|MadSci Network: Evolution|
Elephants and rhinoceros are perfect examples of recent mammal history, Mr. Anonymous! So here is the story.
The woolly species is just one rhinoceros that lived during the last Ice Age in Pleistocene Siberia and was also common later over most of northern Europe and Asia till just 10,000 years ago. That explains why it might have been woolly. It had molar and other teeth containing large grooves or cavities and it is named after this feature, feeding on tundra plants such as grasses and sedges.
You make a mistake in assuming that there is only one type of rhinoceros still living. The species we have are different in size, number of horns (Old Woolly had 2) and diet. They in fact are ancestors or more likely descendants from creatures like the Coelodonta or woolly rhinoceros that you refer to (about 3 species). Your common woolly one is called Coelodonta antiquitatis.
The small Sumatran rhino is the nearest relative of the Woolly and it is quite hairy because it can live high on mountains in Borneo and Sumatra. It is called Dicerorhinus sumatrensis because it also has 2 horns, but it's almost extinct too (only 275 left)! The other 2- horned rhinos live in Africa, the weid (or white) rhino and the black, but they come from a different part of the family and have features like no teeth at the front of their mouths.
Many more rhinos existed at the time that woolly and Sumatran rhinos first appeared. This was a period called the Miocene, when there were smaller and faster rhinos, very large creatures called Indricotherium and very aquatic rhinos, just like hippos, as well as the many ancestors of the modern types.
Truth, as far as fossil evidence is concerned is certainly stranger than any fiction that anybody has ever written!
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