The Black Rhino has a rich and fascinating evolutionary history. The Rhino is one of the oldest living species, having already existed for an estimated 2 million years. Both the Black and White Rhinos evolved from the same common ancestor, the Ceratotherium neumayri.
The skull of the Ceratotherium neumayri.
Fossil evidence shows that Ceratotherium neumayri were present in Africa an up to 23 million years ago. It is believed there was a split around 5 million years ago where the black and white rhinos’ direct ancestors evolved. The ancestor just before the Diceros bicornis is Diceros praecox.
A model of Diceros praecox.
The evolutionary tree of the Rhino family
The Black Rhino Lover Blog 
Dillon, There are many mistakes on this page. Species names MUST be italicized. The black rhino has a rich and fascinating WHAT? What do you mean by “The Rhino is one of the oldest dated species, having already existed for an estimated 2 million years”? This is not written correctly. Your images and evolutionary tree are great, but you
need to make them larger – especial the evolutionary tree chart. Notice how all the species names are italicized in the chart. Lots of typos. See me, and I will help you fix this page.