“Conodonts are marginally related to fish, but not really fish like we think of them,” said Nicole Peavey, a Texas Tech University researcher who has been studying conodonts. “They’re kind of like eels or hagfish or lampreys, but different. They may be close in shape and lifestyle, but it’s not a perfect comparison. That’s like comparing a modern mammal to a dinosaur. Conodonts went extinct at the end of the Triassic Period, about the time dinosaurs were evolving. The group is gone, which makes them very mysterious. They don’t have any living relatives to compare them to.”

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One reason why conodonts have remained so enigmatic, despite the fossil finds, is that their soft bodies didn't leave much to make fossils. The same happened to prehistoric sharks, so scientists are left with very sketchy evidence to go on.

In the 1980s, however, paleontologists found full fossilized conodont specimens, and only recently have scientists begun to unravel their secrets.

“They’re really interesting animals,” Peavey said. “No one knew what the animal looked like until fairly recently. They’re a couple inches long, kind of skinny with a complicated set of teeth. Those teeth are what paleontologists find. Even before paleontologists knew what they animal looked like, they were important because their teeth served as geological markers for economic geology, such as finding oil, and for correlation, where geologists match rocks from one area with rocks for another area.”