gene) suggested that the Hystricidae (Old World porcupines), Phiomorpha, and Caviomorpha (which includes New World porcupines) lineages split some 63 to 43 million years ago. This supported a single colonization event of South America by hystricognaths. A 2013 study of nuclear and mitochondrial genomes supports a mid-Eocene diversification of New World hystricognaths, with family-level splits occurring in the early Miocene.

Fossils belonging to the genus Hystrix date back to the late Miocene