Mammals from White River formation
Oreodonts are the most numerous of the mammals found in the White River formation. They are sometimes described as appearing as a cross between a sheep and a pig. They have enlarged canine teeth which gives the skull a certain fierce look, but their molars show them to be well adapted to a diet of grass. Older Oreodonts frequently have extremely worn teeth. Oreodonts grazed in large herds during Oligocene times.
Oreodonts are Artiodactyls, even toed ungulates.
This is by far the most common of the oreodont species as well as the most common fossil from the White River formations. Note the complex teeth for grazing. Most teeth are highly worn, unlike this specimen.
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This fellow retains his canines, whuch are often the first to erode away. Rarer is the presence of several neck vertebrae. |
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A view showing the upper teeth of another specimen. The teeth are lightly worn, showing the complex occlusal surfaces for chewing grass. |
| Family: | Merycoidodontidae |
| Formation: | Brule (White River) |
| Epoch: | Oligocene |
| Size: | Sheep size |
Leptauchenia
The eyes and ears of Leptauchenia are at the top of the skull, suggesting an aquatic existence. However, Leptauchenia had deer-like hooves; not what one would expect for an aquatic animal.
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This skull is unfortunately nissing the front portion. |
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A well preserved lower jaw. |
| Family: | Merycoidodontidae |
| Formation: | Brule (White River) |
| Epoch: | Oligocene |
| Size: | Sheep size |