SCIENCE -FOSSIL'S- SCEPTRE : LAB

The Worms Take Over

Insights to be gleaned from a fossil's missing brain

It's a dubious distinction in the fossil record : For the first time, a vertebrate has been found with fecal pellets where its brain once was. {Invertebrates have produced such specimens for hundreds of millions of years.}

The fossilized vertebrate was Astroscopus countermani, an extinct fish first described as a separate species in 2011 in Maryland.

Also known as a stargazer, because its eyes were on top of its head, it was about the size of today's trout and the earliest known member of its family and its genus. Such fish still prey on seafloors all over the world.

Approximately 7.5 million to 10.5 million years ago, this stargazer specimen died, and its braincase appears to have been infiltrated by polychaetes or other annelid worms.

The creature may have scavenged the dead fish's brain, leaving a profuse amount of excrement in their wakes.

''This,'' said StephenJ. Godfrey the curator of paleontology at the Calvert Marine Museum in Maryland and an author of the study,'' was an overachieving worm or worms that burrowed into this little fish!''

Technology has enabled the authors to peer inside both the braincase and the fossilized pellets without destroying either. In a new paper, the scientists describe using a spectroscopic device to confirm the calcium and phosphate signatures of fossilized feces in the fish's braincase.

Aline Ghilardi, a paleontology professor in Brazil who was not involved in the research, said that small creatures and what they leave behind - burrows or bodily waste - can provide detailed stories about environmental changes over time.

''Each type of a fossil has a different story to tell,'' she said. [ Jenne Timmons ]