Researchers trace the journey of malaria-carrying mosquitoes from the American continents to Europe, arguing that the route runs through Siberia. This conclusion was reported by TASS, citing the press service of Tomsk State University. The study offers a detailed look at how these insects moved across vast landscapes and climate zones, shaping the distribution of disease vectors far beyond their original range.
In the project, scientists analyzed more than 1,300 genes and sequenced the genomes of 13 mosquito species. Using the genetic data, they constructed an evolutionary tree that centers on two North American species, shedding light on how these insects diverged and adapted over time. A key finding points to a Siberian lineage of Anopheles that appears to occupy a pivotal position in the Eurasian radiation of these mosquitoes. This lineage is described as an ancestor to many Eurasian species, including those now found in Europe, highlighting a deep historical connection between North American and Eurasian mosquito populations.
According to the researchers, the mosquitoes crossed into Siberia via the Bering Isthmus, an ancient land bridge that once connected two continents. Once in the northern regions, they faced severe environmental constraints that spurred rapid adaptation. One notable adaptation was diapause, a state of suspended development that allowed females to survive harsh winters. Female mosquitoes could feed on blood shortly before winter, but instead of laying eggs immediately, they stored energy as fat. In spring, after awakening, they resumed activity, sought blood meals, and laid eggs, thereby restarting the life cycle and enabling the spread of these mosquitoes to new areas.
The harsh climate exerted strong selective pressure, pushing the species to develop genetic mechanisms that supported resilience to a wide range of weather patterns. These genetic adaptations not only facilitated survival in cold and variable conditions but also enabled broader dissemination into old-world territories. Over time, such changes contributed to the establishment of mosquito populations that became vectors for serious diseases in their adopted habitats as well as in their homeland, underscoring the complex relationship between climate, genetics, and disease ecology.
In a curious note, the historical discussion of this topic touches on early experiments by ancient biologists who explored artificial methods related to fat production in laboratory settings, a reference that underscores the long-standing scientific interest in mosquito biology and metabolic processes. [citation: TASS, via Tomsk State University press service]”