Dorudon
Dorudon | ||||||||||||
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Dorudon atrox , skeleton reconstruction in the Senckenberg Natural History Museum in Frankfurt am Main. |
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Temporal occurrence | ||||||||||||
Bartonian to Priabonian ( Eocene ) | ||||||||||||
40.4 to 33.9 million years | ||||||||||||
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Systematics | ||||||||||||
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Scientific name | ||||||||||||
Dorudon | ||||||||||||
Gibbes , 1845 |
Dorudon ( Syn . : Prozeuglodon ) was a primitive early whale thatlivedin the Middle Eocene . Fossils have been found near the Fayum oasisin Egypt ( Valley of the Whales - Wadi al-Hitan ), in Tunisia and in South Carolina . Dorudon then appeared in the western Atlantic and in the Tethys . There are two valid species: D. atrox from North Africa and D. serratus from South Carolina. All other species described have been synonymous with these.
features
Dorudon reached a length of five meters, with the skull becoming 60 centimeters long. The skull was not particularly elongated, the brain was relatively small, and there was no melon organ . Its teeth were heterodontic , the rear teeth provided with saw-like edges. The neck was still relatively long and flexible, the pelvic region elongated and provided with strong muscles. The caudal stalk spine was not tapered. Dorudon probably had a fluke , but it has not been preserved in fossil form. The upper arm bone (humerus) was much longer than the spoke , and the elbow joint was movable. The front leg bones were thin and cancellous , the front legs turned into fins. In contrast to today's whales, Dorudon still had fully developed, but very small, hind legs. They had no contact with the pelvis . Compared to recent whales, Dorudon was probably a poor swimmer.
Systematics
Dorudon is related to the 18-meter-long Eocene whale Basilosaurus and, like this, belongs to the Basilosauridae family . Within the Basilosauridae, Dorudon forms the subfamily of Dorudontinae with some other smaller species .
Web links
- The Paleobiology Database Dorudon
- Palæos: Dorudon
- PD Gingerich: Research on the Origin and Early Evolution of Whales (Cetacea)