Curious Mind: Discovering the Hagerman Horse

2013-06-04T02:00:00Z Curious Mind: Discovering the Hagerman HorseKimberly Williams Brackett - Curious Mind Twin Falls Times-News

Q. Who found the Hagerman Fossil Beds and when were they developed?

A. “Elmer Cook, a rancher who was running cattle in what is now the monument, showed some fossil bones to Harold T. Stearns of the U.S. Geological Survey in 1928,” said Annette Rousseau from the National Parks Service. “Stearns, in turn, passed the fossils on to James W. Gidley of the Smithsonian Institution. During the summer of 1929, the two scientists excavated what became known as the Hagerman Horse Quarry. Three tons of specimens were sent back to the Smithsonian Institution in Washington, D.C.”

With four major excavations of the area conducted in the early 1930s, the quarry is recognized as one of six most important sites in the world regarding the fossil history of horses.

“Hagerman Fossil Beds became a national monument on Nov. 18, 1988,” said Rousseau. The Hagerman horse also became Idaho’s state fossil that same year.

Horses evolved in North America. A link between prehistoric and modern horses, the Hagerman Horse was the first true horse, but its bones most closely resembled Grevy’s zebra bones.

To protect the world’s richest known fossil deposits that existed before the Ice Age, the national park was given a legislative mandate to provide a center for continuing paleontological research and education.

A mounted skeleton of the world-famous Hagerman Horse is located in the visitor center.

The single largest sample of an extinct species of horse was discovered, along with more than 200 different species of fossil plants and animals, including saber-toothed cat, mastodon, bear, camel and ground sloth. More than 3,000 new fossil fragments are found each year.

A particularly rare fossil find was a humerus from the Hagerman mole, one of only a handful of mole fossils ever found in Idaho.

Approximately 195 species of birds have been reported. With relatively mild temperatures, many birds remain in Hagerman during the winter.

The monument is one of only four in the National Park system containing portions of the Oregon Trail.

The ancient shoreline of Lake Idaho stretched for 200 miles from Weiser to Twin Falls. The lake sediments deposited layers of sand, silt and clay at least 600-feet thick, preserving Pliocene fossils in the Hagerman Valley.

The fossils deposited in a stratigraphic record spanning 500,000 years appear to represent an entire paleontological ecosystem with a variety of habitats, such as wetland, riparian and grassland savanna. It includes plants and animals that lived in the Hagerman area about 3.5 million years ago in a wet and mostly forested floodplain.

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