Scientists have confirmed a set of tracks found in 2016 in the Grand Canyon are 313 million years old.
A Norwegian geologist noticed the fossil while hiking along Grand Canyon National Park's Bright Angel Trail. The boulder bearing the fossil had fallen from a nearby cliff.
Paleontologist Stephen Rowland said the fossil shows tracks of two shelled, egg-laying animals walking over what was once a sand dune.
"These are by far the oldest vertebrate tracks in Grand Canyon, which is known for its abundant fossil tracks," Rowland said in a press release.
Rowland said the tracks are also among the oldest of their kind in the world and the earliest record of vertebrate animals walking on a sand dune.
Rowland's research dating the fossil was published this week.
