title: Tracing the trans-pacific evolutionary history of a domesticated Seaweed (Gracilaria chilensis) with archaeological and genetic data.
abstract: The history of a domesticated marine macroalga is studied using archaeological, phylogeographic and population genetic tools. Phylogeographic and population genetic analyses demonstrated that the cultivated red alga Gracilaria chilensis colonised the Chilean coast from New Zealand. Combining archaeological observations with phylogeographic data provided evidence that exchanges between New Zealand and Chile have occurred at least before the Holocene, likely at the end of the Last Glacial Maximum (LGM) and we suggest that migration probably occurred via rafting. Furthermore, the remarkably low microsatellite diversity found in the Chilean populations compared to those in New Zealand is consistent with a recent genetic bottleneck as a result of over-exploitation of natural populations and/or the process of domestication. Therefore, the aquaculture of this seaweed, based essentially on clonal propagation, is occurring from genetically depressed populations and may be driving the species to an extinction vortex in Chile.
authors.affiliation: Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile; CNRS, Sorbonne Universités, UPMC University Paris VI, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, CS 90074, Place G. Tessier, 296888 Roscoff, France.
authors.forename: Marie-Laure
authors.initials: ML
authors.lastname: Guillemin
authors.affiliation: CNRS, Sorbonne Universités, UPMC University Paris VI, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, CS 90074, Place G. Tessier, 296888 Roscoff, France.
authors.forename: Myriam
authors.initials: M
authors.lastname: Valero
authors.affiliation: CNRS, Sorbonne Universités, UPMC University Paris VI, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, CS 90074, Place G. Tessier, 296888 Roscoff, France; Centro de Conservación Marina and CeBiB, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Faugeron
authors.affiliation: National Institute of Water & Atmospheric Research, School of Biological Sciences, University of Auckland, Private Bag 14901, Wellington 6241, New Zealand.
authors.forename: Wendy
authors.initials: W
authors.lastname: Nelson
authors.affiliation: CNRS, Sorbonne Universités, UPMC University Paris VI, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, CS 90074, Place G. Tessier, 296888 Roscoff, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Destombe
mesh_terms: D001106:Archaeology; D021901:DNA, Intergenic / Q000235:genetics; D019143:Evolution, Molecular; D014644:Genetic Variation; D044724:Gracilaria / Q000235:genetics*; D018895:Microsatellite Repeats / Q000235:genetics; D010140:Pacific Ocean; D058974:Phylogeography; D012624:Seaweed / Q000235:genetics*
chemical_list: D021901:DNA, Intergenic