High-Throughput Sequencing of Transposable Elements Insertions Provides Evidence for Adaptive Evolution of the Invasive Asian Tiger Mosquito Towards Temperate Environments

22 Invasive species represent unique opportunities to evaluate the role of local 23 adaptation during colonization of new environments. Among these, the Asian 24 tiger mosquito, Aedes albopictus, is a threatening vector of several human viral 25 diseases, including dengue, chikungunya and the emerging Zika fevers. Its broad 26 presence in both temperate and tropical environments has sometimes been 27 considered as the reflect of a great "ecological plasticity". However, no study has 28 been conducted to assess the role of adaptive evolution in the ecological success 29 of Ae. albopictus at the molecular level. In the present study we performed a 30 genomic scan to search for potential signatures of selection leading to local 31 adaptation in a hundred of field collected mosquitoes from native populations of 32 Vietnam and temperate invasive populations of Europe. High throughput 33 genotyping of transposable element insertions generated more than 120 000 34 polymorphic loci, which in their great majority revealed a virtual absence of 35 structure between bio-geographic areas. Nevertheless, 92 outlier loci show a high 36 level of differentiation between temperate and tropical populations. The majority 37 of these loci segregates at high insertion frequencies among European 38 populations, indicating that this pattern could have been caused by recent events 39 of adaptive evolution in temperate areas. Six outliers were located near putative 40 diapause effector genes, suggesting fine-tuning of this critical pathway during 41 peer-reviewed) is the author/funder. All rights reserved. No reuse allowed without permission.