Remains of extinct sea cow discovered at Komandorskie Islands
Steller’s cow (Hydrodamalis gigas) — is a mammal widespread during the last Ice Age. However, after that period, the inhabiting area of Steller’s cow dramatically decreased. Among hypothesis to explain such reduction is the supposition that the main reason is an unusual habit of life of sea cows together with the expansion of human in this region.
The Steller’s cow was a large animal measuring up to 7−10 meter longwise, weighing more than 5 tons approximately as terricole elephants. In addition to that, it inhabited only the shallow waters and apparently could not dive but only swim. It fed on with beach grass, primarily with laminaria. During the feeding, cows bore with limbs against the sea bottom.
The unique shallow surrounding area did not include any large sea carnivores. Therefore, the Steller’s cow was not afraid of any other creatures including human. This fact made the sea cow hunt very easy. The species was discovered at Komandorsky Islands (this was the only spot where sea cows lived after the end of Ice Age) in 1741 and by 1768 was extirpated entirely.
This is the first finding of such preservation quality since 1987. The skeleton could be discovered because of revealing several ribs. It was hidden by kidney stones and sand at a depth of 70 centimeters. The skeleton consists of 45 spinal bones, 27 ribs, left plate-bone, shoulder bones, and several carpus bones. The investigators have not found a skull, cervical spine, a couple of dorsal vertebra, several caudal vertebrae, bones of the right part of the pectoral arch, as well bones of metacarpal and phalangeal bones of the left limb.
Although the last finding of a complete skeleton of Steller' cow was done on the same Bering Island in 1987, the previously found skeleton measured only 3 meters. Larger species were discovered before XX century. Hence, the new finding will be one of the central showpieces of the visitor center of natural reserve «Komandorsky».
Previously, the paleontologists from Saint Petersburg University described a dinosaur egg who lived in West Siberian about 120 million years ago.