An odd brown pebble, with a strange smooth surface and slightly crinkled in some parts, caught the eye of a fossil hunter on a beach back in 2004. The strange pebble proved to be the fossilized brain tissue of a dinosaur. 

The fossil hunter, named Jamie Hiscocks, found the preserved gray matter on the sands of a beach near Bexhill-on-Sea in England.

"I have always believed I had something special," Mr. Hiscocks said in an interview. "I noticed there was something odd about the preservation, and soft tissue preservation did go through my mind." 

Scientists at the Society for Vertebrate Paleontology meeting revealed that the strange pebble was an Endocast - known as an impression preserved inside a rock.

The brain must have come from a large prehistoric plant-eater known as the Iguanodon, a dinosaur from 133 million years ago. The dinosaur is believed to have died beside the water with its head resting on sedimentary grounds, which would have allowed the brain to be preserved in time.

The brain was observed to be sharing the same structure with brains of modern day animals such as birds and crocodiles, descendants of the Iguanodon.

"The chances of preserving brain tissue are incredibly small, so the discovery of this specimen is astonishing." said Dr. Alex Liu of Cambridge University's Department of Earth Sciences.

Jamie Hiscocks first revealed his discovery to the late Oxford University professor Martin Brasier, who was one of the world's leading palaeobiologists before his death in a road accident two years ago. It has now been highlighted in a special publication of the Geological Society of London published in tribute to Brasier.

As for the Endocast, researchers are in high hopes of finding more samples.

"Hopefully, this is the first of many such discoveries." Dr. David Norman of Cambridge University, who was a colleague of the late Martin Brasier, stated.