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AMERICAN FALLS, Idaho — To the untrained eye, the tracks along the western shore of the reservoir look fresh — odd in shape, but recent.

The fact is they were made by an ancient North American camel some 20,000 to 50,000 years ago, and the trail of tracks contains a treasure trove of information for paleontologists like Mary Thompson of the Idaho Museum of Natural History on the Idaho State University Campus.

Thompson was beaming with excitement recently as a dozen ISU scientists and graduate students explored the trackways discovered along the edge of American Falls Reservoir this month.

Preserved tracks found in the hardened sands included those of camels, llamas and a large dire wolf or Canis dirus. All lived during the Pliocene epoch when the large lake above American Falls provided water for creatures who enjoyed a cooler climate and a forested Southeast Idaho.

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“Camels originated in North America, as did llamas,” Thompson said.

Animals like camels and llamas provided a food source for predators like the dire wolf. This ancient canine was about 5 feet long and weighed about 130 pounds — slightly smaller than today’s timber wolf.

Thompson said determining the origin of predator tracks is more difficult because there were so many during that time period. Ancient bears and coyotes shared territories with the North American lion and two types of saber-toothed tiger.

The llama tracks discovered by ISU’s team are Hemiauchenia macrocephala or “bigheaded llamas.” The camels are Camelops hesternus or “yesterday’s camel.”

“This is one of the top locations in the nation for Pliocene vertebrates,” Thompson said about the area upstream from American Falls. “It’s just behind the La Brea Tar Pits.”

Her enthusiasm for the so-called “trackways” was shared by Robert Schlader, manager of the Idaho Virtual Lab at ISU’s museum. He was busy setting up sophisticated 3-D imaging equipment with two graduate students.

Schlader explained how the equipment uses lasers and a rotating mirror to create a three-dimensional image of the walkway.

“It’s essentially doing the same thing as policeman’s radar gun, except instead of measuring speed it measures distance,” Schlader said.

The grad students set up white balls along both sides of the walkway to serve as targets. Once the equipment has gathered all the data, Schlader will take it back to his lab and use it to create a virtual environment as it existed 20,000 or more years ago when the ancient animals were making tracks to the water’s edge.

“Our big goal today is to try to capture and document as much as possible of this,” Thompson said. “The trackways tell us a lot more about what the animals were doing,” Thompson said. “We’ll be at this for several days.”

And those several days of field work will translate into a more accurate glimpse of life in Southeast Idaho when a lava flow blocked the Snake River at American Falls and formed a large inland lake long, long before modern engineers did the same for irrigation.

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