310-million-year old footprints of a "lizard like-creature" have been unearthed in the Grand Canyon, making them potentially the oldest ever reptile footprints ever found.
It's unclear what creature left the set of 28 footprints behind, but it has been described as "a reptile-like creature" and were found by UNLV geology professor Stephen Rowland.
"It's the oldest trackway ever discovered in the Grand Canyon in an interval of rocks that nobody thought would have trackways in it, and they're among the earliest reptile tracks on earth," said Rowland, in a statement.
Rowland added that the tracks were created as the supercontinent Pangaea was beginning to form, noting "In terms of reptile tracks, this is really old."
The geologist, who was first alerted of the tracks by a colleague in 2016, initially believed they were from "two animals walking side-by-side" because of the sideways motion, but that did not make any sense. So he went home, researched and made drawings of his finding of the "peculiar, line-dancing gait" left behind by the animal.
"One reason I've proposed is that the animal was walking in a very strong wind, and the wind was blowing it sideways," Rowland said in the statement.
It's also possible that the slope was too steep and the animal sidestepped; other theories that have been thrown out are a fight with another animal or a mating ritual.
"I don't know if we'll be able to rigorously choose between those possibilities," he said.
Rowland and San Diego State University geologist Mario Caputo will publish the findings in January.
"It absolutely could be that whoever was the trackmaker, his or her bones have never been recorded," Rowland said.
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