The genetics and genomics of marine fish invasions: a global review

We present a comprehensive review of the available global literature on the genetics and genomics of marine fish invasions. Overall this review provides data from 66 species belonging to 39 families, collected from 80 published studies on both WoS (Web of Science) and Scopus databases. We found that studies on alien fishes focused on specific geographic areas, mainly the Mediterranean region. Furthermore, most studies restricted their approach to describe patterns of cryptic diversity and/or the development of novel markers, whilst the genetic structure of introduced populations and the genetic mechanisms driving the invasion processes were mostly neglected. The majority of studies on marine fishes reveal similar genetic diversity levels in both native and introduced ranges, suggesting massive or multiple introductions. Indeed, cases of introduced populations showing evidence of bottlenecks were rare. Genetic arrangements are not explained by taxonomic group or reproductive strategy but recent studies reveal rapid evolutionary changes associated with invasive lineages, opening new grounds to investigate mechanisms of adaptation in the natural environment. Finally, the potential of marine fish invasions as a model to test evolutionary responses to rapid environmental changes is further discussed.