A pair of hikers walking through Valley of Fire State Park added a new chapter to our understanding of life in Nevada millions of years ago. A father and son who were climbing rocks came across tracks dating back to the Jurassic period. George Knapp originally reported on this discovery on August 5, 2003. Since this time several other tracks and many dinosaur bones have been discovered in the park.
MYSTERY WIRE — Freelance TV producer Steve Theodore and his son Evan were on one of their annual hikes through the Valley of Fire State Park when they noticed unusual markings on a remote Aztec sandstone ridge.
“I didn’t recognize it at first,” Steve Theodore said. But then it registered. These were very old tracks.
“I didn’t know there were dinosaur footprints out here,” Evan Theodore said. “We walked right over it and he was like, Evan, come look at this and I turned around and there’s dinosaur footprints everywhere. I’m like hey that’s cool.”
The tracks date from the mid-Jurassic period. This part of the United States looked nothing like what is seen in the movie, Jurassic Park. Here in the southeast corner of Nevada, the area was covered by massive sand dunes. It resembles the Sahara Desert of today. The animals that scampered up and down the dunes were likely were therapsids. It’s sort of a cross between mammals and lizards.
Therapsid, any member of a major order (Therapsida) of reptiles of Permian and Triassic time (from 299 million to 200 million years ago). Therapsids were the stock that gave rise to mammals. As early as the preceding Carboniferous Period (from 359 million to 299 million years ago), there appeared a distinct evolutionary line, beginning with the archaic mammal ancestors, order Pelycosauria, and leading toward mammals. From one pelycosaur family sprang the therapsids. Therapsids include mammals and other cynodonts; they form a subgroup of the Synopsida, one of the major branches of amniotes. Therapsids first appear in the Permian Period, during which they flourished and evolved into a number of mammal forms.Source: britannica.com
The red Aztec sandstone that can be seen at the park, are actually petrified sand dunes. Before the dunes the area was covered in a shallow tropical sea. The tracks are believed to be between 150 million – 200 million years old.
“The time that these tracks were made is a really interesting time in the history of life,” said Steve Rowland, a University of Nevada Las Vegas paleontologist. “It was the Jurassic period when the dinosaurs were the most dominant conspicuous terrestrial animals, but the mammals were also lurking around in the shadows and in the caves and in the trees.”
There are nine separate sets of tracks skittering up the ancient dune, suggesting these animals traveled in a pack or extended family.
Similar tracks were first found in Brazil. At the time the tracks were made, North and South America had just begun to split up and drift apart, which explains why the same animals existed on both continents. The Nevada environment back then was probably a vast sandy desert, part of which transformed into the Valley of Fire.
The scientists who’ve seen the tracks are genuinely excited about what we will learn from this.
“The exciting thing for me about this locality is it tells us new information to answer those very questions. We know very, very little about mammals and mammal-like reptiles that lived back in the Mesozoic era,” Rowland said.
“We have a few bones and a few teeth in different parts of the world, but the thing about tracks is it tells us something about behavior that you can’t get from the bones. We can actually see these animals moving. This particular locality might be one of the few, as far as I know, it’s the first in the world,” he said.
The exact location of the tracks will be kept secret to protect them. It’s not an easy place to get to anyway. Scientists have taken measurements and made impressions of the tracks both for study and so they can help the park build a public display so everyone can experience the amazing find.
“It is very cool. I think for the people of Nevada and for Valley of Fire State Park, it’s a very significant discovery,” Rowland said.
“I think they should name it after us,” Evan Theodore said.
Since this discovery, more tracks have been found in this area, and other areas in southern Nevada such as the Red Rock Canyon National Conservation Area just west of Las Vegas.
LEARN MORE: Pictures and Profiles of Therapsids