Jaw-Dropping Discovery: World’s Oldest ‘Stomach Stone’ Fossil Unearthed on the Jurassic Coast Rewrites Prehistoric Dietary History

The oldest fossil “stomach stone” has been discovered at Kimmeridge Bay, Dorset on the famous “Jurassic Coast”. The baseball-sized fossil was found by the eminent palaeontologist Dr Steve Etches MBE. It is thought to be around 150 million years old. The fossil is at least 59 million years older than the previous oldest known fossilised stomach stone.

The world’s oldest fossil “stomach stone” also known as a calculus. This exceptionally rare fossil was found at Kimmeridge Bay. It is estimated to be approximately 150 million years old (Late Jurassic). Picture credit: Ivan Sansom.

The fossil record's oldest known calculus (an enterolith of the gastrointestinal tract), from the Kimmeridge Clay Formation (Upper Jurassic), UK - ScienceDirect

Dr Etches sought the opinions of other palaeontologists to see if he could learn more about this mystery object. It was initially dismissed as not being organic in nature. The consensus was that it had formed through geological processes.

The fossil record's oldest known calculus (an enterolith of the gastrointestinal tract), from the Kimmeridge Clay Formation (Upper Jurassic), UK - ScienceDirect

The stone was passed on to experienced fossil preparator Nigel Larkin who compared it to material in the collections of the Royal College of Surgeons, England, and the University College London (UCL) pathology collections.

It soon became clear the stone was a “calculus”. A “calculus” is a concretion, a collection of minerals that form in the body. These objects are found in many parts of the body, the kidneys, the bladder, the stomach the urinary tract and they have a very specific internal structure.

Dr Steve Etches MBE holding the world’s oldest calculus. One of the UK’s rarest fossils. Found by Steve at Kimmeridge on the Jurassic Coast. Picture credit: The Etches Collection.

An Exceptional Fossil Discovery

Only a handful of calculi have been discovered in the fossil record. It is thought that more exist, but they have not been formally identified.

Nigel Larkin commented:

“I was fascinated by this very curious mystery object and was determined to discover what it was. Unless stomach stones are actually found preserved within a skeleton it is almost impossible to tell what sort of animal it might have formed inside.”

Pliosaur sea monster fossil will feature on BBC documentary

The size of the stomach stone and the location of its discovery (marine deposits) suggests that this object formed inside the body of a large marine reptile. The calculus could have come from a plesiosaur, an ichthyosaur, a pliosaur or perhaps a marine crocodile.

Spend a weekend exploring the Jurassic Coast with top experts - Wales Online

Dr Ivan Sansom, Senior Lecturer in Palaeobiology at the University of Birmingham, carried out microscopic analyses of the stone to determine the exact structure of the specimen and its mineral composition. Based on this analysis Dr Sansom concluded that this stone had formed in the gastro-intestinal tract. It was a fossil “stomach stone”.

The fossil “stomach stone” is estimated to be around 150 million years old (Late Jurassic). This discovery extends the range of known calculi in the fossil record by approximately 59 million years. It is the only fossil of its kind to have been found in the UK. It also confirms their occurrence in marine palaeoenvironments rather than just terrestrial deposits.

Why the Jurassic Coast Is One of the Best Fossil-Collecting Sites on Earth | Travel | Smithsonian Magazine

Everything Dinosaur acknowledges the assistance of a media release from the University of Reading in the compilation of this article.

The scientific paper: “The fossil record’s oldest known calculus (an enterolith of the gastrointestinal tract), from the Kimmeridge Clay Formation (Upper Jurassic), UK” by Nigel R. Larkin, Thomas Henton, Steve Etches, Adrian J. Wright, Tzu-Yu Chen, Laura L. Driscoll, Richard M. Shelton and Ivan J. Sansom published in the Proceedings of the Geologists’ Association.

Sia

Related Posts

Lost Titan Resurrected: Brazil’s Largest Dinosaur Emerges from 60-Year Hiatus, Rewriting History in Unbelievable Cupboard Discovery

Brazil’s largest ever dinosaur is found: Fossils discovered in a cupboard after 60 years shed light on 82ft-long beast] A South American dinosaur of truly magnificent proportions…

Lost Titan Resurrected: Brazil’s Largest Dinosaur Emerges from 60-Year Hiatus in Unbelievable Cupboard Discovery, Rewriting History

Brazil’s largest ever dinosaur is found: Fossils discovered in a cupboard after 60 years shed light on 82ft-long beast] A South American dinosaur of truly magnificent proportions…

Unearthing Jurassic Wonders: Delving into Eype Starfish Bed on the Jurassic Coast for Incredible Fossil Discoveries

Between Seatown and Eype, on the West Dorset coast (part of the Dorset and East Devon Coast World Heritage Site), there is a remarkable layer of rock…

Unearthing Ancient Wonders: Exploring Jurassic Coast’s Eype Starfish Bed for Spectacular Prehistoric Fossil Finds

Between Seatown and Eype, on the West Dorset coast (part of the Dorset and East Devon Coast World Heritage Site), there is a remarkable layer of rock…

Thailand’s Treasures: Remarkable Neornithischian Dinosaur Fossil Revealed in Astonishing Prehistoric Discovery

Minimocursor phunoiensis is the earliest known neornithischian dinosaur from Southeast Asia as well as one of the best-preserved dinosaurs ever found in the region. Reconstruction of Minimocursor…

Thailand’s Prehistoric Surprise Unveiled – Newly Discovered Neornithischian Dinosaur Rewrites Evolutionary Tale

Minimocursor phunoiensis is the earliest known neornithischian dinosaur from Southeast Asia as well as one of the best-preserved dinosaurs ever found in the region. Reconstruction of Minimocursor…

Leave a Reply

Your email address will not be published. Required fields are marked *