• Axial skeleton of Tiktaalik roseae

    From Pandora@pandora@knoware.nl to sci.bio.paleontology on Thu Apr 4 15:32:02 2024
    From Newsgroup: sci.bio.paleontology

    The axial skeleton of Tiktaalik roseae

    Abstract

    The axial columns of the earliest limbed vertebrates show distinct
    patterns of regionalization as compared to early tetrapodomorphs.
    Included among their novel features are sacral ribs, which provide
    linkage between the vertebral column and pelvis, contributing to body
    support and propulsion by the hindlimb. Data on the axial skeletons of
    the closest relatives of limbed vertebrates are sparce, with key
    features of specimens potentially covered by matrix. Therefore, it is
    unclear in what sequence and under what functional context
    specializations in the axial skeletons of tetrapods arose. Here, we
    describe the axial skeleton of the elpistostegalian Tiktaalik roseae and
    show that transformations to the axial column for head mobility, body
    support, and pelvic fin buttressing evolved in finned vertebrates prior
    to the origin of limbs. No atlasrCoaxis complex is observed; however, an independent basioccipitalrCoexoccipital complex suggests increased
    mobility at the occipital vertebral junction. While the construction of vertebrae in Tiktaalik is similar to early tetrapodomorphs, its ribs
    possess a specialized sacral domain. Sacral ribs are expanded and
    ventrally curved, indicating likely attachment to the expanded iliac
    blade of the pelvis by ligamentous connection. Thus, the origin of novel
    rib types preceded major alterations to trunk vertebrae, and linkage
    between pelvic fins and axial column preceded the origin of limbs. These
    data reveal an unexpected combination of post-cranial skeletal
    characters, informing hypotheses of body posture and movement in the
    closest relatives of limbed vertebrates.

    Open access:
    https://www.pnas.org/doi/10.1073/pnas.2316106121
    --- Synchronet 3.21d-Linux NewsLink 1.2
  • From erik simpson@eastside.erik@gmail.com to sci.bio.paleontology on Thu Apr 4 07:01:47 2024
    From Newsgroup: sci.bio.paleontology

    On 4/4/24 6:32 AM, Pandora wrote:
    The axial skeleton of Tiktaalik roseae

    Abstract

    The axial columns of the earliest limbed vertebrates show distinct
    patterns of regionalization as compared to early tetrapodomorphs.
    Included among their novel features are sacral ribs, which provide
    linkage between the vertebral column and pelvis, contributing to body support and propulsion by the hindlimb. Data on the axial skeletons of
    the closest relatives of limbed vertebrates are sparce, with key
    features of specimens potentially covered by matrix. Therefore, it is unclear in what sequence and under what functional context
    specializations in the axial skeletons of tetrapods arose. Here, we
    describe the axial skeleton of the elpistostegalian Tiktaalik roseae and show that transformations to the axial column for head mobility, body support, and pelvic fin buttressing evolved in finned vertebrates prior
    to the origin of limbs. No atlasrCoaxis complex is observed; however, an independent basioccipitalrCoexoccipital complex suggests increased
    mobility at the occipital vertebral junction. While the construction of vertebrae in Tiktaalik is similar to early tetrapodomorphs, its ribs
    possess a specialized sacral domain. Sacral ribs are expanded and
    ventrally curved, indicating likely attachment to the expanded iliac
    blade of the pelvis by ligamentous connection. Thus, the origin of novel
    rib types preceded major alterations to trunk vertebrae, and linkage
    between pelvic fins and axial column preceded the origin of limbs. These data reveal an unexpected combination of post-cranial skeletal
    characters, informing hypotheses of body posture and movement in the
    closest relatives of limbed vertebrates.

    Open access:
    https://www.pnas.org/doi/10.1073/pnas.2316106121
    Good catch.
    --- Synchronet 3.21d-Linux NewsLink 1.2
  • From Popping Mad@rainbow@colition.gov to sci.bio.paleontology on Sat Apr 13 10:19:47 2024
    From Newsgroup: sci.bio.paleontology

    On 4/4/24 10:01, erik simpson wrote:
    Included among their novel features are sacral ribs,


    we owe it to them for barbeque spare ribs
    --- Synchronet 3.21d-Linux NewsLink 1.2
  • From erik simpson@eastside.erik@gmail.com to sci.bio.paleontology on Sat Apr 13 08:39:18 2024
    From Newsgroup: sci.bio.paleontology

    On 4/13/24 7:19 AM, Popping Mad wrote:
    On 4/4/24 10:01, erik simpson wrote:
    Included among their novel features are sacral ribs,


    we owe it to them for barbeque spare ribs

    I wonder; would it taste like fish or chicken?
    --- Synchronet 3.21d-Linux NewsLink 1.2
  • From jillery@69jpil69@gmail.com to sci.bio.paleontology on Mon Apr 15 15:39:30 2024
    From Newsgroup: sci.bio.paleontology

    On Sat, 13 Apr 2024 08:39:18 -0700, erik simpson
    <eastside.erik@gmail.com> wrote:
    On 4/13/24 7:19 AM, Popping Mad wrote:
    On 4/4/24 10:01, erik simpson wrote:
    Included among their novel features are sacral ribs,


    we owe it to them for barbeque spare ribs

    I wonder; would it taste like fish or chicken?
    Chicken of the Sea?
    --- Synchronet 3.21d-Linux NewsLink 1.2