For the first time, dinosaur brain tissue was discovered in a dino fossil! Scientists have recently written findings of their research of a cast of a dinosaur’s brain cavity. The cast was found in 2004 by an amateur fossil collector. In an article for The Guardian on Thursday, October 27, Nicola Davis wrote, “Thought to belong to a relative of the Iguanodon, the thin layer of mineralised matter is the first fossilised brain tissue found for any land-living vertebrate.” Scientists believe the brain tissue is 130 million years old.
The cast measures at approximately 10 cm by 5 cm and is thought to be about a third of the size of an entire brain cavity. Scientists were able to use x-ray techniques to create a virtual, 3D model of the fossil, which has helped them explore its structure and how it was formed.
Another research technique provided even more insight. Davis wrote, “An approach known as scanning tunnelling microscopy shed light on the structure of the thin layers of mineralised tissue.” Alex Liu, co-author of the research from the University of Cambridge, said that scientists found fine detailed bundles of what is apparently collagenous fibres. These bundles are also interspersed with what appears to be capillaries. Both the collagenous fibres and the capillaries are what scientists would have expected to find on the outer protective tissue of the brain.
This exciting find debunks previously held conclusions that the some dinosaurs, including Iguanodons, had brains surrounded by a thick membrane, with the brain taking up about half of the brain cavity. However, Davis wrote that, “analysis of the fossilised tissues revealed only a thin, millimetre-thick layer of protective tissue, known as the meninges, covering tissue resembling that of the brain proper beneath.” The brain of the Iguanodon was apparently much larger than scientists thought. However, the size of the brain doesn’t reveal whether the Iguanodon had any greater intelligence, ability to communicate, etc.
This discovery also provides evidence that nueral tissues can be fossilised, which could prove previously held assumptions wrong. Typically scientists have thought that brains cannot fossilize because they decay rapidly after animals die.
Follow this link to read the coverage The Guardian published and to watch an animation of the cast and veneer of mineralised tissue.