These Rocks Made a 1,000-Mile Trek. Did Dinosaurs Carry Them?

Researchers suggest a collection of prehistoric stones found in Wyoming journeyed from Wisconsin in the bellies of very large beasts.

In the summer of 2017, Joshua Miller, then an undergraduate at Augustana College in Illinois, visited a field research camp in Wyoming and picked up some rocks. Rounded at the edges and the size of small fists, they were out of place amid the fine-grained mudrock that had surrounded them, and Mr. Malone asked his father, David Malone, a geologist at Illinois State University who led the dig at the site, if he knew where the rocks had come from. Four years later, the two have developed a surprising answer. In a study published earlier this year in the journal Terra Nova, the Malones with colleagues say the stones came from a rock formation in southern Wisconsin about 1,000 miles to the east of where they were found. What’s even more surprising is their hypothesis for how the rocks made that journey: The researchers say they were carried in the guts of long-neck dinosaurs.