TY - JOUR

T1 - Replicated anthropogenic hybridisations reveal parallel patterns of admixture in marine mussels

AU - Simon, Alexis

AU - Arbiol, Christine

AU - Nielsen, Einar Eg

AU - Couteau, Jérôme

AU - Sussarellu, Rossana

AU - Burgeot, Thierry

AU - Bernard, Ismaël

AU - Coolen, Joop W.P.

AU - Lamy, Jean-Baptiste

AU - Robert, Stéphane

AU - Skazina, Maria

AU - Strelkov, Petr

AU - Queiroga, Henrique

AU - Cancio, Ibon

AU - Welch, John J.

AU - Viard, Frédérique

AU - Bierne, Nicolas

N1 - Publisher Copyright: © 2019 The Authors. Evolutionary Applications published by John Wiley & Sons Ltd

PY - 2019/11/22

Y1 - 2019/11/22

N2 - Human‐mediated transport creates secondary contacts between genetically differentiated lineages, bringing new opportunities for gene exchange. When similar introductions occur in different places, they provide informally replicated experiments for studying hybridisation. We here examined 4279 Mytilus mussels, sampled in Europe and genotyped with 77 ancestry informative markers. We identified a type of introduced mussels, called ‘dock mussels’, associated with port habitats and displaying a particular genetic signal of admixture between M. edulis and the Mediterranean lineage of M. galloprovincialis. These mussels exhibit similarities in their ancestry compositions, regardless of the local native genetic backgrounds and the distance separating colonised ports. We observed fine‐scale genetic shifts at the port entrance, at scales below natural dispersal distance. Such sharp clines do not fit with migration‐selection tension zone models, and instead suggest habitat choice and early stage adaptation to the port environment, possibly coupled with connectivity barriers. Variations in the spread and admixture patterns of dock mussels seem to be influenced by the local native genetic backgrounds encountered. We next examined departures from the average admixture rate at different loci, and compared human‐mediated admixture events, to naturally admixed populations and experimental crosses. When the same M. galloprovincialis background was involved, positive correlations in the departures of loci across locations were found; but when different backgrounds were involved, no or negative correlations were observed. While some observed positive correlations might be best explained by a shared history and saltatory colonisation, others are likely produced by parallel selective events. Altogether, genome‐wide effect of admixture seems repeatable, and more dependent on genetic background than environmental context. Our results pave the way towards further genomic analyses of admixture, and monitoring of the spread of dock mussels both at large and fine spacial scales.

AB - Human‐mediated transport creates secondary contacts between genetically differentiated lineages, bringing new opportunities for gene exchange. When similar introductions occur in different places, they provide informally replicated experiments for studying hybridisation. We here examined 4279 Mytilus mussels, sampled in Europe and genotyped with 77 ancestry informative markers. We identified a type of introduced mussels, called ‘dock mussels’, associated with port habitats and displaying a particular genetic signal of admixture between M. edulis and the Mediterranean lineage of M. galloprovincialis. These mussels exhibit similarities in their ancestry compositions, regardless of the local native genetic backgrounds and the distance separating colonised ports. We observed fine‐scale genetic shifts at the port entrance, at scales below natural dispersal distance. Such sharp clines do not fit with migration‐selection tension zone models, and instead suggest habitat choice and early stage adaptation to the port environment, possibly coupled with connectivity barriers. Variations in the spread and admixture patterns of dock mussels seem to be influenced by the local native genetic backgrounds encountered. We next examined departures from the average admixture rate at different loci, and compared human‐mediated admixture events, to naturally admixed populations and experimental crosses. When the same M. galloprovincialis background was involved, positive correlations in the departures of loci across locations were found; but when different backgrounds were involved, no or negative correlations were observed. While some observed positive correlations might be best explained by a shared history and saltatory colonisation, others are likely produced by parallel selective events. Altogether, genome‐wide effect of admixture seems repeatable, and more dependent on genetic background than environmental context. Our results pave the way towards further genomic analyses of admixture, and monitoring of the spread of dock mussels both at large and fine spacial scales.

KW - biological introductions

KW - bentho-pelagic species

KW - ports

KW - secondary contact

KW - clines

KW - admixture

KW - biological introductions

KW - bentho‐pelagic species

KW - ports

KW - secondary contact

KW - clines

KW - Admixture

KW - bentho-pelagic species

KW - admixture

KW - COAST POPULATIONS

KW - EDULIS

KW - OCEAN SPRAWL

KW - MYTILUS-GALLOPROVINCIALIS LMK

KW - INTROGRESSION

KW - GENETIC DIVERSITY

KW - BLUE MUSSELS

KW - MOSAIC HYBRID ZONE

KW - BALLAST-WATER

KW - R-PACKAGE

UR - http://www.scopus.com/inward/record.url?scp=85075485363&partnerID=8YFLogxK

UR - http://www.mendeley.com/research/replicated-anthropogenic-hybridisations-reveal-parallel-patterns-admixture-marine-mussels

U2 - 10.1111/eva.12879

DO - 10.1111/eva.12879

M3 - Article

JO - Evolutionary Applications

JF - Evolutionary Applications

SN - 1752-4571

ER -