Scientists from Russia will help revive extinct sea lions
Researchers from Russia and South Korea conducted the first large—scale study of the genetic history of Dokdo sea lions (Japanese sea lions), extinct marine mammals that were widespread until the middle of the 20th century in the southern Sea of Japan.
"The number of Tokto sea lions used to be tens of thousands of individuals, but in the first quarter of the 20th century there was a sharp decrease in their number. The reason is the intensive extraction of meat, skins and fat of these animals, which is associated with the period of occupation of Korea by Japan. In particular, females and cubs were exterminated for profit," Artyom Nedoluzhko, co—author of the study and scientific director of the paleogenomics laboratory at the European University in St. Petersburg, told Izvestia.
As a result, the scientist added, there were only 50-60 Tokto sea lions in the 1950s, and the last time a representative of this species was seen alive was in 1974.
According to the expert, a number of achievements have been made in the course of scientific work. In particular, scientists have confirmed that the Tokto sea lions are the most "ancient" branch. This species was the first to stand out from the common trunk, and then other species descended from it — California and Galapagos sea lions.
Another discovery, Artyom Nedoluzhko noted, is related to the discovery of traces of crossbreeding of the ancestors of Tokto sea lions with similar species — northern fur seals and sea lions. With the help of such gene transfer (introgression), evolution found new genetic variants, and animals adapted better to the changing environment.
The study may be the first step towards the revival of the species using genetic engineering methods, the scientist suggested.
Read more in the exclusive Izvestia article:
Tokto is better: Russian scientists will help revive extinct sea lions
Переведено сервисом «Яндекс Переводчик»
