Caption:
Gomphotherium, closely related to mastodons, disappeared before the end of the Pleistocene. The 3 m (10 ft) tall creature, also known as Trilophodon or Tetrabelodon, resembled a modern elephant but had four tusks instead of two: two on the upper jaw and two on the elongated lower jaw. The lower ones are parallel and shaped like a shovel and were probably used as such. Unlike modern elephants, the upper tusks were covered by a layer of enamel. These animals probably lived in swamps or near lakes, using their tusks to dig or scrape up aquatic vegetation. This specimen was found in Nebraska. Royal Tyrrell Museum, Alberta, Canada.