Ancestral rhinoceroses are held to have first diverged from other perissodactyls in the Early Eocene. Mitochondrial DNA comparison suggests the ancestors of modern rhinos split from the ancestors of Equidae around 50 million years ago. The extant family, the Rhinocerotidae, first appeared in the Late Eocene in Eurasia, and the ancestors of the extant rhino species dispersed from Asia beginning in the Miocene.
The Indian and Javan rhinoceros, the only members of the genus Rhinoceros, first appear in the fossil record in Asia During the Early Pleistocene. The oldest known record of the species is from Early Pleistocene (~1.5 Ma) deposits at Trinil, Java. Molecular estimates suggest the two species diverged from each other much earlier, around 11.7 million years ago. Although belonging to the type genus, the Indian and Javan rhinoceroses are not believed to be closely related to other rhino species. Different studies have hypothesized that they may be closely related to the extinct Gaindatherium or Punjabitherium. A detailed cladistic analysis of the Rhinocerotidae placed Rhinoceros and the extinct Punjabitherium in a clade with Dicerorhinus, the Sumatran rhino. Other studies have suggested the Sumatran rhinoceros is more closely related to the two African species.The Sumatran rhino may have diverged from the other Asian rhinos 15 million years ago, or perhaps as far back as 25.9 million years ago (based on mitochondrial data)
