Feature Ecosystems How mammoths competed with other animals and lost Human hunters helped wipe out mammoths, mastodons and gomphotheres MAMMOTH WORLD A Columbian mammoth (Mammuthus columbi), an American mastodon (Mammut americanum) and a gomphothere (Cuvieronius) were among the prehistoric elephant relatives that roamed North America and Eurasia until the end of the last ice age. Sergio De La Rosa Share this:EmailFacebookTwitterPinterestPocketRedditPrint By Alexandra Witze November 13, 2018 at 1:30 pm The Gray Fossil Site, a sinkhole in northeastern Tennessee, is full of prehistoric treasures.