A brown pebble discovered on an English beach more a decade ago is actually the world's first known example of a fossilized dinosaur brain, scientists have confirmed.
The remarkable find is thought to have come from a large plant-eater such as the Iguanodon, which walked the earth about 133 million years ago.
It is believed the creature must have died near water with its head buried in sediment in a swamp or boggy ground, allowing its brain to be "pickled" and preserved.
Dr Alex Liu, from Cambridge University's Department of Earth Sciences, said: "The chances of preserving brain tissue are incredibly small, so the discovery of this specimen is astonishing."
Analysis of the fossil has revealed similarities with the brains of birds and crocodiles - both close relatives of dinosaurs - living today.