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New Bird/Dinosaur intermediate species found

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  • #46
    Originally posted by lee_merrill
    Certainly, though in the case of the Cambrian explosion, the fossil record should show some intermediates--only it doesn't.
    Originally posted by lee_merrill
    I have read of the pre-Cambrian, and any intermediates (that I have seen) are speculative.
    I don't think you've actually looked at the fossil record of the pre-Cambrian. I think you've merely read creationist/ID summaries of it, and swallowed them wholesale.
    Jorge: Functional Complex Information is INFORMATION that is complex and functional.

    MM: First of all, the Bible is a fixed document.
    MM on covid-19: We're talking about an illness with a better than 99.9% rate of survival.

    seer: I believe that so called 'compassion' [for starving Palestinian kids] maybe a cover for anti Semitism, ...

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    • #47
      Originally posted by shunyadragon View Post
      Your latest problem is incompletely citing a source: Fossil Museum?, a brief sound bite without a recognizable scientific reference nor credibility of context.

      What is your reference: Fossil Museum?
      It's from here. Easy to find because of the spelling error.

      But Dory's use of it is fallacious anyway. Just because trilobite and early arthropod ancestry is unresolved doesn't mean there aren't any intermediate fossils. It means that there are multiple potential intermediates, and we can't be sure which ones are the actual intermediates.

      This section from the article Dory claims to have read does contradict his earlier claim that there are no intermediates in the Cambrian explosion fossil record:
      The Naraoiidae is a family of early arthropods resembling trilobites in appearance. Because Naraoids had an entirely non-mineralized exoskeletons, they are often referred to as soft-bodied trilobites.
      as does the phylogenetic tree there and the pictures of naraoiids and helmetiids. I expect him to keep claiming there are no intermediates anyway.
      Last edited by Roy; 03-07-2019, 04:23 AM.
      Jorge: Functional Complex Information is INFORMATION that is complex and functional.

      MM: First of all, the Bible is a fixed document.
      MM on covid-19: We're talking about an illness with a better than 99.9% rate of survival.

      seer: I believe that so called 'compassion' [for starving Palestinian kids] maybe a cover for anti Semitism, ...

      Comment


      • #48
        Adding to the mix:

        Source: SPRIGGINA IS A TRILOBITOID ECDYSOZOAN


        Convincingly specific homologies between Ediacarans and members of recognized animal phyla have remained elusive, thus casting a shadow of doubt over the animal affinity interpretation of Ediacaran phylogeny. Spriggina floundersi, for example, has been described as a tomopterid annelid, an arthropod, and a frondose vendobiont. Reanalysis of Spriggina demonstrates the presence of genal spines (comparable to those of fallotaspidoid and paradoxidid trilobites), a cephalic region homologous to the effaced cephalons of agraulid and skehanid trilobites, and a dual cephalic region (also seen in Parvancorina) that compares to the parts of a trilobite cephalon anterior and posterior of the facial suture. Spriggina is thus a trilobitoid ecdysozoan, a conclusion in accord with Sven Jorgen Birket-Smith�s inference of an arthropod affinity for Spriggina. This result is among the first confident phylogenetic linkages between an Ediacaran and a Cambrian animal, and thus helps to demonstrate that Paleozoic animals could indeed be descended from Ediacarans. If Spriggina is a direct ancestor of trilobites, then a case can be made that Spriggina itself (or a direct descendant) served as the predator taxon that initiated the Cambrian ecotone transformation (McMenamin, M. A. S., 2003, Origin and early evolution of predators: The ecotone model and early evidence for macropredation. In: P. Kelley, M. Kowalewski and T. Hansen, eds., Predator-Prey Interactions in the Fossil Record). Such heterotrophy, however, does not preclude the possibility of photosymbiosis or other types of mixotrophy in Ediacarans with high surface area such as Marywadea and Dickinsonia.


        Source

        © Copyright Original Source




        Sam 'Ohu Gon III a paleobiologist at the University of Hawaii at Manoa has an informative webpage Origins of Trilobites from which the following comes from

        Parvancorina: a Precambrian trilobite ancestor?
        00000000000000ab000-01c.jpg
        Parvancorina michami (left), Primicaris larvaformis (center), trilobite protaspis (right)

        The similarity of the Precambrian Parvancorina to the Cambrian Chengjiang arthropod Primicaris larvaformis, and a protaspid of a Cambrian trilobite is seen to the left[1]. All three have an ovoid form, and an anchor-like structure made up of an axial lobe and lateral lobes running along the anterior and lateral edges of the body. Primicaris was first thought to be a larval naraoid (e.g., Hou & Bergstrom 1997), but it was recognized more recently as taxon in its own right (Zhang et al 2003). Recapitulating phylogeny, the trilobite protaspid resembles Primicaris. If the similarity of Parvancorina to Primicaris is more than superficial, it is perhaps the best candidate for an early arthropod in the Precambrian.


        He also has this explanatory illustration

        From Parvancorina to Trilobite in Four Easy Steps:
        00000000000000a00a.gif


        Personally, I agree that the link is still tentative but it is more than sufficient to demonstrate that there is no evidence of intermediaries is hogswallop.

        For a bit more on potential intermediates from Precambrian to Cambrian organisms

        Source: A Parvancorina-like arthropod from the Cambrian of South China


        AbstractSkania, which bears an exoskeleton that shares homologies with the Neoproterozoic (Ediacaran) organism ParvancorinaSkania and related genera represents a step in the progression toward division of a cephalon from a large posterior trunk as shown in Cambrian arachnomorphs such as naraoiids and the addition of a pygidium and thoracic tergites as shown in the arachnomorph clade basal to trilobites. This evidence can serve as a new calibration point for estimating the divergence time for the last common ancestor of arthropods and priapulids based on molecular clock methods.


        Source

        © Copyright Original Source







        1 I moved the illustration from the left to above in this post
        Last edited by rogue06; 03-07-2019, 05:56 AM.

        I'm always still in trouble again

        "You're by far the worst poster on TWeb" and "TWeb's biggest liar" --starlight (the guy who says Stalin was a right-winger)
        "Overall I would rate the withdrawal from Afghanistan as by far the best thing Biden's done" --Starlight
        "Of course, human life begins at fertilization that’s not the argument." --Tassman

        Comment


        • #49
          Originally posted by Roy View Post
          It's from here. Easy to find because of the spelling error.

          But Dory's use of it is fallacious anyway. Just because trilobite and early arthropod ancestry is unresolved doesn't mean there aren't any intermediate fossils. It means that there are multiple potential intermediates, and we can't be sure which ones are the actual intermediates.

          This section from the article Dory claims to have read does contradict his earlier claim that there are no intermediates in the Cambrian explosion fossil record:
          The Naraoiidae is a family of early arthropods resembling trilobites in appearance. Because Naraoids had an entirely non-mineralized exoskeletons, they are often referred to as soft-bodied trilobites.
          as does the phylogenetic tree there and the pictures of naraoiids and helmetiids. I expect him to keep claiming there are no intermediates anyway.
          Thank you for putting the reference in context. The reference is good, but more a summary of the present classification based on the fossil evidence.

          This is a classic Lee's habit of using out of context 'sound bites' to justify his agenda that do not reflect the whole reference, nor in context of the overall knowledge of the overall evolution in the given period of time. This reflects an out of context 'argument from ignorance.' and a reflection of Lee's lack of knowledge.

          Comment


          • #50
            Originally posted by shunyadragon View Post
            This is a classic Lee's habit of using out of context 'sound bites' to justify his agenda that do not reflect the whole reference, nor in context of the overall knowledge of the overall evolution in the given period of time. This reflects an out of context 'argument from ignorance.' and a reflection of Lee's lack of knowledge.
            Lack of knowledge isn't the problem. Lack of awareness of lack of knowledge isn't even the problem. Lack of willingness to remedy lack of knowledge is the problem.
            Jorge: Functional Complex Information is INFORMATION that is complex and functional.

            MM: First of all, the Bible is a fixed document.
            MM on covid-19: We're talking about an illness with a better than 99.9% rate of survival.

            seer: I believe that so called 'compassion' [for starving Palestinian kids] maybe a cover for anti Semitism, ...

            Comment


            • #51
              Originally posted by rogue06 View Post
              For a bit more on potential intermediates from Precambrian to Cambrian organisms

              Source: A Parvancorina-like arthropod from the Cambrian of South China


              AbstractSkania, which bears an exoskeleton that shares homologies with the Neoproterozoic (Ediacaran) organism ParvancorinaSkania and related genera represents a step in the progression toward division of a cephalon from a large posterior trunk as shown in Cambrian arachnomorphs such as naraoiids and the addition of a pygidium and thoracic tergites as shown in the arachnomorph clade basal to trilobites. This evidence can serve as a new calibration point for estimating the divergence time for the last common ancestor of arthropods and priapulids based on molecular clock methods.


              Source

              © Copyright Original Source

              Yet we read here:

              Source: Ediacaran.org

              Parvancorina, from the Latin parva ancora (small anchor), was a small anchor-shaped organism that lived on the Ediacaran seafloor. Parvancorina has been suggested to be an ancestor of living arthropods (the group that includes modern crabs, shrimp and insects), however its phylogenetic placement is uncertain at present.


              Source

              © Copyright Original Source


              Blessings,
              Lee
              "What I pray of you is, to keep your eye upon Him, for that is everything. Do you say, 'How am I to keep my eye on Him?' I reply, keep your eye off everything else, and you will soon see Him. All depends on the eye of faith being kept on Him. How simple it is!" (J.B. Stoney)

              Comment


              • #52
                Originally posted by lee_merrill View Post
                Yet we read here:

                Source: Ediacaran.org

                Parvancorina, from the Latin parva ancora (small anchor), was a small anchor-shaped organism that lived on the Ediacaran seafloor. Parvancorina has been suggested to be an ancestor of living arthropods (the group that includes modern crabs, shrimp and insects), however its phylogenetic placement is uncertain at present.


                Source

                © Copyright Original Source


                Blessings,
                Lee
                As I noted:

                Personally, I agree that the link is still tentative but it is more than sufficient to demonstrate that there is no evidence of intermediaries is hogswallop.

                [*Emphasis added*]

                I'm always still in trouble again

                "You're by far the worst poster on TWeb" and "TWeb's biggest liar" --starlight (the guy who says Stalin was a right-winger)
                "Overall I would rate the withdrawal from Afghanistan as by far the best thing Biden's done" --Starlight
                "Of course, human life begins at fertilization that’s not the argument." --Tassman

                Comment


                • #53
                  Originally posted by lee_merrill View Post
                  Yet we read here:

                  Source: Ediacaran.org

                  Parvancorina, from the Latin parva ancora (small anchor), was a small anchor-shaped organism that lived on the Ediacaran seafloor. Parvancorina has been suggested to be an ancestor of living arthropods (the group that includes modern crabs, shrimp and insects), however its phylogenetic placement is uncertain at present.


                  Source

                  © Copyright Original Source


                  Blessings,
                  Lee
                  What is wrong with ' phylogenetic placement is uncertain at present'? Are you proposing your SOP selective 'arguing from ignorance.'

                  Comment


                  • #54
                    Another dinosaur bird intermediate found in the raptor family.

                    Source: https://news.nationalgeographic.com/2015/09/150905-animals-sleep-science-dreaming-cats-brains/



                    Meet Lori, a tiny dinosaur that may help explain how birds evolved flight

                    © Copyright Original Source

                    Comment


                    • #55
                      A bony toothed bird 62 million years old is another link between feathered flying dinosaurs and birds.

                      Source: http://www.sci-news.com/paleontology/protodontopteryx-ruthae-07603.html



                      Dubbed Protodontopteryx ruthae, the ancient seabird belongs to Pelagornithidae, an ancient family of bony-toothed birds.

                      © Copyright Original Source

                      Comment


                      • #56
                        Another discovery of an intermediate between Avian dinosaurs and birds found.

                        Source: https://www.smithsonianmag.com/science-nature/newly-discovered-fossil-bird-fills-gap-between-dinosaurs-and-modern-fliers-180973551/



                        Newly Discovered Fossil Bird Fills in Gap Between Dinosaurs and Modern Fliers

                        A skeleton from the Cretaceous found in Japan reveals an early bird with a tail nub resembling the avians of today
                        image: https://thumbs-prod.si-cdn.com/4goWk...eryx-prima.jpghttps://www.smithsonianmag.com/scien...t1MAOts3SHS.99
                        Give the gift of Smithsonian magazine for only $12! http://bit.ly/1cGUiGv

                        © Copyright Original Source

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                        • #57
                          Added note: These and other discoveries of avian dinosaurs and transitional species to birds and primitive birds existed in the Cretaceous forests. There is not only a progressive evolution in this time period, but also many variations existed in the forests at the same time.

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                          • #58
                            New discovery reveals an important advancement in the evolution of the beak in birds

                            Source: https://stockdailydish.com/scientists-make-new-discovery-about-bird-evolution/



                            Scientists make new discovery about bird evolution
                            Posted by SDD Contributor on December 15, 2019 at 8:50 am
                            Credit: CC0 Public Domain

                            In a new paper published in National Science Review, a team of scientists from the Institute of Vertebrate Paleontology and Paleoanthropology, the Shandong Tianyu Museum of Nature, and the Nanjing Institute of Geology and Paleontology (all in China) described the most exceptionally preserved fossil bird discovered to date.

                            The new specimen from the rich Early Cretaceous Jehol Biota (approximately 131 to 120 million years old) is referred to as Eoconfuciusornis, the oldest and most primitive member of the Confuciusornithiformes, a group of early characterized by the first occurrence of an avian beak. Its younger relative Confuciusornis is known from thousands of specimens but this is only the second specimen of Eoconfuciusornis found. This species comes only from the 130.7 Ma Huajiying Formation deposits in Hebei, which preserves the second oldest known fossil birds. Birds from this layer are very rare.

                            This new specimen of Eoconfuciusornis, housed in the Shandong Tianyu Museum of Nature, in Eastern China, is a female. The ovary reveals developing yolks that vary in size, similar to living birds. This suggests that confuciusornithiforms evolved a period of rapid yolk deposition prior to egg-laying (crocodilians, which are archosaurs like birds, deposit yolks slowly in all eggs for months with no period of rapid yolk formation), which is indicative of complex energetic profiles similar to those observed in birds.

                            © Copyright Original Source

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                            • #59
                              A beaked toothless flightless avian dinosaur with two toes found.

                              Source: https://scitechdaily.com/newly-discovered-toothless-two-fingered-dinosaurs-lost-digits-point-to-spread-of-parrot-like-species/



                              Newly Discovered Toothless, Two-Fingered Dinosaur’s Lost Digits Point to Spread of Parrot-Like Species

                              TOPICS:DinosaursEvolutionPaleontologyUniversity Of Edinburgh
                              By UNIVERSITY OF EDINBURGH OCTOBER 6, 2020

                              Three Oksoko avarsan dinosaurs. Credit: Michael W. Skrepnick

                              A newly discovered species of toothless, two-fingered dinosaur has shed light on how a group of parrot-like animals thrived more than 68 million years ago.

                              The unusual species had one less finger on each forearm than its close relatives, suggesting an adaptability which enabled the animals to spread during the Late Cretaceous Period, researchers say.

                              Multiple complete skeletons of the new species were unearthed in the Gobi Desert in Mongolia by a University of Edinburgh-led team.

                              Remains of three dinosaurs preserved resting together. Credit: Gregory Funston

                              Named Oksoko avarsan, the feathered, omnivorous creatures grew to around two meters long and had only two functional digits on each forearm. The animals had a large, toothless beak similar to the type seen in species of parrot today.

                              The remarkably well-preserved fossils provided the first evidence of digit loss in the three-fingered family of dinosaurs known as oviraptors.

                              The discovery that they could evolve forelimb adaptations suggests the group could alter their diets and lifestyles, and enabled them to diversify and multiply, the team says.

                              Researchers studied the reduction in size, and eventual loss, of a third finger across the oviraptors’ evolutionary history. The group’s arms and hands changed drastically in tandem with migrations to new geographic areas — specifically to what is now North America and the Gobi Desert.

                              Fossil of Oksoko avarsan’s two-fingered hand. Credit: Gregory Funston

                              The team also discovered that Oksoko avarsan — like many other prehistoric species — were social as juveniles. The fossil remains of four young dinosaurs were preserved resting together.

                              The study, published in the journal Royal Society Open Science, was funded by The Royal Society and the Natural Sciences and Engineering Council of Canada. It also involved researchers from the University of Alberta and Philip J. Currie Dinosaur Museum in Canada, Hokkaido University in Japan, and the Mongolian Academy of Sciences.

                              Dr. Gregory Funston, of the University of Edinburgh’s School of GeoSciences, who led the study, said: “Oksoko avarsan is interesting because the skeletons are very complete and the way they were preserved resting together shows that juveniles roamed together in groups. But more importantly, its two-fingered hand prompted us to look at the way the hand and forelimb changed throughout the evolution of oviraptors–which hadn’t been studied before. This revealed some unexpected trends that are a key piece in the puzzle of why oviraptors were so diverse before the extinction that killed the dinosaurs.”

                              © Copyright Original Source


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                              • #60
                                Another odd bird found in the Cretaceous adds to the diversity of evolving birds.

                                Source: https://phys.org/news/2020-11-bird-tall-sickle-shaped-beak-reveals.html




                                Bird with tall, sickle-shaped beak reveals hidden diversity during the age of dinosaurs


                                by Ohio University
                                Illustration depicting the early bird Falcatakely amidst nonavian dinosaurs and other creatures during the Late Cretaceous in Madagascar. Credit: Mark Witton.
                                A Cretaceous-age, crow-sized bird from Madagascar would have sliced its way through the air wielding a large, blade-like beak and offers important new insights on the evolution of face and beak shape in the Mesozoic forerunners of modern birds. An international team of researchers led by Ohio University professor Dr. Patrick O'Connor and Stony Brook University professor Dr. Alan H. Turner announced the discovery today in the journal Nature.

                                Birds have played a pivotal role in shaping our understanding of biological evolution. As long ago as the mid-19th Century, Charles Darwin's keen observations on the diversity of beak shape in Galapagos finches influenced his treatise on evolution through natural selection. This fossil bird discovery adds a new twist on the evolution of skulls and beaks in birds and their close relatives, showing that evolution can work through different developmental pathways to achieve similar head shapes in very distantly related animals.

                                The bird is named Falcatakely, a combination of Latin and Malagasy words inspired by the small size and the sickle-shaped beak, the latter representing a completely novel face shape in Mesozoic birds. The species is known from a single well-preserved, nearly complete skull, one that was buried in a muddy debris flow around 68 million years ago. Bird skeletons are rare in the fossil record because of their lightweight bones and small size. Bird skulls are an even rarer find. Falcatakely is the second Cretaceous bird species discovered in Madagascar by the National Science Foundation-funded team.

                                The delicate specimen remains partially embedded in rock due to the complex array of lightly built bones that make up the skull. Although quite small, with an estimated skull length of only 8.5 cm (~ 3 inches), the exquisite preservation reveals many important details. As one example, a complex series of grooves on the bones making up the side of the face indicate that the animal hosted an expansive keratinous covering, or beak, in life.
                                Play.

                                "As the face began to emerge from the rock, we knew that it was something very special, if not entirely unique," notes Patrick O'Connor, professor of anatomy and neuroscience at Ohio University and lead author on the study. "Mesozoic birds with such high, long faces are completely unknown, with Falcatakely providing a great opportunity to reconsider ideas around head and beak evolution in the lineage leading to modern birds."

                                Falcatakely belongs to an extinct group of birds called Enantiornithes, a group known exclusively from the Cretaceous Period and predominantly from fossils discovered in Asia. "Enantiornithines represent the first great diversification of early birds, occupying ecosystems alongside their non-avian relatives such as Velociraptor and Tyrannosaurus," says Turner, an associate professor of anatomical sciences at Stony Brook University and study co-author. "Unlike the first birds, such as Archaeopteryx, with long tails and primitive features in the skull, enantiornithines like Falcatakely would have looked relatively modern."

                                © Copyright Original Source



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