After finding four large vertebrae in an Oxfordshire museum, paleontologists have discovered evidence that pliosaurs may have grown to 14.4 meters in length, twice the length of a killer whale. Over 20 years ago, the BBC showed in the television documentary series “Walking with Dinosaurs”: Liopleurodon is 25 meters long. This has sparked heated debate about the size of this pliosaur, as it is thought to have been greatly exaggerated and likely to have reached an adult size of just over six metres.

Speculation would continue, but a find, now accidentally found in an Oxfordshire museum, has prompted paleontologists at the University of Portsmouth to publish a paper on a similar species, potentially reaching 14.4 meters – twice the size of a killer whale. Professor David Martill from the University of Portsmouth’s School of Environment, Geography and Geosciences said: “I was a consultant on the BBC’s ‘Cruel Sea’ pilot and I put my hands up in the air – I got the size of Liopleurodon horribly wrong. I based my calculations on some piecey material. liopleurodon It can grow up to 25 feet, but there was little evidence and it caused a lot of controversy at the time.

Digital 3D scan of the center of a Pliosaurus cervical vertebra. Credit: University of Portsmouth

“The size estimate by the BBC in 1999 was exaggerated, but now we have some evidence that is much more reliable after the accidental discovery of the four major vertebrae.”

Dave was rummaging through the fossil boxes while Professor Martill’s co-author Megan Jacobs was photographing an ichthyosaur skeleton at the Abingdon County Museum. She found a large vertebra, and she was delighted to learn that the curator had kept three more of them.

The vertebrae are clearly identified as closely related to the species. pliosaurus or a similar animal. Pliosaurs were similar to plesiosaurs, but had a larger, long, crocodile-like head and shorter necks. They had four fins and a relatively short tail that acted as powerful paddles to propel them through the water.

Diagram showing Abingdon Pliosaurus entering a “beauty contest” with a number of modern aquatic and semi-aquatic vertebrates to demonstrate its overall body size. Credit: University of Portsmouth Professor Martil and colleagues using topographic surveys estimate that this Late Jurassic marine reptile may have grown between 9.8 and 14.4 meters.

“We know that these pliosaurs were very scary animals that swam in the seas that covered Oxfordshire 145-152 million years ago. They had huge skulls with enormous fangs sticking out like daggers; T. rex And of course stronger.

“They had a huge skull with huge fangs protruding like daggers – as big as a T. Rex and definitely more powerful.”

— Professor David Martil, professor of paleobiology

“They were at the top of the marine food chain and probably preyed on ichthyosaurs, long-necked plesiosaurs, and perhaps even smaller marine crocodiles simply by splitting and dissecting them. We know they killed smaller marine reptiles because you can see bite marks on ichthyosaur bones in specimens from the Etches Collection in Dorset.”

The vertebrae were first discovered during a temporary excavation at Warren Farm in the Thames Valley in Oxfordshire and came from the Kimmeridge Clay Formation. The age of this deposit belongs to the late Jurassic period, which is about 152 million years.