he key to fame for Hipparion is the amazing success that this genus exhibited. Although perhaps nothing special in terms of appearance, Hipparion appeared at the start of the Miocene period and continued to thrive until well into the mid Pleistocene, surviving for some twenty-two million years. In the space of this time Hipparion colonised most of the major continents with the exception of Antarctica, Australia and South America. The former two were separated by sea preventing land animals from colonising these continents. South America was not joined to North America until the creation of the Isthmus of Panama in the late Pliocene, and since North American remains of Hipparion are dated to the end of the Miocene at latest, it’s probable that Hipparion was not around in this continent at a time to take part in the Great American Interchange which saw a mixing of previously isolated animals, thus missing the chance to colonise South America as well.