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The Undeniable Science of Biology
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avoiding the information from the video. |
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If the video you posted gives a definition of transitional fossil that you agree with, then I’d be happy to watch it. But I’d rather not invest 5 minutes of time in watching the video when I don’t know that’s the case. |
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Andrew I never have used the term. It seems redundant to me. Every species cand from another species. And given time and non-extinction, will evolve into something else. Absolutely. So… you get to define it and we’ll use YOUR definition. Fair? |
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@zorroloco “In my view, a transitional fossil is a fossil dug from the earth that has visible (not conjectured) features that demonstrate it is an intermediary between two established species. The features that cause it to be considered a transitional fossil have to be visible and not the result of extrapolation by imagination.” But I think we just view this too differently. If someone tells me the fossil record is evidence of the theory of evolution, the first questions that come to my mind are “How are you defining a transitional fossil?” and “How many are there?” I don’t assume all fossils (and all species) are transitional because I would then have the mindset that the theory of evolution is true and I’d be working backwards from that. I’m assuming it’s not true until I see enough evidence to believe it is. |
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08-Sep-22, 22:16 Transitional fossils <For example, there is quite good genetic data suggesting that the hippopotamus is closely related to the whales.> What does "closely related to" really mean? www.iatp.org www.sciencedaily.com |
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Andrew Parahoppis, who I’ve already mentioned, was a transitional eater. This is a horse that was transitioning away from eating trees leaves to eating grasses. www.floridamuseum.ufl.edu Or Archaeopteryx. Paleontologists view Archaeopteryx as a transitional fossil between dinosaurs and modern birds. With its blend of avian and reptilian features, it was long viewed as the earliest known bird. Discovered in 1860 in Germany, it's sometimes referred to as Urvogel, the German word for "original bird" or "first bird." Recent discoveries, however, have displaced Archaeopteryx from its lofty title. Archaeopteryx is a combination of two ancient Greek words: archaīos, meaning "ancient," and ptéryx, meaning "feather" or "wing." There are two species of Archaeopteryx: A. lithographica and A. siemensii. Archaeopteryx lived around 150 million years ago — during the early Tithonian stage in the late Jurassic Period — in what is now Bavaria, southern Germany. At the time, Europe was an archipelago and was much closer to the equator than it is today, with latitude similar to Florida, providing this basal bird, or "stem-bird," with a fairly warm — though likely dry — climate. Various specimens of Archaeopteryx showed that it had flight and tail feathers, and the well-preserved "Berlin Specimen" showed the animal also had body plumage that included well-developed "trouser" feathers on the legs. Its body plumage was down-like and fluffy like those of the feathered theropod Sinosauropteryx, and may have even been "hair-like proto-feathers" that resemble the fur on mammals, according to a 2004 article in the journal Comptes Rendus Palevol. Interestingly, the Archaeopteryx specimens found thus far lack any feathering on the upper neck and head, which may be a result of the preservation process. Based on its wings and feathers, scientists believe Archaeopteryx likely had some aerodynamic abilities. "The contour feathers in the wing and on the side of the tails of Archaeopteryx have an asymmetric shape, which is usually related to a higher aerodynamic performance," Christian Foth, a paleontologist at the University of Fribourg in Switzerland, told Live Science. "Thus, it is very likely that Archaeopteryx could fly, but it is hard to judge if it was a flapper or a glider." Archaeopteryx had a primitive shoulder girdle that likely limited its flapping abilities, but it also probably lived in areas without big trees for gliding, and its claw structure suggests it probably didn't climb often or perch on trees. "Therefore, we think that it could perform a simple flapping flight over a very short distance, maybe in relation to hunting or escape behavior," Foth said. A 2018 study published in the journal Nature Communications also found evidence that Archaeopteryx could fly, although not like any bird alive today does. The researchers used synchrotron microtomography — a tool that uses radiation to make magnified, 3D digital reconstructions of an object — to study the Jurassic creature's fossils. Even though Archaeopteryx didn't have the same features in its shoulders that help modern birds fly, its wings looked like those of modern birds that fly, they found. "Data analysis furthermore demonstrated that the bones of Archaeopteryx plot closest to those of birds like pheasants that occasionally use active flight to cross barriers or dodge predators, but not to those of gliding and soaring forms such as many birds of prey and some seabirds that are optimized for enduring flight," study co-researcher Emmanuel de Margerie, a researcher at The National Center for Scientific Research (CNRS) in Toulouse, France, said in a statement. Given that Archaeopteryx is the oldest flying member of the avialan lineage on record, it's likely that "active dinosaurian flight had evolved even earlier," study co-researcher Stanislav Bureš, a researcher at Palacký University in the Czech Republic. Other research, presented at the 2016 Society of Vertebrate Paleontology meeting in Salt Lake City, found that Archaeopteryx would have been able to fly without running first on the ground, Live Science reported. www.livescience.com |
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Whale evolution laid out The evolution of whales Lucas Lima and Earth Archives In Moby Dick, Herman Melville has his protagonist enumerate the reasons why scientists believe that whales are mammals, but then, with bold eloquence, he exclaims: “Be it known that, waving all argument, I take the good old fashioned ground that the whale is a fish, and call upon holy Jonah to back me.” That American classic was written in 1851, eight years before the publication of another classic that shook the intellectual world of its time: The Origin of Species. In it, Charles Darwin proposed that all species were descended from other species and eventually had one common ancestor. With whales being mammals, and mammalian ancestors being land animals, whale ancestors must have lived on land too. Even Darwin struggled with that concept, he proposed, in the first edition of his book, that whales might have evolved from ancestors that waded in rivers catching insects. This brought ridicule from his readers, and the statement was shortened in subsequent editions until whale origins was banished altogether in the last edition published during his life. Indeed, the land ancestry of whales remained a thorny issue for the scientists, as all fossil whales, throughout the 19th and much of the 20th century showed the fully aquatic features of animals that could not survive on land. Where were those land ancestors, or the intermediates to life in water, creationists demanded and they made fun of the idea that whales were somehow related to cows and their even-toed relatives, calling the idea an "udder" failure. That all changed in the 1990s and 2000s, when a remarkable series of fossils was discovered: intermediate animals showing a mix of land and water features water ancestral to all modern cetaceans (whales, dolphins, porpoises). The relevant fossil record went from non-existent to excellent, and confirmed the molecular biologists’ finding that the closest relatives of cetaceans were indeed the artiodactyls (even-toed ungulates including cattle, deer, pigs, hippos, camels, and giraffe). Now, so many fossils have been found that it became possible to study evolutionary changes in great detail, allowing an unprecedented understanding of land adaptations evolving into water adaptations. Such evolutionary changes occurred throughout the body. The limbs lost their function in body support, but now had to work as locomotor organs in the new, dense medium. The ears had to change, since sound in water is very different from sound in air. The nose shifted back onto the forehead, to make breathing while submerged easier. The kidneys also changed, since freshwater is not available to drink in ocean living mammals. And all of those changes, and many others, accumulated in short succession. In eight million years, cetacean ancestors went from land mammals to obligate marine swimmers. This early phase in cetacean evolution was characterized by great experimentation. There were crocodile-like whales, otter-like whales, and seal-like whales, and all these body plans were tested and then went extinct, until, in the end, only one body type was left. This is the same body type present in all roughly 90 modern species of cetaceans: a streamlined body with no neck, ending in a horizontally placed triangular fluke, lacking external hind limbs and with paddle shaped forelimbs, with a skin that is mostly devoid of hair, and a nose opening that forms the blowhole on the forehead. However, the traces of the ancestral land mammal ancestors are still retained in cetacean embryos, which have a distinct neck, with a long and narrow tail instead of a fluke, and with hind limbs that protrude from the body. Hairs are common on the faces of small fetuses, and the nasal opening is at the tip of the nose. With the new fossils and DNA data, molecular biologists were also able to solve Darwin’s vexing problem of what whales are related to. The DNA evidence points to one particular artiodactyl as the closest relative to whales: the hippopotamus. However, the last common ancestor of hippos and whales goes back some 50 million years, and it did not look at all like a hippo or a whale. Fossil evidence indicates that a nimble, deer-like mammal called Indohyus is even more closely related to whales. It is possible that both cetaceans and hippos are derived from Indohyus or a similar species. Indohyus lived near the northern edge of the Indian subcontinent at a time when the Himalayas were just forming, and the Tethys Sea separated the Indian and Asian land masses. It is here that cetaceans originated. Indoyus was the size of a cat, but proportionally more similar to a deer without antlers. In looks, Indohyus may have been similar to the modern mouse deer of Africa and Southeast Asia. Mouse deer eat fruits and leaves on the forest floor, and like to live near small streams. When they perceive danger, they jump into the water, hiding fully submerged. It is possible that Indohyus lived similarly, and that predator avoidance was the first aquatic behavior displayed by the ancestors of cetaceans. From the chemistry of the teeth, it is clear that Indohyus was a plant eater, and its dense bones suggest that they functioned as ballast, allowing the animal to stay submerged. Aged individuals have teeth that are worn down with use, and that tooth wear is different from that of related plant-eaters. In fact, the tooth wear looks more similar to that of the meat-eating early whales. This is a puzzle that is not solved and maybe Indohyus ate a kind of plant food that required processing by teeth similar to meat. That feature may have helped it as its descendants became meat-eating whales. The next step on the evolutionary ladder are the first cetaceans, pakicetids. Like Indohyus, pakicetids are only known from Pakistan and India. Even though they are the first whales, they looked nothing like modern whales. Instead, they were more similar to a large dog or wolf. Their fossils are only ever found in rocks that formed in shallow streams, never in the ocean, and it is likely that pakicetids were waders or bottom walkers in these streams. Their dentition indicates that they are meat eaters, and their eyes and ears are located high on the skull, a feature often associated with animals that have a submerged body, but are interested in things that happen out of the water, such as crocodiles spying for terrestrial prey. It is indeed thought that pakicetids were ambush predators, preying on land animals coming to the water to drink, or maybe catching fish trapped in shallow water. Around 48 million years ago, cetaceans moved toward the ocean. The first known species to do this is Ambulocetus natans. Ambulocetus is known from Pakistan, and only one complete skeleton has ever been discovered. It resembles crocodiles even more than pakicetids, while pakicetids had long limbs that could raise it up on land, Ambulocetus was more sprawling. Ambulocetus’ limbs are short, the tail powerful and the snout long. In spite of the short limbs, the feet are large, and they were probably the organ that these animals swam with. Even though there is an abundance of marine shells associated with the rocks that Ambulocetus is found in, it is also clear that there was freshwater nearby. Ambulocetus was possibly coastal, still taking advantage of thirsty prey coming to drink, but also venturing out in lagoons and the surf. Kutchicetus Following pakicetids and Ambulocetus in time as well as on the evolutionary branches leading to modern cetaceans are remingtonocetids, again a family known only from Pakistan and India. The trend toward more aquatic life continues, the limbs are shorter than in the earlier whales, and the tail is long and powerful. The shape of the vertebrae indicates that remingtonocetids do not have a fluke, but the tail vertebrae are somewhat flattened, suggesting that the tail was flat in the horizontal plane. It is likely that they swung this tail through the water in an up-down movement, which is of course the movement that the modern cetaceans make to propel themselves with their triangular fluke. Some other features are also indicative of more aquatic life. The eyes of remingtonocetids are small, suggesting that they were less important in catching prey, and indeed, the rocks that these fossils are found in indicate that many remingtonocetids lived in swamps with muddy water. The placement of the eyes is also unusual. Instead of being located on the top of the head, to see outside the water, remingtonocetid eyes are placed on the side of the head, consistent with hunting aquatic prey. The part of the skull that houses the remingtonocetid ear is large, suggesting that they had excellent hearing. It is likely that remingtonocetids used their ears in prey detection, a feature in common with modern toothed whales. Protocetid cetaceans lived at the same time as remingtonocetids, but in somewhat different habitats. In addition to South Asia, protocetids also conquered the oceans, and have been found in continents from Africa to South and North America. Unlike the earlier families, this implies that protocetids were able to cross large stretches of water and were thus good swimmers. They are a diverse group, with much morphological diversity. It is clear that some protocetids had a tail similar to that of ambulocetids and remingtonocetids, and it is also possible that some already had a fluke. Unlike remingtonocetids, protocetids are found in localities that indicate open, clear water, and they had big eyes. Protocetids are also the first whales in which the nasal opening is not near the tip of the snout, it has shifted higher up on the skull, although it is not a blowhole like it is in modern cetaceans. They still had powerful fore- and hind limbs allowing them to come ashore and get around on land, and possibly hauled out for functions related to reproduction, similar to modern sea lions. They may have been the first cetacean pursuit predators in open water. Basilosaurus The first fully aquatic cetaceans, and the group from which all modern cetaceans are derived, are the basilosaurids. Just like protocetids, basilosaurids are distributed widely across the world. Basilosaurids have the familiar attributes of modern cetaceans, they are streamlined, they have a fluke, and their forelimb is a paddle. Unlike modern whales, basilosaurids did have external hind limbs, but these were so small that they could not bear the animal’s weight, and their function, if any, is unclear. Some basilosaurids looked like a dolphin, and it is likely that their lifestyle resembled that of dolphins. The entire evolutionary sequence, from little Indohyus diving into streams, to modern cetacean-like basilosaurids took about 8 million years. Evolution designed new forms, tried them out, and discarded most of them, until at the end only the modern cetacean body plan remained. It is mind-boggling to think that all the different organs – limbs, ears, nose – had to change all at the same time, and one wonders how the genome changes needed to enable the morphological changes accumulated. With such a complete fossil record, a rich diversity of modern whales and their embryos, and the powerful new molecular techniques, it may be possible to approach that question. Could it be that some changes in the genome affected several disparate organ systems simultaneously, in fact creating an evolutionary shortcut that created novel morphologies at a high rate? This is an exciting concept. If we are able to identify some genes that are engaged in the development of multiple organ systems and that show consistent differences between cetaceans and other mammals, we may have identified the fingerprints of the process of cetacean origins. J. G. M. ‘Hans’ Thewissen is the Ingalls Brown Professor of Anatomy at Northeast Ohio Medical University. He is the author of The Walking Whales: From Land to Water in Eight Million Years. |
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Thumper It means not very, other than none closer. In this case, the common relative of whales and hippos goes back some 50 million years and and it did not look at all like a hippo or a whale. Fossil evidence indicates that a nimble, cat-sized, deer-like mammal called Indohyus is even more closely related to whales. It is possible that both cetaceans and hippos are derived from Indohyus or a similar species. Indohyus lived near the northern edge of the Indian subcontinent at a time when the Himalayas were just forming, and the Tethys Sea separated the Indian and Asian land masses. It is here that cetaceans originated. |
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@zorroloco But I am a little concerned about this discussion becoming unfocused. I could post rebuttal articles to the articles you posted (I’ve already found two from Googling) but would prefer to have a conversation. And without the foundation of an agreed-upon definition of transitional fossil, and whether claimed transitional fossils (in your articles and elsewhere) meet that definition, I don’t see any way forward. I stated what I consider to be a good definition of a transitional fossil, and would like to know if evolutionists agree with that, and, if not, how they would define it. On the horse, is a one-toed horse of the same species as a three-toed horse? I’ve never denied that variations take place within a species; I just don’t think the accumulated variations within a species lead to an entirely separate species. Does this mean we need an agreed-upon definition of species? Maybe so. As far as I know, ability to reproduce with each other is a traditional definition of species. But I don’t know for certain that’s accurate or if there’s not more to the definition of species. |
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Vic (various) 1. <If there are two competing thoughts or ideas to explain a phenomena, and one idea has very little evidence and the other even less, I don’t think the idea with very little evidence should be considered a theory simply because it’s a better explanation than the second idea. I think the only response to the phenomena should be, “We don’t know” and to wait for someone to propose a more credible idea.> This is wrong, both in fact and in principle. Wrong in fact because there is a vast amount of evidence which fits the evolutionary paradigm, specially in genetics as well as the better-known fossil approach. And wrong in principle because science works by proposing a hypothesis and then testing it against observations. Science does NOT work by waiting until all the facts are in, because all the facts are never in. Meanwhile, we need something to give direction to research, to either test the predictions of the hypothesis or to disprove them. You say "I don’t believe the theory of evolution has the evidentiary support that you do", but that is your opinion, not data. My opinion is that there is a wealth of data, from many independent sources and disciplines, that converges on support for the theory, at least in broad outline. When it comes to differences of opinions, then weight should be given the consensus of those who have the best and deepest understanding of the data. If you don't agree, then do your own research (or support the research of others with your opinion) to find a better theory. It is interesting that your arguments are almost exclusively based on the fossil record, and even then ob the fossil record as it was know 50 or more years ago. you quote Darwin on this point, but no current archaeologists. You seem to have only the vaguest idea of current understanding on the subject, and in this regard you follow most of the Creationist arguments I have read in various books. You have not made yourself familiar with the theory you are challenging, but only the 'counter-arguments' put up by detractors. As for DNA and genetic evidence, Stal would be best able to answer any specific questions you might want to ask. But it would be unfair on anyone to simply say 'Prove it!' without first saying what you would accept as proof. 2. I note your Biblical references, but they carry no scientific weight. I'd be more than willing (eager, in fact!) to participate in a separate thread that examines these, in particular how 'Wisdom' is discussed in the Bible. It is a rich subject, specially Jesus telling his followers "be ye therefore wise as serpents" (Matt. 10:16). 3. Asymmetric arguments. For example, "Is there any discovery that would invalidate the theory of evolution? Because I think a scientific theory, to be valid, needs to be falsifiable." I agree with the principle you invoke, but you invoke it in a lop-sided way. The Theory of Evolution makes certain predictions, too many to list here. There are (according to your posts) thousands of competent scientists who disagree with the theory. All they need to do is show that one or more of those predictions is fundamentally irreconcilable with observations. So far it hasn't happened. The most that has been achieved is to correct minor errors in details. 4. Demanding perfection, when no science is ever perfect. <if data (like the Cambrian explosion or the complexity of cells and DNA) comes in that seems to contradict it, that doesn’t mean the central claim of the theory might be wrong? It just means the theory has to be changed to fit the new data?> You seem to think this is evolutionists 'cheating'. In fact, it is standard procedure in all sciences. As more data becomes available, the theory is modified to account for that data. If the new data shows that there is a fundamental flaw that can't be accommodated by improving the theory, then the hunt for a better fundamental theory starts. Nobody throws away a fundamentally sound understanding for the sake of an unexpected detail that can be made good. 5. Demanding a level of evidence that is inherently impossible. Concerning the number of 'transitional fossils, you ask <And “millions” is pretty general as it could include any number between 2 million and umpteen number of millions. Could you narrow it down a little?> Well, how many would be enough to satisfy you? Even ONE should be enough to dismiss this objection! Would your original request for '5 or 10' such examples be enough? Zorro (9 Sept. 10:22) has given you a string of intermediate forms and you reply 'I'll check it out'. Does that mean you weren't aware of these? If you were, then why did you need them to be listed? 6. Poor definition. You do well in one sense, in that you provide your working definition as "In my view, a transitional fossil is a fossil dug from the earth that has visible (not conjectured) features that demonstrate it is an intermediary between two established species. The features that cause it to be considered a transitional fossil have to be visible and not the result of extrapolation by imagination." Although Zorro is right when he says "If evolutionary theory is accurate, all species are transitional as are all fossils", I'm happy to adopt your wording for the moment. In that case, the horse lineage provided by Zorro is one example, another would be the dinosaur-to-bird lineage represented by Archaeopteryx and several other winged-and-feathered species discovered since. But for some reason you seem to not acknowledge these as 'transitional'. Please, Vic; if you think the Theory of Evolution has insufficient evidence, that's fine. But if you want to go further and dismiss the evidence that has been presented, then please do so on scientifically-acceptable grounds. Or better still, come up with another theory that provides a better explanation for that evidence. That's how Science works. |
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Vic 16:37 An excellent point! The whole concept of 'species' is a convenience for study, and not a clear and strict transfer from the real world. The ability to inter-breed has long been the 'accepted' but somewhat simplified definition, but interbreeding has occurred between separate species of big cats and different equine species. There is even strong evidence of interbreeding between modern humans and other species such as Neanderthals and Denisovans. This means that the standard Creationist emphasis on 'each according to its own kind ('min')' requires the word 'kind' to mean a higher classification than 'species'. Perhaps 'genus', but this would seem too broad. As far as I have read, there is no agreed Creationist taxonomy, which I see as one of the weaknesses of traditional Creationism. But whatever 'min' might mean, it is clear that hippos and whales tend not to interbreed. Yet there is a strong chain of not only fossils connecting them, but more importantly fetal development milestones and genetic tracers between these distinct genera. I have yet to see a Creationist theory that can account for this in a way that can be tested. |
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This is sadly typical of the sort of insults that evolutionists resort to when anyone questions or challenges their theory. <<Let me list a few points that lead me to think that... <<<1. <If there are two competing thoughts or ideas to explain a phenomena, and one idea has very little evidence and the other even less, I don’t think the idea with very little evidence should be considered a theory simply because it’s a better explanation than the second idea. I think the only response to the phenomena should be, “We don’t know” and to wait for someone to propose a more credible idea.>>> <<This is wrong, both in fact and in principle. Wrong in fact because there is a vast amount of evidence which fits the evolutionary paradigm,>> I disagree that a “vast amount of evidence” exists for the theory of evolution, but what I wrote was meant to serve as an example of why I disagree with the idea of having a placeholder theory until a better theory comes along. It’s Ok for atheists and agnostics to say, “We don’t know.” <<specially in genetics as well as the better-known fossil approach.>> Feel free to present it. <<And wrong in principle because science works by proposing a hypothesis and then testing it against observations.>> Ok. What observations have been done that demonstrate random mutations and natural selection lead to the creation of new species? In the long-running bacteria and fruit fly experiments, Darwin’s central claim failed. <<Science does NOT work by waiting until all the facts are in, because all the facts are never in. Meanwhile, we need something to give direction to research, to either test the predictions of the hypothesis or to disprove them.>> Ok. What tests have been done that demonstrate one species turns into another species? I’m not talking about variation within a species. I’m talking about one species becoming a different species. As I said earlier, I realize time does not allow for that hypothesis to be tested and confirmed, notwithstanding the failed bacteria and fruit fly experiments. <<You say "I don’t believe the theory of evolution has the evidentiary support that you do", but that is your opinion, not data.>> Yes, that is my opinion. <<My opinion is that there is a wealth of data, from many independent sources and disciplines, that converges on support for the theory, at least in broad outline.>> Ok, well what is it? We’re getting nowhere with the fossil record because no evolutionist apparently wants to define a transitional fossil or say how many exist. <<When it comes to differences of opinions, then weight should be given the consensus of those who have the best and deepest understanding of the data. If you don't agree, then do your own research (or support the research of others with your opinion) to find a better theory.>> What’s true and what’s false is not determined by a popularity contest (remember how everyone at one time didn’t realize the earth revolves around the sun?) especially when scientists have a vested interest in a theory being true and who stifle dissent and challenges to that theory. <<It is interesting that your arguments are almost exclusively based on the fossil record,>> That was my starting off point. I’d rather settle the discussion on that and then move onto something else than have multiple topics being debated at the same time. <<and even then ob the fossil record as it was know 50 or more years ago. you quote Darwin on this point, but no current archaeologists.>> My point in the Darwin quote was to show that he, as the author of the theory of evolution, believed the number of transitional fossils was important. <<You seem to have only the vaguest idea of current understanding on the subject,>> Another insult and typical of evolutionists when their theory is challenged (or even questioned.) <<and in this regard you follow most of the Creationist arguments I have read in various books. You have not made yourself familiar with the theory you are challenging, but only the 'counter-arguments' put up by detractors.>> It’s not my job to present evidence for the theory of evolution. That’s what evolutionists are supposed to do. And then skeptics ask questions about the evidence they’ve presented. So far, I’ve asked two - what is the evolutionists’ definition of a transitional fossil, to which I have not received a reply, and what is the number of transitional fossils, to which I received one reply - “millions,” which could be anywhere from 2 million to 900 million. To be continued… |
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He should first present the evidence. Why should I both present the evidence and then seek to challenge it. <<But it would be unfair on anyone to simply say 'Prove it!' without first saying what you would accept as proof.>> I’m not asking for proof. I’m asking for evidence. If stalhandske is s familiar with DNA and genetic evidence for the theory of evolution, he can certainly present a summary. You guys wanted to have this debate, not me. Why am I supposed to do all the work? <<2. I note your Biblical references, but they carry no scientific weight.>> The words of Jesus Christ and the man He commissioned to bring His gospel to the Gentiles carry no weight? <<I'd be more than willing (eager, in fact!) to participate in a separate thread that examines these, in particular how 'Wisdom' is discussed in the Bible. It is a rich subject, specially Jesus telling his followers "be ye therefore wise as serpents" (Matt. 10:16).>> In that verse, Jesus was telling His followers how to relate to the world (non-Christians) not to Himself, God the Father and fellow Christians. I’m sure you would agree God the Father, Jesus Christ and Christians are an entirely separate group, from a spiritual standpoint, than the world. The verses I cited pertain to how Christians relate to God the Farher. <<3. Asymmetric arguments. For example, <<<"Is there any discovery that would invalidate the theory of evolution? Because I think a scientific theory, to be valid, needs to be falsifiable.">>> >> <<I agree with the principle you invoke, but you invoke it in a lop-sided way. The Theory of Evolution makes certain predictions, too many to list here. There are (according to your posts) thousands of competent scientists who disagree with the theory. All they need to do is show that one or more of those predictions is fundamentally irreconcilable with observations. So far it hasn't happened. The most that has been achieved is to correct minor errors in details.>> Do you honestly think the Cambrian explosion is “a minor error in details?” Did Darwin’s theory predict it? And what predictions did Darwin’s theory make that have been verified? <<4. Demanding perfection, when no science is ever perfect.>> I don’t demand perfection. I would like to see evidence. <<<if data (like the Cambrian explosion or the complexity of cells and DNA) comes in that seems to contradict it, that doesn’t mean the central claim of the theory might be wrong? It just means the theory has to be changed to fit the new data?>>> <<You seem to think this is evolutionists 'cheating'>> No, I think it’s evolutionists clinging to an increasingly discredited theory. <<In fact, it is standard procedure in all sciences. As more data becomes available, the theory is modified to account for that data.>> Not when the central belief of that theory was never verified. <<If the new data shows that there is a fundamental flaw that can't be accommodated by improving the theory, then the hunt for a better fundamental theory starts.>> And what possible data, to an evolutionist, could reveal a fundamental flaw with the theory of evolution? Can you honestly imagine anything? <<Nobody throws away a fundamentally sound understanding for the sake of an unexpected detail that can be made good.>> The Cambrian explosion is an unexpected detail? I could cite others, but let’s start there. |
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<<Well, how many would be enough to satisfy you? Even ONE should be enough to dismiss this objection!>> Really? Just one? You don’t know about harmful mutations and deformities? <<Would your original request for '5 or 10' such examples be enough?>> It depends on how a transitional fossil is defined. Is the evidence of a “transitional fossil” visible on the fossil or is it the result of conjecture? Is the “transitional fossil” really a variation between two species or does it represent a variation within a single species? <<Zorro (9 Sept. 10:22) has given you a string of intermediate forms and you reply 'I'll check it out'. Does that mean you weren't aware of these? If you were, then why did you need them to be listed?>>> It means I wanted to see why they were classified as intermediate forms (transitional fossils) - if the classification was the result of something visible or conjecture. <<6. Poor definition. You do well in one sense, in that you provide your working definition as "In my view, a transitional fossil is a fossil dug from the earth that has visible (not conjectured) features that demonstrate it is an intermediary between two established species. The features that cause it to be considered a transitional fossil have to be visible and not the result of extrapolation by imagination." Although Zorro is right when he says "If evolutionary theory is accurate, all species are transitional as are all fossils", I'm happy to adopt your wording for the moment. In that case, the horse lineage provided by Zorro is one example,>> You think a one-toed horse and three-toed horse are different species? <<another would be the dinosaur-to-bird lineage represented by Archaeopteryx and several other winged-and-feathered species discovered since. But for some reason you seem to not acknowledge these as 'transitional'.>> I haven’t said one way or another on Archaeopteryx. I’d like to look into it. <<Please, Vic; if you think the Theory of Evolution has insufficient evidence, that's fine. But if you want to go further and dismiss the evidence that has been presented, then please do so on scientifically-acceptable grounds.>> I’m asking questions, Bob. Why is asking for a mutually-agreed-upon definition of “transitional fossil” and how many transitional fossils exist so objectionable? Seriously. Why is asking for a mutually-agreed-upon definition of transitional fossil and how many transitional fossils exist so objectionable? <<Or better still, come up with another theory that provides a better explanation for that evidence. That's how Science works.>> I believe the creation account in Genesis for the reasons I stated in an earlier post. But no, I don’t think it can be scientifically proven - just like Darwin’s theory can’t be scientifically proven. Evolutionists, imo, have as much faith (if not more faith) in Darwin than creationists have in God and believing the early chapters in Genesis. |
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Vic and Thumper I must have an exceptionally thick skin, but I don't see any 'insults' in what I posted. I said your answers weer evasive, because they did not address the principle issues. Where have you even attempted to consider fetal development and genetic evidence? Where have you even met the challenge on fossil evidence, your apparent strong point, in the equine and avian chains mentioned? You have evaded those points. As for positive statements which experts find very convincing, you simply wave them away if you disagree with them. You tell me to 'present the evidence'. Zorro and I have done that. Admittedly not comprehensively, because that would take libraries; but even in so far as we have suggested lines of enquiry, you have not followed them. What is the point of anyone presenting evidence, if you are not going to consider it objectively? I have read extensively in Creationist literature, by which I mean literature actively advocating anti-evolutionary themes and widely recognised by organisations such as Creation Science Research Center. I do NOT rely on what their detractors say that they said. And I have no personal interest in proving them wrong; in fact, it would be much more satisfying to me, as a Christian, if they could present a sound case. But they don't. <Do you honestly think the Cambrian explosion is “a minor error in details?” Did Darwin’s theory predict it?> The 'Cambrian explosion' is not a counter-example to Evolutionist thinking, but an example of it. Once animal life developed mobility, there was a plenitude of environmental niches to be filled, and competition to fill them. Exactly what the evolutionary paradigm says would happen. The same applies with the other great extinction events in the geologic record; they are followed by a rapid diversification of species arising from the survivors of the extinction. <Did Darwin's theory predict it?> You are still talking as if evolutionary thinking is stuck in the 19th century, and limited to what Darwin said. Darwin himself didn't have the data to predict the Cambrian explosion, but he gathered the data to demonstrate speciation in different environmental niches in the Galapagos Islands. Since then there has been a wealth of further data, the most recent wave of it being genetic/developmental; but you seem to not be familiar with that. Read up on it from experts, rather than relying on posts in chat clubs. <And what possible data, to an evolutionist, could reveal a fundamental flaw with the theory of evolution? Can you honestly imagine anything?> Were we to discover complex life on another planet, or the remains of extinct complex life on another planet, which starts suddenly with no sign of progenitor life, that would be very strong evidence that some form of Creationism can take place. I don't expect it to happen, but if it does, we will need to re-examine ALL the data in the light of those new discoveries; not just throw out the data we have and replace it. This brings up the interesting but associated point that we DON'T see complex life appearing suddenly on Earth. If Creationism is correct, then why didn't mammals appear as part of the Cambrian Explosion? That would appear to be data the reveals a fundamental flaw in Creationism. I have read one theory that says the layering of fossils represents the settling of debris from Noah's Flood, with the big, heavy dinosaurs at the bottom because they settle out first, and lighter mammals on top. That doesn't explain why the lightest fossils of all, such as corals, invertebrates , insects, etc are in the most ancient rocks and whales and mammoths are in the most recent rocks. There are other obvious flaws, fatal flaws, in Creationist stratigraphy that I would be happy to explain if you express some inclination to put a serious effort into reading and understanding a semi-technical explanation of soil mechanics. <The words of Jesus Christ and the man He commissioned to bring His gospel to the Gentiles carry no weight?> They carry no weight when it comes to Science, because he was not trying to instruct us on Science. In the same way, a calendar carries authority when I want to see what day it is, but carries no weight if I want to know the time of day. That is the biggest single problem with Creationist claims; they try to read the Bible as if a science textbook that will never need to be updated, but demand that Science gives answers with 'religious' certainty. They have no understanding of GENRE. The rest of your two most recent posts (18:37 and 18:55) are little more than simple contradictions, assertions without evidence. Thumper, you make a good point. I have already agreed that taxonomic divisions such as 'species' do not accurately reflect the reality out there. The question is not one of 'yes' or 'no', but 'how far apart' and 'what are the consequences'. |
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Vic 19:17 <I’m asking questions, Bob. Why is asking for a mutually-agreed-upon definition of “transitional fossil” and how many transitional fossils exist so objectionable?> I've agreed to your definition of a 'transitional fossil' for the purposes of this discussion. I don't 'object' to you asking how many 'transitional fossils' there are, but point out that 'transitional' will inevitably be limited to the discoveries to date, a number that will continue to increase. Also, 'transitional' inherently involves a continuum, so there will always be room for arguing whether two closely-related fossils are within the range of one 'species' or not. What I object to is the implication in your response to Voci that a million transitional fossils is an insufficient number to demonstrate that transitional fossil exist. That is why I asked how many would be sufficient to convince you, a question that you still have not answered. As I said earlier, Science is not about 'proof'. No scientific theory is ever going to be 100% 'proven'. We have to be content with the best fit available, while also recognising the wisdom of making prudent allowance for inaccuracies and errors to be corrected as better data becomes available. |
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Bob |
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stalhandske 09-Sep-22, 20:55 |
Transitional fossils The start of the discussion on evolution was this time spurred by Vic's important point of 'transitional fossils' - why there are so few (if any) of them. As noted, this was a deep concern already by Darwin, long before there was understanding of the molecuar genetics that determines species. So, I thought it be a proper response to summarise (by a very general wikipedia article) what the situation is with regard to this issue. Unfortunately, this discussion has now degraded into new requests of defining 'transitional fossils'. It seems to me that creationists require the finding of a 'hippo-whale' or the equivalent for other species. They do not seem to understand the very nature of the (proposed) evolutionary process. Or may be they do, but won't accept that possibility? |
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Number of Transitionals How many birds are there? If no one knows the answer to this question, is it safe to assume birds are not real? en.wikipedia.org Here is the page on vertebrate transitions: www.talkorigins.org We also have long lists of transitional species in many other categories. You can kind of see the interrelationships between all living organisms in "The Tree of Life." simple.wikipedia.org) From 590 to 500 million years ago (Cambrian) the only fish in the ocean were jawless fishes. There were not sharks, lampreys, eels, etc. The earliest ray finned and lobe finned fishes don't appear until the Silurian, 440 to 400 million years ago. Fish dominate the oceans in the Devonian, by the end of which we find the oldest fossils of amphibians. At this time there are no frogs, salamanders, or ANY modern amphibian--only the most primitive, fish-like forms. As for sharks, I'm lifting this straight from the talk.origins page: Cladoselache (late Devonian) -- Magnificent early shark fossils, found in Cleveland roadcuts during the construction of the U.S. interstate highways. Probably not directly ancestral to sharks, but gives a remarkable picture of general early shark anatomy, down to the muscle fibers! Tristychius & similar hybodonts (early Mississippian) -- Primitive proto-sharks with broad-based but otherwise shark-like fins. Ctenacanthus & similar ctenacanthids (late Devonian) -- Primitive, slow sharks with broad-based shark-like fins & fin spines. Probably ancestral to all modern sharks, skates, and rays. Fragmentary fin spines (Triassic) -- from more advanced sharks. Paleospinax (early Jurassic) -- More advanced features such as detached upper jaw, but retains primitive ctenacanthid features such as two dorsal spines, primitive teeth, etc. Spathobatis (late Jurassic) -- First proto-ray. Protospinax (late Jurassic) -- A very early shark/skate. After this, first heterodonts, hexanchids, & nurse sharks appear (late Jurassic). Other shark groups date from the Cretaceous or Eocene. First true skates known from Upper Cretaceous. These are all vertebrate transitions. From aquatic fish to the earliest transitional amphibians: Paleoniscoids again (e.g. Cheirolepis) -- These ancient bony fish probably gave rise both to modern ray-finned fish (mentioned above), and also to the lobe-finned fish. Osteolepis (mid-Devonian) -- One of the earliest crossopterygian lobe-finned fishes, still sharing some characters with the lungfish (the other lobe-finned fishes). Had paired fins with a leg-like arrangement of major limb bones, capable of flexing at the "elbow", and had an early-amphibian-like skull and teeth. Eusthenopteron, Sterropterygion (mid-late Devonian) -- Early rhipidistian lobe-finned fish roughly intermediate between early crossopterygian fish and the earliest amphibians. Eusthenopteron is best known, from an unusually complete fossil first found in 1881. Skull very amphibian-like. Strong amphibian- like backbone. Fins very like early amphibian feet in the overall layout of the major bones, muscle attachments, and bone processes, with tetrapod-like tetrahedral humerus, and tetrapod-like elbow and knee joints. But there are no perceptible "toes", just a set of identical fin rays. Body & skull proportions rather fishlike. Panderichthys, Elpistostege (mid-late Devonian, about 370 Ma) -- These "panderichthyids" are very tetrapod-like lobe-finned fish. Unlike Eusthenopteron, these fish actually look like tetrapods in overall proportions (flattened bodies, dorsally placed orbits, frontal bones! in the skull, straight tails, etc.) and have remarkably foot-like fins. Fragmented limbs and teeth from the middle Late Devonian (about 370 Ma), possibly belonging to Obruchevichthys -- Discovered in 1991 in Scotland, these are the earliest known tetrapod remains. The humerus is mostly tetrapod-like but retains some fish features. The discoverer, Ahlberg (1991), said: "It [the humerus] is more tetrapod-like than any fish humerus, but lacks the characteristic early tetrapod 'L-shape'...this seems to be a primitive, fish-like character....although the tibia clearly belongs to a leg, the humerus differs enough from the early tetrapod pattern to make it uncertain whether the appendage carried digits or a fin. At first sight the combination of two such extremities in the same animal seems highly unlikely on functional grounds. If, however, tetrapod limbs evolved for aquatic rather than terrestrial locomotion, as recently suggested, such a morphology might be perfectly workable." GAP: Ideally, of course, we want an entire skeleton from the middle Late Devonian, not just limb fragments. Nobody's found one yet. Hynerpeton, Acanthostega, and Ichthyostega (late Devonian) -- A little later, the fin-to-foot transition was almost complete, and we have a set of early tetrapod fossils that clearly did have feet. The most complete are Ichthyostega, Acanthostega gunnari, and the newly described Hynerpeton bassetti (Daeschler et al., 1994). (There are also other genera known from more fragmentary fossils.) Hynerpeton is the earliest of these three genera (365 Ma), but is more advanced in some ways; the other two genera retained more fish- like characters longer than the Hynerpeton lineage did. Labyrinthodonts (eg Pholidogaster, Pteroplax) (late Dev./early Miss.) -- These larger amphibians still have some icthyostegid fish features, such as skull bone patterns, labyrinthine tooth dentine, presence & pattern of large palatal tusks, the fish skull hinge, pieces of gill structure between cheek & shoulder, and the vertebral structure. But they have lost several other fish features: the fin rays in the tail are gone, the vertebrae are stronger and interlocking, the nasal passage for air intake is well defined, etc. Now I have a question. Suppose I created all life forms simultaneously and wanted mankind to know my divine truth. Why would I bury long extinct forms so incredibly evocative of gradual evolutionary change in ancient strata, in the sequence dictated by evolutionary science postulating a marine origin for metazoans? If the word "evasive" is insulting, I know you will happily tackle this question directly, just as I am delighted to answer any question you posit. |
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Stål |
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Ruling I prefer to not hear claims that evolutionists are dishonest or that creationists are ignorant--anything of that nature. While I will permit such posts for now, let us strive to defer to each other's sensibilities. Our goal is not to persuade anyone of anything, but simply to achieve a mutual understanding. And as a reminder--"evolutionists are dishonest" will stand, but "creationists are ignorant" will be cause for censorship. I'm standing firmly behind that double standard. |
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Force Fed Facts Speaking of the Flat Earth, where is Frank when you need him? |
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Force fed Hmmmm…. |
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stalhandske 09-Sep-22, 21:36 |
Thumper I don't really know, of course, but I don't think you have been force fed. You have (presumably) just been given the information available to science at the time. |
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Transitional Fossils Ok, if Thumper doesn't get a chuckle out of that I"m hanging up my comedian hat. So how can we tell if two fossilized specimens were capable of interbreeding or not? I think it is pretty safe to say that if two specimens are separated by a few million years, they could not interbreed--the same reason none of us can interbreed with an ancestor who passed on ten generations back. That may not make them separate species, but the key question here is the gradual transition of all life on Earth from the seas to the land, and the continued changes within both biomes. How many species that exist today are nearly indistinguishable from creatures that lived in the mid Cretaceous, a hundred million years ago? Mosquitoes. Those are pretty much the same. Sharks. Crocodiles. Ants and bees are known from a hundred million years ago, but not a whole lot more than that. I list these because it is far easier than listing rhinos, kangaroos, wallabies, eagles, bats, crows, pigeons, humming birds, skinks (the oldest known skink is a 25 million year old specimen found in the Australian outback, Proegernia mikebulli, Bob), mountain lions, moose (had two in my front yard yesterday), caterpillars, lemmings, wolverines, walruses, penguins, bears, bandersnoots, aardvarks, elephants, parrots, badgers, pythons, buffalo, canaries, camels, cheetahs, doves, deer, dandelions, emus, ferrets, falcons, finches (even Galapagos Island finches), gerbils, pandas, gnus, geese, grouse, sage hen, rabbits, hedgehogs, herons, hyenas, horses, jaguars, kites, koalas, lemurs, and the like. The beauty of the tree of life is how it delineates the interconnections between the species. Linnaeus recognized organisms could be classified, and produced a great scheme for doing so--he simply failed to take that one further step that became so obvious to Darwin. |
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Force fed Hmmmm.... |
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bobspringett 09-Sep-22, 21:48 |
Deleted by bobspringett on 09-Sep-22, 21:54.
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