Caught in the act? Distraction sinking in ammonoid cephalopods

@article{Mapes2018CaughtIT,
  title={Caught in the act? Distraction sinking in ammonoid cephalopods},
  author={Royal H. Mapes and Neil H. Landman and Christian Klug},
  journal={Swiss Journal of Palaeontology},
  year={2018},
  volume={138},
  pages={141-149}
}
Two specimens of the Late Mississippian ammonoid cephalopod Metadimorphoceras sp. were recovered from the Bear Gulch Limestone in Montana. This unit was deposited in the lowest part of the Big Snowy Basin, where the bottom waters are thought to have been strongly oxygen deficient. The two nearly equally sized specimens are impressions with soft tissues preserved as brown carbonaceous smears. Diagenetic processes destroyed their aragonitic shells. The preserved soft tissues are interpreted as… 

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