Announcement

Collapse

Natural Science 301 Guidelines

This is an open forum area for all members for discussions on all issues of science and origins. This area will and does get volatile at times, but we ask that it be kept to a dull roar, and moderators will intervene to keep the peace if necessary. This means obvious trolling and flaming that becomes a problem will be dealt with, and you might find yourself in the doghouse.

As usual, Tweb rules apply. If you haven't read them now would be a good time.

Forum Rules: Here
See more
See less

It's not a stretch to say this is a long neck

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • It's not a stretch to say this is a long neck

    A reanalysis of the fossilized remains of a sauropod unearthed in China in the 1980s is providing new insights into what is the longest necked group of sauropods known.

    The fossils were discovered in the red sandstone of the Shishugou Formation in northwest China in 1987 and consisted primarily of its mandible (lower jaw), skull fragments and a few vertebrae and dated to approximately 162mya (Late Jurassic). It was named Mamenchisaurus sinocanadorum with the genus name being an accidental misspelling with ménbeing mistaken for míngxī. The second or species name is in honor of the China–Canada Dinosaur Project team which discovered it.

    This genus appears to possess the longest necks of the sauropods (consisting of 50% of their total body length), with Mamenchisaurus sinocanadorum having the longest atnearly 50' in length which is some six times the length of that seen in giraffes and about one and a half times the length of a bus. Basically, it likely possessed the longest neck of any creature that ever lived.

    They discovered that one of the secrets for achieving this length was that the vertebrae, much like those seen in some long-necked bird species such as flamingos and swans, has numerous hollow air pockets, making them considerably lighter than those completely full of heavy marrow and tissue. The researchers estimate that these hollow portions accounted for up to 77% of the vertebrae's mass.

    A fossilized rod of bony tissue was found during the excavation might have been what is called a "cervical rib" that would have been a stiff extension of the vertebra acting like a brace but at the cost of some flexibility.

    In any case...


    Source: New fossil analysis reveals dinosaur with the longest neck of any animal ever


    With their long necks and formidable bodies, sauropod dinosaurs have captured people’s imagination since the first relatively complete fossils were discovered in the United States in the late 1800s. The original specimen that the Natural History Museum’s Dippy was cast from was among these discoveries.

    Now an international team led by Stony Brook University palaeontologist Dr Andrew J. Moore, and including Prof. Paul Barret, Merit Researcher, from the London’s Natural History Museum, has reported that a Late Jurassic Chinese sauropod known as Mamenchisaurus sinocanadorum sported a 15-metre-long neck.

    The revelation comes as part of a paper that aims to document the diversity and evolutionary history of the family Mamenchisauridae, a group of particularly long-necked sauropod dinosaurs that roamed East Asia and possibly other parts of the world from the Middle Jurassic to the Early Cretaceous (approximately 174–114 million years ago).

    Mamenchisaurus sinocanadorum was discovered in approximately 162-million-year-old rocks from the Xinjiang Uyghur Autonomous Region of northwest China in 1987 by the China–Canada Dinosaur Project team, for which it was named in 1993. At approximately 15.1 meters, its neck was more than six times longer than the necks of giraffes and 1.5 times the length of a double-decker bus! This potentially makes it the longest neck of any animal to have ever existed.

    For sauropods, the long neck was one of the keys to achieving large body size. To power such a large body, sauropods had to be efficient at gathering food, and that's exactly what a long neck was built for. A sauropod could stand in one spot and graze the surrounding vegetation, conserving energy while taking in tons of food. Having a long neck probably also allowed sauropods to shed excess body heat by increasing their surface area, much like the ears of elephants. This lifestyle was exceptionally successful with the sauropod lineage appearing early in dinosaur evolutionary history and persisting until the final days of the Mesozoic, when an asteroid wiped out most of the dinosaurs, except for the relatives of modern birds.

    The question of which sauropod had the longest neck is not a simple one to answer. The largest sauropods tend to be some of the most poorly known as it is very hard to completely bury such a large animal in sediment, the first stage required for fossilization. Poor preservation of these specimens and their closest relatives often makes estimates of their neck length speculative.

    Although Mamenchisaurus sinocanadorum is known only from a handful of bones from the neck and skull, the research team was able to reconstruct its evolutionary relationships and thus make comparisons to the unusually complete skeletons of its closest relatives. This allowed them to conclude that Mamenchisaurus sinocanadorum had a neck approximately 15.1 meters long, the longest of any known sauropod.

    Lead author Dr Andrew J. Moore, Stony Brook University palaeontologist, said, ‘All sauropods were big, but jaw-droppingly long necks didn’t evolve just once.

    ‘Mamenchisaurids are important because they pushed the limits on how long a neck can be and were the first lineage of sauropods to do so. With a 15-metre-long neck, it looks like Mamenchisaurus sinocanadorum might be a record-holder – at least until something longer is discovered.’

    The question of how sauropods managed to evolve such long necks and large bodies without collapsing under their own weight has puzzled scientists since their discovery. When studying Mamenchisaurus the team were able to use computed-tomography (CT) scanning to reveal that the vertebrae were lightweight and hollow with air spaces comprising about 69–77% of their volume, similar to the lightly built skeletons of birds. However, such featherweight skeletons would also be more prone to injury. To combat this Mamenchisaurus had 4-metre-long rod-like neck ribs, bony extensions of the vertebrae that created overlapping bundles of rods on either side of the neck. These bundles would have stiffened the neck of Mamenchisaurus sinocanadorum, increasing its stability.

    The remaining mystery of Mamenchisaurus and many other long necked sauropods is understanding just how they drew air down these long necks all the way to their lungs.

    Prof. Paul Barrett, Merit Researcher, Natural History Museum London explains, ‘Like all other sauropod dinosaurs, Mamenchisaurus had a complex breathing apparatus that included not only the lungs, but also numerous balloon-like air sacs. These were connected to the lungs and windpipe but spread throughout the interior of the animal’s neck, chest and abdomen.

    ‘Taken in combination, these air sacs had a much greater volume than the lungs, and they even went inside the bones, hollowing them out. This extra space would have helped these gigantic sauropods to move the large volume of air in the lengthy windpipe that would have occupied their extraordinary necks’.

    While Mamenchisaurus sinocanadorum is now thought to have the longest neck of any dinosaur it was still not the biggest dinosaur. That title is held by a species in the titanosaur group and dinosaur fans will get the chance to see the colossal titanosaur Patagotitan mayorum, one of the largest known creatures to have ever walked our planet, this summer at London’s Natural History Museum.


    Source

    © Copyright Original Source



    The full paper describing the find is Re-assessment of the Late Jurassic eusauropod Mamenchisaurus sinocanadorum Russell and Zheng, 1993, and the evolution of exceptionally long necks in mamenchisaurids with the Abstract made available below:

    Abstract

    The sauropod genus Mamenchisaurus, from the Late Jurassic–Early Cretaceous of East Asia, has a convoluted taxonomic history. Although included in the first cladistic analysis of sauropods, only recently has the monophyly of Mamenchisaurus, and the anatomical diversity of the many penecontemporaneous East Asian eusauropods, been evaluated critically. Here, we re-describe the holotype and only specimen of M. sinocanadorum. Although the original diagnosis is no longer adequate, we identify several autapomorphies that support the validity of this species, including an elongate external mandibular fenestra and distinctive pneumatic structures on the cervical centra. We incorporate new data into a phylogenetic character matrix that also includes Bellusaurus and Daanosaurus, both of which are known only from juvenile material and are often hypothesized to be neosauropods (or close relatives thereof). We recover all species of Mamenchisaurus as part of a radiation of predominantly Middle–Late Jurassic East Asian eusauropods, but the genus is non-monophyletic, underscoring the need for further systematic revision of mamenchisaurid taxonomy. Analyses that score ontogenetically variable characters ambiguously recover Bellusaurus and Daanosaurus as juvenile mamenchisaurids, a hypothesis supported by several features that are unique to mamenchisaurids or exhibit little homoplasy, including anteriorly bifurcate cervical ribs. Finally, computed-tomography reveals extensive vertebral pneumaticity in M. sinocanadorum that is comparable to that of the largest sauropods, and updated scaling analyses imply a neck over 14 m long, rivalling estimates for other exceptionally long-necked sauropods. Previous work has suggested that the elongated cervical ribs of particularly long-necked sauropods such as M. sinocanadorum stabilized the neck by limiting its mobility. Given that extent of pneumaticity responds dynamically to a bone’s habitual loading, we propose that long cervical ribs – and other structural modifications that limited flexibility – promoted the evolution of increasingly long necks by producing a more predictable biomechanical milieu amenable to increased pneumatization.






    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

  • #2
    The article is sadly lacking in interesting images, so here is one of another type of Mamenchisaurus in a Japanese museum just to give you some idea of the length of the necks in this genus.

    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


    • #3
      Good heavens, SUCH a neck! However could the creature hold it up? Interesting.
      Watch your links! http://www.theologyweb.com/campus/fa...corumetiquette

      Comment


      • #4
        Originally posted by DesertBerean View Post
        Good heavens, SUCH a neck! However could the creature hold it up? Interesting.
        I wonder if some of them, much like modern giraffes, compete for mates by "necking."

        No. Not kissing. But rather swinging their necks and heads like giant clubs.

        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


        • #5
          Originally posted by rogue06 View Post
          I wonder if some of them, much like modern giraffes, compete for mates by "necking."

          No. Not kissing. But rather swinging their necks and heads like giant clubs.
          I only found out that happened relatively recently, and I remain disturbed by the violence. Especially if you get videos with sound.
          "Any sufficiently advanced stupidity is indistinguishable from trolling."

          Comment


          • #6
            Originally posted by rogue06 View Post
            The article is sadly lacking in interesting images, so here is one of another type of Mamenchisaurus in a Japanese museum just to give you some idea of the length of the necks in this genus.
            Uh, my first reaction to that reconstruction is that someone was drunk putting it together. Unless that creature had a tail of equal length to its neck, it just doesn't look functional. And even then, it looks like it often fell on its face when grazing too low.

            Comment


            • #7
              Originally posted by TheLurch View Post
              I only found out that happened relatively recently, and I remain disturbed by the violence. Especially if you get videos with sound.
              FWIU, they try to direct their strikes through those hard knobs on the top of their heads, the ossicones.

              That much mass[1] moved at the speed seen in that first gif concentrates the force of impact onto a small area much like a Medieval mace or morning star mean if a solid straight on hit is delivered that could result in serious damage.



              1. Given that it's males engaging in this sort of combative mating displays, you're looking at an animal weighing upwards around 4200 lbs. (1905 kg.).

              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

              Related Threads

              Collapse

              Topics Statistics Last Post
              Started by Hypatia_Alexandria, 03-18-2024, 12:15 PM
              48 responses
              135 views
              0 likes
              Last Post Sparko
              by Sparko
               
              Started by Sparko, 03-07-2024, 08:52 AM
              16 responses
              74 views
              0 likes
              Last Post shunyadragon  
              Started by rogue06, 02-28-2024, 11:06 AM
              6 responses
              48 views
              0 likes
              Last Post shunyadragon  
              Working...
              X