Thoatherium
| Thoatherium | ||||||||||||
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Drawing life reconstruction of Thoatherium |
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| Temporal occurrence | ||||||||||||
| Miocene | ||||||||||||
| 20 million years | ||||||||||||
| Locations | ||||||||||||
| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Thoatherium | ||||||||||||
| Ameghino , 1887 | ||||||||||||
Thoatherium was a small ungulate that was foundin South Americain the Miocene , about 20 million years ago. Outwardly it resembled a small horse , but is not related to the horses ( Equus ), but belongs to the Litopterna , a group of the South American ungulates (Meridiungulata). Their equine likeness is a case of convergent evolution .
Like today's horses, Thoatherium was monophonic and resembled them in the morphology of the skull, legs and body. The degree of reduction of the side toes went beyond the proportions in horses. In contrast to modern horses, however, they retained the low-crowned, simply built teeth. The teeth, however, were lophodontic and more suitable for leaf-eating than for grazing. The clearly pronounced diastema (gap) between front teeth and molars in horses is only short in Thoatherium . It died out long before real horses reached South America.
literature
- Jens Lorenz Franzen : The primeval horses of the dawn. Origin and evolution of horses. Elsevier / Spektrum Akademischer Verlag, Munich et al. 2007, ISBN 978-3-8274-1680-3 .
Web links
- The Paleobiology Database: Thoatherium
