Peculiarities of the Structure and Locomotor Function of the Tail in Sauropterygia

@article{Sennikov2019PeculiaritiesOT,
  title={Peculiarities of the Structure and Locomotor Function of the Tail in Sauropterygia},
  author={Andrey G. Sennikov},
  journal={Biology Bulletin},
  year={2019},
  volume={46},
  pages={751 - 762}
}
Among ancient and modern marine reptiles, several structural types of the locomotor apparatus were or are present, supporting different styles of swimming. Ichthyosaurs, mosasaurs, saltwater crocodiles, and representatives of many other groups swam or swim with horizontal undulations of the body primarily using the tail with a vertical caudal fin. Sea turtles with a reduced tail and their body completely immobilized by the shell use only limbs transformed into flippers for swimming… 

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References

SHOWING 1-10 OF 82 REFERENCES
Taphonomic evidence for high-speed adapted fins in thunniform ichthyosaurs
TLDR
It is the first mechanostructural study of the control surfaces of a Jurassic ichthyosaur that adds essential evidence in support of the view that these forms were high-speed thunniform swimmers.
Soft tissue preservation in a fossil marine lizard with a bilobed tail fin.
TLDR
This fossil is reported from the Maastrichtian of Harrana in central Jordan, which preserves soft tissues, including high fidelity outlines of a caudal fluke and flippers, which provides the first indisputable evidence that derived mosasaurs were propelled by hypocercal tail fins.
Locomotor evolution in the earliest cetaceans: functional model, modern analogues, and paleontological evidence
TLDR
It is concluded that Ambulocetus may have locomoted by a combination of pelvic paddling and dorsoventral undulations of the tail, and that its locomotor mode in water resembled that of the modern otter Lutra most closely.
SWIMMING STYLES IN JURASSIC ICHTHYOSAURS
TLDR
Osteological predictors of postcranial flexibility in living aquatic axial locomotors are reviewed and used to identify the existence of a range of swimming styles within this generalized pattern among surveyed ichthyosaurs.
Evolution of Fish-Shaped Reptiles (reptilia: Ichthyopterygia) in Their Physical Environments and Constraints
TLDR
Ichthyosaurs were a group of Mesozoic marine reptiles that evolved fish-shaped body outlines that allowed estimation of such characteristics as optimal cruising speed, visual sensitivity, and even possible basal metabolic rate ranges.
EVIDENCES FOR A SEMI AQUATIC LIFE STYLE IN THE TRIASSIC DIAPSID REPTILE TANYSTROPHEUS
The paleoecology of the bizarre, long-necked tanystropheid diapsid Tanystropheus from the Middle and Late Triassic of Western and Eastern Tethys has been debated since the first discoveries. In the
MORPHOLOGY OF THE CAUDAL VERTEBRAE IN RHOMALEOSAURUS ZETLANDICUS AND A REVIEW OF THE EVIDENCE FOR A TAIL FIN IN PLESIOSAURIA
TLDR
The osteology of the tail is described and two morphological characteristics are interpreted as evidence for a caudal fin in Rhomaleosaurus, which corroborates evidence from other plesiosaurian taxa and suggests that a caUDal fin may have been widespread among plesioaurians, with implications for locomotion and behavior.
Convergent Evolution in Aquatic Tetrapods: Insights from an Exceptional Fossil Mosasaur
TLDR
This study demonstrates that a streamlined body plan and crescent-shaped caudal fin were already well established in Platecarpus, a taxon that preceded Plotosaurus by 20 million years, and expands the understanding of convergent evolution among marine reptiles, and provides insights into their evolution's tempo and mode.
A fishy mosasaur: the axial skeleton of Plotosaurus (Reptilia, Squamata) reassessed
TLDR
Analysis of vertebral centrum morphometrics and process orientation has revealed that a subsequent clade of secondarily aquatic reptiles, the mosasaurs, had developed a deep, fusiform body and a probable pursuit-predatory behaviour by the time of their sudden extinction at the Cretaceous-Paleogene boundary.
The Nothosaur Pachypleurosaurus and the Origin of Plesiosaurs
TLDR
It is concluded that the transition between primitive terrestrial diapsids and plesiosaurs occurred via a succession of changes in patterns of aquatic locomotion and Pachypleurosaurus has the greatest degree of development of the anterior portion of the shoulder girdle, suggesting that the recovery stroke was of considerable importance.
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