Fossil ‘discovery’ rewrites history

Originally published in the Hays Daily News 21 February 2010

By MIKE CORN
mcorn@dailynews.net

For nearly 40 years, it’s been tucked away in a storage room at the University of Kansas, little more than a bag of bones that at the time it was collected struck even the most experienced as unusual.

The late Marion Bonner was right: The discovery in 1971 by his son Chuck then 21, was indeed unusual.

On Thursday, scientists announced that it was deserving of its own genus, proving to be something of a missing link between the oceans of 100 million years ago and today.

The announcement was made Thursday in Science Magazine.

The fossil, representing a massive filter-feeder much like the blue whale of today, was named Bonnerichthys, in honor of the Bonner family — responsible for outstanding fossil discoveries in the chalk bluffs of northwest Kansas.

Several of those discoveries are on display at Sternberg Museum of Natural History, as well as other museums.

The Bonnerichthys discovery came not from a recent collection, but from one that Chuck Bonner discovered in 1971 in Logan County while on a fossil-collecting expedition with his family.

“That was pretty nice,” Bonner said Friday. “Pretty nice to have a genus named after us.”

Several individual species have been named for Marion Bonner, who collected fossils alongside George Sternberg, founder of the Sternberg Museum.

While it was discovered by Chuck Bonner, the excavation work fell to his father.

“Dad knew when he was digging on it, it was something different,” Bonner said.

“I tell you what, I wasn’t too excited that day. Actually, I was more excited about Dana finding a turtle up above me.”

While the Bonner discovery — once it was cleaned up — was responsible for the naming of a new genus, there’s another and more complete specimen being prepared.

That discovery, coming from land owned by Mahlon and Carolyn Tuttle, has been donated to Sternberg and will provide even richer detail about the fish.

The Gove County specimen was discovered by Kenshu Shimada, an FHSU alumnus now at DePaul University in Chicago, and excavated by Mike Everhart, adjunct curator of paleontology at Sternberg.

Everhart has been thrilled with the credit given to the Bonner family, as well as the fossil that was collected in Gove County.

The trouble with plankton feeders is they are too much like sharks, in that they have little skeletal structure to fossilize. Much of it is cartilage and tissue.

Bones in the skull, for example, were connected by cartilage.

That made it big, but difficult to find, 100 million years later.

“It is the biggest bony fish feeding in the Cretaceous sea,” Everhart said. Generally, the Kansas variety, which makes up the largest percentage, would have been about 30 feet long.

The discovery, that it was a huge fish that fed on plankton, “filled in the blanks.”

Early on, the fish had been classed as a swordfish, but neither sword nor skull had been found.
Everhart said they have now determined that the fish lived from 170 million to 85 million years ago, dying out at the same time the dinosaurs.

“At the end of the Cretaceous, for some reason, the plankton died off,” Everhart said. That spelled doom for the filter feeders as well.

The chain of events have thrilled Everhart and Bonner.

“It’s very exciting to me,” Everhart said of the discovery and its publication in Science Magazine. “It’s not everyday you get a chance to be published in Science. It’s a pretty prestigious publication.”

Determining the fish was a filter feeder was just as significant.

“It was just an ‘aha’ moment,” he said. “We figured out what was going on.”

“He would have been swelling with pride,” Bonner said of his father.