TY - JOUR
T1 - Phylogeography and patterns of differentiation in the Curve-billed Thrasher
AU - Rojas-Soto, Octavio R.
AU - De Los Monteros, Alejandro Espinosa
AU - Zink, Robert M.
PY - 2007/5/1
Y1 - 2007/5/1
N2 - Recent mitochondrial DNA (mtDNA) and morphological studies suggest that the Curve-billed Thrasher (Toxostoma curvirostre) consists of three historical groups, corresponding to the subspecies curvirostre and palmeri and a new taxon distributed in Oaxaca and Puebla. Previous mtDNA analysis did not include the subspecies T. c. insularum found on Tiburon Island (Sonora, Mexico). We collected new samples to address the distinctiveness of the three groups, to explore possible contact between the curvirostre and southern clades, to clarify the status of T. c. insularum, and to explore population histories of the major clades. Our mtDNA results confirm the existence of three major haplotype clades, which represent either two or three species depending on the species concept used. We interpret the occurrence of two mismatched haplotypes in Puebla and Oaxaca as recent gene flow. Haplotypes from Tiburon Island were intermixed within the palmeri clade, thereby failing to support the subspecies T. c. insularum. In contrast, principal components analysis of morphological data showed that insularum was distinct and, given the lack of mtDNA distinctiveness, suggests rapid phenotypic evolution on the island. The molecular data suggest that the widespread curvirostre clade has undergone recent population growth, whereas the other two clades appear to have been more stable.
AB - Recent mitochondrial DNA (mtDNA) and morphological studies suggest that the Curve-billed Thrasher (Toxostoma curvirostre) consists of three historical groups, corresponding to the subspecies curvirostre and palmeri and a new taxon distributed in Oaxaca and Puebla. Previous mtDNA analysis did not include the subspecies T. c. insularum found on Tiburon Island (Sonora, Mexico). We collected new samples to address the distinctiveness of the three groups, to explore possible contact between the curvirostre and southern clades, to clarify the status of T. c. insularum, and to explore population histories of the major clades. Our mtDNA results confirm the existence of three major haplotype clades, which represent either two or three species depending on the species concept used. We interpret the occurrence of two mismatched haplotypes in Puebla and Oaxaca as recent gene flow. Haplotypes from Tiburon Island were intermixed within the palmeri clade, thereby failing to support the subspecies T. c. insularum. In contrast, principal components analysis of morphological data showed that insularum was distinct and, given the lack of mtDNA distinctiveness, suggests rapid phenotypic evolution on the island. The molecular data suggest that the widespread curvirostre clade has undergone recent population growth, whereas the other two clades appear to have been more stable.
KW - Gene tree
KW - Introgression
KW - Morphometric variation
KW - Phylogeography
KW - Species limits
KW - Subspecies
KW - Toxostoma curvirostre
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U2 - 10.1650/0010-5422(2007)109[456:PAPODI]2.0.CO;2
DO - 10.1650/0010-5422(2007)109[456:PAPODI]2.0.CO;2
M3 - Article
AN - SCOPUS:34248683939
SN - 0010-5422
VL - 109
SP - 456
EP - 463
JO - Condor
JF - Condor
IS - 2
ER -