The press service of the Kronotsky Nature Reserve reported that this year, scientists surveyed the dammed lakes in the vicinity of the active Dykyy Greben volcano in the South Kamchatka Federal Sanctuary. They paid special attention to Lake Vitaminnoe, where two forms of grayling were found, originating from a single ancestor. Moreover, the evolution of these fish occurred extremely rapidly - in just one and a half thousand years.
Lake Vitaminnoe in its current form was formed about one and a half thousand years ago after a colossal collapse of the northwestern macroslope of the Dykyy Greben volcano. The ichthyofauna of this water body is represented exclusively by resident Dolly Varden, which is divided into two forms. Smaller fish feed on planktonic crustaceans, while larger ones feed on benthic invertebrates, and cases of predation have also been noted among them.
“Different ecological forms of grayling of Lake Vitaminnoe are a newly discovered unique element of the biodiversity of the South Kamchatka Sanctuary. Interestingly, the stable division into two forms occurred in an amazingly short period of time - 1500 years, which indicates a very high rate of evolution and an unprecedented influence of environmental factors on the processes of natural selection,” the message says.
Previously, there were no descriptions in the world scientific literature of such a rapid division of salmon fish into several forms. The materials obtained during the work were transferred to the Laboratory of Ecology of Lower Vertebrates of the A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences for further analysis.
