SALT LAKE CITY — Dinosaur smarts may be a mystery. But their brains, at least, are now a bit more concrete.

That’s thanks to a chunk of fossilized brain tissue. It was discovered in a tidal pool in southern England. It is the first reported fossil brain tissue from a dinosaur ever identified, claim researchers in Britain. Roughly 133 million years old, this fossil preserves the brain’s wrinkled topology, or structure.

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David Norman works at the University of Cambridge. As a paleontologist, he studies fossilized plants and animals. Norman presented the fossil, here, on October 27. He was a speaker at the annual meeting of the Society of Vertebrate Paleontology. The meeting focuses on new discoveries or interpretations of fossilized animals that had a stiff nerve cord running down their backs, two eyes and a brain.

The fossil is roughly the size of a palm-sized rock. It includes bits of bone and the tough outer layers of the brain. A closer look with a microscope revealed the brain’s plumbing. Tiny, branching tubes — blood vessels — crisscross the fossil’s surface and enter what was once brain tissue.

This fossil brain had “pits and creases and folds,” Norman reports. “It’s a little bit like your bed when you wake up in the morning — somewhat crinkled and folded.”

A microscope image shows what appear to be blood vessels (arrows point to them) in this dino-brain fossil. D. Norman

A beachcombing fossil collector found the specimen in 2004. It probably belonged to a plant-eating dinosaur, such as Barilium or Hypselospinus. These guys had a body about the length of a Volkswagen Beetle.

Soft tissue is unusual in the fossil record. This dino probably fell head first into a boggy swamp. The water may have been acidic. That means there was some chemical in it that was releasing hydrogen ions, giving it a sour taste. There likely also was some salt present. So the water would have “literally pickled” the dinosaur’s brain, Norman said. Pickling prevents bacteria from getting at the tissue and breaking it down. Later, minerals would have fossilized the pickled tissue.

The resulting fossil offers no insight into “the mind of dinosaurs,” Norman notes. But it does provide “remarkable preservation” of a piece of the brain itself.

Details of the fossil are also described online October 27 in a special publication of the Geological Society of London.