Limits...
Progressive migration and anagenesis in Drimys confertifolia of the Juan Fernández Archipelago, Chile.

López-Sepúlveda P, Takayama K, Greimler J, Crawford DJ, Peñailillo P, Baeza M, Ruiz E, Kohl G, Tremetsberger K, Gatica A, Letelier L, Novoa P, Novak J, Stuessy TF - J. Plant Res. (2014)

Bottom Line: A common mode of speciation in oceanic islands is by anagenesis, wherein an immigrant arrives and through time transforms by mutation, recombination, and drift into a morphologically and genetically distinct species, with the new species accumulating a high level of genetic diversity.Drimys confertifolia shows a wide genetic variation within populations on both islands, and values of genetic diversity within populations are similar to those found within populations of the continental progenitor.The genetic results are compatible with the hypothesis of high levels of genetic variation accumulating within anagenetically derived species in oceanic islands, and with the concept of little or no geographical partitioning of this variation over the landscape.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Botánica, Universidad de Concepción, Casilla 160-C, Concepción, Chile.

ABSTRACT
A common mode of speciation in oceanic islands is by anagenesis, wherein an immigrant arrives and through time transforms by mutation, recombination, and drift into a morphologically and genetically distinct species, with the new species accumulating a high level of genetic diversity. We investigate speciation in Drimys confertifolia, endemic to the two major islands of the Juan Fernández Archipelago, Chile, to determine genetic consequences of anagenesis, to examine relationships among populations of D. confertifolia and the continental species D. winteri and D. andina, and to test probable migration routes between the major islands. Population genetic analyses were conducted using AFLPs and nuclear microsatellites of 421 individuals from 42 populations from the Juan Fernández islands and the continent. Drimys confertifolia shows a wide genetic variation within populations on both islands, and values of genetic diversity within populations are similar to those found within populations of the continental progenitor. The genetic results are compatible with the hypothesis of high levels of genetic variation accumulating within anagenetically derived species in oceanic islands, and with the concept of little or no geographical partitioning of this variation over the landscape. Analysis of the probability of migration within the archipelago confirms colonization from the older island, Robinson Crusoe, to the younger island Alejandro Selkirk.

Show MeSH

Related in: MedlinePlus

Genetic affinities from AFLP and microsatellite data among populations of Drimys confertifolia on both islands (a), on Robinson Crusoe Island (b), and Alejandro Selkirk Island (c) by means of STRUCTURE (all K = 2)
© Copyright Policy - OpenAccess
Related In: Results  -  Collection


getmorefigures.php?uid=PMC4300435&req=5

Fig4: Genetic affinities from AFLP and microsatellite data among populations of Drimys confertifolia on both islands (a), on Robinson Crusoe Island (b), and Alejandro Selkirk Island (c) by means of STRUCTURE (all K = 2)

Mentions: Testing for genetically coherent groups in D. confertifolia using the Bayesian approach STRUCTURE 2.3.3 (Fig. 4), the group number K = 2 explained best the groupings found by both AFLPs and microsatellites and revealed a very low degree of admixture among the islands. Analyzing each of the islands separately, K = 2 again best explains the grouping for both molecular markers, however, with a high proportion of individuals showing strong admixture.Fig. 4


Progressive migration and anagenesis in Drimys confertifolia of the Juan Fernández Archipelago, Chile.

López-Sepúlveda P, Takayama K, Greimler J, Crawford DJ, Peñailillo P, Baeza M, Ruiz E, Kohl G, Tremetsberger K, Gatica A, Letelier L, Novoa P, Novak J, Stuessy TF - J. Plant Res. (2014)

Genetic affinities from AFLP and microsatellite data among populations of Drimys confertifolia on both islands (a), on Robinson Crusoe Island (b), and Alejandro Selkirk Island (c) by means of STRUCTURE (all K = 2)
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4300435&req=5

Fig4: Genetic affinities from AFLP and microsatellite data among populations of Drimys confertifolia on both islands (a), on Robinson Crusoe Island (b), and Alejandro Selkirk Island (c) by means of STRUCTURE (all K = 2)
Mentions: Testing for genetically coherent groups in D. confertifolia using the Bayesian approach STRUCTURE 2.3.3 (Fig. 4), the group number K = 2 explained best the groupings found by both AFLPs and microsatellites and revealed a very low degree of admixture among the islands. Analyzing each of the islands separately, K = 2 again best explains the grouping for both molecular markers, however, with a high proportion of individuals showing strong admixture.Fig. 4

Bottom Line: A common mode of speciation in oceanic islands is by anagenesis, wherein an immigrant arrives and through time transforms by mutation, recombination, and drift into a morphologically and genetically distinct species, with the new species accumulating a high level of genetic diversity.Drimys confertifolia shows a wide genetic variation within populations on both islands, and values of genetic diversity within populations are similar to those found within populations of the continental progenitor.The genetic results are compatible with the hypothesis of high levels of genetic variation accumulating within anagenetically derived species in oceanic islands, and with the concept of little or no geographical partitioning of this variation over the landscape.

View Article: PubMed Central - PubMed

Affiliation: Departamento de Botánica, Universidad de Concepción, Casilla 160-C, Concepción, Chile.

ABSTRACT
A common mode of speciation in oceanic islands is by anagenesis, wherein an immigrant arrives and through time transforms by mutation, recombination, and drift into a morphologically and genetically distinct species, with the new species accumulating a high level of genetic diversity. We investigate speciation in Drimys confertifolia, endemic to the two major islands of the Juan Fernández Archipelago, Chile, to determine genetic consequences of anagenesis, to examine relationships among populations of D. confertifolia and the continental species D. winteri and D. andina, and to test probable migration routes between the major islands. Population genetic analyses were conducted using AFLPs and nuclear microsatellites of 421 individuals from 42 populations from the Juan Fernández islands and the continent. Drimys confertifolia shows a wide genetic variation within populations on both islands, and values of genetic diversity within populations are similar to those found within populations of the continental progenitor. The genetic results are compatible with the hypothesis of high levels of genetic variation accumulating within anagenetically derived species in oceanic islands, and with the concept of little or no geographical partitioning of this variation over the landscape. Analysis of the probability of migration within the archipelago confirms colonization from the older island, Robinson Crusoe, to the younger island Alejandro Selkirk.

Show MeSH
Related in: MedlinePlus