title: Retracing the routes of introduction of invasive species: the case of the Sirex noctilio woodwasp.
abstract: Understanding the evolutionary histories of invasive species is critical to adopt appropriate management strategies, but this process can be exceedingly complex to unravel. As illustrated in this study of the worldwide invasion of the woodwasp Sirex noctilio, population genetic analyses using coalescent-based scenario testing together with Bayesian clustering and historical records provide opportunities to address this problem. The pest spread from its native Eurasian range to the Southern Hemisphere in the 1900s and recently to Northern America, where it poses economic and potentially ecological threats to planted and native Pinus spp. To investigate the origins and pathways of invasion, samples from five continents were analysed using microsatellite and sequence data. The results of clustering analysis and scenario testing suggest that the invasion history is much more complex than previously believed, with most of the populations being admixtures resulting from independent introductions from Europe and subsequent spread among the invaded areas. Clustering analyses revealed two major source gene pools, one of which the scenario testing suggests is an as yet unsampled source. Results also shed light on the microevolutionary processes occurring during introductions, and showed that only few specimens gave rise to some of the populations. Analyses of microsatellites using clustering and scenario testing considered against historical data drastically altered our understanding of the invasion history of S. noctilio and will have important implications for the strategies employed to fight its spread. This study illustrates the value of combining clustering and ABC methods in a comprehensive framework to dissect the complex patterns of spread of global invaders.
authors.affiliation: Department of Genetics, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, 0002, South Africa. eboissin@gmail.com
authors.forename: E
authors.initials: E
authors.lastname: Boissin
authors.forename: B
authors.initials: B
authors.lastname: Hurley
authors.forename: M J
authors.initials: MJ
authors.lastname: Wingfield
authors.forename: R
authors.initials: R
authors.lastname: Vasaitis
authors.forename: J
authors.initials: J
authors.lastname: Stenlid
authors.forename: C
authors.initials: C
authors.lastname: Davis
authors.forename: P
authors.initials: P
authors.lastname: de Groot
authors.forename: R
authors.initials: R
authors.lastname: Ahumada
authors.forename: A
authors.initials: A
authors.lastname: Carnegie
authors.forename: A
authors.initials: A
authors.lastname: Goldarazena
authors.forename: P
authors.initials: P
authors.lastname: Klasmer
authors.forename: B
authors.initials: B
authors.lastname: Wermelinger
authors.forename: B
authors.initials: B
authors.lastname: Slippers
mesh_terms: D000349:Africa; D000818:Animals; D001499:Bayes Theorem; D016000:Cluster Analysis; D004272:DNA, Mitochondrial; D003576:Electron Transport Complex IV / Q000235:genetics; D005060:Europe; D005260:Female; D005788:Gene Pool; D014644:Genetic Variation; D005828:Genetics, Population; D006239:Haplotypes / Q000235:genetics; D006927:Hymenoptera / Q000235:genetics*; D058865:Introduced Species; D008297:Male; D018895:Microsatellite Repeats; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009656:North America; D013020:South America
chemical_list: D004272:DNA, Mitochondrial; D003576:Electron Transport Complex IV