A "BROWN pebble" spotted by a fossil hunter has been confirmed as the first known example of petrified dinosaur brain with help from an Oxford scientist.

The specimen discovered in Sussex more than a decade ago is thought to have come from a large plant eater such as Iguanodon, which lived about 133 million years ago.

It was discovered by fossil hunter Jamie Hiscocks on a beach near Bexhill-on-Sea in 2004.

Scientists believe the dinosaur's head was buried in mud at the bottom of a swamp, allowing its brain to be "pickled" and preserved.

The find's importance was first recognised by Oxford University Professor Martin Brasier who co-led the research prior to his death in a road accident in 2014.

It is highlighted in a special publication of the Geological Society of London published in tribute to the professor, who was one of the world's leading palaeobiologists.

Mr Hiscocks, who is named as one of the study's authors, said: "I have always believed I had something special. I noticed there was something odd about the preservation, and soft tissue preservation did go through my mind.

"Martin realised its potential significance right at the beginning, but it wasn't until years later that its true significance came to be realised.

"In his initial email to me, Martin asked if I'd ever heard of dinosaur brain cells being preserved in the fossil record. I knew exactly what he was getting at. I was amazed to hear this coming from a world-renowned expert like him."