Phylogeography and geographic variation in the Red-bellied Woodpecker : characterization of mtDNA and plumage hybrid zones/Variacion filogeografica y geografica en el Carpintero de Carolina : caracterizacion de ADNmt y plumaje en zonas hibridas

• Published in: The Wilson journal of ornithology 2018-09, Vol.130 (3), p.671
• Main Authors: Barrowclough, George F, Groth, Jeff G, Bramlett, Elizabeth K, Lai, Jonas E, William, M. Mauc
• Format: Article
• Language: English
• Subjects: Genetic populations; Morphological variation; Ornithological research; Picinae
• ISSN: 1559-4491

We used sequences of the mitochondrial ND2 gene, the nuclear TGFB-2 intron-5, and differences in plumage pattern to assay geographic variation in the Red-bellied Woodpecker (Melanerpes carolinus). Ten population samples from throughout its range indicated that ~23% of the mitochondrial genetic variation was distributed among populations, largely due to the occurrence of a clade of haplotypes restricted to the Florida peninsula with a local frequency of 82%. In a hierarchical analysis, 37% of the mtDNA genetic variance was distributed between the Florida peninsula and elsewhere. A strong signal of population growth was detected in the non-peninsular portion of the range. Otherwise, geographic variation in haplotype frequencies was minor, with no evidence of isolation-by-distance. Nuclear intron data showed little variation among populations ([F.sub.st] = 0.007). These results suggest recent secondary contact of 2 differentiated taxa following expansion from allopatric Pleistocene refugia. We modeled the transition in haplotype frequencies along the Florida peninsula as a zone of neutral introgression; the estimated width of that zone was 435 km, and its center was near present day Ocala. Variation in plumage pattern along the peninsula previously had been used to describe a subspecific taxon, M. c. perplexus. We used variation in the forehead pattern of adult males from along the east coast of the United States to model this phenotypic transition; the zone had an estimated width of >2,500 km and an approximate center in the Florida Keys. Taken together, the geographic patterns in mtDNA and plumage variation suggest the populations of Red-bellied Woodpeckers on the Florida peninsula differentiated from those elsewhere during isolation; they are now in secondary contact in a well-known suture zone and represent 2 phylogenetic species connected by wide molecular and morphological zones of introgression. Received 11 May 2017. Accepted 21 November 2017. Key words: hybrid zones, Melanerpes carolinus, ND2, phylogeny, phylogeography, suture zones, TGFB-2. Utilizamos secuencias del gene mitocondrial ND2, intron-5 TGFB-2 nuclear, y diferencias en patrones de plumaje para analizar la variacion geografica del Carpintero de Carolina (Melanerpes carolinus). Diez muestras de todo su rango indicaron que aproximadamente 23% de la variacion genetica mitocondrial se distribuyo entre poblaciones; esto fue debido en gran parte a la ocurrencia de un ciado de haplotipos restringi