Three dinosaurs that were thought to belong to very different groups are actually kids, teens and adults of the same genus, researchers say.
“I made a brand new dinosaur hall at the museum three years ago, and now I have to change it,” says Jack Horner of the Museum of the Rockies in Bozeman, Montana, an author of the study. “We’ve named twice as many dinosaurs as there probably are.” Horner and his colleagues report the findings in the October 28 PLoS ONE.
The trio falls under the umbrella of pachycephalosaurs, or thick-headed dinosaurs. They were neighbors in both place and time: All three hailed from what is now the Hell Creek rock formation in Montana and South Dakota, and all three died around 65 million years ago.