Desmostylia
| Desmostylia | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Paleoparadoxia tabatai skeletal reconstruction |
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| Temporal occurrence | ||||||||||||
| Late Oligocene to Tortonian ( Miocene ) | ||||||||||||
| 29 to 7.25 million years | ||||||||||||
| Locations | ||||||||||||
| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Desmostylia | ||||||||||||
| Reinhart , 1953 | ||||||||||||
The Desmostylia are an extinct group of aquatic mammals . They are known from the late Oligocene and Miocene and presumably only lived on the North Pacific coast .
features
Desmostylia reached body lengths of up to 1.8 meters, their weight is estimated to be up to 200 kilograms. In their physique, they show certain similarities with hippos . Her physique was strong and her fore and hind limbs were well developed. The feet were remarkably wide and possibly developed paddle-shaped. Their teeth are remarkable: incisors and canines protruded forward like tusks, behind them there was a large gap (diastema), the molars were cylindrical.
Way of life
Desmostylia lived on the coasts of the North Pacific, fossil finds are documented from Japan , Mexico and the USA . In contrast to the closely related manatees , they were probably still able to move on land; their way of life is compared to that of the sea lions . They presumably stayed on land to mate and sleep while they looked for food in the water.
The purpose of their teeth, which are unique in the mammal kingdom, is largely unknown. They may have used it to graze seaweed.
Systematics
The Desmostylia are classified in the mammal group of the Paenungulata , their closest relatives still living today are the elephants and the manatees . Since their co-living relatives were largely confined to Africa, it is unclear how these animals got to the North Pacific.
literature
- TS Kemp: The Origin & Evolution of Mammals. Oxford University Press, Oxford 2005. ISBN 0-19-850761-5
Web links
- Further information
- The Paleobiology Database Desmostylia