A Cytochrome-b Perspective on Passerina Bunting Relationships

We sequenced the complete mitochondrial cytochrome-b gene (1,143 nucleotides) for representatives of each species in the cardinalid genera Passerina (6 species), Guiraca (1 species), and Cyanocompsa (3 species), and used a variety of phylogenetic methods to address relationships within and among genera. We determined that Passerina, as presently recognized, is paraphyletic. Lazuli Bunting (P. amoena) is sister to the much larger Blue Grosbeak (Guiraca caerulea). Indigo Bunting (P. cyanea) and Lazuli Bunting are not sister taxa as generally thought. In all weighted parsimony trees and for the gamma-corrected HKY tree, Indigo Bunting is the sister of two sister groups, a “blue” (Lazuli Bunting and Blue Grosbeak) and a “painted” (Rosita\u27s Bunting [P. rositae], Orange-breasted Bunting [P. leclancherii], Varied Bunting [P. versicolor], and Painted Bunting [P. ciris]) clade. The latter two species form a highly supported sister pair of relatively more recent origin. Uncorrected (p) distances for ingroup (Passerina and Guiraca) taxa range from 3.0% (P. versicolor–P. ciris) to 7.6% (P. cyanea–P. leclancherii) and average 6.5% overall. Assuming a molecular clock, a bunting “radiation” between 4.1 and 7.3 Mya yielded four lineages. This timing is consistent with fossil evidence and coincides with a late-Miocene cooling during which a variety of western grassland habitats evolved. A reduction in size at that time may have allowed buntings to exploit that new food resource (grass seeds). We speculate that the Blue Grosbeak subsequently gained large size and widespread distribution as a result of ecological character displacement

Pciris_reads_6of6

100bp SR sequence reads from an illumina Hiseq 2500 for Passerina ciris. Library prepped via ddRAD protocol with enzymes sbf1 and msp1. Reads were demultiplexed in pyrad v 3-0-65 (command "pyrad -p params.txt -s 1") but have had no other processing

Pciris_reads_4of6

100bp SR sequence reads from an illumina Hiseq 2500 for Passerina ciris. Library prepped via ddRAD protocol with enzymes sbf1 and msp1. Reads were demultiplexed in pyrad v 3-0-65 (command "pyrad -p params.txt -s 1") but have had no other processing

Pciris_reads_2of6

100bp SR sequence reads from an illumina Hiseq 2500 for Passerina ciris. Library prepped via ddRAD protocol with enzymes sbf1 and msp1. Reads were demultiplexed in pyrad v 3-0-65 (command "pyrad -p params.txt -s 1") but have had no other processing

Pciris_reads_3of6

100bp SR sequence reads from an illumina Hiseq 2500 for Passerina ciris. Library prepped via ddRAD protocol with enzymes sbf1 and msp1. Reads were demultiplexed in pyrad v 3-0-65 (command "pyrad -p params.txt -s 1") but have had no other processing

Data from: A migratory divide in the painted bunting (Passerina ciris)

In the Painted Bunting (Passerina ciris), a North American songbird, populations on the Atlantic coast and interior southern United States are known to be allopatric during the breeding season, but efforts to map connectivity with wintering ranges have been largely inconclusive. Using genomic and morphological data from museum specimens and banded birds, we found evidence of three genetically differentiated Painted Bunting populations with distinct wintering ranges and molt-migration phenologies. In addition to confirming that the Atlantic coast population remains allopatric throughout the annual cycle, we identified an unexpected migratory divide within the interior breeding range. Populations breeding in Louisiana winter on the Yucatán Peninsula, and are parapatric with other interior populations that winter in mainland Mexico and Central America. Across the interior breeding range, genetic ancestry is also associated with variation in wing length, suggesting that selection may be promoting morphological divergence in populations with different migration strategies

Pciris_mtDNA_ND2

ND2 sequence alignment in phylip forma

R_scripts

R scripts used for multivariate genomic analysis, mtDNA analysis, morphology, dadi data preparation, dadi model to demographic value conversion, and all figures

ddRAD_assembly

ddRAD sequence assembly in vcf and structure format, and pyRAD sequence assembly parameters file

dadi

demographic analysis (dadi) python scripts and dadi-formatted input file