Scientists opened a new chapter in the study of malaria mosquitoes
In December 2016, the American Journal of Vector Ecology published two articles by Yuri Novikov, a scientist at the TSU Biological Institute devoted to the study of ecology and the distribution one of the species of malaria mosquito of the maculipennis complex and its laboratory cultivation. Hybridization has turned a new page in the study of malaria mosquitoes, allowing more accurate investigation of their physiology and their ability to transfer the malaria plasmodium that causes malaria.
– The article presents the results of developing a method of cultivating Anopheles beklemishevi in the laboratory, which helps us to solve two problems at once, – says Yuri Novikov. – First, with growing mosquitoes, we can work with them not seasonally but year-round. Second, as a result of laboratory cultivation, we get virgin females, without which the hybridization process is not possible.
He said that crossing the Anopheles beklemishevi species, discovered and described by TSU geneticists 40 years ago, with Anopheles atroparvus was accomplished for the first time. It does not occur under natural conditions. The study of hybrids provides an opportunity to assess the degree of reproductive compatibility of species, which is an important argument in the reconstruction of the evolution of this group of related species. Experiments in the laboratory will allow predicting the likely composition of the species of mosquitoes and the epidemiological situation in Siberia due to the rapidly changing climate.
Along with this, in the course of a detailed study and comparative analysis of 8,000 specimens collected from 34 Russian and Kazakhstan areas, it was determined that the habitat of species Anopheles beklemishevi is much wider than expected: it spread from Estonia to Yakutia and from the Arctic to the Altai and Sayan. The relative population of the species is low everywhere, moreover, in the south of Western Siberia and Altai the frequency has been steadily reduced. So, in the vicinity of Tomsk (Kolarovo), the proportion of Anopheles beklemishevi in the total number of malaria mosquitoes has dropped from 25% in 1976 to 3.2% now.
According to the scientist, the discovery of the representatives of this type in Yakutia is an indirect confirmation of the idea that malaria mosquitoes of the maculipennis complex came to Eurasia from America through the Bering Land Bridge.
Yuri Novikov's studies show that as a result of climate change there is an expansion of the area of the southwestern species of mosquitoes. They are moving to the northeast, conquering a new environment successfully, and breeding in areas where they previously could not survive.