It is speculated that the rhino is as old as fifty million years, and all current offshoots occurred from the same, gigantic prehistoric grazer. Rhinos are ungulates, or herbivorous animals with three toes. There have been up to thirty different species of rhinos, but most of them are now extinct, due to poaching and deforestation. Now only five major species of the rhino still wander this planet, and all of them are varying degrees of threatened. Rhinoceroses are one of the few surviving ancestral creatures that date back before the Stone Age, and their appearance reflects this to a degree.
Common Ancestry
All rhinoceros have been traced back to their most common ancestry, from the Oligocene. Here two breeds of rhinoceros split from this line, giving us the two horned, or offensive horned rhino, and the single horned, or defensive horned rhino. The Indian rhino, which is the only surviving grazing species, is the closest direct descendant of the Oligocene. These few remaining species of rhino are the last of a vast and varied species that may have lived in almost any environment for Asia to Africa. The Sumatran rhino is thought to come from a separate line, more closely related to the wooly rhino, or coelodonta antiquitatis.
Last Leg Of The Species
The remaining species of the rhino are evidence of a creature that has continued to exist beyond its peak evolution period. Their massive size, another hallmark of a sub prehistoric creature, is more effectively suited to an environment rich with foliage and grazing territory. Because of their massive size and strength, the rhino is rarely the target of predatory attacks, even in the animal’s prehistory. Most fossil evidence suggests that most of these animals died in territorial rituals, or natural disaster. Until the proliferation of humanity, the rhino enjoyed continuous and rapid evolutionary prosperity.
Surviving Genetic Lines
Amynodonts, or defensive horned rhinoceros, proliferated the Eurasian and American continents, and were closely related to hippopotamus. These animals were partially aquatic and fed on seaweed and other underwater plant life. Sumatran rhinos still eat underwater plant life today, noting this a defense mechanism to combat scarce food resources. Aceratheres and paraceratheres rhinos are close genetic cousins of the large two horned rhinoceroses, and gave rise to some of the largest land mammals ever found. Fossils of these creatures suggest that they could have been as much as twice as large as a modern African elephant. The wooly rhinoceros was found to proliferate in northern Asia and what is known as Siberia today.
Continued Evolution
Scientist speculate that the rhinoceros is no longer suited to our environmental changes, and may not ever experience an evolutionary spike to compensate for continued changes. Fossil records show that the rhinoceros has not adapted to additional environments for close to five million years, and is never likely too. This means that, with or without human intervention, the rhino would likely not have survived more than a few million years anyway. However, humans are greatest influence in the extinction of the rhino. In the few hundred years that economic hunting practices took hold, this once far flung and genetically prolific creature, was nearly wiped out completely.
Summary
Although the evolution of the rhino is storied and far-reaching, is clear that this creature was not respected by man. While it is sad to see such a genetically diverse creature leave the face of our planet. While protection efforts are admirable, is increasingly difficult for them to survive.
