had a time machine and could retrieve one of those ancestral lungfished it is probable that it could not interbreed with today's lungfish. In order to better understanf how you have arrived at these distorted ideas of evolution would you summarise what education (formal, or self) you have in this field? That might better equip me to address yout points in a helpful manner.
Moontanman Posted August 19, 2010 Posted August 19, 2010 (edited) Lungfish are extant. This makes no sense what so ever.... BTW there are several different species of lungfish but you have already stated you do not believe species mean anything... Lung breathers are everywhere. There are lots of fish too, again you make no point what so ever... Therefore lungfish cannot be ancestors of lungbreathers: and in any case, the 'lungs' of lungfish are completely unrelated and dissimilar to what we would call proper 'lungs'. They are devoid of the complex structures (such as bronchioles and alveoli) which make up the average lung. The lung fish alive today are obviously not ancestors of anything, you are assuming things that have no real basis in reality and lungs did not spring into existence with the complex structures you seem to demand, ZAP! is not part of evolution... It is therefore NOT entirely plausible that a lungfish could 'evolve' into a lung breather. If they did, then they would not be here any longer. This is totally false, it is entirely possible for a group of animals to split off from the main group and become a new species over time with both species still living but as i said you have already asserted that you don't believe in species. A stingray is a stingray.... is your own words and is totally false.... These hypothetical common ancestors simply do not exist. If they do, then where are they? I don't wish to derail this debate, but would like to ask where the 'common ancestors' of the zillion or so species in the Cambrian are. Not to mention the 'common ancestors' of the cyanobacteria in the preCambrian. Why would you say this, what makes you believe such tripe? You remind me of Gould's statement that if evolution is indeed taking place, then there ought not to be anything like species. Since there are about a billion or so species, all clearly described and properly classified, with many thousands more waiting in the wings from the palaeontologists, then your statement is less than accurate. This is taken completely out of context, species is an artifact of human design that allows us to keep track of different animals, all species are just the latest version of that animal. The argument presented in 'How Does Instinct Evolve?' is an extremely basic one. It acknowledges your point that instinct is untaught, and presents many examples of behaviours which have catastrophic consequences for evolution, which can offer no explanations of how such behaviours may have arisen. They are untaught, and are yet demonstrably present in many creatures which perform unbelievable feats: of navigation, for example. No, instinct has evolved with animals that exhibit certain behaviors surviving and the ones who do not not surviving, the instinct is part of the natural behaviors of the animal it does not have to be learned or thought about. However, the book makes an undiscovered or unmentioned point which you touch on in the next paragraph, and which is totally ruinous to evolution, and which has never been addressed anywhere. Only in the minds of people who desperately need to believe in something that is a total lie. You are perfectly correct, but have you realised that you have singlehandedly just ruined the whole theory? Where did the information/ instinct powering breathing come from? Without it, the very first organism was dead before it started. I will leave you to answer that one. No, no animal sprung up with lungs from an animal with no lungs, behaviors/instincts evolved along with the animals as they needed them. The tendency to gasp for air evolved from the natural tendency of fish to try and breath while out of water. I don't see any point in trying to explain this but primitive fish gulp air to neutralize their buoyancy, this is where swim bladders and eventually lungs came from the instinct to gulp air came before lungs not after. Evolution usually occurs from modifying adaptations or behaviors that already exist for another purpose. YEC=DNKSFS Edited August 19, 2010 by Moontanman
Ringer Posted August 19, 2010 Posted August 19, 2010 Lungfish are extant. Lung breathers are everywhere. Therefore lungfish cannot be ancestors of lungbreathers: and in any case, the 'lungs' of lungfish are completely unrelated and dissimilar to what we would call proper 'lungs'. They are devoid of the complex structures (such as bronchioles and alveoli) which make up the average lung. It is therefore NOT entirely plausible that a lungfish could 'evolve' into a lung breather. If they did, then they would not be here any longer. Their lungs are extremely similar to ours. There has been quite a bit of research on how lungs evolved, even between birds and dinosaurs. These hypothetical common ancestors simply do not exist. If they do, then where are they? I don't wish to derail this debate, but would like to ask where the 'common ancestors' of the zillion or so species in the Cambrian are. Not to mention the 'common ancestors' of the cyanobacteria in the preCambrian. You must not realize how lucky we are to have fossils to help us. But even without them common descent is a fairly solid theory. You remind me of Gould's statement that if evolution is indeed taking place, then there ought not to be anything like species. Since there are about a billion or so species, all clearly described and properly classified, with many thousands more waiting in the wings from the palaeontologists, then your statement is less than accurate. Species are animals that can interbreed to produce fertile offspring, if there were no species there would be no life. Other classifications are somewhat arbitrary in nature but are still useful for our purposes of understanding plant and animal life. Like my statement about fish earlier, it still allows us to classify and that's what it's there for. The argument presented in 'How Does Instinct Evolve?' is an extremely basic one. It acknowledges your point that instinct is untaught, and presents many examples of behaviours which have catastrophic consequences for evolution, which can offer no explanations of how such behaviours may have arisen. They are untaught, and are yet demonstrably present in many creatures which perform unbelievable feats: of navigation, for example. However, the book makes an undiscovered or unmentioned point which you touch on in the next paragraph, and which is totally ruinous to evolution, and which has never been addressed anywhere. Have you ever read anything of evolution of instinct. I'd post more links but I think this post has enough already. You are perfectly correct, but have you realised that you have singlehandedly just ruined the whole theory? Where did the information/ instinct powering breathing come from? Without it, the very first organism was dead before it started. I will leave you to answer that one. My previous post still stands. The gulping of air is normal for most fish to create buoyancy, it's not a stretch to use the same thing to start breathing. An easier way to thing about it, If you're dying from suffocation you will do anything to try to breath, the ones who figure it out live and breed, those who don't die and don't reproduce. <-- vast oversimplification but hey.
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