Scientists Confirm Oregon’s First Dinosaur Fossil In State History

Scientists Confirm Oregon's First Dinosaur Fossil In State History
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It may have only been a comparatively small toe bone, but University of Oregon scientists recently confirmed that they have discovered the state’s first-ever dinosaur fossil, one that dates back over 100 million years ago to the Cretaceous Period.

According to a report from the Eugene Register-Guard, the toe bone was first discovered in the summer of 2015, when University of Oregon earth sciences professor Greg Retallack spotted it in the small Eastern Oregon town of Mitchell. The tiny fossil is thought to have belonged to a plant-eating ornithopod that measured at least 20 feet long and weighed in at about a ton. The dinosaur is believed to have existed about 103 million years ago, around the same time as the fearsome Tyrannosaurus rex.

“This bone was sitting out there with all the rocks. It was pretty surprising,” Retallack told the Register-Guard.

“No excavation was needed. It was just sitting among the ammonites and coil fossils.”

University of Oregon Museum of National and Cultural History paleontological collection manager Edward Davis, who worked with Retallack on a study documenting the find, said that the ornithopod might have spent most of its life in the water before dying onshore and washing out to the sea.

As further noted by the Register-Guard, the fossil measured only one inch long and two inches wide, and was specifically found in a marine rock. Retallack said that this was unusual because those same rocks had previously yielded fossils of flying and marine reptiles, but no evidence that actual dinosaurs existed in the location.

For the next three years that followed the initial discovery, Retallack teamed up with a group of University of Oregon researchers to conduct follow-up studies on the fossil and confirm whether it was really a dinosaur bone or not.

After UO Museum of National and Cultural History curator of paleontology Samantha Hopkins examined the fossil and concluded that it belonged to an ornithopod, the researchers returned to the site of the discovery for additional documentation. Retallack then compared the bone against dinosaur fossils in various North American museums to finalize his team’s findings and to get a “really good idea about what [the fossil] was and what it wasn’t.”

The UO team finished its research in October 2017 and waited a year before the study was fully peer-reviewed and published in the Journal of Vertebrate Paleontology.

“[The toe bone was the] first diagnostic nonavian dinosaur fossil from Oregon, a state whose Mesozoic rocks are mostly marine. This discovery is novel evidence of Cretaceous terrestrial environments and faunas in Oregon,” read a passage from the paper, as quoted by the Register-Guard.

While it remains unclear whether the same site in Eastern Oregon is home to other dinosaur fossils, Retallack hinted at another potentially interesting find from the same area, though he declined to share the specifics of the newer discovery. As for the toe bone, the Eugene Register-Guard wrote that it will likely be displayed in the UO Museum of National and Cultural History’s new acquisitions case in December, and showcased early next year at an exhibit focusing on how Oregon has not been a traditional hotbed for dinosaur fossils.