Steller's manatee
| Steller's manatee | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Steller's manatee skull |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name of the genus | ||||||||||||
| Hydrodamalis | ||||||||||||
| Retzius , 1794 | ||||||||||||
| Scientific name of the species | ||||||||||||
| Hydrodamalis gigas | ||||||||||||
| ( Zimmermann , 1780) |
Steller's manatee , Steller's manatee or giant manatee ( Hydrodamalis gigas ), formerly also called bark animal , is an extinct manatee of the northern Pacific .
It was first scientifically described by the German doctor and natural scientist Georg Wilhelm Steller in 1741 after Steller discovered it on an expedition under Vitus Bering . The expedition ship, the St. Peter , was stranded on the Bering Island off Kamchatka , which belongs to the commander's islands and was later named after the expedition leader . At that time there were probably only about 2,000 copies left on Bering Island and the neighboring Copper Island . Probably the last animal of the species was slain for food in 1768 by fur hunters near Bering Island.
features
Knowledge today is based on the meticulous descriptions of Steller and a number of skeletons in various museums.
The Steller manatee was up to 8 meters long and weighed up to 10 tons. The teeth were completely regressed in adaptation to the soft seaweed food; the animal ground the seaweed between two horny chewing plates with which the roof of the mouth was lined. The forearms ended in stunted metacarpal bones, the Steller manatee no longer had finger bones. Two stunted pelvic bones remained from the rear extremities, but anterior rudder fins were present, but they were much smaller than those of other manatees.
The Steller manatee had a transverse, forked caudal fin almost 2 meters wide. The skin was several centimeters thick to protect against damage to rocks and ice, had a thick layer of fat for insulation reasons and had a bark-like consistency, hence the name bark animal . The color was dark brown.
According to Steller's descriptions and current knowledge, the Steller's manatee seems to have had a low rate of reproduction, which accelerated its rapid extinction.
As the only one of the manatee species that lived in historical times, it was an inhabitant of cold water. In the Bering Sea , algae were the food of Steller's sea cow.
evolution
Presumably as a result of a cooling of the earth about 20 million years ago, a branch of the fork-tailed manatee, the hydrodamalinae, developed. In the Miocene , the genus Dusisiren , which represented this subfamily, was widespread in the Pacific. Three species of the genus Hydrodamalis are known from the Pliocene and Pleistocene , whose development ended in the Steller manatee.
distribution
The Steller manatee once inhabited the coast of the northern Pacific from Mexico via the Aleutian Islands to northern Japan . Possibly human hunting drove them to the inhospitable edge of their habitat, where, after being discovered by Bering's crew, it was wiped out by excessive hunting in just 27 years.
Exhibits
While around 20 skeletons still exist worldwide, only three pieces of Steller's manatee are known to have skin. One of them is in the St. Petersburg Zoological Museum, another is shown in the Overseas Museum in Bremen . A third copy is in the collection of the Julius Riemer Museum in Wittenberg . Skeletons can be seen in the German-speaking area in the Museum für Tierkunde in Dresden (also a model), in the Natural History Museum in Braunschweig and in the Natural History Museum in Vienna . In the Museum am Rosenstein in Stuttgart there is a skull cast and a small model. The Hessian State Museum Darmstadt and the Lower Saxony State Museum Hanover each have a skull. Casts of skulls are exhibited in the Überseemuseum Bremen and in the Senckenberg Nature Museum in Frankfurt am Main. The Alzey Museum also has a cast of a skull as part of the exhibition on manatees of the Tertiary Sea.
See also
literature
- Hans Rothauscher: The Steller's Sea Cow: Monograph of the extinct Nordic giant sea cow (PDF; 3.21 MB). Books on Demand, Norderstedt 2008, ISBN 978-3-8370-1793-9 .
Web links
- Overview page for Steller's manatee
- Hydrodamalis gigas in the endangered Red List species the IUCN 2006. Posted by: World Conservation Monitoring Center, 1996. Retrieved on 11 May, 2006.
Individual evidence
- ↑ Hans Rothauscher: Steller's sea cow in museums. In: The Steller manatee. Retrieved July 29, 2009 .