How the forces of nature and luck led to the discovery of the 163 million year old “fish lizard” in Utah
Alan Dailey from Hooper, pictured with the sandstone block with the ichthyosaur fin, vertebrae and ribs, just before a team collected the fossil from Flaming Gorge on September 8th. Dailey found the fossil while boating in May. (Utah State Parks)
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VERNAL – Alan Dailey was out on the boat at Flaming Gorge Reservoir in May when he came across something strange.
When the Hooper man stopped near the shore and looked at the rocks in front of him, he noticed bones in a 400-pound block of sandstone sticking barely out of the water about 15 to 25 meters from the shore.
“It was basically up on the beach, so if the reservoir was full, this thing would have been right on the water’s edge,” said John Foster, curator at the Utah Field House of Natural History in Vernal.
Dailey took photos of the rock and quickly thought of sending it and his GPS coordinates to James Kirkland, the state paleontologist for the Utah Geological Survey. This information was passed on to the Utah Field House of Natural History at Vernal, which eventually traveled to the site to find out what caught Dailey’s attention.
There, according to Foster, the crews found a fossil with a front forefin, 19 movable vertebrae and 10 ribs. Utah paleontologists checked the specimen and found that it matched a unique prehistoric creature known as the ichthyosaur, a name that means “fish lizard”. The animal was essentially a fish and lizard combination that existed in the late Jurassic about 163.5 to 145.5 million years ago.
“The ichthyosaurs looked more or less like a reptilian dolphin,” said Foster. “They had the same short torpedo-shaped body, dorsal fins, pectoral and pelvic ends, a long snout with conical teeth for fish-eating. The main difference was that their tail was more vertical than flat like a dolphin, and that just has to be with the different one How mammals move compared to reptiles. “
An artist’s impression of what an ichthyosaur looked like. An icthyosaur fossil found in the Flaming Gorge in May is believed to be around 163 million years old. (Photo: Utah State Parks)
The ichthyosaur discovered in the Flaming Gorge is believed to be around 163 million years old. State crews recovered the fossil on September 8, and it is currently being prepared in a laboratory in eastern Utah.
A lucky find
The fossil find was the result of two forces of nature – with a pinch of luck. As a result of the Utah drought, the Flaming Gorge was not 100% occupied when it was found. If the reservoir was completely full, Dailey might never have come across the fossil when he did.
But unlike other drought-related reservoir discoveries, erosion was the main reason behind the discovery. Experts believe the 400-pound block of sandstone fell a short distance away from vertically lying rocks above the water in the area where it was discovered.
“As that sandstone weathered, this block essentially fell onto the beach from an essentially vertical position,” said Foster, adding that it had likely only been visible for a short time when Dailey spotted it.
You couldn’t have seen the fossils if they landed the other way … Landing the (fossil) side up was definitely a good thing.
–John Foster, Utah Field House of Natural History
How it ended up in the water was a stroke of luck that made Dailey’s discovery possible. When it fell, the rock landed with the fossil on the outside. It made it possible for a boat driver to come over and see it.
“You couldn’t have seen the fossils if they had landed the other way,” said Foster. “It’s such a big block that no one could turn this thing over and see that there could be an ichthyosaur fin and vertebrae on the other side. Landing (fossil) on top was definitely a good thing. “
Crews unload the ichthyosaur block found in the Flaming Gorge in the Lucerne Valley Marina near Manila, Daggett County on September 8, 2021. (Photo: Utah State Parks)
Transportation to the Utah Field House of Natural History took a little work. A crew of about a dozen workers – paleontologists, U.S. Forest Service personnel, Utah Field House of Natural History volunteers, and Dailey – were finally able to wrestle the 400-pound block of sandstone out of the water and back to the bank, where a forklift was used to unload the rocks from a boat onto a truck.
How you can see the fossil
A team from the Utah Field House of Natural History is currently preparing the fossil so that it will eventually be displayed at the Vernal Museum. Visitors can see it being prepared in the facility’s laboratory while a team prepares it for an exhibition, according to the museum.
While eastern Utah is known for dinosaur finds, the ichthyosaur fossil joins a 152 million year old log, as the most recent fossil finds in the region were brought to the Utah Field House of Natural History. Both finds are older than most of the dinosaur bones paleontologists have unearthed.
Foster said the two most recent discoveries will help them better understand the entire environment that existed in the age of the dinosaurs.
“The ichthyosaur reminds us that there were sea lanes in the same region (as did dinosaurs) and the ichthyosaur – although a few million years older than the dinosaurs in Dinosaur National Monument – somehow shows that these marine reptiles existed at the same time like the dinosaurs, “he said.” They have taken on these ecological roles that are very similar to what mammals now play. “