May 6, 2024

Marine Monsters of the Jurassic Seas Were Twice the Size of Killer Whales

An artists impression of the pliosaur. University of Portsmouth paleontologists have actually discovered proof recommending that pliosaurs, closely related to the Liopleurodon, might have reached up to 14.4 meters in length, two times the size of a killer whale. Credit: Megan Jacobs, University of Portsmouth
The vertebrae are clearly recognizable as being closely associated to a Pliosaurus species or comparable animal. Pliosaurs were like plesiosaurs, however with a larger elongated head, comparable to a crocodile, and a shorter neck.

An artists impression of the pliosaur. University of Portsmouth paleontologists have found evidence suggesting that pliosaurs, carefully associated to the Liopleurodon, could have risen to 14.4 meters in length, two times the size of a killer whale. Credit: Megan Jacobs, University of Portsmouth
Paleontologists have discovered proof that pliosaurs might have risen to 14.4 meters in length, two times the size of a killer whale, after discovering 4 big vertebrae in an Oxfordshire museum.
Over 20 years ago, the BBCs Walking with Dinosaurs television documentary series revealed a 25-meter-long Liopleurodon. This sparked heated disputes over the size of this pliosaur as it was believed to have actually been wildly overstated and most likely to have just reached an adult size of simply over 6 meters long.
The speculation was set to continue, now an opportunity discovery in an Oxfordshire museum has actually led to University of Portsmouth paleontologists releasing a paper on a comparable types possibly reaching a whopping 14.4 meters– two times the size of a killer whale.

Professor David Martill from the University of Portsmouths School of the Environment, Geography and Geosciences, stated: “I was an expert for the BBCs pilot program Cruel Sea and I hold my hands up– I got the size of Liopleurodon horrendously wrong. I based my calculations on some fragmentary material that suggested a Liopleurodon might grow to a length of 25 meters, however the proof was scant and it caused a great deal of debate at the time.
Digital three-dimensional scan images of pliosaur cervical vertebral centrum. Credit: University of Portsmouth
” The size price quote on the BBC back in 1999 was exaggerated, now we have some evidence that is a lot more trusted after a serendipitous discovery of 4 massive vertebrae.”
Professor Martills co-author, Megan Jacobs, was photographing an ichthyosaur skeleton at Abingdon County Hall Museum, while Dave browsed drawers of fossils. He was and found a big vertebra delighted to find the manager had 3 more of them in storage.
The vertebrae are plainly identifiable as being closely related to a Pliosaurus types or similar animal. Pliosaurs were like plesiosaurs, but with a larger extended head, comparable to a crocodile, and a shorter neck. They had 4 flippers, which acted as powerful paddles to propel them through water, and a relatively short tail.
Diagram placing the Abingdon pliosaur in a charm contest with a variety of current marine and semi-aquatic vertebrates to reveal the general body sizes. Credit: University of Portsmouth
After performing topographic scans, Professor Martill and associates determined this Late Jurassic marine reptile could have grown to in between 9.8 and 14.4 meters long.
He said: “We know these pliosaurs were extremely terrifying animals swimming in the seas that covered Oxfordshire 145-152 million years ago. They had massive skulls with big protruding teeth like daggers– as big, if not bigger than a T. rex, and certainly more effective.
” They had an enormous skull with substantial protruding teeth like daggers– as big, if not larger than a T. rex, and definitely more effective.”
— Professor David Martill, Professor of Palaeobiology
” They were at the top of the marine food chain and probably victimized ichthyosaurs, long-necked plesiosaurs and possibly even smaller marine crocodiles, merely by biting them in half and taking chunks off them. We understand they were massacring smaller sized marine reptiles since you can see bite marks in ichthyosaur bones in examples on screen in The Etches Collection in Dorset.”
The vertebrae were originally discovered during temporary excavations at Warren Farm in the River Thames Valley in Oxfordshire and originate from the Kimmeridge Clay Formation. This deposit is Late Jurassic in age, around 152 million years of ages.
Map of the area around Abingdon revealing the location (starred) of the discovery website of the 4 pliosaur cervical vertebrae. Credit: University of Portsmouth
Professor Martill added: “Its wonderful to show there was indeed a truly enormous pliosaur species in the Late Jurassic seas. Not yet on a par with the claims made for Liopleurodon in the renowned BBC TV series Walking With Dinosaurs, it would not surprise me if one day we discover some clear proof that this monstrous species was even larger.”
The paper is released in The Proceedings of the Geologists Association.
Recommendation: “A really gigantic pliosaur (Reptilia, Sauropterygia) from the Kimmeridge Clay Formation (Upper Jurassic, Kimmeridgian) of England” by David M. Martill and Megan L. Jacobs, Roy E. Smith, 10 May 2023, Proceedings of the Geologists Association.DOI: 10.1016/ j.pgeola.2023.04.005.