Evolution of the cardiovascular system is impossible

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Re: Evolution of the cardiovascular system is impossible

Postby Christine Janis » Tue Aug 12, 2014 2:08 am

Frank gives the game away here. Nobody in science distinguishes between "origins" and operations" science.


Er --- "operatlonal science", surely? Frank can't even get the creationist lingo right.
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Re: Evolution of the cardiovascular system is impossible

Postby Roger Stanyard » Thu Aug 14, 2014 8:50 am

Christine Janis wrote:
Frank gives the game away here. Nobody in science distinguishes between "origins" and operations" science.


Er --- "operatlonal science", surely? Frank can't even get the creationist lingo right.


Few creationists have any serious knowledge of the "creation science" they promote and claim to beiieve in. Hence my simple, easy to answer, questions to Frank. Alas, he has run away.

"Operations science" is, of course, a branch of management science.
Those who believe absurdities will commit atrocities - Voltaire
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Re: Evolution of the cardiovascular system is impossible

Postby Frank » Sun Mar 01, 2015 5:27 am

Roger Stanyard wrote:What he actually wrote was ‘We should reject, as a matter of principle, the substitution of intelligent design for the dialogue of chance and necessity; we must concede that there are presently no detailed Darwinian accounts of the evolution of any biochemical or cellular system, only a variety of wishful speculations.’ (Franklin M. Harold,* 2001. The way of the cell: molecules, organisms and the order of life, Oxford University Press, New York, p. 205.)

Harold is not, of course, a proponent of Inelligent Design or creationism but you have selectively misquoted him to support your opinions on Intelligent Design.<snip>

I never claimed that Harold was a proponent of Intelligent Design. I stated that he was an evolutionist:
“But evolutionary theory fails to explain the origin of the cardiovascular system or any other body system. Evolutionist Franklin Harold admits:”

"...but we must concede that there are presently no detailed Darwinian accounts of the evolution of any biochemical or cellular system, only a variety of wishful speculations." (Franklin M. Harold, The way of the cell: molecules, organisms and the order of life, Oxford University Press, New York, p. 205, 2001).

So I was not quoting Harold out of context. The point of the quote from Harold was to show that even an evolutionist agrees with what ID proponents are claiming. So do you agree that the heart developed in this sequence: myocardium, valves, cardiac conduction, as Christine Janis does? The supposed evolution of the cardiovascular system is the topic here.
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Re: Evolution of the cardiovascular system is impossible

Postby Frank » Sun Mar 01, 2015 5:39 am

Christine Janis wrote:Fishes evolve a single system because the source of oxygen pick up is at the gills. Lungs are added *within the fish condition*, at which point a double circulatory system is acquired, one to the lungs and one to the gills.
Frank wrote:As usual, you are merely telling stories; your statement is devoid of any science.

How can I be "telling stories" when I am describing what is the condition in living animals. <snip>

You are telling stories (admitted by yourself earlier) because all you are doing is describing some anatomical differences, then waving the magic evolutionary ward for transformations. This is not science. Also, the dual CV system consists of a systemic circulation pumping blood to the body and a pulmonary circulation providing oxygen and carbon dioxide exchange with the respiratory system. This is part of my previous post that you have failed to respond to:

"So how did the coronary arteries and veins, which form a closed system for the heart, supposedly evolve?! Each coronary artery and vein in humans has three layers – tunica adventitia, tunica media and tunica intima, so remember to explain how these layers supposedly evolved. Neural innervation of the coronary vessels provides vasodialation, which needs to be explained as well. Of course the consequence of having limited blood flow to the coronary vessels (myocardial infarction) cannot be ignored."

I have updated my original post providing a summary of your failed attempt to provide an evolutionary explanation for the CV system.
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Re: Evolution of the cardiovascular system is impossible

Postby Frank » Sun Mar 01, 2015 5:51 am

So why did you respond to my post to a_haworthroberts when you have failed to even respond to most of my refutation of what you wrote previously?!
Christine Janis wrote:
Frank wrote:The six branches of the aorta in humans: brachiocephalic trunk, right subclavian artery, internal thoracic artery, vertebral artery, axillary artery and the brachial artery provide blood to the upper parts of the body including the arms and head. They are not “merely connecting pipes”, they are required for life. Also, the statement above assumes evolution to start with, which means the argument is circular reasoning.

Hello --- those "six branches" are not the same as the six original aortic arches.<snip>

Same old nonsense from Janis. Once again, this is known as the logical fallacy of circular reasoning. By saying “the six original aortic arches” you are assuming evolution to start with, which means your argument is circular. Understand?! Here is what you should have responded to:

"The sinoatrial node in the human heart is a group of autorhythmic cells that acts as the pacemaker of the heart. It is only a very small part of the human heart. The amphioxus “heart” has no valves, no separate chambers, no endocardium and no epicardium. Fluid is pumped by the pulsing of arteries. So much for the amphioxus “heart” being homologous with the human heart."

and this:

"Typical of evolutionists, you have failed completely to specify what is required for sympathetic innervation of the heart. Chemoreceptors monitor levels of oxygen and carbon dioxide in the arteries and brain respectively. This information is processed by the brain, and the heart rate is adjusted accordingly via innervation which consists of a preganglionic neuron, a ganglion and a postganglionic neuron. This clearly shows design by an intelligent agent. Your claim that phylogenetics shows the development of more complex systems is simplistic and amounts to nothing more than waving the magic evolutionary ward to produce more complex systems."

and this:

"The fallacy of your argument is assuming that similarities show evolutionary relationships. Dolphins have a similar body structure to sharks, however dolphins are mammals and sharks are fish, which are not related according to evolutionary theory. Also, if similarities supposedly show evolutionary relationships, then conversely non-similarities must show that animals are not related, such the large difference between the single circulation CV system of fish and the dual circulation CV system of mammals, birds, amphibians and reptiles."
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Re: Evolution of the cardiovascular system is impossible

Postby Frank » Sun Mar 01, 2015 6:06 am

Christine Janis wrote:"Hagfish don’t have a vertebral column, so are not vertebrates such as fish, amphibians, reptiles, birds and mammals. Hagfishes are likely the most primitive of the vertebrates, which is defined as animals included within the subphylum Vertebrata, which is diagnosed by a number of features, including the possession of a cranium, neural crest tissue in development, and a duplication of the number of Hox genes. Hagfishes have, however, recently been shown to possess rudiments of haemal arches of a vertebral column in the tail (much as the way that lampreys possess rudiments of neural arches). So even that objection of yours is defunct.
Frank wrote:"You have failed to show that hagfish have a vertebral column, so my argument stands. Claiming that “…rudiments of haemal arches of a vertebral column in the tail” is hardly a vertebral column. What shoddy rubbish you write. Besides, what you have written above is nothing but another red-herring."
Christine Janis wrote:Hmm, so Frank thinks that the definition of the subphylum Vertebrata is the presence of a vertebral column.<snip>

In your own words: “Hagfish don’t have a vertebral column, so are not vertebrates such as fish, amphibians, reptiles, birds and mammals.” This was your comment, not mine. What more do I need to say?! Here is what you should have responded to, which is related to the origin of the CV system:

"Also, you have provided absolutely no evolutionary explanation for the origin of red blood cells in lamphreys or hagfish. So in effect you have made the situation twice as impossible to answer as I described with the origin of the erythrocytes in the skeletal system."

and this:

"This must be the ultimate hand-waving argument. To state the obvious, you have failed to even mention the respiratory system that is found in vertebrates that is used for the ventilation and perfusion of oxygen and carbon dioxide. You have failed to explain (or even mention) how the respiratory system of mammals supposedly evolved. No mention of lungs, the bronchial tree, alveoli or breathing. Simply wave the magic evolutionary ward and these structures appear. But the magic evolutionary wand must be waved again to produce a diaphragm, because this is needed for breathing. Neural innervation of the diaphragm is required for the diaphragm to function, so the magic evolutionary wand must be waved again. But what is the problem for evolutionists?! After believing in countless absurd evolutionary scenarios, believing in a few more hardly makes any difference, does it?!"

and this:

"What completely ridiculous nonsense! For starters, you have started off with a lancelet which has a closed circulatory system with pulsing arteries. You have failed to provide an evolutionary explanation for this animal. So the magic evolutionary ward is waved and an atriam and ventricle and two heart valves supposedly evolved?! Heart valves work in conjunction to provide a one-way flow of blood through the circulatory system. So you are claiming that cardiac conduction evolved after heart valves supposedly evolved?! Without cardiac conduction, there will be no pumping of blood (even with valves) and death will occur; this is stating the obvious."
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Re: Evolution of the cardiovascular system is impossible

Postby Frank » Sun Mar 01, 2015 6:17 am

Christine Janis wrote:
Frank wrote:It is rather amusing that you need to resort to the discredited pseudoscience of Ernst Haeckel (“ontogeny recapitulates phylogeny”). You are totally confused between origins science and operations science in claiming that embryological development has anything to do with supposed evolutionary development. How an animal supposedly survived in its environment with a partially developed CV system is not addressed.

And I wonder what Frank means by a "partially developed CV system".<snip>

If you read what I had written previously it would be obvious to nearly anyone. Hint: closed circulatory system, blood, pumping heart with valves and cardiac conduction for the CV system alone are required.

Christine Janis wrote:And humans at one stage in development, before the formation of the intratrial and intraventricular septa, also have this impossible "partially developed" system --- how on earth do they survive in the womb?

Because the uterus is a protected environment for the development of a human. This is why the baby will die if born too prematurely. The statement of yours above is the kind of nonsense expected of someone who believes that heart valves supposedly evolved before cardiac conduction.
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Re: Evolution of the cardiovascular system is impossible

Postby a_haworthroberts » Sun Mar 01, 2015 11:44 pm

Frank has awaken out of his extended hibernation. Can Spring be far away?
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Re: Evolution of the cardiovascular system is impossible

Postby Christine Janis » Mon Mar 02, 2015 9:45 am

Frank has awaken out of his extended hibernation. Can Spring be far away?


Ah, the longer days bring out the creationist Gish Gambol.

Will consider replying to this new barrage of argumentation from incredulity at some later point. However, I will take the time now to point out the basic structure of Frank's argument, which has changed not one whit.

Frank: The human heart has all these incredibly intricate features, without which it would be unable to function. Thus it must have been designed by God.

Me: Here is an example of a vertebrate heart that lacks feature X (e.g., coronary vessels, not present in most reptiles, any amphibian, many fish). Thus your assertion is invalidated.

Frank: That's just a story!

Me: No, it's an example of vertebrate anatomy which negates your original argument.

Frank: But you can't explain how the incredibly detailed nature of structure X came to exist, you're just waving a magic wand and calling it "evolution".

Me (straining to hear against the sound of shifting goal posts): No more than you can explain how it came to exist except by claiming that your god waved a magic wand.

I will also note that Frank's detailed knowledge of the anatomy of the human cardiovascular system stands in stark contrast to his shocking ignorance of the CV system of any other animal. Will point out some fun howlers later.
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Re: Evolution of the cardiovascular system is impossible

Postby Christine Janis » Mon Mar 02, 2015 9:29 pm

OK, will start in on Frank's first petit galop

Also, the dual CV system consists of a systemic circulation pumping blood to the body and a pulmonary circulation providing oxygen and carbon dioxide exchange with the respiratory system.


Hmm. I see that because I mentioned "gills" in the fish systemic system Frank blanked on the fact that the systemic circulation in fish is virtually identical to that in humans --- a system that pumps blood to the body (and the head), but which in fish is first routed via the gills because that's the source of oxygen pickup (in those fish without lungs). All vertebrates have a systemic system of circulation. But tetrapods and many bony fish have added the pulmonary circuit as well (indeed, this appears to be a primitive bony fish feature, lost in teleosts that turn the lung into a swim bladder).

Of course, this fishy form of the systemic circulation is true in humans too ---- the systemic circulation sends blood via a series of six aortic arches to the pharyngeal pouches, the gaps between which turn into the gill slits in fish. Strange that, while fish retain at least 5 of these arches, humans always lose 3 of them. Why would we have this fish-like setup as embryos if not reflecting shared developmental history? I note that he completely punted on answering this question before, but instead went back to the argument from incredulity about the complexity of the human system. He might claim that I"m "telling stories", but I'm proposing an explanation that fits the observable facts, while he is conveniently ignoring them. I wonder if Frank can come up with a design plan that includes these apparently surplus embryological blood vessels in humans going to the area that form the gills in fish.

"So how did the coronary arteries and veins, which form a closed system for the heart, supposedly evolve?! Each coronary artery and vein in humans has three layers – tunica adventitia, tunica media and tunica intima, so remember to explain how these layers supposedly evolved. Neural innervation of the coronary vessels provides vasodialation, which needs to be explained as well. Of course the consequence of having limited blood flow to the coronary vessels (myocardial infarction) cannot be ignored."


Of course we don't know exactly how things evolved --- all we can do is look at the evidence that is here today. Many vertebrates have hearts that function quite well without coronary vessels, and indeed coronaries appear to have evolved at least 4 times (in sharks, teleosts, in mammals, and in archosaurs). So the notion that coronary vessels are essential for vertebrate heart anatomy is clearly falsified.

I don't know enough about the details of coronary vessel anatomy in all vertebrates, but I'd be willing to bet that the system of layers of the vessels in humans can be found in a less complicated fashion in other extant vertebrates (extant mammals, in this case). Neural innervation is no problem, as all tissues during development attract circulation and innervation, they're not a separate add on. One might as well ask how could it be that humans could be born with a 6th finger, as not only would there have to be a gene for the sixth finger, but also a gene for the finger nail, the skin, the blood vessels, the bones, the nerves, etc. Clearly absurd as organismal parts develop as an integrated system, not a bunch of independent units that need to get cobbled together.

Does Frank perhaps imagine that God sits in on every human development, making sure that the coronaries get their nervous supply like he originally ordained?
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Re: Evolution of the cardiovascular system is impossible

Postby Christine Janis » Sat Mar 07, 2015 10:20 pm

Same old nonsense from Janis. Once again, this is known as the logical fallacy of circular reasoning. By saying “the six original aortic arches” you are assuming evolution to start with, which means your argument is circular. Understand?! Here is what you should have responded to


There is nothing wrong with my saying "the six original aortic arches" as they are the ones that form in the embryos of all vertebrates. Thus they were the original ones in you and me, as well as every other vertebrate. Whether or not one chooses to make the strong inference from this that the common ancestor had six arches (as can perhaps also be inferred from the Early Cambrian vertebrates), the word "original" here is pertinent.

I note that you made no attempt to correct your misinterpretation of what I meant by six "aortic arches". Those are the embryonic arches, retained in you and me as the carotid (the 3rd arch), the systemic = aorta (the 4th arch) and the pulmonary (the sixth arch). Instead you name six branches of the aorta in adult humans. Could it be that you failed to understand the issue? Or were you just punting because you couldn't answer the question? As a medical specialist you should surely know the difference between "aortic arch" and "branch of the aorta".

There really is no "design" explanation for the embryonic existence of arches 1, 4 and 5 in humans (indeed in all tetrapods, although 5 is present in salamanders), or aortic arch 1 in all extant vertebrates. But common ancestry and evolution provide an excellent explanation.

Here is what you should have responded to:


Why? Why should I respond to issues of your choosing when you punt on the ones that I choose? But I will now.

The sinoatrial node in the human heart is a group of autorhythmic cells that acts as the pacemaker of the heart. It is only a very small part of the human heart. The amphioxus “heart” has no valves, no separate chambers, no endocardium and no epicardium. Fluid is pumped by the pulsing of arteries. So much for the amphioxus “heart” being homologous with the human heart."


I never said that the entire heart of amphioxus is homologous to the human heart. I said that, even in this primitive chordate, there is an element of the pumping heart (the sinus venosus = sinoatrial node) that is indeed homologous (and I'd wager that the genetic evidence shows that too). Your original argument was that hearts could not exist without all of the components. Here is an extant animal with just one component of the human heart that is doing very well. And, in the heart of amphioxus, fluid is most certainly not "pumped by the pulsing of arteries". It's pumped by the the sinus venosus and the various accessory hearts (some of which can be seen in hagfish, but not in other vertebrates).

Typical of evolutionists, you have failed completely to specify what is required for sympathetic innervation of the heart.


Irrelevant, as fishes have many homologous elements of the human heart yet lack sympathetic innervation of this organ. To remind you --- your original point was that hearts cannot function without all of the components seen in humans. Yet over half of the species on the planet today lack this sympathetic innervation that you hold so important. Sure the system in humans is complex, but declaring "intelligent agency" without looking at the comparative information on related species is simple assertion without application of the scientific method.

"The fallacy of your argument is assuming that similarities show evolutionary relationships. Dolphins have a similar body structure to sharks, however dolphins are mammals and sharks are fish, which are not related according to evolutionary theory.


My argument, or rather the argument of legitimate science, is not that "similarities" show evidence of relationship, but that *homologies* do. The similarity of dolphins and sharks is a superficial one, related to the demands of the laws of physics (i.e., Reynolds numbers) on general body form of large, fast swimming aquatic organisms. Also, you need to take into account that the molecular data (of varied sources, including the independent data of nuclear DNA, mitochondrial DNA, and microRNA, plus the insertion of viral elements [ERVs] all support the phylogenies originally derived from morphological data.) The detailed differences between sharks and dolphins are immense, and would take pages to list. But I like this bit:

which are not related according to evolutionary theory


I guess that you follow the bible, then, in thinking that Jonah was swallowed by a really big fish. Cute, but not scientific.

Also, if similarities supposedly show evolutionary relationships, then conversely non-similarities must show that animals are not related, such the large difference between the single circulation CV system of fish and the dual circulation CV system of mammals, birds, amphibians and reptiles."


The non-similarities between dolphins and fish, which include the circulatory system amongst other items, do indeed show that dolphins are not fish. However, there are many other similarities that show that dolphins and fish belong in the same subphyum, Vertebrata. So, at a deep level they are related, but within the vertebrates they are not closely related. Also, you seem to have forgotten that lungfish, and a number of primitive bony fishes (Polypterus [reed fish], Amia [bowfin] and Leipsosteus [garpike] do indeed have this dual circulatory system that you think is unique to tetrapods. But that's typical of trying to explain anything to creationists: they simply ignore the facts that you present, pretend that they don't exist, and then go on to making up their own set of "facts" in a vain attempt to win the argument.
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Re: Evolution of the cardiovascular system is impossible

Postby Christine Janis » Sat Mar 07, 2015 11:01 pm

In your own words: “Hagfish don’t have a vertebral column, so are not vertebrates such as fish, amphibians, reptiles, birds and mammals.” This was your comment, not mine.


That was, I admit, poorly worded. What I should have said is that hagfish (and lamprey) do not have a full vertebrate column with a centrum (as seen in jawed vertebrates). However, many other anatomical (and molecular) pieces of evidence show that the cyclostomes (i.e., hagfish and lamprey) are the sister taxon of gnathostomes (jawed vertebrates), and they have always been placed together within the subphylum Vertebrata. Not sure what type of point you think you've scored here --- except to brag about the fact that something you learned in school in the 1950s seems to contradict my testament of the position of today's science.

"Also, you have provided absolutely no evolutionary explanation for the origin of red blood cells in lamphreys or hagfish. So in effect you have made the situation twice as impossible to answer as I described with the origin of the erythrocytes in the skeletal system."


Well, now the goal posts have shifted from the heart to the red blood cells. Obviously this is not a question that is easy to address, but you're invoking the God of the Gaps argument in that, "if science can't produce the answer within 5 seconds of my snapping my fingers, that means that God did it and I win." However, a simple google search on the issue turned up this:

http://bloodcenter.stanford.edu/blog/ar ... cs-ev.html

Here's what the U.S. National Library of Medicine, National Institute of Health has to say: "The most primitive blood cell may have been a protohemocyte which was first involved in phagocytosis and nutrition. When metazoans (sponges) appeared [hundreds of millions of years ago], their "blood" cells, the archeocytes, were phagocytic. [Later] a progressive differentiation of several leukocytic types occurred. Differentiated cells appeared that distributed food and oxygen, thus erythrocytes evolved in certain marine or polychaete annelids [worms]."

In other words, the earliest ancestor of blood cells may have been one type of cell that provided both immunity and energy to the organism. Later, in what may have been sponges or marine worms, this “proto” blood cell evolved into several types of cells involved with immunity (WBCs) and other blood cells that distributed nutrients (plasma) and oxygen (RBCs).


So I guess that scientists have been thinking about this, and proposing hypotheses. I was interested enough to google it. You were not.

To continue

"This must be the ultimate hand-waving argument. To state the obvious, you have failed to even mention the respiratory system that is found in vertebrates that is used for the ventilation and perfusion of oxygen and carbon dioxide.


You mean gills? That's what over half of the species alive today use. Oh, I guess not, because, like all creationists, all you care about is humans.

You have failed to explain (or even mention) how the respiratory system of mammals supposedly evolved. No mention of lungs, the bronchial tree, alveoli or breathing.


Mammals again. Does nobody else have lungs? Ah yes, many fish have lungs, as a simple outpocketing of the pharynx. All fish that have lungs "breathe" in the sense that you mean --- but again all fish pump water over the gills to obtain oxygen, which you don't care about because God supposedly created Man in his own image, which was not that of a fish. (Or *was* it?? Why is Jesus so often depicted by a fish symbol?)

Simply wave the magic evolutionary ward and these structures appear. But the magic evolutionary wand must be waved again to produce a diaphragm, because this is needed for breathing.


Like I said, primitive types of lungs (and a dual circulation system) are seen in some fish today. Lungfish go a step further that the rayfinned fishes, and route the pulmonary vein directly into the heart rather than into the common cardinal vein (plus they have a divided atrium).

Here's a nice little sequence of animation I designed that shows the differences in extant vertebrates (plus a little speculation on some common ancestral conditions), including the lungs and dual circulation a basic system in bony fishes.

http://creaturecast.org/archives/2634-t ... lar-system

Also, if the diaphragm is necessary for breathing, how come fishes with lungs, amphibians, reptiles and birds manage to ventilate their lungs without it? The diaphram is merely a muscularized version of the septum that divides the peritoneal cavity in all vertebrates with lungs. No great mystery there.

Neural innervation of the diaphragm is required for the diaphragm to function, so the magic evolutionary wand must be waved again.


As a medical specialist you should know that any structure that grows during development will attract the accompanyment of nervous tissue. Muscle tissue growing into the peritoneal septum carries with it its own nerve supply.

"What completely ridiculous nonsense! For starters, you have started off with a lancelet which has a closed circulatory system with pulsing arteries. You have failed to provide an evolutionary explanation for this animal. So the magic evolutionary ward is waved and an atriam and ventricle and two heart valves supposedly evolved?! Heart valves work in conjunction to provide a one-way flow of blood through the circulatory system. So you are claiming that cardiac conduction evolved after heart valves supposedly evolved?! Without cardiac conduction, there will be no pumping of blood (even with valves) and death will occur; this is stating the obvious."


Er, no. I'm proposing, as you seem to have forgotten, that the cardiac conduction system (the sinoatrial node) actually precedes the vertebrate heart, as this structure is seen in amphioxus, and is the major pacemaker of blood pumping in all chordates. Interesting that, if you are indeed a medical specialist, that you misspell "atrium". Makes me wonder if you're not just copying out big words from a medical textbook.

This is a nice article that shows that the pacemaker cells in the hearts of tunicates (which molecular data now show to be more closely related to vertebrates than is amphioxus) are homologous with the ones in humans.

http://eu.wiley.com/WileyCDA/PressRelea ... 00481.html

An international team of molecular scientists have discovered that star ascidians, also known as sea squirts, have pacemaker cells similar to that of the human heart. The research, published in the JEZ A: Ecological Genetics and Physiology, may offer a new insight into the early evolution of the heart as star ascidians are one of the closest related invertebrates to mammals.

The research team, led by Annette Hellbach from the Max Planck Institute of Biochemistry in Germany, expected to find clusters of HCN cells, the markers for pacemakers, at either end of the Botryllus schlosseri ascidian heart.

“The Botryllus schlosseri heart beats from one end to the other, stops for a short while and then starts to beat in the other direction,” said Hellbach. “It would make sense to have two pacemakers on both ends from which the heartbeat is initiated, however, we found several HCN positive cells spread along the cardiac tube.”

The team interpreted this finding as an evolutionary precursor to the elaborate cardiac conduction system found in mammals which are made up of clusters of pacemaker cells located in defined spots.

The team found that in comparison the cells in the B. schlosseri heart appeared to be randomly distributed along the heart; however, as with mammals the HCN cells played a vital role in generating the heartbeat.

The team also found that the cells responded to the blocking chemicals Cilobradine and Zatebradine by decreasing the heartbeat as is found to be the case for mice. This increases the likelihood that the cells operate through a similar molecular function.

“Our study reveals that the presence of HCN channels and their role in generating the heartbeat is shared between B. schlosseri and mammals,” said Hellbach. “This makes colonial ascidians such as B. schlosseri insightful models for studies on the origins and evolution of vertebrate innovations, such as the pacemaker.”
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Re: Evolution of the cardiovascular system is impossible

Postby Christine Janis » Sat Mar 07, 2015 11:09 pm

Christine Janis wrote:

Frank wrote:It is rather amusing that you need to resort to the discredited pseudoscience of Ernst Haeckel (“ontogeny recapitulates phylogeny”). You are totally confused between origins science and operations science in claiming that embryological development has anything to do with supposed evolutionary development. How an animal supposedly survived in its environment with a partially developed CV system is not addressed.


And I wonder what Frank means by a "partially developed CV system".<snip>


If you read what I had written previously it would be obvious to nearly anyone. Hint: closed circulatory system, blood, pumping heart with valves and cardiac conduction for the CV system alone are required.


As i noted, hagfishes lack a completely closed circulatory system and also lack any autonomic innervation of the heart (although they do have a cardiac conduction system). Amphioxus (and tunicates) have an open circulatory system and, of course, blood, and also a cardiac conduction system (see above about the tunicate pacemaker cells). But they don't have a valved heart. So, we have extant animals, which molecular data shows to be related to vertebrates, that lack some of the components that you deem to be essential for a cardiovascular system to function. And they survive quite well in their environment. So I guess that I don't need to explain anything here.

The statement of yours above is the kind of nonsense expected of someone who believes that heart valves supposedly evolved before cardiac conduction.


If you read my posts, I clearly don't "believe" this, seeing as a cardiac conduction system is seen in all chordates, but heart valves are only seen in vertebrates. Ergo, a cardiac conduction system is the more generalized condition, and the possession of heart valves the more specialized one, within our own phylum.

I wonder how many months it will take Frank to figure out a new form of rebuttal.
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Re: Evolution of the cardiovascular system is impossible

Postby Frank » Fri May 20, 2016 2:57 am

Christine Janis wrote:
Ah, the longer days bring out the creationist Gish Gambol.

Will consider replying to this new barrage of argumentation from incredulity at some later point. However, I will take the time now to point out the basic structure of Frank's argument, which has changed not one whit.

Frank: The human heart has all these incredibly intricate features, without which it would be unable to function. Thus it must have been designed by God.

Me: Here is an example of a vertebrate heart that lacks feature X (e.g., coronary vessels, not present in most reptiles, any amphibian, many fish). Thus your assertion is invalidated. <snip>

What a complete load of drivel. Of course, it is a lot more difficult refuting what I actually wrote, rather than your fictitious nonsense. Firstly, your claim that that I am using “argumentation from incredulity” is the logical fallacy known as circular reasoning because it assumes that evolution is true to start with. My argument is that intelligent design is the inference to the best explanation for life because we know for a fact that intelligent agents (humans) are capable of building systems that have similar functionality to those found in life. For example the engine management system in cars functions similarly to the autonomic nervous system in humans.

However even with your fictitious dialog you have failed to refute what I supposedly wrote, because the human heart will not function without coronary blood vessels and a blood supply. People die from myocardial infarction. Also, you have absolutely no explanation as to how the coronary blood vessels supposedly evolved. What preposterous nonsense it is to claim that the metabolic requirements of the myocardium just happened to be met by the chance development of a closed system of coronary arteries and veins. Such nonsense only occurs in the minds of evolutionists, not in the real world.
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Re: Evolution of the cardiovascular system is impossible

Postby Frank » Fri May 20, 2016 3:15 am

Christine Janis wrote:
Frank wrote: Also, the dual CV system consists of a systemic circulation pumping blood to the body and a pulmonary circulation providing oxygen and carbon dioxide exchange with the respiratory system.

Of course, this fishy form of the systemic circulation is true in humans too ---- the systemic circulation sends blood via a series of six aortic arches to the pharyngeal pouches, the gaps between which turn into the gill slits in fish. Strange that, while fish retain at least 5 of these arches, humans always lose 3 of them. Why would we have this fish-like setup as embryos if not reflecting shared developmental history?

Once again, your argument is a complete fallacy. Evolutionists believe that fish transformed into humans over millions of years, and these vertebrates have vastly different body systems. Yet you claim that similarities in embryonic aortic arches in fish and humans indicate common ancestry. You also claim that fish end up with a different number of aortic arches than humans. So you claim that structural differences are evidence for evolution, and structural similarities are also evidence for evolution. Evolutionary theory is so plastic that anyone can invent any story to explain the data. No doubt if humans had five, seven, or any other number of aortic arches then you would also fabricate another story about how this number of aortic arches changed over millions of years. Your interpretation of the data is not science, it is meaningless story telling.

Christine Janis wrote:He might claim that I"m "telling stories", but I'm proposing an explanation that fits the observable facts, while he is conveniently ignoring them.

Complete nonsense. As described above, my interpretation of the data takes into account the complete body structure of fish and humans, whilst yours selectively looks at similarities of aortic arches only, and completely ignores the massive differences of other body structures. Your selective use of data is not science. The mammalian heart develops before the circulatory system, which contradicts the evolutionary sequence. Also, the human embryo has a post anal gut, so does this mean that humans are related to animals with the same?

Christine Janis wrote:I wonder if Frank can come up with a design plan that includes these apparently surplus embryological blood vessels in humans going to the area that form the gills in fish.

Pharyngeal arches in humans are neither gills nor slits. The blood vessels you mention are formed because the head region of the embryo from a very early stage of development requires an abundant blood supply. Your argument is based on ignorance and special pleading, it is not science.

Christine Janis wrote:
Frank wrote:"So how did the coronary arteries and veins, which form a closed system for the heart, supposedly evolve?! Each coronary artery and vein in humans has three layers – tunica adventitia, tunica media and tunica intima, so remember to explain how these layers supposedly evolved. Neural innervation of the coronary vessels provides vasodialation, which needs to be explained as well. Of course the consequence of having limited blood flow to the coronary vessels (myocardial infarction) cannot be ignored."

Of course we don't know exactly how things evolved --- all we can do is look at the evidence that is here today. Many vertebrates have hearts that function quite well without coronary vessels, and indeed coronaries appear to have evolved at least 4 times (in sharks, teleosts, in mammals, and in archosaurs). So the notion that coronary vessels are essential for vertebrate heart anatomy is clearly falsified.

This is a strawman logical fallacy argument, as I never said that coronary vessels are essential for all vertebrates. To believe that coronary blood vessels evolved once is totally absurd, but to believe that they evolved four separate times is orders of magnitude even more absurd. Your evolutionary explanation for the coronary blood vessels is not science.

Christine Janis wrote:I don't know enough about the details of coronary vessel anatomy in all vertebrates, but I'd be willing to bet that the system of layers of the vessels in humans can be found in a less complicated fashion in other extant vertebrates (extant mammals, in this case). Neural innervation is no problem, as all tissues during development attract circulation and innervation, they're not a separate add on.

But you have failed to explain how this hypothetical, less complicated coronary circulatory system supposedly evolved. Also, what you mention here about neural innervation has absolutely nothing to do with evolution, instead you are talking about repeatable embryological development which is driven by pre-programmed genetic and epigenetic information. You are totally confused between origins science and operations science. Your attempt to explain the supposed evolutionary origin of coronary vessels has failed totally. What total nonsense.

Christine Janis wrote:One might as well ask how could it be that humans could be born with a 6th finger, as not only would there have to be a gene for the sixth finger, but also a gene for the finger nail, the skin, the blood vessels, the bones, the nerves, etc. Clearly absurd as organismal parts develop as an integrated system, not a bunch of independent units that need to get cobbled together.

To state the obvious, the genetic information for fingers already exists so there is nothing remarkable about the development of a sixth finger. You have failed to even attempt to explain how a closed system of blood vessels pumping blood to meet the metabolic needs of the body supposedly evolved, and this is my main argument. Of course the real reason you cannot provide an explanation is because all of reality denies such an event occurring, ever.
Frank
 
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