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The Hypnotic Whorl of Teeth That Keeps Researchers Guessing

How many facelifts can one extinct animal undergo? The answer is probably equal to the number of interested researchers and paleoartists out there, and then some.

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


How many facelifts can one extinct animal undergo? The answer is probably equal to the number of interested researchers and paleoartists out there, and then some. In the case of the mysterious whorled tooth rows left behind by the fossil fish known as Helicoprion, artist Ray Troll has documented close to two dozen, many of which were his own attempts to bring the creature out from behind the shrouds of time:

Part of the problem with Helicoprion fossils is that they are only known from the teeth. With one notable exception, no evidence remains of what these cartilaginous fish looked like - cartilage just doesn't fossilize as reliably as bone. So for over a century, researchers have wrestled with how exactly the bizarre saw-like teeth fit in the jaws of these creatures.

Recently, however, researchers at the Idaho Virtualization Lab (IVL) at Idaho State University took a closer look at the one specimen that was noted in 1966 to have some remnants of the jaws preserved in the block surrounding the tooth whorl. At the urging of Troll, who was friendly with the researcher who had noted this fact in the '60s, the IVL had the fossil CT scanned. Sure enough, after analyzing the data, they found evidence of an upper and lower jaw surrounding the tooth whorl, adding some much-needed evidence to the debate about how long Helicoprion's snout was and where and how the unique tooth row sat in the jaws.


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The results are on display in an exhibit at the Idaho Museum of Natural History in Pocatello, ID through April, when it should start a cross-country tour (if your curiosity is whetted and you want it to visit your town, contact your local natural history museum as they are currently accepting bids. Perhaps your city could be the first on the tour?!) The exhibit is full of the wild and wonderful art of Ray Troll and features an animatronic jaw that shows just how this bizarre arrangement of teeth likely worked. There is also a life-sized model by paleosculptor Gary Staab crashing through the exhibit walls. It's not to be missed.

Exhibit Details & Links:

The Whorl Tooth Sharks of Idaho

Idaho Museum of Natural History

now through April 2014

921 S 8th Ave.

Pocatello, Idaho 83201

A sampling of the art on exhibit by Ray Troll

Idaho Virtualization Lab

Article: "Idaho State Researcherssolve mysteries of ancient “shark” w/ spiral-toothed jaw; results published in Royal Society’s journal Biology Letters"

Ray Troll portfolio

Gary Staab portfolio

All art and images by Ray Troll, unless otherwise indicated.