Brontotherium leidyi Skull Lower Jaw Early Oligocene Chadronian Chadron Formation Squaw Creek Nebraska

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Brontotherium ('thunder beast') is an extinct genus of prehistoric odd-toed ungulate mammal of the family Brontotheriidae, an extinct group of rhinoceros-like browsers related to horses. The genus was found in North America during the Late Eocene. Many Brontotherium remains have been found in South Dakota and Nebraska. In the past, specimens exposed by severe rainstorms were found by Native Americans of the Sioux tribe. The Sioux believed these creatures produced thunderstorms when running over the clouds, and called them 'thunder horses'. Many of the skeletons found by the Sioux belonged to herds which were killed by volcanic eruptions of the Rocky Mountains, which were volcanically active at the time.

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Size: 3988px × 3811px
Photo credit: © Phil Degginger / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: ancient, archaic, beast, brontotherium, chadron, chadronian, creek, early, eocene, extinct, formation, fossil, fossilization, fossilized, fossils, herbivore, jaw, leidyi, mammal, nebraska, oligocene, paleontology, prehistoric, preserved, record, rhinoceros-, skull, squaw, thunder, titanothere