Disentangling the Influence of Mutation and Migration in Clonal Seagrasses Using the Genetic Diversity Spectrum for Microsatellites
|Author(s)||Arnaud-Haond Sophie1, 2, Moalic Yann1, Hernandez-Garcia Emilio3, Eguiluz Victor M.3, Alberto Filipe2, 4, Serrao Ester A.2, Duarte Carlos M.5, 6, 7|
|Affiliation(s)||1 : IFREMER, Ctr Brest, Deep LEP, F-29280 Plouzane, France.
2 : Univ Algarve, CCMAR, CIMAR Lab Associado, P-8005139 Faro, Portugal.
3 : CSIC UIB, IFISC, Palma De Mallorca, Spain.
4 : Univ Wisconsin, Dept Biol Sci, Milwaukee, WI 53201 USA.
5 : CSIC UIB, Dept Global Change Res, IMEDEA, Inst Mediterraneo Estudios Avanzados, Mallorca, Spain.
6 : Univ Western Australia, UWA Oceans Inst, Crawley, WA, Australia.
7 : Univ Western Australia, Sch Plant Biol, Crawley, WA, Australia.
|Source||Journal Of Heredity (0022-1503) (Oxford Univ Press Inc), 2014-07 , Vol. 105 , N. 4 , P. 532-541|
|WOS© Times Cited||15|
|Keyword(s)||clonality, Genetic Diversity Spectrum, genetic divergence, microsatellites, seagrass, stepwise mutation|
|Abstract||The recurrent lack of isolation by distance reported at regional scale in seagrass species was recently suggested to stem from stochastic events of large-scale dispersal. We explored the usefulness of phylogenetic information contained in microsatellite loci to test this hypothesis by using the Genetic Diversity Spectrum (GDS) on databases containing, respectively, 7 and 9 microsatellites genotypes for 1541 sampling units of Posidonia oceanica and 1647 of Cymodocea nodosa. The simultaneous increase of microsatellite and geographic distances that emerges reveals a coherent pattern of isolation by distance in contrast to the chaotic pattern previously described using allele frequencies, in particular, for the long-lived P. oceanica. These results suggest that the lack of isolation by distance, rather than the resulting from rare events of large-scale dispersal, reflects at least for some species a stronger influence of mutation over migration at the scale of the distribution range. The global distribution of genetic polymorphism may, therefore, result predominantly from ancient events of step-by-step (re)colonization followed by local recruitment and clonal growth, rather than contemporary gene flow. The analysis of GDS appears useful to unravel the evolutionary forces influencing the dynamics and evolution at distinct temporal and spatial scales by accounting for phylogenetic information borne by microsatellites, under an appropriate mutation model. This finding adds nuance to the generalization of the influence of large-scale dispersal on the dynamics of seagrasses.|