During the Ice Age, large herds of giant mammals once dominated the landscape of what is now Kansas City. Most of the “giants” became extinct about 10,000 years ago, many leaving no descendants. Some, however, are represented by descendants of diminutive size. This exhibit compares skeletal remains of the Ice Age giants with their modern day relatives. Visitors will learn about the giant ground sloth, woolly mammoth, mastodon, saber-toothed cat, and the giant beaver. The exhibit was organized by Richard J. Gentile, Professor Emeritus at the University of Missouri-Kansas City. Dr. Gentile passed away on June 8, 2022. This exhibit, which features much of his life work, is now on permanent display at UMKC.

The exhibit incorporates skeletal parts and recreations of Pleistocene (Ice Age ) animals that were recovered from sand and gravel deposits of the major rivers and tributary streams of the area. The exhibit also includes fossils found in upland areas entombed in glacial sand and gravel deposits (outwash) and in wind-blown silt (loess). Pleistocene age elephants have been reported from over half of the 114 counties in Missouri and from numerous sites in Kansas. Voorhies (1990) estimates that no fewer than 10 mammoth skeletons lie buried in the average square mile of Nebraska landscape, an indication that large numbers of these huge proboscideans once roamed across the Central Mid-Continent.

The exhibit includes information on a variety of species, including ground sloths which first appeared in South America and gradually migrated into North America via the land bridge connecting the two continents that rose about 3 million years ago during the Pliocene Epoch. The species was given the scientific name Megalonyx jeffersoni in honor of President Jefferson, an amateur paleontologists, and one of the first to study extinct ground sloths. Two years before he became president, Thomas Jefferson published a description of an assortment of fossil bones including claws that had been excavated from a cave in West Virginia. Jefferson believed the claws were those from a large meat-eating animal that he named Megalonyx or “Great Claw” and instructed Lewis and Clark on their epic journey to explore the western part of the continent to watch for such a beast.

The following people and organizations contributed their time and talent to bring this exhibit to the Box Gallery:

Jonathan Kemper, Chairman Emeritus, Commerce Bank; Melissa Dehner, Illustrator, HoneyBee Creative; John Babcock, Illustrator, Babcock Designs, Robin Trafton, The Box Gallery; Gil Parker, Paleontology preparatory, Parker Paleontological Enterprises, Inc.; Denise Morrison, Director of Collections & Curatorial Services, Kansas City Museum; Megan Medley, Department of Earth and Environmental Sciences, University of Missouri-Kansas City.

The exhibit was funded through a generous grant from the William T. Kemper Foundation, Commerce Bank, Trustee, and administrated by the contract and grant specialists, most notably Carrie Stewart, Commerce Bank, and Jason Elliot and Elizabeth Wheeler, University of Missouri-Kansas City.

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