A research group consisting of Professor Shoji Hayashi of the Faculty of Biogeography, Okayama University of Science, Researcher Yasutoshi Nakajima of the Atmosphere and Ocean Research Institute of the University of Tokyo, and Professor Martin Thunder of the University of Bonn in Germany I discovered the oldest fossil of "" and named it as a new genus and new species.
The extinct "Plesiosauria" are sea reptiles that flourished in the Mesozoic era, and many species have long necks, so they are called "Plesiosauria".It has four wing-shaped fins and is thought to have swam like flapping wings.From the Jurassic (4-2.01 million years ago) to the Cretaceous (1.45 million-1.45 million years ago), they reigned at the top of the marine food web.
Until now, Plesiosauria was thought to have appeared in the Jurassic period after the mass extinction event that occurred at the end of the Triassic period (about 2.52 million years ago to about 2.01 million years ago). Discovered a new skeletal fossil of marine reptiles from the last Triassic strata exposed at the Bonnenburg quarry in Germany, and due to its morphological characteristics, this fossil specimen is a genuine, oldest Plesiosauria. I concluded that.This discovery reveals that the Plesiosauria, which prospered after the Jurassic, already existed at the end of the Triassic and survived the extinction boundary.
It is unclear why Plesiosauria survived the extinction boundary, but one or both of the ecological characteristics of swimming in the open ocean and the physiological characteristics of short-term growth are important factors. It is possible that this was the case.
Paper information:[Science Advances] A Triassic plesiosaurian skeleton and bone histology inform on evolution of a unique body plan