TY - JOUR
T1 - In situ genetic differentiation in a Hispaniolan lizard (Ameiva chrysolaema)
T2 - A multilocus perspective
AU - Gifford, Matthew E.
AU - Larson, Allan
N1 - Funding Information:
The authors thank R.B. Langerhans and V. Rodriguez for assistance in the field, S. Woolley for assistance with the cross-validation analyses, and J. Beck and three anonymous reviewers for helpful comments on earlier versions of this manuscript. Financial support for this research was provided by a Doctoral Dissertation Improvement Grant (DDIG) from the National Science Foundation (DEB 0508344) and the Grants-in-Aid of Research (GIAR) Program from the Society of Integrative and Comparative Biology (MEG). This work was conducted under research permits #01339 and #000877 administered by the Secretaría de Estado de Medio Ambiente y Resursos Naturales and the Subsecretaría de Estado de Áreas Protegidas y Biodiversidad de la República Dominicana.
PY - 2008/10
Y1 - 2008/10
N2 - A previous phylogeographic study of mitochondrial haplotypes for the Hispaniolan lizard Ameiva chrysolaema revealed deep genetic structure associated with seawater inundation during the late Pliocene/early Pleistocene and evidence of subsequent population expansion into formerly inundated areas. We revisit hypotheses generated by our previous study using increased geographic sampling of populations and analysis of three nuclear markers (α-enolase intron 8, α-cardiac-actin intron 4, and β-actin intron 3) in addition to mitochondrial haplotypes (ND2). Large genetic discontinuities correspond spatially and temporally with historical barriers to gene flow (sea inundations). NCPA cross-validation analysis and Bayesian multilocus analyses of divergence times (IMa and MCMCcoal) reveal two separate episodes of fragmentation associated with Pliocene and Pleistocene sea inundations, separating the species into historically separate Northern, East-Central, West-Central, and Southern population lineages. Multilocus Bayesian analysis using IMa indicates asymmetrical migration from the East-Central to the West-Central populations following secondary contact, consistent with expectations from the more pervasive sea inundation in the western region. The West-Central lineage has a genetic signature of population growth consistent with the expectation of geographic expansion into formerly inundated areas. Within each lineage, significant spatial genetic structure indicates isolation by distance at comparable temporal scales. This study adds to the growing body of evidence that vicariant speciation may be the prevailing source of lineage accumulation on oceanic islands. Thus, prior theories of island biogeography generally underestimate the role and temporal scale of intra-island vicariant processes.
AB - A previous phylogeographic study of mitochondrial haplotypes for the Hispaniolan lizard Ameiva chrysolaema revealed deep genetic structure associated with seawater inundation during the late Pliocene/early Pleistocene and evidence of subsequent population expansion into formerly inundated areas. We revisit hypotheses generated by our previous study using increased geographic sampling of populations and analysis of three nuclear markers (α-enolase intron 8, α-cardiac-actin intron 4, and β-actin intron 3) in addition to mitochondrial haplotypes (ND2). Large genetic discontinuities correspond spatially and temporally with historical barriers to gene flow (sea inundations). NCPA cross-validation analysis and Bayesian multilocus analyses of divergence times (IMa and MCMCcoal) reveal two separate episodes of fragmentation associated with Pliocene and Pleistocene sea inundations, separating the species into historically separate Northern, East-Central, West-Central, and Southern population lineages. Multilocus Bayesian analysis using IMa indicates asymmetrical migration from the East-Central to the West-Central populations following secondary contact, consistent with expectations from the more pervasive sea inundation in the western region. The West-Central lineage has a genetic signature of population growth consistent with the expectation of geographic expansion into formerly inundated areas. Within each lineage, significant spatial genetic structure indicates isolation by distance at comparable temporal scales. This study adds to the growing body of evidence that vicariant speciation may be the prevailing source of lineage accumulation on oceanic islands. Thus, prior theories of island biogeography generally underestimate the role and temporal scale of intra-island vicariant processes.
KW - Coalescence
KW - Island biogeography
KW - Isolation-with-migration
KW - Multilocus
KW - NCPA
KW - Phylogeography
UR - http://www.scopus.com/inward/record.url?scp=52049121046&partnerID=8YFLogxK
U2 - 10.1016/j.ympev.2008.06.003
DO - 10.1016/j.ympev.2008.06.003
M3 - Article
C2 - 18611442
AN - SCOPUS:52049121046
SN - 1055-7903
VL - 49
SP - 277
EP - 291
JO - Molecular Phylogenetics and Evolution
JF - Molecular Phylogenetics and Evolution
IS - 1
ER -