An amateur collaborating with paleontologists from the University of Portsmouth has found the first fossilized side-necked turtle in Great Britain. These ancient remains represent the earliest known example of a side-necked panpleurodiran turtle, so named because they fold their necks into their shells when threatened. This means they can only see with one eye.

The turtle fossil, first found on National Trust Beach on the Isle of Wight, is a nearly complete shell with cervical, dorsal and caudal vertebrae, shoulder blades, pelvic girdle and appendicular bones. Unfortunately, there was no skull.

Lead author Megan Jacobs said: “This is an incredible discovery because this is the first time such a turtle has been found in the UK. Even more exciting, we used a new radiometric dating technique to determine the fossil’s age beyond doubt. On top of that, CT The scan revealed all the tiny bones inside. It’s truly incredible for what looks like rolled beach pebbles!

Lead author Megan Jacobs. Credit: Pete Johnston.

Megan and her colleagues extracted minerals from the turtle’s shell and analyzed them for uranium and lead. By measuring the ratio of lead to radioactive uranium, they determined that the tortoise came from the Lower Cretaceous, about 127 million years ago.

The fossil was first found by fossil collector Steve Burbridge on the shores of Brooke Bay, off the southwest coast of the Isle of Wight. This part of the coast is well known for fossil vertebrates from the cliffs and coastal ledges at the top of the Wessex Formation’s famous Isle of Wight Fossil Beds. This is the first time radiometric dating has been used for fossils from the Wessex Formation.

Megan added: “We named the turtle ‘Barbie’ after Steve, who donated the specimen to the Dinosaur Island Museum in Sandown on the Isle of Wight.”

The researchers also used state-of-the-art microcomputer scanning at the University of Portsmouth’s Center for Future Technologies to identify various small bones. This advanced imaging technique provided invaluable information about the structure and composition of the turtle without damaging its shell. Steve said: “I can’t even imagine publishing one of my findings. I would never have guessed that this is such an incredibly important fossil. It’s great to see all the little bones in it.”

Geologist Dr Catherine Mottram, from the University of Portsmouth School of Environment, Geography and Earth Sciences, is a co-author of the paper. “It’s very exciting that we can use advanced radiometric dating techniques for the first time to provide absolute constraints on this important sequence,” she said. Source