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Still_human

Hey everyone, this is for anything Sphenacodont--dimetrodon, or otherwise. Collections/pictures/discussions/whatever. This is the splinter thread off of the sphenacodont collections thread, so if anyone would like to bring over anything from the other thread, please feel free. I'm going to bring over some interesting posted info that covered different topics, and with links to interesting and useful info.

 

*some discussions covering other things and animals in relation to sphenacodonts is perfectly fine. For instance, spinosaurus, Permian topics, apex predators, or whatever. As long as it has some relation. Side-tracking is fine, just bring it back home before too long, please.

 

Here's a link to the previous thread. It would be greatly appreciated if you post pictures of any dimetrodon/sphenacodont fossil material you have:)

 

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Still_human

One of the more interested topics discussed was the buffalo-back theory of sailed animals-dimetrodons and spinosaurs. Heres some links and cited info that were posted...

 

 

*(Information provided by Kane)

"buffalo back" hypothesis:

 

Bailey, J.B. (1997). "Neural spine elongation in dinosaurs: sailbacks or buffalo-backs?". Journal of Paleontology 71 (6): 1124–1146.

 

This was initially proposed by Ernst Stromer in 1915 for Spinosaurus. He called the hump Fettbuckel.

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Still_human

*(link from Walt)

 

I thought science always looked for modern day examples to explain that which we cannot see.  Why would there be that big a difference in such a feature as a sail fin?

Photo from https://reptilis.net/2014/06/21/tall-spines-and-sailed-backs-a-survey-of-sailbacks-across-time/

 Trioceros cristatus in life and under X-Ray. Note the prominent sail with visible outlines of the spinous processes. Images by: Benjamin Klingebiel (living), and J.M. Eder and E. Valenta (X-Ray)

 

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Kane

Inferring from existing species to determine the composition, morphological characteristics, habits, etc., of extinct species is conjectural at best. It can create some possibly plausible theories, but they cannot be tested or confirmed. I could not, for example, infer too much about the life of trilobites by observing modern day crabs.

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Jaimin013

Awesome Dimetrodon replica skull

 

Dimetrodon side label-1.jpg

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Walt
2 hours ago, Kane said:

Inferring from existing species to determine the composition, morphological characteristics, habits, etc., of extinct species is conjectural at best. It can create some possibly plausible theories, but they cannot be tested or confirmed. I could not, for example, infer too much about the life of trilobites by observing modern day crabs.

Not sure I agree with all of that....we can only hypothesize on how these creatures lived based on what we see around us.  Then we prove or disprove the hypothesis from information we glean in the rock record.  For instance, we know that trilobites occupied all levels of the water column based on the types of eyes they evolved.  We would not make that connection if we had not already observed how present day animals function at different levels of the ocean.  There is even a good chance that blind trilos lived at depth based on the fact that many modern animals who live at depth are blind.  Conversely, I'm sure the first scientists to study trilobites hypothesized that the eyes were nothing more than what you find on a dragon fly.  Done deal.  Move on, they may have said.  We now know this is not true. Once we decoupled our assumptions between modern day animals and trilos, we discovered a vision system which is amazing and which continues to amaze.

As to other instances, we look to modern animals in order to animate dino representations in movies and documentaries.  Look at how we had them animated in the 50's before we began to understand the connection to birds.  Now many of the dinosaurs are animated to act "birdlike".  We tested this theory as soon as computer animation allowed us to virtually move them.  However, even that is constantly being evaluated as we find new bones and realize this action or that was not possible.  But our modern animals were the starting point.  I'm Just saying that I do not believe nature necessarily throws out a design that works, as in the case of "sailed" animals. 

Anyway, just my uninformed, unsupported, opinion :D  I would love to research and see if it could be supported, but for now it will have to stay one man's opinion.

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Kane
7 minutes ago, Walt said:

Not sure I agree with all of that....we can only hypothesize on how these creatures lived based on what we see around us.  Then we prove or disprove the hypothesis from information we glean in the rock record.  For instance, we know that trilobites occupied all levels of the water column based on the types of eyes they evolved.  We would not make that connection if we had not already observed how present day animals function at different levels of the ocean.  There is even a good chance that blind trilos lived at depth based on the fact that many modern animals who live at depth are blind.  Conversely, I'm sure the first scientists to study trilobites hypothesized that the eyes were nothing more than what you find on a dragon fly.  Done deal.  Move on, they may have said.  We now know this is not true. Once we decoupled our assumptions between modern day animals and trilos, we discovered a vision system which is amazing and which continues to amaze.

As to other instances, we look to modern animals in order to animate dino representations in movies and documentaries.  Look at how we had them animated in the 50's before we began to understand the connection to birds.  Now many of the dinosaurs are animated to act "birdlike".  We tested this theory as soon as computer animation allowed us to virtually move them.  However, even that is constantly being evaluated as we find new bones and realize this action or that was not possible.  But our modern animals were the starting point.  I'm Just saying that I do not believe nature necessarily throws out a design that works, as in the case of "sailed" animals. 

Anyway, just my uninformed, unsupported, opinion :D  I would love to research and see if it could be supported, but for now it will have to stay one man's opinion.

Actually, science cannot prove or disprove anything. Proof only works in mathematics and logic, not science. What science can do is falsify and create useful predictions that can further be falsified, as per the empirical method. What you are describing is a species of forensics. 

 

A classic example would be how Einsteinian relativity falsifies Newtonian mechanics with respect to the orbit of Mercury.

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Walt

"In the empirical sciences, which alone can furnish us with information about the world we live in, proofs do not occur, if we mean by 'proof' an argument which establishes once and for ever the truth of a theory" - Karl Popper

 

How can I argue with something so eloquently put :)

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Still_human
7 hours ago, Kane said:

Actually, science cannot prove or disprove anything. Proof only works in mathematics and logic, not science. What science can do is falsify and create useful predictions that can further be falsified, as per the empirical method. What you are describing is a species of forensics.

I'm not sure I follow. Im guessing you're referring to a specific aspect of science, like as far as extinct animals, and such? Cause science as a general idea has lots of proof. It's proven that we need oxygen and food to survive. Even scientific "theories" are proven--the theory of evolution is proven(well, depending on the state your in, anyway). We see it happen, and even make it happen. You're referring to things that we can't directly observe, right? I have a feeling I may just be misinterpreting what you mean.

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Still_human
7 hours ago, Kane said:

Proof only works in mathematics and logic

How so with logic? Isn't the entire idea of logic trying to understand something without help/proof? Coming up with a conclusion simply because it's the logical answer? Which wouldn't actually mean it's even the truth, because plenty of things appear to contradict what would be considered logical. I'm assuming again though, that I'm probably completely misinterpreting what you're saying.

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Still_human
On 8/22/2018 at 3:37 PM, Jaimin013 said:

Awesome Dimetrodon replica skull

 

Dimetrodon side label-1.jpg

It sure is beautiful! I actually see a lot of dimetrodon skull replicas(actually, multiple full body reps, too!), and most of them really are works of art! I don't like reproductions in general, but I wouldn't mind most of the metro skulls I see(or full bodies!). At least full size ones. I don't like non-scale reproductions. At least not enough for me to want one.

 

its actually kind of strange. As was brought up on the other thread, dimetrodon fossils seem to be significantly fewer than dinos, possibly due to the interest level, yet I come across more dimetrodon reproductions than anything else by FAR, except ichthyosaur fossil slabs(partial and full body).

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Kane
8 hours ago, Still_human said:

I'm not sure I follow. Im guessing you're referring to a specific aspect of science, like as far as extinct animals, and such? Cause science as a general idea has lots of proof. It's proven that we need oxygen and food to survive. Even scientific "theories" are proven--the theory of evolution is proven(well, depending on the state your in, anyway). We see it happen, and even make it happen. You're referring to things that we can't directly observe, right? I have a feeling I may just be misinterpreting what you mean.

Walt gives a strong clue in quoting Karl Popper - take that as a great recommendation to understand the fundamentals of science.

 

There is no proof in science. A proof (particularly in mathematics) is self-evident and can be traced to an axiom. For example, there is no need for testing or observation to know that the square root of 2 is an irrational number. In terms of logic, it depends on what kind of logic. Informal reasoning aside, if we take symbolic or propositional/binary logic, there are clear rules to the procedures to determine the conclusion without appeal to evidence or observation. Operators include and (conjunction) or (disjunction) if/then (conditional) if-and-only-if (biconditional) and not (negation). Logic is less about truth (in reality) and more about validity according to its rules. For example, I cannot say if P then Q, Q, therefore P as that affirms the consequent and is thus invalid. Or, if presented with another variable that sets up a counterexample, this invalidates and absolute statement. To make that simpler, if I write "all swans are white" (for each swan S, S has property W), and we add a black swan, then the quantifier is invalid, and we'd have to change it from (XS) S > w to (Ex) S > (w V b). That is, if there exist some swan then it will either be white or black. Anyway, this is just basic logic, and the more complex forms have an even more visible connection to theorems and proofs. Math and logic are a form of art in many respects. In math, one can construct viable proofs for structures that cannot be created in three-dimensional space.

 

The theory of evolution is not proven. It is highly probable to near probability-1, but has it always been true? Will it be true for all time? For all organisms? That we cannot know as we have not encountered all organisms in the universe. That the earth will rotate on its axis so that you see the sun rise tomorrow is also not a proof, or something that can be proven, as there may be a day it does not (not likely), but at some point in the future this event may not occur. Consider that if science proves anything, then it no longer can be tested because it is established as being true for all time. Theory tells us HOW something happens (like evolution), not WHY, and is useful for prediction. Still, science is in the service of falsification, and that process is never settled. 

 

Your use of proof is more in the common vernacular than its actual technical usage. Proof does not have to correspond at all with reality, any more than a chess game has to be real outside the bounds of its rules. 

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Still_human
5 hours ago, Kane said:

Walt gives a strong clue in quoting Karl Popper - take that as a great recommendation to understand the fundamentals of science.

 

There is no proof in science. A proof (particularly in mathematics) is self-evident and can be traced to an axiom. For example, there is no need for testing or observation to know that the square root of 2 is an irrational number. In terms of logic, it depends on what kind of logic. Informal reasoning aside, if we take symbolic or propositional/binary logic, there are clear rules to the procedures to determine the conclusion without appeal to evidence or observation. Operators include and (conjunction) or (disjunction) if/then (conditional) if-and-only-if (biconditional) and not (negation). Logic is less about truth (in reality) and more about validity according to its rules. For example, I cannot say if P then Q, Q, therefore P as that affirms the consequent and is thus invalid. Or, if presented with another variable that sets up a counterexample, this invalidates and absolute statement. To make that simpler, if I write "all swans are white" (for each swan S, S has property W), and we add a black swan, then the quantifier is invalid, and we'd have to change it from (XS) S > w to (Ex) S > (w V b). That is, if there exist some swan then it will either be white or black. Anyway, this is just basic logic, and the more complex forms have an even more visible connection to theorems and proofs. Math and logic are a form of art in many respects. In math, one can construct viable proofs for structures that cannot be created in three-dimensional space.

 

The theory of evolution is not proven. It is highly probable to near probability-1, but has it always been true? Will it be true for all time? For all organisms? That we cannot know as we have not encountered all organisms in the universe. That the earth will rotate on its axis so that you see the sun rise tomorrow is also not a proof, or something that can be proven, as there may be a day it does not (not likely), but at some point in the future this event may not occur. Consider that if science proves anything, then it no longer can be tested because it is established as being true for all time. Theory tells us HOW something happens (like evolution), not WHY, and is useful for prediction. Still, science is in the service of falsification, and that process is never settled. 

 

Your use of proof is more in the common vernacular than its actual technical usage. Proof does not have to correspond at all with reality, any more than a chess game has to be real outside the bounds of its rules. 

I would "find this informative" if I could understand it lol. I understand the last 2 sections, but not the first long one. But isn't all that proven for at least the time being? It may not be proven for all time, changing things over long periods of time, but can't we say it's a proven fact temporarily. Cause evolution is a proven fact for now, at least, even if we can't prove it for the past or future. And we wouldnt necessarily need to prove that the sun WILL rise tomorrow, because who knows what might happen before the, but we have proof that's how it works. Things interfering with the natural order doesn't change that things work a certain way, just that things are different, but not the proven idea of how something works. If the earth disappeared and no longer orbits the sun, isnt it still a 100% fact that something of the same size and mass distance from the sun, rotation of the earth, with an object the same size and mass as the moon orbiting it, and all the other exact  details of the earth that affect the orbit, will orbit the sun at the same speed that the earth did. Even if it doesn't anymore. Right?

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Kane

Proof is 100% certainty, but nothing in the physical universe is 100% proven. Instead, we speak of probability. If things were 100% proven, then the universe is entirely deterministic, which it is not according to science. 

 

Keep in mind that Newtonian mechanics in its entirety was accepted as "true" until parts of it were overturned by Einstein with relativity and adjustments to the third body problem. Something that is accepted as "true" at any given moment may be sufficient to base predictions, or even be applicable in engineering (Newtonian physics was sufficient to get humans to the moon, for example, but not for understanding the effect of the speed of light across larger distances for which one needs Einsteinian relativity). Again, what we accept as true in the moment is simply very high probability under given conditions, according to the evidence thus far gathered.

 

Your example of earth vanishing does not refute that we are still dealing with probabilities. To use another example, we cannot recreate at the atomic level certain phenomena such as smashing a plate with a hammer. We have no way of testing that as the conditions can never truly be replicated with 100% fidelity. We cannot rerun, say, the history of the earth except as simulations which still must traffic in probabilities, not proofs.

 

Once again, to get a deeper understanding, please read Karl Popper's The Logic of Scientific Discovery.

 

Also, this might be useful to ensuring semantic precision of key terms: https://oregonstate.edu/instruction/bb317/scientifictheories.html

 

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Still_human
20 hours ago, Kane said:

, Proof is 100% certainty, but nothing in the physical universe is 100% proven. Instead, we speak of probability. If things were 100% proven, then the universe is entirely determini stic, which it is not according to science. 

 

Keep in mind that Newtonian mechanics in its entirety was accepted as "true" until parts of it were overturned by Einstein with relativity and adjustments to the third body problem. Something that is accepted as "true" at any given moment may be sufficient to base predictions, or even be applicable in engineering (Newtonian physics was sufficient to get humans to the moon, for example, but not for understanding the effect of the speed of light across larger distances for which one needs Einsteinian relativity). Again, what we accept as true in the moment is simply very high probability under given conditions, according to the evidence thus far gathered.

 

Your example of earth vanishing does not refute that we are still dealing with probabilities. To use another example, we cannot recreate at the atomic level certain phenomena such as smashing a plate with a hammer. We have no way of testing that as the conditions can never truly be replicated with 100% fidelity. We cannot rerun, say, the history of the earth except as simulations which still must traffic in probabilities, not proofs.

 

Once again, to get a deeper understanding, please read Karl Popper's The Logic of Scientific Discovery.

 

Also, this might be useful to ensuring semantic precision of key terms: https://oregonstate.edu/instruction/bb317/scientifictheories.html

 

I get what your saying.....it's just find it too hard to just accept it all though. I understand and can accept the general idea, but it just seems too blindly all encompassing and unyielding. Like it's just another one of these unprovable "theories" that it's referring to. I feel silly saying I don't agree with part of a scientific theory, but I guess that's how science forwards itself...questioning things. Of course I'm definitely not the kind of person to be actually coming up with counter proposals and such lol

 

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Kane
43 minutes ago, Still_human said:

I get what your saying.....it's just find it too hard to just accept it all though. I understand and can accept the general idea, but it just seems too blindly all encompassing and unyielding. Like it's just another one of these unprovable "theories" that it's referring to. I feel silly saying I don't agree with part of a scientific theory, but I guess that's how science forwards itself...questioning things. Of course I'm definitely not the kind of person to be actually coming up with counter proposals and such lol

 

And don't get the idea that science is monolithic and stuffy, either! Many of the most amazing theories have their genesis in wildly imaginative thinking: gravity, entropy, atomic theory, DNA, relativity. What defines these from just crank theories or just metaphysics is rigorous testing. Some of Einstein's theories came to him, in nuce, through dreams. The trick was to test, falsify, repeat.

 

You might enjoy delving into the history of science, from the days of the Greek Atomists, to Aristotle's partial rejection of Platonism to incorporate more observation in the material world (though he did assume that there was no void, and that two objects of different masses fall at different speeds). And then with the printing press effectively de-monopolizing knowledge from the Church begat a whole new era of perspective in the Renaissance. Add in the invention of sense-extenders like the microscope and telescope whereby we could measure the world even better without relying simply on the limitation of our fleshy hardware. 

 

Skip the clock a bit forward, the Nova Organum by Francis Bacon in Elizabethan England, later on the theory of gravity and development of the calculus under Newton (although Leibniz claims he pioneered the latter :D ). Dalton, Boyle, Lamarck, Darwin, Maxwell... It's quite the mental trip if you choose to take it. :dinothumb:

 

Science is also very dependent upon its tools for measurement. We have been able to falsify various theories because of more refined tools. Mass spectrometers, faster computation power, chromatography, CT scanning, particle accelerators, satellite telescopes... And that process just gets more and more refined, extending our senses that much farther, that much deeper. :) 

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Still_human

Wow, that's quite a bit to take in lol! That last part is my kind of thing. I'm very into space sciences, quantum physics, most areas within physics. Quantum, particle, cosmo, astro. the natural sciences in general. Very much theoretical physics, too. I'll take a look into the things you mentioned. At the moment ive actually been looking into extinct spined biology!  

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Kane
2 hours ago, Still_human said:

Wow, that's quite a bit to take in lol! That last part is my kind of thing. I'm very into space sciences, quantum physics, most areas within physics. Quantum, particle, cosmo, astro. the natural sciences in general. Very much theoretical physics, too. I'll take a look into the things you mentioned. At the moment ive actually been looking into extinct spined biology!  

No harm in reading as much as you can! :) Sad thing is, life is just too short to absorb it all. 

 

I did forget to provide a good example with the earth orbit question you asked. The orbits of earth around the sun, and moon around the earth are observations - not theory, but it is an observation that Newton explains in his theory. We continue to use Newtonian theory to design earth-orbit satellites as the theory correctly predicts those orbits (it's how humans got to the moon!). However, his theory does not work when it comes to the orbit of Mercury, and is falsified. In order to explain that, you need General Relativity. So, simply put, Newtonian theory works locally, but not uniformly when we get away from two-body problems.

 

And the earth/moon, earth/sun orbits are just two-body problems. Consider the perturbations of other bodies outside those orbits. It is possible that a massive collision with earth could alter the orbit of the other planets, or a mass collision with the other planets might affect ours. Laplace asks if the universe is stable, and that remains an open question. We don't know. Add more bodies in the question, the predictions become less reliable without General Relativity. 

 

As a friend of mine puts it: "A scientific theory must make a prediction about something physical and the best that can be done is to either verify the prediction and then provisionally accept the theory or show it is a wrong prediction and then the theory is false." 

....

So, to bring this around to the Dimetrodon and Spinosaurus buffalo-back hypothesis, we might be able to come to some provisional acceptance of yea or nay on the basis of evidence. But this is trickier since unless we develop time travel or develop a means to measure the fossil remains in new and informative ways, we are not left with much to test and falsify. We are not yet at the stage to declare a theory, but a hypothesis. 

 

 

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siteseer

The thing I learned about Dimetrodon and other carnivorous sphenacodonts is that they represented the next level in the "arms race" between vertebrate predator and prey.  There were land predators in the Carboniferous Period but they had simple but sharp peg or cone-shaped teeth which were good for grasping and tearing to some extent.  Prey tended to be swallowed whole.  

 

In the late Carboniferous to Early Permian various synapsids evolved into the first herbivores on land like Edaphosaurus.  Among the carnivores like Dimetrodon there were at least two feeding innovations.  First, they had serrated teeth (something some sharks had already but not land animals).  Serrations along the tooth edges allowed flesh to be cut more efficiently.  A Dimetrodon could bit off a chunk of an animal larger than it could swallow, widening its range of prey than animals that lived before it.  It could also inflict more damage with less effort in a fight with another animal less well-equipped.

 

The other innovation was that Dimetrodon had teeth of different sizes in its jaws.  It was the beginning of what mammals have - different teeth having different functions.  It had small teeth at the front of the jaw for nipping/grabbing and larger teeth for stabbing (inflicting more injury) and then smaller teeth behind those for cutting.  The carnivorous therapsids of the mid-late Permian took these adaptations to an even greater level with other changes to the skeleton (faster running, stronger jaws, saberteeth, etc.).

 

 

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Bobby Rico
5 minutes ago, siteseer said:

The other innovation was that Dimetrodon had teeth of different sizes

Thank you that is a very interesting post. Also it is in it’s name Dimetrodon meaning "two measures of teeth” .:dinothumb:

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Still_human
21 hours ago, Kane said:

unless we develop time travel

IM ON IT!

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Still_human
21 hours ago, Kane said:

I did forget to provide a good example with the earth orbit question you asked. The orbits of earth around the sun, and moon around the earth are observations - not theory, but it is an observation that Newton explains in his theory. We continue to use Newtonian theory to design earth-orbit satellites as the theory correctly predicts those orbits (it's how humans got to the moon!). However, his theory does not work when it comes to the orbit of Mercury, and is falsified. In order to explain that, you need General Relativity. So, simply put, Newtonian theory works locally, but not uniformly when we get away from two-body problems

You've mentioned the Newtonian theory multiple times--I'll hafta check that out first. Seems very familiar, hopefully it's something I'll suddenly remember from before, when checking it out!

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Kane
3 minutes ago, Still_human said:

IM ON IT!

Lol! While you're there, pick me up some live trilobites. If you find yourself in 1998, invest in some Amazon and Apple stocks for me, will you? :D:P 

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