Steller's sea cow

Skull of Steller's Sea Cow

Steller's Sea Cow, Steller's sea cow or Riesenseekuh ( Hydrodamalis gigas ), formerly also known as Borken animal, is an extinct sea cow of the northern Pacific.

She was described in 1741 by German physician and naturalist Georg Wilhelm Steller first time scientifically, after St. Peter's, the expedition ship of Vitus Bering, was stranded at the now named after him Bering island off Kamchatka. At the time there were probably only about 2,000 copies in the Bering Island and the adjacent copper island. Probably the last animal of the species was killed for food in 1768 by fur hunters in the Bering Island.

Features

Today's knowledge based on meticulous descriptions Steller and a number of skeletons in various museums.

The Steller's sea cow was up to 8 feet long and up to 10 tons. The teeth were completely regressed in adaptation to the soft seaweed food; the animal rubbed it between two horny chewing plates with which the palate was lined. The forearms ended in vestigial metacarpal bones, finger bones no longer had the Steller's sea cow. Of the two hind limbs vestigial pelvic bones were left, whereas forward rudder fins were present, compared with those of other manatees but greatly reduced. The Steller's sea cow had a transversely asked, forked tail fin of nearly 2 meters in width. The skin was to protect against injuries from rocks and ice several inches thick, possessed of isolation reasons, a thick layer of fat and had a bark- like consistency, hence the name Borken animal. The color was dark brown.

After Steller descriptions and current knowledge, the Steller's sea cow seems to have had a low reproductive rate, which favored its rapid extinction.

As the only living in historic times Seekuharten this was a resident of cold water. In the Bering Sea algae were the food of the Steller's sea cow.

Evolution

Probably as a result of Erdabkühlung about 20 million years ago, a side branch of dugongs made ​​out, the hydro Dama Linae. In the Miocene the genus Dusisiren that represented this subfamily, widespread in the Pacific. From the Pliocene and Pleistocene, three species of the genus Hydrodamalis are known whose development ended in the Steller's sea cow.

Dissemination

The Steller's sea cow once inhabited the coasts of the northern Pacific Ocean from Mexico to the Aleutian Islands to northern Japan. Maybe they drove the hunting by humans to the inhospitable edge of their habitat, where it was eradicated after the discovery by Bering's crew in just 27 years by excessive hunting.

Exhibits

While still about 20 skeletons exist worldwide, only three pieces of skin of the Steller's sea cow are known. One of them is in the Zoological Museum in St. Petersburg, the other is shown in Überseemuseum Bremen. A third copy is in the Julius Riemer Museum collection in Wittenberg. Skeletons are in German-speaking at the Museum of Zoology Dresden ( also a model ), the Natural History Museum in Braunschweig, and to see the Natural History Museum in Vienna. In the museum at Rosenstein in Stuttgart there is a skull cast and a small model. The Hessian State Museum in Darmstadt has a skull.