• Corpus ID: 195258934

12 Speculations on Buoyancy Control and Ecology in some Heteromorph Ammonites

@inproceedings{Klinger201212SO,
  title={12 Speculations on Buoyancy Control and Ecology in some Heteromorph Ammonites},
  author={Herbert Christian Klinger},
  year={2012}
}
Possible buoyancy control in some heteromorph ammonite groups is investigated in terms of the position of the siphuncle. Groups investigated include some torticones, ancylocones and orthocones. In Turrilitinae the •idapical position of the siphuncle causes rapid decoupling and may possibly permit the shell to retain significant amounts of cameral liquid, which may be lavourable to a vagile benthonic mode of life. Ancylocones have a very stable floating position in the adult stage, but lateral… 
Speculations on the ethology of some heteromorph ammonites
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The mode of life of the turricones and colchicones are considered against the background of functional–morphological analyses of their shell modifications during ontogeny and transformation from helical to planispiral coiling indicates a transition to a more active, free-swimming mode oflife.
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The biomechanics of uncoiled heteromorph ammonoids with body chambers that terminate in U-shaped hooks (ancylocones) were investigated with virtual and physical models of Audouliceras renauxianum to suggest that stability, orientation and directional efficiency are key selective pressures for some heteromorph shells, which may have primarily served as hydrostatic devices.
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Understanding the hydrostatic properties of ectocochleate cephalopods is essential to study the functional morphology of their shells. The conditions for neutral buoyancy, static orientation of the
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A New Species of Yezoceras (Ammonoidea, Nostoceratidae) from the Coniacian in the Northwestern Pacific Realm
Abstract. A nostoceratid ammonoid Yezoceras elegans sp. nov. is newly described from the Coniacian of the Haboro area in Hokkaido, northern Japan. Yezoceras elegans sp. nov. having loosely coiled
A new approach using high-resolution computed tomography to test the buoyant properties of chambered cephalopod shells
TLDR
A technique using high-resolution computed tomography to quantify the buoyant properties of chambered shells without reducing the shell to ideal spirals or eliminating inherent biological variability is developed, which challenges past inferences of benthic life habits based solely on calculations of negative buoyancy.
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