Beginning about 5 million years ago , they were gradually replaced by modern elephants , but the last two South American species , in the genus Cuvieronius , did not finally become extinct until possibly as recently as 9,100 BP , and Stegomastodon remains have been dated as recently as 6,060 BP in the Valle del Magdalena , Colombia .
Stegomastodon remains have been dated as recently as 6,000 years ago in the Valle del Magdalena , Colombia .