The first confirmed discovery of a fossilised dinosaur brain is an 133 million-year-old iguanodontian dinosaur brain, which was originally found in 2004, in Bexhill, East Sussex, UK, by Jamie Hiscocks (UK). At the time, no-one knew exactly what the fossil was, although Jamie believed he had something special on his hands. In 2016, scientists announced that the fossil, after being studied, was confirmed to be the first known example of fossilised dinosaur brain tissue. The dinosaur was a relative of the iguanodon and it lived in the early Cretaceous period. The group of scientists think that its brain was effectively 'pickled' - the dinosaur fell into an stagnant pond and sank to the bottom, and the acidic, low-oxygen conditions allowed for the brain to be preserved. Over the years the brain tissue was mineralised, which means that the soft organic matter has slowly been replaced with mineral, forming a hard cast of the brain that allows us to see the brain's structure. The fossil shows that this dinosaur's brain had many features in common with the brains of modern birds and reptiles. Photo credit: David Wacey