The world’s oldest preserved brain found in a 319-million-year-old fish fossil

In general, fish are not known to be intelligent creatures with tremendous brain power. Many believe that Goldfish, in particular, have memory lapses of three seconds, but that is not true. The brain of another fish recently grabbed the spotlight for a different reason.

A 319-million-year-old fish fossil at Manchester Museum has revealed that inside its skull is a brain and cranial nerves that are the oldest well-preserved vertebrate brain ever discovered. This rare find has excited researchers around the world and is described in an article.

Discovered over 100 years ago in a mine in Lancashire, UK, the fossil was encased in soapstone. It has since sat in the museum, but was recently examined by researchers. Known as Coccocephalus wildi, it is the only specimen of this type found. Although only the skull was uncovered, the fish likely extended six to eight inches.

While they were not originally looking for a brain, the researchers discovered a foreign object in the skull using CT scans. Like vertebrate brains, the object was bilaterally symmetrical, contained hollow spaces, and had multiple filaments (like cranial nerves). The brain folds inward, unlike today’s ray-finned fish.

Vertebrate brains decay quickly, so finding fossilized specimens is unusual. The dead creature likely quickly became engulfed in sediments with low oxygen levels. The paper’s lead author, Sam Giles, from the University of Birmingham, said in a statement:

“This unexpected finding of a three-dimensionally preserved vertebrate brain gives us amazing insight into the neural anatomy of ray-finned fish. It tells us a more complicated pattern of brain evolution than suggested by living species alone, allowing us to better define how and when today’s bony fish evolved.”

“Comparisons with live fish showed that the brain of Coccocephalus is most similar to the brains of sturgeons and paddlefish, which are often called ‘primitive’ fish because they diverged from all other living ray-finned fish more than a year ago. than 300 million years.”

The 30,000 species of ray-finned fish in the modern world are half of all vertebrate species on the planet.

Learning more about how these species and their brains developed will shed light on the brain evolution of thousands of species.

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