Morphology and Function of the Vertebral Column in Remingtonocetus domandaensis (Mammalia, Cetacea) from the Middle Eocene Domanda Formation of Pakistan

@article{Bebej2011MorphologyAF,
  title={Morphology and Function of the Vertebral Column in Remingtonocetus domandaensis (Mammalia, Cetacea) from the Middle Eocene Domanda Formation of Pakistan},
  author={Ryan M. Bebej and Munir ul-Haq and Iyad S. Zalmout and Philip D. Gingerich},
  journal={Journal of Mammalian Evolution},
  year={2011},
  volume={19},
  pages={77-104}
}
The archaeocete family Remingtonocetidae is a group of early cetaceans known from the Eocene of India and Pakistan. Previous studies of remingtonocetids focused primarily on cranial anatomy due to a paucity of well-preserved postcranial material. Here we describe the morphology of the known vertebral column in Remingtonocetus domandaensis based largely on a single well-preserved partial skeleton recovered from the upper Domanda Formation of Pakistan. The specimen preserves most of the precaudal… Expand
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References

SHOWING 1-10 OF 113 REFERENCES
Functional Morphology of the Vertebral Column in Remingtonocetus (Mammalia, Cetacea) and the Evolution of Aquatic Locomotion in Early Archaeocetes.
TLDR
It is suggested that the evolution of tail-powered swimming in early cetaceans was preceded by an increase in lumbar mobility, and the vertebral morphology of an early archaeocete (Remingtonocetus domandaensis) is documents and quantitative methods for assessing vertebral function in fossil forms are developed. Expand
Partial Skeletons of Indocetus Ramani (Mammalia, Cetacea) from the Lower Middle Eocene Domanda Shale in the Sulaiman Range of Punjab (Pakistan)
Indocetus ramani is an early middle Eocene archaeocete described by Sahni and Mishra from Kutch in western India. The type and only specimen known previously is a partial skull. New specimens fromExpand
Vertebral osteology in Delphinidae (Cetacea)
TLDR
Reconstruction of the historical sequence of anatomical innovations identifies syncliny as an early and critical step in delphinid column evolution and Trait distribution supports evolutionary isolation of Pseudorca and Orcinus from remaining Delphinids, inclusion of Feresa and Peponocephala amongdelphinine delph inids, and subdivision ofDelphinines on the basis of centrum dimensions, neural spine inclination and count. Expand
NEW GENUS OF DORUDONTINE ARCHAEOCETE (CETACEA) FROM THE MIDDLE‐TO‐LATE EOCENE OF SOUTH CAROLINA
TLDR
The pelves resemble those of Basilosaurus, documenting a similar stage of hind limb reduction in dorudontines and suggesting that Chrysocetus was not able to support its body on land. Expand
NEW ARCHAEOCETES (MAMMALIA, CETACEA) FROM THE MIDDLE EOCENE DOMANDA FORMATION OF THE SULAIMAN RANGE,
Three new archawcetes of late early Lutetian are described from the Domanda Formation of the Sulaiman Range in southwestern Punjab, Pakistan. Two are protocetids: Takracetus simus is distinctive inExpand
THE POSTCRANIAL SKELETON OF EARLY EOCENE PAKICETID CETACEANS
  • S. Madar
  • Biology
  • Journal of Paleontology
  • 2007
TLDR
When both postcranial morphology and microstructure are considered, it can be concluded that pakicetid cetaceans were highly adapted for an aquatic niche. Expand
Makaracetus Bidens, a New Protocetid Archaeocete (Mammalia, Cetacea) from the Early Middle Eocene of Balochistan (Pakistan)
Makaracetus bidens is a new genus and species of late Lutetian (early middle Eocene) archaeocete collected from the Kunvit area near Rakhni, in eastern Balochistan Province, Pakistan. M. bidens wasExpand
Form, Function, and Anatomy of Dorudon Atrox (Mammalia, Cetacea): An Archaeocete from the Middle to Late Eocene of Egypt
Dorudon atrox is a medium-sized archaeocete cetacean, around five meters in length from snout to tail in life, and is known from the Birket Qarun and Gehannam Formations of Fayum, Egypt. TheseExpand
Additional holotype remains of Ambulocetus natans (Cetacea, Ambulocetidae), and their implications for locomotion in early whales
TLDR
Contin excavation at the type locality of Ambulocetus natans led to the recovery of a majority of the axial skeleton of the holotype, including both innominates, the sacrum, and most of the thoracic cage and thoracolumbar vertebral column, suggesting that previous estimates of spinal length derived from models of mesonychid ancestry may be inaccurate. Expand
Implications of Vertebral Morphology for Locomotor Evolution in Early Cetacea
TLDR
Although almost invariably fragmentary, early cetacean postcranial skeletons are surprisingly informative, and can complement morphological indicators of diet, sensory specializations, and skull reorganization to fill in some of the gaps in the authors' understanding of the dramatic transition of earlyCetaceans as they moved from land to water. Expand
...
1
2
3
4
5
...