Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "conch" wg kryterium: Temat

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-3 z 3
    Tytuł:
    The origin of ammonoid locomotion
    Autorzy:
    Klug, C
    Korn, D.
    Powiązania:
    https://bibliotekanauki.pl/articles/21156.pdf
    Data publikacji:
    2004
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    phylogenesis
    Bactritida
    ontogenesis
    Ammonoidea
    conch
    coiling
    Devonian
    paleontology
    locomotion
    ammonoid
    Opis:
    Evolution of the coiled ammonoid conch from the uncoiled bactritid conch was probably coupled with changes in manoeuvrability and swimming velocity. The gradual transformation of uncoiled to coiled ammonoid conchs has essential functional consequences. The radical change in conch geometry during phylogeny but also in ontogeny of early ammonoids implies a shift of the aperture from an original roughly downward, via a downward oblique and an upward oblique to an upward orientation, presuming a neutrally buoyant condition of the ammonoid animal. Similar trends were reconstructed for the three main ammonoid lineages in the Middle Devonian, the agoniatitid, the anarcestid, and the tornoceratid lineages. This allowed an increase in manoeuvrability and in the maximum horizontal swimming speed.
    Źródło:
    Acta Palaeontologica Polonica; 2004, 49, 2
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Virtual 3D modeling of the ammonoid conch to study its hydrostatic properties
    Autorzy:
    Moron-Alfonso, D.A.
    Peterman, D.J.
    Cichowolski, M.
    Hoffmann, R.
    Lemanis, R.E.
    Powiązania:
    https://bibliotekanauki.pl/articles/2082232.pdf
    Data publikacji:
    2020
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    Cephalopoda
    Ammonoidea
    virtual modeling
    3D
    conch
    CT-scan
    morphometry
    Cretaceous
    Antarctica
    Opis:
    Computed tomography has provided a wealth of biological data that now stands beside a vast, more traditional, morphometric database. By exploiting these two resources, we present a novel methodology to construct intricate, virtual cephalopod shells. As a case of study, we applied this method to Maorites seymourianus using data obtained from a previous work. For this purpose, evaluation of the conch geometry, and the definition of new parameters such as the segment width expansion rate (SWER), segment height expansion rate (SHER), the segment thickness expansion rate (STER), and three indices related, were introduced. The conch geometry of M. seymourianus follows a spiral that can be defined by a polynomial function. While similar to a logarithmic function, a polynomial fit is preferred because it reveals higher values of whorl expansion at the early ontogenetic phase and lower values reaching the adult body chamber. Results on the hydrostatic properties of the virtual models indicate that M. seymourianus would have a near neutral buoyancy, ranging from slightly positive to slightly negative, depending upon parameters that influence organismal mass. Positions of the center of mass and the center of buoyancy indicate that the studied species would have a relatively low hydrostatic stability, estimating a shell orientation of approximately 74–76° with respect to the vertical, with the aperture slightly inclined downwards relative to the horizontal plain.
    Źródło:
    Acta Palaeontologica Polonica; 2020, 65, 3; 467-480
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Soft-tissue attachment structures and taphonomy of the Middle Triassic nautiloid Germanonautilus
    Autorzy:
    Klug, C
    Lehmkuhl, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/21103.pdf
    Data publikacji:
    2004
    Wydawca:
    Polska Akademia Nauk. Instytut Paleobiologii PAN
    Tematy:
    soft tissue attachment
    Nautiloidea
    nautiloid
    Triassic
    structure
    conch
    taphonomy
    Germany
    Middle Triassic
    paleoecology
    Germanonautilus
    paleontology
    Opis:
    New examinations of numerous steinkerns of the Middle Triassic nautiloid Germanonautilusfrom southern Germany revealed new anatomic, ecologic, and taphonomic details, which are compared with Recent Nautilus. The attachment structures of the cephalic retractor muscle (large scar) and of the dorsal (black layer) and the posterior mantle (posterior narrow scar, anterior band scar of the mantle and septal myoadhesive bands), some with tracking bands (recording the anteriorward movement of the soft body during ontogeny), were seen in several specimens. The shape and proportions of these soft−tissue attachment structures resemble those of Recent Nautilus macromphalus and indicate a similar soft part anatomy. Based on their conch geometry, the mode of locomotion of Germanonautilus is reconstructed. Owing to the wide whorl cross section and the high whorl expansion rate, drag of the conchs was high, the aperture was oriented at an oblique angle which made Germanonautilus a rather slow horizontal swimmer. Because of their large sizes and widths, conchs of Germanonautilus were often deposited on their broad venters, forming elevated “benthic islands” (secondary hardgrounds). A broad range of animals (fish, decapods, ophiurans, crinoids, brachiopods, bryozoans, bivalves, Spirorbis, foraminiferans) lived in and on these comparatively large secondary hardgrounds.
    Źródło:
    Acta Palaeontologica Polonica; 2004, 49, 2
    0567-7920
    Pojawia się w:
    Acta Palaeontologica Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-3 z 3

      Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies