Evolutionary history of the tiger mosquito, Aedes albopictus, in its native range in Asia

The Asian Tiger Mosquito Aedes albopictus, is one of the 100 worst invasive species in the world and vector of human diseases. In the last 30 years, human activities, in particular the trade of used tires, have fostered the spread of this species from its native range in Asia to Africa, Europe and the Americas. While the modern invasion of Ae. albopictus has been the focus of great interest by the scientific community, the population history and the factors that shaped the current distribution of the species in its native range are still not understood. Here, we used mitochondrial DNA markers to investigate phylogeography and historical demography of Asian native populations of the species. Sequence analyses revealed non-negligible genetic diversity levels, changing the view that native populations of Ae. albopictus have little or no mitochondrial genetic diversity. We found no phylogeographic structure across all Asian populations. This pattern of mtDNA diversity mirrors the patterns previously observed at nuclear markers. The historical demographic analyses suggested that the species in mainland Asia underwent a demographic and spatial expansion starting from 13,000 years ago. By relating genetic data to the Pleistocene paleoenvironmental reconstruction, to the species’ natural history and to the history of human populations since the Last Glacial Maximum, we discuss the possible factors that shaped the current distribution of Ae. albopictus in Asia.