Unraveling the invasion history of the Asian tiger mosquito in Europe

Multiple introductions are one of the key features for establishment and persistence of introduced species. However, little is known about the contribution of genetic admixture to the invasive potential of populations. To address this issue, we studied the recent invasion of the Asian tiger mosquito in Europe. We combined genome-wide single nucleotide polymorphisms (SNPs) and historical knowledge to reconstruct the colonization routes, using approximate Bayesian computation, and to establish the demographic dynamics of the invasion. The colonization of Europe involved at least three independent introductions in Albania, North Italy and Central Italy that subsequently acted as dispersal centers throughout Europe. We show that the topology of human transportation networks shaped contrasted demographic histories. Introduction modalities conditioned the levels of genetic diversity in invading populations, and genetically diverse and admixed populations promoted more secondary introductions and have spread farther than single-source invasions. This genomic study provides further crucial insights into a general understanding of the role of genetic diversity promoted by modern trade in driving biological invasions.