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Idaho SuperGraphic

The discovery

The area that is now known as the Hagerman Horse quarry (sometimes also referred to as the Gidley quarry) was excavated, and three tons of specimens were sent back to the Smithsonian in Washington, D.C. The material that the scientists uncovered was so extraordinary and the initial excavations were so successful that Dr. J.W. Gidley returned to Hagerman for several summers in order to expand the quarry. Because of Gidley's great success, the Smithsonian returned to Hagerman in 1931 with Norman H. Boss, who took over the operation after Gidley. During this time, the quarry floor had grown to 5,000 square feet, with a backwall 45 feet high. The excavation continued and many fossils were uncovered. The most important find was the large volume of a species of extinct horse known as Equus simplicidens, later dubbed the "Hagerman Horse." The Hagerman Horse was very important because it proved to be the largest sample of this extinct species from one locality. The operations in the quarry led to the discovery of five almost complete skeletons.

More than 100 skulls, 48 lower jaws and a variety of isolated bones were uncovered. In addition to the odd, horse-like bones, the Smithsonian also discovered bones from several other animals including beaver, otter, mastodon, frog, rabbit, turtle, birds and fish.

During the summers of 1932 and 1933, the Smithsonian did not do any work in Hagerman; however, the final expedition was made in the summer of 1934 under the leadership of Dr. C.L. Ganzin. Just as in past summers, a ton of ancient material was gathered at the horse quarry, and Ganzin published a major paper on the horse, based on the large sample from the quarry. Elmer Cook also did work for the Smithsonian during their excavations at the Hagerman Horse Quarry and continued to collect specimens even after 1934. In recognition of his many contributions, Ganzin named the newly discovered horse-like creature after him. Ganzin chose to do this because Cook was instrumental in bringing the fossils he found to the attention of the scientific community.

Related images

Men pose for picture with a giant rock in the quarry
Historic Smithsonian photograph. Initial findings in the horse quarry. Courtesy of the Smithsonian.
Men working in the quarry
Courtesy of the Smithsonian.

Mysterious bones America's first horse