UNLV researchers puzzle over tracks left near Gold Butte that predate dinosaurs

By HENRY BREAN LAS VEGAS REVIEW-JOURNAL

8 years ago

Fossilized reptile tracks march across a sandstone slab about 115 miles northeast of Las Vegas in this photo taken Feb. 7. UNLV geology professor Steve Rowland said the footprints were laid down about 290 million years ago, “give or take a million years or so.” (Steve Rowland/UNLV)

During a Feb. 7 research trip to the Gold Butte area northeast of Las Vegas, UNLV undergraduate students, from left, Stephanie Vosburgh, Summer Matz and Cameron Rickerson examine the fossilized tracks of an unknown reptile that lived and died some 60 million years before the earliest dinosaurs. (Steve Rowland/UNLV)

Fossilized footprints from an unidentified reptile run eastward along a slab of sandstone in this photo from Feb. 7 in the Gold Butte area of northeastern Clark County. UNLV researchers recently announced the discovery, which may rank as the oldest vertebrate tracks ever found in Nevada. (Steve Rowland/UNLV)

Fossilized reptile tracks 60 million years older than the earliest dinosaurs are preserved in a sandstone formation in the Gold Butte area northeast of Las Vegas, shown here in a photograph from Dec. 13, 2014. (Steve Rowland/UNLV)

Roughly 290 million years before rancher Cliven Bundy brought international attention to the Gold Butte area, an early reptile the size of a baby crocodile left its own lasting impressions there.

A team of researchers from UNLV recently announced the discovery of fossilized footprints 60 million years older than the earliest dinosaurs on a slab of sandstone about 115 miles northeast of Las Vegas.

The tracks march eastward across the rock for a little over two feet — six strides in all from a four-legged creature with three distinct toes on its back feet. Ripples around some of the prints show where the unidentified reptile’s feet sank into the soft wet surface of a vast tidal mud flat that covered the area back then.

“We have 12 pretty well-preserved footprints,” said Steve Rowland, a paleontologist and geology professor now in his 39th academic year at UNLV.

There are 12 footprints instead of 24, Rowland said, because the tracks from the animal’s back feet cover over the tracks left by its front feet.

“If it did have a tail — and it might well have — it didn’t drag it in the mud,” he said.

The ancient footprints on public land were actually discovered about two years ago by Mesquite resident Tom Cluff, a retired U.S. Forest Service employee turned amateur paleontologist who also serves on the board of the Friends of Gold Butte, an advocacy group pushing for permanent protection of the area.

Rowland said this wasn’t the first find for Cluff, who has developed a keen eye for spotting ancient footprints.

“Often it’s the hikers who find these things and tell me about them,” he said.

Rowland and his students began studying the tracks last fall, then returned in the site in February to document it in detail.

He and three students presented their findings for the first time Oct. 27 at a meeting of the Society of Vertebrate Paleontology in Salt Lake City. They are now at work on a full study they hope to submit for publication in a peer-reviewed journal early next year.

Rowland said the tracks could rank as the oldest vertebrate footprints ever found in Nevada, but that’s not what makes them interesting from a scientific perspective.

‘A MORE COMPLICATED STORY’

They resemble those generally found in rocks millions of years younger, when the landscape was covered in dry sand dunes. Rowland said it’s unexpected — maybe even unprecedented — to find tracks like this in rocks so old.

“It tells us that it’s a more complicated story than we thought,” he said. “That’s part of the fun. Just when you think you’ve gotten things figured out, something comes along that leaves you scratching your head.”

Based on the size and distribution of the tracks, Rowland said the reptile that left them was probably about 2 feet long. It was most likely a carnivore, he said, but “what this animal was eating I have no idea.”

Rowland declined to pinpoint the exact location of the remote fossil site, except to say that getting there requires about 30 minutes of driving on dirt roads and at least an hour of hiking.

For more than a decade, conservationists have advocated for heightened federal protection of the Gold Butte area.

The roughly 350,000-acre swath of northeastern Clark County is home to ancient rock art galleries, sweeping desert vistas and twisted fields of pastel-colored sandstone hemmed in by Lake Mead and the Grand Canyon. It is also the site of a long-simmering public land dispute involving the Bundys and their cattle, which were left to graze on federal range land without permit or payment for more than 20 years.

Though Republican members of Nevada’s congressional delegation loudly opposed the idea, outgoing Senate Minority Leader Harry Reid, D-Nev., has made it his mission to persuade President Barack Obama to designate Gold Butte as a national monument before both men leave office early next year.

As far as Rowland is concerned, the area deserves “some sort of special protected status” beyond what exists there now. These ancient fossilized footprints only bolster that argument, he said.

“I think this is a really good example of what some of the unknown treasures of Gold Butte are.”

Contact Henry Brean at hbrean@reviewjournal.com or 702-383-0350. Follow @RefriedBrean on Twitter.